1. |
Jarząbek D. M., Włoczewski M.♦, Milczarek M., Jenczyk P., Takesue N.♦, Golasiński K.♦, Pieczyska E. A., Deformation Mechanisms of (100) and (110) Single-Crystal BCC Gum Metal Studied by Nanoindentation and Micropillar Compression,
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, ISSN: 1073-5623, DOI: 10.1007/s11661-024-07605-3, pp.1-11, 2024Abstract: In this paper, small-scale testing techniques—nanoindentation and micropillar compression—were used to investigate the deformation mechanisms, size effects, and strain rate sensitivity of (100) and (110) single-crystal Gum Metal at the micro/nanoscale. It was observed that the (100) orientation exhibits a significant size effect, resulting in hardness values ranging from 1 to 5 GPa. Conversely, for the (110) orientation, this effect was weaker. Furthermore, the yield strength obtained from the micropillar compression tests was approximately 740 MPa for the (100) orientation and 650 MPa for the (110) orientation. The observed deformations were consistent with the established features of the deformation behavior of body-centered cubic (bcc) alloys: significant strain rate sensitivity with no depth dependence, pile-up patterns comparable to those reported in the literature, and shear along the {112}<111> slip directions. However, the investigated material also exhibited Gum Metal-like high ductility, a relatively low modulus of elasticity, and high yield strength, which distinguishes it from classic bcc alloys. Affiliations:
Jarząbek D. M. | - | IPPT PAN | Włoczewski M. | - | other affiliation | Milczarek M. | - | IPPT PAN | Jenczyk P. | - | IPPT PAN | Takesue N. | - | Fukuoka University (JP) | Golasiński K. | - | other affiliation | Pieczyska E. A. | - | IPPT PAN |
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2. |
Golasiński K.♦, Maj M., Tasaki W.♦, Pieczyska E.A., Kim H.♦, Full-Field Deformation Study of Ti–25Nb, Ti–25Nb–0.3O and Ti–25Nb–0.7O Shape Memory Alloys During Tension Using Digital Image Correlation,
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, ISSN: 1073-5623, DOI: 10.1007/s11661-024-07414-8, pp.1-10, 2024Abstract: A Ti–25Nb shape memory alloy (SMA) exhibits shape memory effect associated with stress-induced martensitic transformation from β to α″ phase. Addition of oxygen stabilizes the β phase and changes stress–strain response. Oxygen-added Ti–25Nb SMAs show a more distinct superelastic behavior. In this work, digital image correlation (DIC) was applied to investigate for the first time full-field deformation of Ti–25Nb, Ti–25Nb–0.3O and Ti–25Nb–0.7O (at. pct) SMAs. The specimens were subjected to loading–unloading tensile tests to study local and global mechanical characteristics related to activity of particular deformation mechanisms of the SMAs. Strain and strain rate fields were quantitatively compared at selected stages of each SMA’s deformation. It was found that the Ti–25Nb SMA exhibits a macroscopically localized Lüders-type deformation associated with the stress-induced phase transformation, whereas Ti–25Nb–0.3O and Ti–25Nb–0.7O SMAs show more discrete types of deformation related to activity of interstitial oxygen atoms. As a consequence, at particular stages of deformation, local values of strain rate of Ti–25Nb SMA were significantly higher than those of average strain rate. The results obtained in this paper provide a better understanding of the deformation mechanism in the oxygen-added Ti–25Nb based SMAs. Affiliations:
Golasiński K. | - | other affiliation | Maj M. | - | IPPT PAN | Tasaki W. | - | other affiliation | Pieczyska E.A. | - | IPPT PAN | Kim H. | - | other affiliation |
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3. |
Staszczak M., Urbański L., Gradys A. D., Cristea M.♦, Pieczyska E. A., Nucleation, Development and Healing of Micro-Cracks in Shape Memory Polyurethane Subjected to Subsequent Tension Cycles,
Polymers, ISSN: 2073-4360, DOI: 10.3390/polym16131930, Vol.16, No.13, pp.1-22, 2024Abstract: Thermoresponsive shape memory polymers (SMPs) have garnered increasing interest for their exceptional ability to retain a temporary shape and recover the original configuration through temperature changes, making them promising in various applications. The SMP shape change and recovery that happen due to a combination of mechanical loading and appropriate temperatures are related to its particular microstructure. The deformation process leads to the formation and growth of micro-cracks in the SMP structure, whereas the subsequent heating over its glass transition temperature Tg leads to the recovery of its original shape and properties. These processes also affect the SMP microstructure. In addition to the observed macroscopic shape recovery, the healing of micro-crazes and micro-cracks that have nucleated and developed during the loading occurs. Therefore, our study delves into the microscopic aspect, specifically addressing the healing of micro-cracks in the cyclic loading process. The proposed research concerns a thermoplastic polyurethane shape memory polymer (PU-SMP) MM4520 with a Tg of 45 °C. The objective of the study is to investigate the effect of the number of tensile loading-unloading cycles and thermal shape recovery on the evolution of the PU-SMP microstructure. To this end, comprehensive research starting from structural characterization of the initial state and at various stages of the PU-SMP mechanical loading was conducted. Dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), wide-angle X-ray scattering (WAXS) and scanning electron microscopy (SEM) were used. Moreover, the shape memory behavior in the thermomechanical loading program was investigated. The obtained average shape fixity value was 99%, while the shape recovery was 92%, which confirmed good shape memory properties of the PU-SMP. Our findings reveal that even during a single loading-unloading tension cycle, crazes and cracks nucleate on the surface of the PU-SMP specimen, whereas the subsequent temperature-induced shape recovery process carried out at the temperature above Tg enables the healing of micro-cracks. Interestingly, the surface of the specimen after three and five loading-unloading cycles did not exhibit crazes and cracks, although some traces of cracks were visible. The traces disappeared after exposing the material to heating at Tg + 20 °C (65 °C) for 30 min. The crack closure phenomenon during deformation, even without heating over Tg, occurred within three and five subsequent cycles of loading-unloading. Notably, in the case of eight loading-unloading cycles, cracks appeared on the surface of the PU-SMP and were healed only after thermal recovery at the particular temperature over Tg. Upon reaching a critical number of cycles, the proper amount of energy required for crack propagation was attained, resulting in wide-open cracks on the material’s surface. It is worth noting that WAXS analysis did not indicate strong signs of typical highly ordered structures in the PU-SMP specimens in their initial state and after the loading history; however, some orientation after the cyclic deformation was observed. Keywords: polyurethane shape memory polymer, glass transition temperature, tensile loading cycles, structure analysis, micro-cracks, healing Affiliations:
Staszczak M. | - | IPPT PAN | Urbański L. | - | IPPT PAN | Gradys A. D. | - | IPPT PAN | Cristea M. | - | Petru Poni Institute of Macromolecular Chemistry (RO) | Pieczyska E. A. | - | IPPT PAN |
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4. |
Staszczak M., Urbański L., Cristea M.♦, Ionita D.♦, Pieczyska E.A., Investigation of Shape Memory Polyurethane Properties in Cold Programming Process Towards Its Applications,
Polymers, ISSN: 2073-4360, DOI: 10.3390/polym16020219, Vol.16, No.2, pp.219-1-219-20, 2024Abstract: Thermoresponsive shape memory polymers (SMPs) with the remarkable ability to remember a temporary shape and recover their original one using temperature have been gaining more and more attention in a wide range of applications. Traditionally, SMPs are investigated using a method named often “hot-programming”, since they are heated above their glass transition temperature (Tg) and after that, reshaped and cooled below Tg to achieve and fix the desired configuration. Upon reheating, these materials return to their original shape. However, the heating of SMPs above their Tg during a thermomechanical cycle to trigger a change in their shape creates a temperature gradient within the material structure and causes significant thermal expansion of the polymer sample resulting in a reduction in its shape recovery property. These phenomena, in turn, limit the application fields of SMPs, in which fast actuation, dimensional stability and low thermal expansion coefficient are crucial. This paper aims at a comprehensive experimental investigation of thermoplastic polyurethane shape memory polymer (PU-SMP) using the cold programming approach, in which the deformation of the SMP into the programmed shape is conducted at temperatures below Tg. The PU-SMP glass transition temperature equals approximately 65 ◦C. Structural, mechanical and thermomechanical characterization was performed, and the results on the identification of functional properties of PU-SMPs in quite a large strain range beyond yield limit were obtained. The average shape fixity ratio of the PU-SMP at room temperature programming was found to be approximately 90%, while the average shape fixity ratio at 45 ◦C (Tg − 20 ◦C) was approximately 97%. Whereas, the average shape recovery ratio was 93% at room temperature programming and it was equal to approximately 90% at 45 ◦C. However, the results obtained using the traditional method, the so-called hot programming at 65 ◦C, indicate a higher shape fixity value of 98%, but a lower shape recovery of 90%. Thus, the obtained results confirmed good shape memory properties of the PU-SMPs at a large strain range at various temperatures. Furthermore, the experiments conducted at both temperatures below Tg demonstrated that cold programming can be successfully applied to PU-SMPs with a relatively high Tg. Knowledge of the PU-SMP shape memory and shape fixity properties, estimated without risk of material degradation, caused by heating above Tg, makes them attractive for various applications, e.g., in electronic components, aircraft or aerospace structures. Keywords: polyurethane shape memory polymer, cold programming, thermal expansion, shape fixity, shape recovery Affiliations:
Staszczak M. | - | IPPT PAN | Urbański L. | - | IPPT PAN | Cristea M. | - | Petru Poni Institute of Macromolecular Chemistry (RO) | Ionita D. | - | other affiliation | Pieczyska E.A. | - | IPPT PAN |
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5. |
Nabavian Kalat M., Staszczak M., Urbański L., Fernandez C.♦, Vega C.♦, Cristea M.♦, Ionita D.♦, Lantada A.♦, Pieczyska E.A., Investigating a shape memory epoxy resin and its application to engineering shape-morphing devices empowered through kinematic chains and compliant joints,
MATERIALS AND DESIGN, ISSN: 0264-1275, DOI: 10.1016/j.matdes.2023.112263, Vol.233, No.112263, pp.1-15, 2023Abstract: 4D printing is the additive manufacturing (3D printing) of objects that can transform their shape in a controlled and predictable way when subjected to external stimuli. A thermo-responsive shape memory polymer (SMP) is a highly suitable material to 4D print smart devices, due to its actuation function and the capability of recovering its original shape from the deformed one upon heating. This study presents the results of employing an epoxy resin in the additive manufacturing of complex-shaped smart devices with shape-morphing properties using laser stereolithography (SLA). To quantify the shape memory behaviour of the shape memory epoxy (SMEp), we first investigate the thermomechanical properties of the 3D-printed specimens in a tensile testing machine coupled with an environmental thermal chamber. This approach allows us to determine the shape fixity and recovery of SMEp. Next, we propose effective designs of complex-shaped devices, with the aim of promoting shape morphing through micro-actuators and compliant joints acting as active regions in combination with multiplying mechanisms or kinematic chains in each of the devices. We manufacture the complex-shaped prototypes by using SLA directly from the computer-aided designs. The shape memory trials of the 3D-printed prototypes reveal quite precise shape recovery of the devices, illustrating their shape-memory. In fact, the inclusion of micro-actuators and compliant joints within the complex-geometry devices allows for local triggering, deformation and recovery, resulting in a prompt response of the devices to heat. Therefore, innovative designs, along with the suitable smart material and high-quality manufacturing process, lead to 4D printed devices with fast actuation and shape-morphing properties. Overall, this research may contribute to the development of smart materials and 4D printing technology for applications in fields such as biomedical engineering, robotics, transport and aerospace engineering. Keywords: Shape memory polymers,Shape memory epoxy,Shape morphing structures,Laser stereolithography,3D and 4D printing Affiliations:
Nabavian Kalat M. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Urbański L. | - | IPPT PAN | Fernandez C. | - | other affiliation | Vega C. | - | other affiliation | Cristea M. | - | Petru Poni Institute of Macromolecular Chemistry (RO) | Ionita D. | - | other affiliation | Lantada A. | - | other affiliation | Pieczyska E.A. | - | IPPT PAN |
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6. |
Golasiński K., Maj M., Urbański L., Staszczak M., Gradys A.D., Pieczyska E.A., Experimental study of thermomechanical behaviour of Gum Metal during cyclic tensile loadings: the quantitative contribution of IRT and DIC,
Quantitative InfraRed Thermography Journal, ISSN: 1768-6733, DOI: 10.1080/17686733.2023.2205762, pp.1-18, 2023Abstract: Thermomechanical behaviour of Gum Metal (Ti–23Nb–0.7Ta–2.0Zr–1.2O, at.%) under cyclic tension was experimentally investigated using infrared thermography and digital image correlation. The thermomechanical characteristics of particular stages of the subsequent loading-unloading cycles of Gum Metal were identified, i.e. (I) the linear, elastic loading accompanied by the temperature drop, (II) the nonlinear super-elastic loading related to the temperature growth, (III) the transient stage (at which both the superelastic-like behaviour and the plastic one are present simultaneously) and the temperature starts growing fast, (IV) the plastic deformation with a significant growth of temperature, (V) the superelastic-like unloading accompanied by a fast drop in temperature, (VI) the transient unloading with a slower decrease in temperature and (VII) the elastic unloading, with a slight increase in temperature. Thermoelastic effect in Gum Metal during both loading and unloading was analysed in each tensile cycle. Finally, the evolution of strain and temperature fields just before unloading in each cycle was discussed and a comparison of the fields at selected stages of cycles 12 and 24 was presented. The results of this work enabled us to identify the non-dissipative processes of elastic and superelastic-like deformations as well as the dissipative process of plastic deformation. Keywords: Gum Metal,β-Ti alloy,cyclic tension,superelasticity,thermoelastic effect,infrared thermography,digital image correlation Affiliations:
Golasiński K. | - | IPPT PAN | Maj M. | - | IPPT PAN | Urbański L. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Gradys A.D. | - | IPPT PAN | Pieczyska E.A. | - | IPPT PAN |
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7. |
Golasiński K., Staszczak M., Pieczyska E.A., Energy Storage and Dissipation in Consecutive Tensile Load-Unload Cycles of Gum Metal,
Materials, ISSN: 1996-1944, DOI: 10.3390/ma16093288, Vol.16, No.9, pp.1-17, 2023Abstract: Multifunctional β-titanium alloy Gum Metal, characterized by a relatively low elastic modulus, superelastic-like behavior and high strength, was subjected to cyclic tensile loadings. The characteristics of macroscopic scale energy storage and dissipation in the consecutive loading–unloading cycles were studied. Various kinds of energy components related to the alloy deformation process were determined experimentally and analyzed using thermodynamic relations. The values of the entire work needed to deform the alloy Wext, the work used for recoverable deformation Wrec consisting of the elastic deformation energy Wel , the superelastic-like energy Wpt , and the energy of thermoelastic effect Eth , were derived from the Gum Metal stress and temperature vs. strain curves. The irrecoverable mechanical energy Wir expended on plastic deformation, the dissipation energy Q, and finally the stored energy Es were estimated. The stored energy represents a change in the internal energy of the deformed material and is an essential measure of cold-worked state. The Es value turned out to be not large for the Gum Metal, which confirms the alloy low hardening property. The energy components determined for each of the 24 loading cycles enabled us to analyze various stages of the Gum Metal deformation process, including necking and damage. Keywords: gum metal, β-Ti alloy, cyclic tension, superelasticity, energy balance, dissipation, stored energy, infrared thermography Affiliations:
Golasiński K. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Pieczyska E.A. | - | IPPT PAN |
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8. |
Staszczak M., Gradys A.D., Golasiński K.♦, Pieczyska E.A., Polyurethane Shape Memory Polymer: structure characterization and estimation of energy storage and dissipation during tension process,
BULLETIN OF THE POLISH ACADEMY OF SCIENCES: TECHNICAL SCIENCES, ISSN: 0239-7528, DOI: 10.24425/bpasts.2023.147343, Vol.71(6), No.e147343, pp.1-12, 2023Abstract: Shape memory polymers (SMP) are new multifunctional materials that are of increasing interest in various functional applications. Among them, polyurethane shape memory polymers (PU-SMP) are particularly attractive due to their combination of shape memory, high strength and biocompatible properties. Developing new applications for PU-SMP requires comprehensive research on their characteristics. This work involved investigating the structure and mechanical behaviour and characterizing the energy storage and dissipation of a thermoplastic PU-SMP with a glass transition temperature (Tg) of 25 °C during tensile loading-unloading. The process of energy storage and dissipation in the PU-SMP was investigated based on the stress-strain curves recorded by a quasi-static testing machine and the temperature changes, accompanying the deformation process, obtained by using a fast and sensitive infrared camera. The results showed that the thermomechanical behaviour of the examined PU-SMP depends significantly on the strain rate. At a higher strain rate, there are higher stress and related temperature changes, which lead to greater energy dissipation. However, the energy storage values estimated during the deformation process turned out to be not significant, indicating that the work supplied to the PU-SMP structure during loading is mainly converted into heat. It should also be noted that the structural investigation revealed no crystalline phase in the investigated PU-SMP Keywords: shape memory polymer,infrared camera,thermomechanical couplings,energy storage and dissipation,tension test Affiliations:
Staszczak M. | - | IPPT PAN | Gradys A.D. | - | IPPT PAN | Golasiński K. | - | other affiliation | Pieczyska E.A. | - | IPPT PAN |
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9. |
Staszczak M., Nabavian Kalat M., Golasiński K.M., Urbański L., Takeda K.♦, Matsui R.♦, Pieczyska E.A., Characterization of Polyurethane Shape Memory Polymer and Determination of Shape Fixity and Shape Recovery in Subsequent Thermomechanical Cycles,
Polymers, ISSN: 2073-4360, DOI: 10.3390/polym14214775, Vol.14, No.4775, pp.1-19, 2022Abstract: Multifunctional polyurethane shape memory polymers (PU-SMPs) have been of increasing interest in various applications. Here we report structure characterization, detailed methodology, and obtained results on the identification of functional properties of a thermoset PU-SMP (MP4510) with glass transition temperature of 45 C. The stable, chemically crosslinked network of this thermoset PU-SMP results in excellent shape memory behavior. Moreover, the proximity of the activation temperature range of this smart polymer to room and body temperature enables the PU-SMP to be used in more critical industrial applications, namely fast-response actuators. The thermomechanical behavior of a shape memory polymer determines the engineering applications of the material. Therefore, investigation of the shape memory behavior of this class of commercial PU-SMP is of particular importance. The conducted structural characterization confirms its shape memory properties. The shape fixity and shape recovery properties were determined by a modified experimental approach, considering the polymer’s sensitivity to external conditions, i.e., the temperature and humidity variations. Three thermomechanical cycles were considered and the methodology used is described in detail. The obtained shape fixity ratio of the PU-SMP was approximately 98% and did not change significantly in the subsequent cycles of the thermomechanical loading due to the stability of chemical crosslinks in the thermoset materials structure. The shape recovery was found to be approximately 90% in the first cycle and reached a value higher than 99% in the third cycle. The results confirm the effect of the thermomechanical training on the improvement of the PU-SMP shape recovery after the first thermomechanical cycle as well as the effect of thermoset material stability on the repeatability of the shape memory parameters quantities. Keywords: polyurethane shape memory polymer, thermomechanical loading program, shape fixity, shape recovery Affiliations:
Staszczak M. | - | IPPT PAN | Nabavian Kalat M. | - | IPPT PAN | Golasiński K.M. | - | IPPT PAN | Urbański L. | - | IPPT PAN | Takeda K. | - | Aichi Institute of Technology (JP) | Matsui R. | - | Aichi Institute of Technology (JP) | Pieczyska E.A. | - | IPPT PAN |
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10. |
Golasiński K.M., Janiszewski J.♦, Sienkiewicz J.♦, Płociński T.♦, Zubko M.♦, Świec P.♦, Pieczyska E.A., Quasi-static and dynamic compressive behavior of Gum Metal: experiment and constitutive model,
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, ISSN: 1073-5623, DOI: 10.1007/s11661-021-06409-z, pp.1-14, 2021Abstract: The quasi-static and high strain rate compressive behavior of Gum Metal with composition Ti-36Nb-2Ta-3Zr-0.3O (wt pct) has been investigated using an electromechanical testing machine and a split Hopkinson pressure bar, respectively. The stress–strain curves obtained for Gum Metal tested under monotonic and dynamic loadings revealed a strain-softening effect which intensified with increasing strain rate. Moreover, the plastic flow stress was observed to increase for both static and dynamic loading conditions with increasing strain rate. The microstructural characterization of the tested Gum Metal specimens showed particular deformation mechanisms regulating the phenomena of strain hardening and strain softening, namely an adiabatic shear band formed at ~ 45 deg with respect to the loading direction as well as widely spaced deformation bands (kink bands). Dislocations within the channels intersecting with twins may cause strain hardening while recrystallized grains and kink bands with crystal rotation inside the grains may lead to strain softening. A constitutive description of the compressive behavior of Gum Metal was proposed using a modified Johnson–Cook model. Good agreement between the experimental and the numerical data obtained in the work was achieved. Affiliations:
Golasiński K.M. | - | IPPT PAN | Janiszewski J. | - | Military University of Technology (PL) | Sienkiewicz J. | - | Military University of Technology (PL) | Płociński T. | - | Warsaw University of Technology (PL) | Zubko M. | - | other affiliation | Świec P. | - | other affiliation | Pieczyska E.A. | - | IPPT PAN |
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11. |
Golasiński K.M., Detsch R.♦, Szklarska M.♦, Łosiewicz B.♦, Zubko M.♦, Mackiewicz S., Pieczyska E.A., Boccaccini A.R.♦, Evaluation of mechanical properties, in vitro corrosion resistance and biocompatibility of Gum Metal in the context of implant applications,
Journal of the Mechanical Behavior of Biomedical Materials, ISSN: 1751-6161, DOI: 10.1016/j.jmbbm.2020.104289, Vol.115, pp.104289-1-11, 2021Abstract: In recent decades, several novel Ti alloys have been developed in order to produce improved alternatives to the conventional alloys used in the biomedical industry such as commercially pure titanium or dual phase (alpha and beta) Ti alloys. Gum Metal with the non-toxic composition Ti–36Nb–2Ta–3Zr–0.3O (wt. %) is a relatively new alloy which belongs to the group of metastable beta Ti alloys. In this work, Gum Metal has been assessed in terms of its mechanical properties, corrosion resistance and cell culture response. The performance of Gum Metal was contrasted with that of Ti–6Al–4V ELI (extra-low interstitial) which is commonly used as a material for implants. The advantageous mechanical characteristics of Gum Metal, e.g. a relatively low Young's modulus (below 70 GPa), high strength (over 1000 MPa) and a large range of reversible deformation, that are important in the context of potential implant applications, were confirmed. Moreover, the results of short- and long-term electrochemical characterization of Gum Metal showed high corrosion resistance in Ringer's solution with varied pH. The corrosion resistance of Gum Metal was best in a weak acid environment. Potentiodynamic polarization studies revealed that Gum Metal is significantly less susceptible to pitting corrosion compared to Ti–6Al–4V ELI. The oxide layer on the Gum Metal surface was stable up to 8.5 V. Prior to cell culture, the surface conditions of the samples, such as nanohardness, roughness and chemical composition, were analyzed. Evaluation of the in vitro biocompatibility of the alloys was performed by cell attachment and spreading analysis after incubation for 48 h. Increased in vitro MC3T3-E1 osteoblast viability and proliferation on the Gum Metal samples was observed. Gum Metal presented excellent properties making it a suitable candidate for biomedical applications. Keywords: Gum Metal, mechanical behavior, in vitro corrosion resistance, in vitro biocompatibility, implant applications Affiliations:
Golasiński K.M. | - | IPPT PAN | Detsch R. | - | Friedrich-Alexander University of Erlangen-Nürnberg (DE) | Szklarska M. | - | other affiliation | Łosiewicz B. | - | other affiliation | Zubko M. | - | other affiliation | Mackiewicz S. | - | IPPT PAN | Pieczyska E.A. | - | IPPT PAN | Boccaccini A.R. | - | Friedrich-Alexander University of Erlangen-Nürnberg (DE) |
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12. |
Golasiński K.M., Pieczyska E.A., Maj M., Staszczak M., Świec P.♦, Furuta T.♦, Kuramoto S.♦, Investigation of strain rate sensitivity of gum metal under tension using digital image correlation,
ARCHIVES OF CIVIL AND MECHANICAL ENGINEERING, ISSN: 1644-9665, DOI: 10.1007/s43452-020-00055-9, Vol.20, No.2, pp.53-1-14, 2020Abstract: Mechanical behavior of a multifunctional titanium alloy Gum Metal was investigated by conducting tensile tests at various strain rates and applying digital image correlation (DIC) technique. Stress–strain curves confirmed low Young's modulus and high strength of the alloy. The determined values of yield strength had a tendency to increase, whereas the elongation to the specimen rupture tended to decrease with increasing strain rate. True stress versus strain curves were analyzed using selected lengths of virtual extensometer (VE) placed in the strain localization area. When the initial length of the VE was the same as the gauge length, work hardening was observed macroscopically at lower strain rates, and a softening was seen at higher strain rates. However, the softening effect was not observed at the shorter VE lengths. Evolution of the Hencky strain and rate of deformation tensor component fields were analyzed for various strain rates at selected stages of Gum Metal loading. The DIC analysis demonstrated that for lower strain rates the deformation is macroscopically uniform up to the higher average Hencky strains, whereas for higher strain rates the strain localization occurs at the lower average Hencky strains of the deformation process and takes place in the smaller area. It was also found that for all strain rates applied, the maximal values of Hencky strain immediately before rupture of Gum Metal samples were similar for each of the applied strain rates, and the maximal local values of deformation rate were two orders higher when compared to applied average strain rate values. Keywords: titanium alloy, gum metal, strain rate sensitivity, strain localization, digital image correlation, full-field deformation analysis Affiliations:
Golasiński K.M. | - | IPPT PAN | Pieczyska E.A. | - | IPPT PAN | Maj M. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Świec P. | - | other affiliation | Furuta T. | - | Toyota Central Research & Development Laboratories (JP) | Kuramoto S. | - | Ibaraki University Japan (JP) |
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13. |
Golasiński K.M., Pieczyska E.A., Maj M., Mackiewicz S., Staszczak M., Kowalewski Z.L., Urbański L., Zubko M.♦, Takesue N.♦, Anisotropy of gum metal analysed by ultrasonic measurement and digital image correlation,
MATERIALS SCIENCE AND TECHNOLOGY, ISSN: 0267-0836, DOI: 10.1080/02670836.2019.1629539, Vol.36, No.9, pp.996-1002, 2020Abstract: The mechanical anisotropy of a multifunctional titanium alloy, Gum Metal, is investigated in this paper. The structural characterisation showed a strong <110> texture for Gum Metal, that is a result of the cold-swaging process applied during its manufacture. Gum Metal was treated as a transversally isotropic solid because of this texture. A significant difference from Young's moduli of the alloy was detected from the ultrasonic measurement of parallel and perpendicular directions to the alloy swaging direction. Samples of Gum Metal cubes were compressed in two different orientations. During the deformation process, two perpendicular walls of each sample were monitored by two visible range cameras for further two-dimensional digital image correlation analysis, this confirmed a strong plastic anisotropy in Gum Metal. Keywords: gum metal, compression, mechanical anisotropy, digital image correlation, ultrasonic measurement, texture, titanium alloy, full-field deformation measurement Affiliations:
Golasiński K.M. | - | IPPT PAN | Pieczyska E.A. | - | IPPT PAN | Maj M. | - | IPPT PAN | Mackiewicz S. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Kowalewski Z.L. | - | IPPT PAN | Urbański L. | - | IPPT PAN | Zubko M. | - | other affiliation | Takesue N. | - | Fukuoka University (JP) |
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14. |
Kowalczyk-Gajewska K., Pieczyska E.A., Golasiński K.M., Maj M., Kuramoto S.♦, Furuta T.♦, A finite strain elastic-viscoplastic model of gum metal,
International Journal of Plasticity, ISSN: 0749-6419, DOI: 10.1016/j.ijplas.2019.02.017, Vol.119, pp.85-101, 2019Abstract: A hyperelastic-viscoplastic model of Gum Metal is presented. The model is formulated in the large strain framework. The free energy function is postulated consisting of the hyperelastic and viscoplastic components. Original extension of the Neo-Hooke model with a power law component is proposed for hyperelasticity, which enables to describe a relatively large non-linear elastic regime observed for the alloy. Viscoplastic strain follows the Perzyna-type law with an overstress function. The model is implemented into the finite element method and used to simulate the Gum Metal response in multiple tension loading-unloading cycles. The results are compared with experimental outcomes. Good accordance of the simulation results and the available experimental data is obtained. Keywords: large strain, hyperelasto-viscoplasticity, gum metal, cyclic deformation Affiliations:
Kowalczyk-Gajewska K. | - | IPPT PAN | Pieczyska E.A. | - | IPPT PAN | Golasiński K.M. | - | IPPT PAN | Maj M. | - | IPPT PAN | Kuramoto S. | - | Ibaraki University Japan (JP) | Furuta T. | - | Toyota Central Research & Development Laboratories (JP) |
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15. |
Dunić V.♦, Pieczyska E.A., Kowalewski Z.L., Matsui R.♦, Slavković R.♦, Experimental and numerical investigation of mechanical and thermal effects in TiNi SMA during transformation-induced creep phenomena,
Materials, ISSN: 1996-1944, DOI: 10.3390/ma12060883, Vol.12, No.6, pp.883-1-13, 2019Abstract: The paper presents experimental and numerical results of the TiNi shape memory alloy (SMA) subjected to a modified program of force-controlled tensile loading. The time-dependent development of transformation strain under the constant-force conditions was investigated to describe transformation-induced creep phenomena. (2) Mechanical characteristics of the TiNi SMA were derived using a testing machine, whereas the SMA temperature changes accompanying its deformation were obtained in a contactless manner with an infrared camera. A 3D coupled thermo-mechanical numerical analysis, realized in a partitioned approach, was applied to describe the SMA mechanical and thermal responses. (3) The stress and related temperature changes demonstrated how the transformation-induced creep process started and evolved at various stages of the SMA loading. The proposed model reproduced the stress, strain and temperature changes obtained during the experiment well; the latent heat production is in correlation with the amount of the martensitic volume fraction. (4) It was demonstrated how the transformation-induced creep process occurring in the SMA under such conditions was involved in thermo-mechanical couplings and the related temperature changes. Keywords: TiNi shape memory alloy, phase transformation-induced creep, martensitic transformation, temperature change, thermomechanical couplings, infrared camera, thermo-mechanical coupled numerical analysis Affiliations:
Dunić V. | - | University of Kragujevac (XS) | Pieczyska E.A. | - | IPPT PAN | Kowalewski Z.L. | - | IPPT PAN | Matsui R. | - | Aichi Institute of Technology (JP) | Slavković R. | - | University of Kragujevac (XS) |
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16. |
Pieczyska E.A., Golasiński K.M., Maj M., Furuta T.♦, Kuramoto S.♦, Development of strain localization in a beta-titanium alloy gum metal analyzed by infrared camera and digital image correlation for various strain rates,
Proceedings — Open Access Journal, ISSN: 2504-3900, DOI: 10.3390/proceedings2019027051, Vol.27, No.1, pp.51-1-4, 2019Abstract: Effects of thermomechanical couplings were studied in a new beta Ti alloy by IR and DIC techniques. The obtained stress-strain curves confirmed low Young’s modulus and high strength of the alloy. The determined values of yield strength increases and values of elongation till rupture decreases with increasing strain rate. It was found, by using fast and sensitive infrared camera, that the large limit of the Gum Metal reversible nonlinear deformation originates from mechanisms of dissipative nature, probably exothermic stress-induced transition of α" nanodomains. Keywords: titanium alloy, gum metal, strain rate, infrared camera, temperature change, DIC Affiliations:
Pieczyska E.A. | - | IPPT PAN | Golasiński K.M. | - | IPPT PAN | Maj M. | - | IPPT PAN | Furuta T. | - | Toyota Central Research & Development Laboratories (JP) | Kuramoto S. | - | Ibaraki University Japan (JP) |
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17. |
Pieczyska E.A., Golasiński K.M., Maj M., Staszczak M., Kowalewski Z.L., Furuta T.♦, Kuramoto S.♦, Yielding and strain localization effects in gum metal - a unique Ti alloy - investigated by digital image correlation and infrared thermography,
Materials Today: Proceedings, ISSN: 2214-7853, DOI: 10.1016/j.matpr.2019.03.119, Vol.12, pp.235-238, 2019Abstract: The research concerns investigation of yielding and developing of the strain localization in new β-Ti alloy characterized by unique elastic-plastic properties, named Gum Metal. The alloy was subjected to tension on testing machine at three various strain rates up to rupture. Digital image correlation and infrared thermography were applied to analyze the experimental results. Strain distributions were determined on the basis of digital image correlation algorithm. The related temperature variations were found in contactless manner using infrared thermography. Mechanical and the corresponding thermal data were used to study the Gum Metal large nonlinear reversible deformation and localization effects. Keywords: gum metal, tension, large nonlinear elastic deformation, thermomechanical couplings, temperature change, digital image correlation Affiliations:
Pieczyska E.A. | - | IPPT PAN | Golasiński K.M. | - | IPPT PAN | Maj M. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Kowalewski Z.L. | - | IPPT PAN | Furuta T. | - | Toyota Central Research & Development Laboratories (JP) | Kuramoto S. | - | Ibaraki University Japan (JP) |
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18. |
Pieczyska E.A., Maj M., Golasiński K.M., Staszczak M., Furuta T.♦, Kuramoto S.♦, Thermomechanical Studies of Yielding and Strain Localization Phenomena of Gum Metal under Tension,
Materials, ISSN: 1996-1944, DOI: 10.3390/ma11040567, Vol.11, No.567, pp.1-13, 2018Abstract: This paper presents results of investigation of multifunctional beta-Ti alloy Gum Metal subjected to tension at various strain rates. Digital image correlation was used to determine strain distributions and stress-strain curves, while infrared camera allowed for us to obtain the related temperature characteristics of the specimen during deformation. The mechanical curves completed by the temperature changes were applied to analyze the subsequent stages of the alloy loading. Elastic limit, recoverable strain, and development of the strain localization were studied. It was found that the maximal drop in temperature, which corresponds to the yield limit of solid materials, was referred to a significantly lower strain value in the case of Gum Metal in contrast to its large recoverable strain. The temperature increase proves a dissipative character of the process and is related to presence of w and a” phases induced during the alloy fabrication and their exothermic phase transformations activated under loading. During plastic deformation, both the strain and temperature distributions demonstrate that strain localization for higher strain rates starts nucleating just after the yield limit leading to specimen necking and rupture. Macroscopically, it is exhibited as softening of the stress-strain curve in contrast to the strain hardening observed at lower strain rates. Keywords: gum metal, yield limit, thermomechanical coupling, infrared thermography, digital image correlation, strain localization Affiliations:
Pieczyska E.A. | - | IPPT PAN | Maj M. | - | IPPT PAN | Golasiński K.M. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Furuta T. | - | Toyota Central Research & Development Laboratories (JP) | Kuramoto S. | - | Ibaraki University Japan (JP) |
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19. |
Matsui R.♦, Takeda K.♦, Tobushi H.♦, Pieczyska E.A., Mechanical properties and advanced subjects in shape memory alloys and polymers,
JOURNAL OF THEORETICAL AND APPLIED MECHANICS, ISSN: 1429-2955, DOI: 10.15632/jtam-pl.56.2.447, Vol.56, No.2, pp.447-456, 2018Abstract: Advanced subjects in mechanical properties of shape memory alloys and polymers are discussed. In the subloop loading under a stress-controlled condition of the shape memory alloy, the transformation-induced stress relaxation appears due to variation in temperature. The enhancement of corrosion and corrosion fatigue life of the shape memory alloy is discussed. The development of a functionally-graded shape memory alloy and polymer is expected to obtain better performance. Three-way motion appears in the shape memory composite with the shape memory alloy and polymer. Keywords: shape memory alloy, shape memory polymer, functionally-graded shape memory material, shape memory composite Affiliations:
Matsui R. | - | Aichi Institute of Technology (JP) | Takeda K. | - | Aichi Institute of Technology (JP) | Tobushi H. | - | Aichi Institute of Technology (JP) | Pieczyska E.A. | - | IPPT PAN |
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20. |
Pieczyska E.A., Staszczak M., Kowalczyk-Gajewska K., Maj M., Golasiński K.M., Golba S.♦, Tobushi H.♦, Hayashi S.♦, Experimental and numerical investigation of yielding phenomena in a shape memory polymer subjected to cyclic tension at various strain rates,
POLYMER TESTING, ISSN: 0142-9418, DOI: 10.1016/j.polymertesting.2017.04.014, Vol.60, pp.333-342, 2017Abstract: This paper presents experimental and numerical results of a polyurethane shape memory polymer (SMP) subjected to cyclic tensile loading. The goal was to investigate the polymer yielding phenomena based on the effects of thermomechanical coupling. Mechanical characteristics were obtained with a testing machine, whereas the SMP temperature accompanying its deformation process was simultaneously measured in a contactless manner with an infrared camera. The SMP glass transition temperature was approximately 45oC; therefore, when tested at room temperature, the polymer is rigid and behaves as solid material. The stress and related temperature changes at various strain rates showed how the SMP yield limit evolved in subsequent loading-unloading cycles under various strain rates. A two-phase model of the SMP was applied to describe its mechanical response in cyclic tension. The 3D Finite Element model of a tested specimen was used in simulations. Good agreement between the model predictions and experimental results was observed for the first tension cycle. Keywords: Shape memory polymer, Tension cyclic loading, Thermomechanical coupling, Yield limit, Thermoelastic effect, Constitutive model Affiliations:
Pieczyska E.A. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Kowalczyk-Gajewska K. | - | IPPT PAN | Maj M. | - | IPPT PAN | Golasiński K.M. | - | IPPT PAN | Golba S. | - | University of Silesia (PL) | Tobushi H. | - | Aichi Institute of Technology (JP) | Hayashi S. | - | SMP Technologies Inc. (JP) |
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21. |
Takeda K.♦, Matsui R.♦, Tobushi H.♦, Pieczyska E.A., Torsional deformation properties of SMA tapes and their application to bias-type reciprocating rotary driving actuator,
ARCHIVES OF MECHANICS, ISSN: 0373-2029, Vol.69, No.4-5, pp.289-303, 2017Abstract: In order to develop the reciprocating rotary driving actuator with a simple mechanism using shape memory alloy (SMA) tapes, the graphical method to design the actuator was proposed based on the torsional deformation properties of SMA tapes. The torsional deformation properties of the SME tape showing the shape memory effect (SME) and the SE tape showing superelasticity (SE) were obtained. The bias-type reciprocating rotary actuator was composed of the pretwisted SME tape and the flat SE tape in series. The design chart expressed by the relationship between torque and twisting angle of the SME tape and the SE tape was proposed. The rotational angle and torque, which vary depending on temperature, can be estimated based on the design chart. The rotational angle is controlled by adjusting the mounting angle of the SME tape and the heating temperature. The automatically opening and closing blind driven by sunlight was demonstrated. The blind was controlled by using the reciprocating rotary element composed of the SME tape and the SE tape. The behavior of the blind can be achieved based on the proposed design method of the reciprocating rotary driving element Keywords: shape memory alloy, tape, torsion, actuator, reciprocating rotation, design chart, bias-type Affiliations:
Takeda K. | - | Aichi Institute of Technology (JP) | Matsui R. | - | Aichi Institute of Technology (JP) | Tobushi H. | - | Aichi Institute of Technology (JP) | Pieczyska E.A. | - | IPPT PAN |
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22. |
Golasiński K.M., Pieczyska E.A., Staszczak M., Maj M., Furuta T.♦, Kuramoto S.♦, Infrared thermography applied for experimental investigation of thermomechanical couplings in Gum Metal,
Quantitative InfraRed Thermography Journal, ISSN: 1768-6733, DOI: 10.1080/17686733.2017.1284295, Vol.14, No.2, pp.1-8, 2017Abstract: Results of initial investigation of thermomechanical couplings in innovative β-Ti alloy called Gum Metal subjected to tension are presented. The experimental set-up, consisting of testing machine and infrared camera, enabled to obtain stress–strain curves with high accuracy and correlate them to estimated temperature changes of the specimen during the deformation process. Both ultra-low elastic modulus and high strength of Gum Metal were confirmed. The infrared measurements determined average and maximal temperature changes accompanying the alloy deformation process, allowed to estimate thermoelastic effect, which is related to the alloy yield point. The temperature distributions on the specimen surface served to analyse strain localization effects leading to the necking and rupture. Keywords: gum metal, thermomechanical coupling, nonlinear elasticity, yield point, infrared camera Affiliations:
Golasiński K.M. | - | IPPT PAN | Pieczyska E.A. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Maj M. | - | IPPT PAN | Furuta T. | - | Toyota Central Research & Development Laboratories (JP) | Kuramoto S. | - | Ibaraki University Japan (JP) |
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23. |
Pieczyska E.A., Kowalewski Z.L., Dunic V.Lj.♦, Stress Relaxation Effects in TiNi SMA During Superelastic Deformation: Experiment and Constitutive Model,
SHAPE MEMORY and SUPERELASTICITY, ISSN: 2199-384X, DOI: 10.1007/s40830-017-0123-2, Vol.2017, No.3, pp.392-402, 2017Abstract: This paper presents an investigation of thermomechanical effects related to the phenomena of stress relaxation occurring in TiNi SMA subjected to modified program of displacement-controlled tension. The deformation data were taken from testing machine, whereas the temperature changes accompanying the exothermic/endothermic martensite forward/reverse transformation were measured by infrared camera. At the advanced stages of the transformations, the strain was kept constant for a few minutes and the SMA load and temperature were recorded continuously. As a consequence, the stress and temperature changed significantly during the loading stops. A large stress drop, caused by the transformation, was observed during the relaxation stage in both courses of the SMA loading and unloading. Moreover, the non-uniform temperature distribution, reflecting macroscopically inhomogeneous transformation, lapsed while the strain was kept constant, yet restarted at the end of the relaxation stop and developed at the reloading stage. Along with the experimental results, the mechanical and thermal responses induced by the transformation were obtained by 3D coupled thermomechanical numerical analysis, realized in partitioned approach. Latent heat production was correlated with an amount of the martensitic volume fraction. The stress and temperature drops recorded during the experiment were satisfactorily reproduced by the model proposed for the SMA thermomechanical coupling Keywords: TiNi shape memory alloy, Superelasticity, Stress relaxation, Temperature change, Thermomechanical couplings, 3-D model Affiliations:
Pieczyska E.A. | - | IPPT PAN | Kowalewski Z.L. | - | IPPT PAN | Dunic V.Lj. | - | University of Kragujevac (XS) |
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24. |
Pieczyska E.A., Staszczak M., Maj M., Kowalczyk-Gajewska K., Golasiński K.M., Cristea M.♦, Tobushi H.♦, Hayashi S.♦, Investigation of thermomechanical couplings, strain localization and shape memory properties in a shape memory polymer subjected to loading at various strain rates,
SMART MATERIALS AND STRUCTURES, ISSN: 0964-1726, DOI: 10.1088/0964-1726/25/8/085002, Vol.25, No.8, pp.085002-1-15, 2016Abstract: This paper presents experimental and modeling results of the effects of thermomechanical couplings occurring in a polyurethane shape memory polymer (SMP) subjected to tension at various strain rates within large strains. The SMP mechanical curves, recorded using a testing machine, and the related temperature changes, measured in a contactless manner using an IR camera, were used to investigate the polymer deformation process at various loading stages. The effects of thermomechanical couplings allowed the determination of the material yield point in the initial loading stage, the investigation of nucleation and development of the strain localization at larger strains and the estimation of the effects of thermoelastic behavior during the unloading process. The obtained stress–strain and thermal characteristics, the results of the dynamic mechanical analysis and estimated values of the shape fixity and shape recovery parameters confirmed that the shape memory polymer (T g = 45°C) is characterized by good mechanical and shape memory properties, as well as high sensitivity to the strain rate. The mechanical response of the SMP subjected to tension was simulated using the finite element method and applying the large strain, two-phase model. Strain localization observed in the experiment was well reproduced in simulations and the temperature spots were correlated with the accumulated viscoplastic deformation of the SMP glassy phase. Keywords: shape memory polymer, thermomechanical coupling, infrared camera, tension test, strain rate, strain localization, constitutive model Affiliations:
Pieczyska E.A. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Maj M. | - | IPPT PAN | Kowalczyk-Gajewska K. | - | IPPT PAN | Golasiński K.M. | - | IPPT PAN | Cristea M. | - | Petru Poni Institute of Macromolecular Chemistry (RO) | Tobushi H. | - | Aichi Institute of Technology (JP) | Hayashi S. | - | SMP Technologies Inc. (JP) |
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25. |
Staszczak M., Pieczyska E.A., Maj M., Kukla D., Tobushi H.♦, Infrared thermographic analysis of shape memory polymer during cyclic loading,
MEASUREMENT SCIENCE AND TECHNOLOGY, ISSN: 0957-0233, DOI: 10.1088/0957-0233/27/12/124007, Vol.27, No.12, pp.124007-1-6, 2016Abstract: In this paper we present the effects of thermomechanical couplings occurring in polyurethane shape memory polymer subjected to cyclic tensile loadings conducted at various strain rates. Stress–strain characteristics were elaborated using a quasistatic testing machine, whereas the specimen temperature changes accompanying the deformation process were obtained with an infrared camera. We demonstrate a tight correlation between the mechanical and thermal results within the initial loading stage. The polymer thermomechanical behaviour in four subsequent loading-unloading cycles and the influence of the strain rate on the stress and the related temperature changes were also examined. In the range of elastic deformation the specimen temperature drops below the initial level due to thermoelastic effect whereas at the higher strains the temperature always increased, due to the dissipative deformation mechanisms. The difference in the characteristics of the specimen temperature has been applied to determine a limit of the polymer reversible deformation and analyzed for various strain rates. It was shown that at the higher strain rates higher values of the stress and temperature changes are obtained, which are related to higher values of the polymer yield points. During the cyclic loading a significant difference between the first and the second cycle was observed. The subsequent loading-unloading cycles demonstrated similar sharply shaped stress and temperature profiles and gradually decrease in values. Keywords: thermomechanical couplings, infrared camera, shape memory polymer, tension, strain rate, thermoelastic effect, yield point Affiliations:
Staszczak M. | - | IPPT PAN | Pieczyska E.A. | - | IPPT PAN | Maj M. | - | IPPT PAN | Kukla D. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) |
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26. |
Pieczyska E.A., Maj M., Kowalczyk-Gajewska K., Staszczak M., Gradys A., Majewski M., Cristea M.♦, Tobushi H.♦, Hayashi S.♦, Thermomechanical properties of polyurethane shape memory polymer–experiment and modelling,
SMART MATERIALS AND STRUCTURES, ISSN: 0964-1726, DOI: 10.1088/0964-1726/24/4/045043, Vol.24, pp.045043-1-16, 2015Abstract: In this paper extensive research on the polyurethane shape memory polymer (PU-SMP) is reported, including its structure analysis, our experimental investigation of its thermomechanical properties and its modelling. The influence of the effects of thermomechanical couplings on the SMP behaviour during tension at room temperature is studied using a fast and sensitive infrared camera. It is shown that the thermomechanical behaviour of the SMP significantly depends on the strain rate: at a higher strain rate higher stress and temperature values are obtained. This indicates that an increase of the strain rate leads to activation of different deformation mechanisms at the micro-scale, along with reorientation and alignment of the molecular chains. Furthermore, influence of temperature on the SMP's mechanical behaviour is studied. It is observed during the loading in a thermal chamber that at the temperature 20°C below the glass transition temperature (Tg) the PU-SMP strengthens about six times compared to the material above Tg but does not exhibit the shape recovery. A finite-strain constitutive model is formulated, where the SMP is described as a two-phase material composed of a hyperelastic rubbery phase and elastic-viscoplastic glassy phase. The volume content of phases is governed by the current temperature. Finally, model predictions are compared with the experimental results. Keywords: shape memory polyurethane, thermomechanical couplings, infrared camera, temperature change, dynamic mechanical analysis, strain rate, constitutive model Affiliations:
Pieczyska E.A. | - | IPPT PAN | Maj M. | - | IPPT PAN | Kowalczyk-Gajewska K. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Gradys A. | - | IPPT PAN | Majewski M. | - | IPPT PAN | Cristea M. | - | Petru Poni Institute of Macromolecular Chemistry (RO) | Tobushi H. | - | Aichi Institute of Technology (JP) | Hayashi S. | - | SMP Technologies Inc. (JP) |
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27. |
Pieczyska E.A., Mechanical behavior and infrared imaging of ferromagnetic NiFeGaCo SMA single crystal subjected to subsequent compression cycles,
MECCANICA, ISSN: 0025-6455, DOI: 10.1007/s11012-013-9868-7, Vol.50, pp.585-590, 2015Abstract: In this paper, an experimental study of thermomechanical coupling related to pseudoelastic deformation of ferromagnetic shape memory alloy (FSMA) is presented. NiFeGaCo single crystal was subjected to subsequent loading–unloading compression cycles. The stress–strain parameters were recorded by mechanical and laser extensometers. Fast and sensitive infrared camera was used in order to record infrared radiation emitted by the sample surface during the deformation process and to calculate temperature changes related to both exothermic forward and endothermic reverse martensitic transformations. Thanks to the applied techniques, we could investigate a nucleation and development of the stress-induced martensitic transformation. The obtained thermograms exposure localized character of the transformation, initiating in form of inclined bands of higher temperature and developing throughout the sample. The elaborated average temperature change of the SMA sample surface reflects an instantaneous rate of the transformation development. High repeatability of both mechanical and temperature changes obtained in the subsequent loading cycles indicates good thermomechanical properties of the FSMA crystal and confirms high accuracy of the measurement. Keywords: Ferromagnetic shape memory alloy, NiFeGaCo, Phase transformation, Transformation bands, Mechanical properties, Compression test, Cyclic loading, Infrared camera, Temperature change, Thermomechanical coupling Affiliations:
Pieczyska E.A. | - | IPPT PAN |
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28. |
Pieczyska E.A., Staszczak M., Maj M., Tobushi H.♦, Hayashi S.♦, Investigation of thermal effects accompanying tensile deformation of Shape Memory Polymer PU-SMP,
Measurement Automation Monitoring, ISSN: 0032-4140, Vol.61, No.6, pp.203-205, 2015Abstract: Experimental results of effects of thermomechanical couplings occurring in shape memory polymer subjected to tension are presented. Stress-strain curves were recorded by testing machine, while their related temperature changes were measured with infrared camera. The mechanical and thermal characteristics were used to investigate the polymer properties. Three various stages were distinguished during the deformation process. The first, elastic, is accompanied by a drop in the specimen temperature; the second, plastic, is associated with change of the material structure and the temperature increase; the third stage, related to the specimen rupture and damage mechanisms, is accompanied by the significant increase in temperature. Keywords: shape memory polymer, tension, thermomechanical coupling, temperature change, infrared camera Affiliations:
Pieczyska E.A. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Maj M. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) | Hayashi S. | - | SMP Technologies Inc. (JP) |
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29. |
Staszczak M., Pieczyska E.A., Maj M., Urbański L., Odriozola I.♦, Martin R.♦, Thermomechanical Properties of Vulcanized Rubber investigated by Testing Machine and Infrared Camera,
Measurement Automation Monitoring, ISSN: 0032-4140, Vol.61, No.6, pp.206-209, 2015Abstract: Experimental results of effects of thermomechanical couplings occurring both in natural vulcanized rubber and rubber with self-healing polyurethane subjected to tension at different strain rates are presented. Mechanical characteristics were recorded by testing machine, while the sample temperature changes accompanying the deformation process was measured by infrared camera. The goal was to investigate influence of self-healing polyurethane on the rubber mechanical and thermomechanical properties. It was found that the introduction of the self-healing polyurethane ensures the higher elasticity and the lower tensile strength of the rubber. It was also confirmed that the material is very sensitive to the strain rate; the higher the strain rate, the higher the values of the stress and temperature increases have been obtained. Keywords: vulcanized rubber, self-healing polyurethane, tension test, thermomechanical couplings, temperature changes, infrared camera Affiliations:
Staszczak M. | - | IPPT PAN | Pieczyska E.A. | - | IPPT PAN | Maj M. | - | IPPT PAN | Urbański L. | - | IPPT PAN | Odriozola I. | - | IK4-CIDETEC (ES) | Martin R. | - | IK4-CIDETEC (ES) |
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30. |
Dunić V.♦, Pieczyska E.A., Tobushi H.♦, Staszczak M., Slavković R.♦, Experimental and numerical thermo-mechanical analysis of shape memory alloy subjected to tension with various stress and strain rates,
SMART MATERIALS AND STRUCTURES, ISSN: 0964-1726, DOI: 10.1088/0964-1726/23/5/055026, Vol.23, pp.055026-1-11, 2014Abstract: TiNi shape memory alloy (SMA) is experimentally and numerically investigated in tension tests under different loading rates. The thermomechanical behaviour of the SMA, related to the stress-induced martensitic transformation (SIMT) noticed during the experimental tests, is analysed and the observations are considered for numerical analysis. Initiation, development and saturation of the SIMT are monitored by a fast and sensitive infrared camera. The estimated temperature changes of the SMA sample, related to the exothermic martensitic forward and endothermic reverse transformation, have been analysed with the focus on the rate-dependent response and on the influence of the heat transfer on the mechanical behaviour. The effectively modified constitutive model, proposed by Lagoudas, is implemented in structural PAK finite element method (FEM) software and is thermomechanically coupled with the heat transfer FEM software in a partitioned approach. The experimental results are quantitatively and qualitatively reproduced by the numerical FEM model, which verifies the efficiency and accuracy of the proposed investigation method. Keywords: shape memory alloy, stressinduced martensitic transformation, modelling, TiNi, tension, infrared camera, temperature changes Affiliations:
Dunić V. | - | University of Kragujevac (XS) | Pieczyska E.A. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) | Staszczak M. | - | IPPT PAN | Slavković R. | - | University of Kragujevac (XS) |
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31. |
Takeda K.♦, Matsui R.♦, Tobushi H.♦, Pieczyska E.A., Transformation-Induced Relaxation and Stress Recovery of TiNi Shape Memory Alloy,
Materials, ISSN: 1996-1944, DOI: 10.3390/ma7031912, Vol.7, pp.1912-1926, 2014Abstract: The transformation-induced stress relaxation and stress recovery of TiNi shape memory alloy (SMA) in stress-controlled subloop loading were investigated based on the local variation in temperature and transformation band on the surface of the tape in the tension test. The results obtained are summarized as follows. (1) In the loading process, temperature increases due to the exothermic martensitic transformation (MT) until the holding strain and thereafter temperature decreases while holding the strain constant, resulting in stress relaxation due to the MT; (2) In the unloading process, temperature decreases due to the endothermic reverse transformation until the holding strain and thereafter temperature increases while holding the strain constant, resulting in stress recovery due to the reverse transformation; (3) Stress varies markedly in the initial stage followed by gradual change while holding the strain constant; (4) If the stress rate is high until the holding strain in the loading and unloading processes, both stress relaxation and stress recovery are large; (5) It is important to take into account this behavior in the design of SMA elements, since the force of SMA elements varies even if the atmospheric temperature is kept constant. Keywords: shape memory alloy, superelasticity, titanium-nickel alloy, subloop, stress relaxation, stress recovery, martensitic transformation Affiliations:
Takeda K. | - | Aichi Institute of Technology (JP) | Matsui R. | - | Aichi Institute of Technology (JP) | Tobushi H. | - | Aichi Institute of Technology (JP) | Pieczyska E.A. | - | IPPT PAN |
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32. |
Pieczyska E.A., Maj M., Kowalczyk-Gajewska K., Staszczak M., Urbański L., Tobushi H.♦, Hayashi S.♦, Cristea M.♦, Mechanical and Infrared Thermography Analysis of Shape Memory Polyurethane,
Journal of Materials Engineering and Performance, ISSN: 1059-9495, DOI: 10.1007/s11665-014-0963-2, Vol.23, No.7, pp.2553-2560, 2014Abstract: Multifunctional new material—polyurethane shape memory polymer (PU-SMP)—was subjected to tension carried out at room temperature at various strain rates. The influence of effects of thermomechanical couplings on the SMP mechanical properties was studied, based on the sample temperature changes, measured by a fast and sensitive infrared camera. It was found that the polymer deformation process strongly depends on the strain rate applied. The initial reversible strain is accompanied by a small drop in temperature, called thermoelastic effect. Its maximal value is related to the SMP yield point and increases upon increase of the strain rate. At higher strains, the stress and temperature significantly increase, caused by reorientation of the polymer molecular chains, followed by the stress drop and its subsequent increase accompanying the sample rupture. The higher strain rate, the higher stress, and temperature changes were obtained, since the deformation process was more dynamic and has occurred in almost adiabatic conditions. The constitutive model of SMP valid in finite strain regime was developed. In the proposed approach, SMP is described as a two-phase material composed of hyperelastic rubbery phase and elastic-viscoplastic glassy phase, while the volume content of phases is specified by the current temperature. Keywords: constitutive model, dynamic mechanical analysis, shape memory polyurethane, strain rate, temperature change, thermomechanical couplings Affiliations:
Pieczyska E.A. | - | IPPT PAN | Maj M. | - | IPPT PAN | Kowalczyk-Gajewska K. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Urbański L. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) | Hayashi S. | - | SMP Technologies Inc. (JP) | Cristea M. | - | Petru Poni Institute of Macromolecular Chemistry (RO) |
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33. |
Pieczyska E.A., Staszczak M., Dunić V.♦, Slavković R.♦, Tobushi H.♦, Takeda K.♦, Development of Stress-Induced Martensitic Transformation in TiNi Shape Memory Alloy,
Journal of Materials Engineering and Performance, ISSN: 1059-9495, DOI: 10.1007/s11665-014-0959-y, Vol.23, No.7, pp.2505-2514, 2014Abstract: TiNi shape memory alloy (SMA) was subjected to tension at strain-controlled test on quasistatic testing machine. The nucleation, development, and saturation of the stress-induced martensitic transformation were investigated, taking into account the obtained dependency of mechanical parameters and the specimen temperature changes measured by an infrared camera (IR). Three kinds of data obtained by the IR system were analyzed: the temperature distribution on the SMA sample surface, the temperature changes derived as average from the chosen sample area, and the temperature profiles obtained along the sample length. The temperature distribution shows nucleation of the transformation process and a creation of the transformation bands. The average temperature reflects the effects of thermomechanical coupling, accompanying exothermic martensitic forward and endothermic reverse transformation. The temperature profiles revealed the temperature difference between the band and the rest of the sample. The experimental results were supported with finite element method numerical analysis (FEM). The FEM software components for structural and heat transfer problems, coupled in partitioned approach, were used for thermomechanical analysis. Keywords: finite element modeling, infrared camera, material testing, martensitic transformation, TiNi shape memory alloy, tension, thermomechanical couplings Affiliations:
Pieczyska E.A. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Dunić V. | - | University of Kragujevac (XS) | Slavković R. | - | University of Kragujevac (XS) | Tobushi H. | - | Aichi Institute of Technology (JP) | Takeda K. | - | Aichi Institute of Technology (JP) |
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34. |
Pieczyska E.A., Thermomechanical aspects of the nucleation and development of stress-induced martensitic transformation in shape memory alloys,
Annual Report - Polish Academy of Sciences, ISSN: 1640-3754, Vol.2014, pp.74-77, 2014Abstract: Due to the dynamic development of technology and the increasing demand for materials, as well as growing environmental awareness, particular interest has recently been focused on multifunctional smart materials, able serve various purposes, such as working, sensing, and crack-healing. This group includes shape memory materials: alloys, polymers and composites. Among these, shape memory alloys (SMAs) have attracted an especially high level of attention because of their unique properties, such as the shape memory eG ect and superelasticity, related to large recovery strain, stress, and energy storage and dissipation, which are important for their application as actuators, elements of dampers, or earthquake protection systems. The SMA properties are caused by a stress- or temperature-induced crystallographically reversible martensitic transformation between a high-symmetry austenite and a low-symmetry martensite structure, related to changes in shape and size. These properties, together with high sensitivity to temperature, allow the SMA to combine sensor and actuator functions, thus enabling miniaturization and various applications in biomedicine (cardiosurgical stents, guidewires, orthodontic braces), aircraft (joining elements, morphing), spacecraft (automatic doors), and the car and housing industries (sensors and actuators, conditioners, overheating protectors). In order to design shape memory elements for an application, thermomechanical properties are very important (Tobushi et al., 2013). Such research has been carried out for years at the Institute of Fundamental Technological Research (IFTR): thermodynamic description by B. Raniecki, and A. Ziółkowski, micromechanics by H. Petryk and S. Stupkiewicz, as well as the experimental approach coordinated by W. K. Nowacki and L. Dietrich in collaboration with their Japanese partners S. Miyazaki and H. Tobushi. The results obtained using an infrared camera have turned out to be especially interesting, including for researchers from other centers. the high sensitivity (0.025K) and frequency (538Hz) of the camera, and most importantly the long tradition and extensive experience of the IFTR in experimental research on thermomechanical couplings in metals, all contributed to unique results on SMA properties being obtained. Keywords: shape memory alloy, infrared camera, localised transformation Affiliations:
Pieczyska E.A. | - | IPPT PAN |
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35. |
Pieczyska E.A., Kowalczyk-Gajewska K., Maj M., Staszczak M., Tobushi H.♦, Thermomechanical investigation of TiNi shape memory alloy and PU shape memory polymer subjected to cyclic loading,
Procedia Engineering, ISSN: 1877-7058, DOI: 10.1016/j.proeng.2014.06.264, Vol.74, pp.287-292, 2014Abstract: In applications to sensors, actuators, guide wires, special grips for handicapped people, a shape memory alloy (SMA) or shape memory polymer (SMP) are used as working elements that perform cyclic motions. In order to evaluate the reliability of the shape memory materials (SMM), cycling and fatigue deformation properties are investigated. Since the SMM are very sensitive to temperature, not only mechanical properties but also their related temperature changes accompanying the deformation process should be taken into account. The presented paper embraces experimental investigation of effects of thermomechanical couplings occurring in shape memory alloy and shape memory polymer subjected to various kinds of cycling loading. The deformation was carried out on MTS 858 Testing machine. The strain was measured by a mechanical extensometer, so the stress-strain characteristics were elaborated with high accuracy. Furthermore, a fast and sensitive FLIR Co Phoenix infrared (IR) measurement system was used in order to record infrared radiation from the sample surface. It enables obtaining temperature distribution of the sample as a function of the deformation parameters. For each strain cycle, an increase in temperature during the loading and the temperature decrease during the unloading processes was observed. It was found that the temperature increment recorded during the cyclic deformation depends on the strain rate, the kind of the material and the test conditions. The higher the strain rate the higher the stress and temperature changes were obtained, since the deformation process was more dynamic and has occurred in almost adiabatic conditions. It was shown that various deformation mechanisms are active during various loading stages. Keywords: shape memory alloy, shape memory polymer, cyclic deformation, thermomechanical coupling, infrared camera Affiliations:
Pieczyska E.A. | - | IPPT PAN | Kowalczyk-Gajewska K. | - | IPPT PAN | Maj M. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) |
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36. |
Pieczyska E.A., Tobushi H.♦, Kulasiński K., Development of transformation bands in TiNi SMA for various stress and strain rates studied by a fast and sensitive infrared camera,
SMART MATERIALS AND STRUCTURES, ISSN: 0964-1726, DOI: 10.1088/0964-1726/22/3/035007, Vol.22, No.3, pp.035007-1-8, 2013Abstract: TiNi shape memory alloy (SMA) was subjected to tension at various strain rates for stress- and strain-controlled tests. The nucleation, development and saturation of the stress-induced martensitic transformation were investigated, based on the specimen temperature changes, measured by a fast and sensitive infrared camera. It was found that the initial, macroscopically homogeneous phase transformation occurs at the same stress level for all strain rates applied, regardless of the loading manner, while the stress of the localized transformation increases with the strain rate. At higher strain rate, a more dynamic course of the transformation process was observed, revealed in the creation of numerous fine transformation bands. An inflection point was noticed on the stress–strain curve, dividing the transformation range into two stages: the first heterogeneous, where transformation bands nucleate and evolve throughout the sample; the second, where the bands overlap, related to significant temperature increase and an upswing region of the curve. In the final part of the SMA loading a decrease of the average sample temperature revealed the saturation stage of the transformation. It was also observed that nucleation of the localized martensitic forward transformation takes place in the weakest area of the sample in both approaches, whereas the reverse transformation always initiates in its central part. Keywords: shape memory alloy, various strain rates, stress- and strain-controlled tests, stress-induced martensitic transformation, fast and sensitive infrared camera, transformation bands, localized martensitic forward transformation, reverse transformation Affiliations:
Pieczyska E.A. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) | Kulasiński K. | - | IPPT PAN |
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37. |
Tobushi H.♦, Pieczyska E.A., Miyamoto K.♦, Mitsui K.♦, Torsional deformation characteristics of TiNi SMA tape and application to rotary actuator,
JOURNAL OF ALLOYS AND COMPOUNDS, ISSN: 0925-8388, DOI: 10.1016/j.jallcom.2011.10.108, Vol.577S, pp.S745-S748, 2013Abstract: In order to develop novel shape memory actuators, the torsional deformation of a shape memory alloy (SMA) tape and the actuator models driven by the tape were investigated. The results obtained can be summarized as follows. In the SMA tape subjected to torsion, the martensitic transformation appears along the edge of the tape due to elongation of the edge of the tape and grows to the central part. The fatigue life in both the pulsating torsion and the alternating torsion is expressed by the unified relationship of the dissipated work in each cycle. Based on an opening and closing door model and a solar-powered active blind model, the two-way rotary driving actuator with a small and simple mechanism can be developed by using torsion of the SMA-tape. Keywords: Shape memory alloy, Actuator, Two-way, Tape, Torsion, Fatigue Affiliations:
Tobushi H. | - | Aichi Institute of Technology (JP) | Pieczyska E.A. | - | IPPT PAN | Miyamoto K. | - | Churyo Engineering Co. (JP) | Mitsui K. | - | Masupuro Denkoh Corp. (JP) |
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38. |
Takeda K.♦, Matsui R.♦, Tobushi H.♦, Pieczyska E.A., Creep and creep recovery under stress-controlled subloop loading in TiNi shape memory alloy,
ARCHIVES OF MECHANICS, ISSN: 0373-2029, Vol.65, No.5, pp.429-444, 2013Abstract: If a shape memory alloy (SMA) is subjected to the subloop loading under the stress-controlled condition, creep and creep recovery can appear based on the martensitic transformation. In the design of SMA elements, these deformation properties are important since the deflection of SMA elements can change under constant load. The conditions for the progress of the martensitic transformation are discussed based on the kinetics of the martensitic transformation for the SMA. The creep deformation properties are investigated experimentally for TiNi SMA. The creep strain rate increases in proportion to the martensitic transformation strain; the creep recovery strain rate increases in proportion to the reverse transformation strain. Keywords: shape memory alloy, superelasticity, subloop, transformation band, creep, creep recovery, strain rate, local deformation Affiliations:
Takeda K. | - | Aichi Institute of Technology (JP) | Matsui R. | - | Aichi Institute of Technology (JP) | Tobushi H. | - | Aichi Institute of Technology (JP) | Pieczyska E.A. | - | IPPT PAN |
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39. |
Staszczak M., Pieczyska E.A., Maj M., Urbański L., Tobushi H.♦, Hayashi S.♦, Właściwości mechaniczne oraz zmiany temperatury polimeru z pamięcią kształtu w procesie rozciągania,
POMIARY AUTOMATYKA KONTROLA, ISSN: 0032-4140, Vol.59, No.9, pp.1002-1005, 2013Abstract: This paper presents experimental evaluation of a new polyurethane shape memory polymer (PU-SMP) produced by SMP Technologies Inc. It discusses mechanical characteristics and temperature changes of the SMP specimens subjected to tension test performed at room temperature with various strain rates. Basing on the mechanical data and the relevant temperature changes, we have studied the thermomechanical properties of the PU-SMP and influence of the strain rate on the strain localization behavior. Finally, we have identified the material parameters for the one-dimensional rheological model of the SMP. Keywords: shape memory polyurethane, tension test, dynamic mechanical analysis, infrared camera, temperature change, thermomechanical properties, rheological model Affiliations:
Staszczak M. | - | IPPT PAN | Pieczyska E.A. | - | IPPT PAN | Maj M. | - | IPPT PAN | Urbański L. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) | Hayashi S. | - | SMP Technologies Inc. (JP) |
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40. |
Pieczyska E.A., Tobushi H.♦, Kulasiński K., Takeda K.♦, Impact of Strain Rate on Thermomechanical Coupling Effects in TiNi SMA Subjected to Compression,
MATERIALS TRANSACTIONS, ISSN: 1345-9678, DOI: 10.2320/matertrans.M2012212, Vol.53, No.11, pp.1905-1909, 2012Abstract: In this study, the thermomechanical coupling effects accompanying stress-induced martensitic transformation in TiNi shape memory alloy subjected to compression test were investigated. The mechanical characteristics were elaborated and the temperature changes related to the exothermic martensitic forward transformation and the endothermic reverse one were measured in a contactless manner by a fast and sensitive infrared camera. The obtained temperature changes of the specimen depend on the strain rate applied. At higher strain rate, greater temperature changes were observed, because the heat flow to the surroundings was lower and the process was closer to adiabatic conditions. The temperature changes of the shape memory alloy significantly influence its stressstrain characteristics. Moreover, the energy dissipated during a compression cycle was calculated for various strain rates. The study revealed that both the loading work and recoverable strain energy increase with increasing strain rate, while the dissipated energy fraction decreases.
Keywords: shape memory alloy, compression test, exothermic/endothermic transformation, infrared camera, energy dissipation Affiliations:
Pieczyska E.A. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) | Kulasiński K. | - | IPPT PAN | Takeda K. | - | Aichi Institute of Technology (JP) |
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41. |
Takeda K.♦, Tobushi H.♦, Miyamoto K.♦, Pieczyska E.A., Superelastic Deformation of TiNi Shape Memory Alloy Subjected to Various Subloop Loadings,
MATERIALS TRANSACTIONS, ISSN: 1345-9678, DOI: 10.2320/matertrans.M2011288, Vol.53, No.1, pp.217-223, 2012Abstract: This paper investigates the superelastic deformation behaviors of a TiNi shape-memory alloy (SMA) tape subjected to various subloop loadings in relation to local temperature variations and observed surface changes during a tension test. The results obtained are: (1) Upper and lower stress plateaus appear during loading and unloading accompanying the spreading and shrinking of the stress-induced martensitic transformation (SIMT) bands. In the case of unloading from the upper stress plateau under low stress rate, strain increases due to the spreading of the SIMT bands at the start of the unloading. (2) If stress at the upper stress plateau is held constant, creep deformation appears with the spread of the SIMT bands. The volume fraction in the martensitic phase increases in proportion to the increase in strain. (3) Where the strain is made to vary at the stress plateaus during loading or unloading, a return point memory effect can be seen in the reloading stress-strain curve. The spreading or shrinking of the SIMT bands starts from the boundary of the previous SIMT bands remaining from the preceding process. (4) The inclination angle of the SIMT band boundaries to the tensile axis of the tape is 33° for an aspect ratio of 5. The inclination angle is 42° in the center of the tape and 37° in the vicinity of the end secured by the grip, for an aspect ratio of 10.
Keywords: shape memory alloy, superelasticity, titanium-nickel alloy, subloop, transformation band, creep deformation, local deformation Affiliations:
Takeda K. | - | Aichi Institute of Technology (JP) | Tobushi H. | - | Aichi Institute of Technology (JP) | Miyamoto K. | - | Churyo Engineering Co. (JP) | Pieczyska E.A. | - | IPPT PAN |
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42. |
Pieczyska E.A., Tobushi H.♦, Takeda K.♦, Stróż D.♦, Ranachowski Z., Kulasiński K., Kúdela Jr S.♦, Luckner J., Martensite transformation bands studied in TiNi shape memory alloy by infrared and acoustic emission techniques,
KOVOVE MATERIALY-METALLIC MATERIALS, ISSN: 0023-432X, Vol.50, pp.309-318, 2012Abstract: TiNi shape memory alloy (SMA) specimens have been subjected to tension carried out at various strain rates. The goal was to investigate a nucleation and development of the stressinduced martensitic transformation by infrared (IR) and acoustic emission (AE) techniques. Therefore, both the infrared radiation and acoustic emission data were recorded using a fast infrared camera and acoustic emission set-up, respectively. It has been shown that the initial, macroscopically homogeneous transformation initiates in the elastic stage of the deformation even before the stress-strain curve knee and formation of the localized transformation bands. It has also been found that the homogeneous transformation occurs at similar stress level for all strain rates applied, while the localized martensitic transformation depends on the strain rate. Nucleation and development of the localized transformation bands, detected by the infrared camera, were confirmed by acoustic emission technique. The differences between the IR and AE activities were recorded during the TiNi SMA loading and unloading process, manifesting different dynamics of the stress-induced martensitic forward and reverse transformation. Keywords: shape memory alloy, TiNi, superelasticity, martensitic transformation, tension test, acoustic emission Affiliations:
Pieczyska E.A. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) | Takeda K. | - | Aichi Institute of Technology (JP) | Stróż D. | - | other affiliation | Ranachowski Z. | - | IPPT PAN | Kulasiński K. | - | IPPT PAN | Kúdela Jr S. | - | Institute of Materials and Machine Mechanics, Slovak Academy of Sciences (SK) | Luckner J. | - | IPPT PAN |
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43. |
Takeda K.♦, Tobushi H.♦, Pieczyska E.A., Transformation-Induced Creep and Creep Recovery of Shape Memory Alloy,
Materials, Vol.5, pp.909-921, 2012 | |
44. |
Tobushi H.♦, Hayashi S.♦, Pieczyska E.A., Date K.♦, Nishimura Y.♦, Three-way actuation of shape memory composite,
ARCHIVES OF MECHANICS, ISSN: 0373-2029, Vol.63, No.5-6, pp.443-457, 2011 | |
45. |
Pieczyska E.A., Dutkiewicz J.♦, Masdeu F.♦, Luckner J., Maciak R.♦, Investigation of thermomechanical properties of ferromagnetic NiFeGa shape memory alloy subjected to pseudoelastic compression test,
ARCHIVES OF METALLURGY AND MATERIALS, ISSN: 1733-3490, Vol.56, No.2, pp.401-408, 2011 | |
46. |
Pieczyska E.A., Tobushi H.♦, TiNi shape memory alloy tension at various temperatures - infrared imaging of shape memory effect and pseudoelasticity,
MECHANICS AND CONTROL, ISSN: 2083-6759, Vol.30, No.1, pp.20-26, 2011 | |
47. |
Takeda K.♦, Tobushi H.♦, Miyamoto K.♦, Pieczyska E.A., Subloop Superelastic Deformation of TiNi Shape Memory Alloy,
TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series A , ISSN: 1884-8338, DOI: 10.1299/kikaia.77.1509, Vol.77, No.781, pp.1509-1517, 2011Abstract: The various subloop behaviors for the superelastic deformation of TiNi shape memory alloy were investigated based on the local temperature variation and the surface observation in the tension test. The results obtained are summarized as bellows. (1) The upper and lower stress plateaus during loading and unloading appear accompanying the progress and reduction of the martensitic transformation (MT) band, respectively. In the case of unloading from the upper stress plateau under low stress rate, strain increases due to the progress of the MT band in the initial stage of unloading. (2) If stress is held constant in the upper stress plateau, creep deformation appears. The creep deformation appears based on the progress of the MT band. The volume fraction of the martensitic phase increases in proportion to an increase in strain. (3) If the transformation strain varies in the stress plateau during loading and unloading, the return point memory appears in the reloading stress-strain curve. The progress and reduction of the MT band start from the boundary of the MT band which has appeared in the preceding process. (4) The angle of boundary of the MT band inclined to the tensile axis is 33° for an aspect ratio of 5 and 42° in the central part of the specimen and 37° in the vicinity of the gripping part for an aspect ratio of 10. Keywords: Shape Memory Alloy, Superelasticity, Titanium-Nickel Alloy, Subloop, Transformation Band, Creep Deformation Affiliations:
Takeda K. | - | Aichi Institute of Technology (JP) | Tobushi H. | - | Aichi Institute of Technology (JP) | Miyamoto K. | - | Churyo Engineering Co. (JP) | Pieczyska E.A. | - | IPPT PAN |
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48. |
Tobushi H.♦, Hayashi S.♦, Pieczyska E.A., Date K.♦, Nishimura Y.♦, Three-Way Shape Memory Composite Actuator,
MATERIALS SCIENCE FORUM, ISSN: 0255-5476, Vol.674, pp.225-230, 2011 | |
49. |
Tobushi H.♦, Pieczyska E.A., Miyamoto K.♦, Mitsui K.♦, Shape-Memory Alloy Thin Strip Rotary Actuator,
MATERIALS SCIENCE FORUM, ISSN: 0255-5476, Vol.674, pp.219-224, 2011 | |
50. |
Pieczyska E.A., Activity of stress-induced martensite transformation in TiNi shape memory alloy studied by infrared technique,
JOURNAL OF MODERN OPTICS, ISSN: 0950-0340, Vol.57, No.18, pp.1700-1707, 2010 | |
51. |
Pieczyska E.A., Tobushi H.♦, Date K.♦, Miyamoto K.♦, Torsional deformation and fatigue properties of TiNi SMA thin strip for rotary driving element,
JSME INTERNATIONAL JOURNAL SERIES A-SOLID MECHANICS AND MATERIAL ENGINEERING, ISSN: 1344-7912, Vol.4, No.8, pp.1306-1314, 2010 | |
52. |
Tobushi H.♦, Pieczyska E.A., Nowacki W.K., Date K.♦, Miyamoto K.♦, Two-way rotary shape memory alloy thin strip actuator,
JOURNAL OF THEORETICAL AND APPLIED MECHANICS, ISSN: 1429-2955, Vol.48, No.4, pp.1043-1056, 2010Abstract: In order to develop a two-way rotary shape memory alloy thin strip actuator, the torsional deformation and fatigue properties of a TiNi SMA thin strip were investigated. The results obtained are summarized as follows. (1) In the SMA thin strip subjected to torsion, the MT appears along the edge of the strip due to elongation of the edge of the strip and grows to the central part. (2) The number of cycles to failure decreases with an increase in the maximum angle of twist in torsion fatigue. The fatigue life in pulsating torsion is longer than that in alternating torsion by five times. The fatigue limit exists in a certain value of dissipated work of the strip in each cycle. (3) Based on the two-way motion of a lifting actuator model driven by two kinds of SMA thin strip, it is confirmed that the two-way rotary actuator with a small and simple mechanism can be developed by using the SMA thin strips. Keywords: shape memory alloy, thin strip, torsion, cyclic deformation, fatigue, rotary actuator, two-way motion Affiliations:
Tobushi H. | - | Aichi Institute of Technology (JP) | Pieczyska E.A. | - | IPPT PAN | Nowacki W.K. | - | IPPT PAN | Date K. | - | Ochiai Nexus Co. (JP) | Miyamoto K. | - | Churyo Engineering Co. (JP) |
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53. |
Pieczyska E.A., Gadaj S.P., Nowacki W.K., Luckner J., Tobushi H.♦, Martensite and reverse transformation during simple shear of niti shape memory alloy,
STRAIN, ISSN: 0039-2103, Vol.45, pp.93-100, 2009 | |
54. |
Tobushi H.♦, Pieczyska E.A., Ejiri Y.♦, Sakuragi T.♦, Thermomechanical properties of shape-memory alloy and polymer and their composite,
MECHANICS OF ADVANCED MATERIALS AND STRUCTURES, ISSN: 1537-6494, DOI: 10.1080/15376490902746954, Vol.16, pp.236-247, 2009Abstract: The shape memory effect and superelasticity appear in shape memory alloy (SMA). The large amount of strain by more than several hundreds percent can be recovered in shape memory polymer (SMP). The shape recovery and shape fixity can be used in SMP elements. These characteristics of shape memory materials (SMMs) can be applied to intelligent elements in various fields. In order to use these characteristics and design the SMM elements properly, it is important to understand the thermomechanical properties of SMAs and SMPs. The deformation behaviors of SMMs differ depending on the thermomechanical loading conditions. The main factors which affect these properties are strain rate, stress rate, temperature, subloop loading, temperature-controlled condition, strain holding condition and cyclic loading. In the present paper, the thermomechanical properties of TiNi shape memory alloy, polyurethane-shape memory polymer and their composite are discussed. Keywords: shape memory alloy, shape memory polymer, composite, cyclic loading, strain rate, fatigue Affiliations:
Tobushi H. | - | Aichi Institute of Technology (JP) | Pieczyska E.A. | - | IPPT PAN | Ejiri Y. | - | other affiliation | Sakuragi T. | - | Aichi Institute of Technology (JP) |
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55. |
Tobushi H.♦, Pieczyska E.A., Nowacki W.K., Sakuragi T.♦, Sugimoto Y.♦, Torsional deformation and rotary driving characteristics of SMA thin strip,
ARCHIVES OF MECHANICS, ISSN: 0373-2029, Vol.61, No.3-4, pp.241-257, 2009Abstract: The torsional deformation properties of a TiNi shape-memory alloy thin strip were investigated. The results obtained are summarized as follows. (1) The martensitic transformation starts at the edge of the thin strip. (2) The torsional deformation properties change slightly under thermomechanical cycling. (3) The fatigue life in pul- sating torsion is longer than that in alternating torsion. (4) A simple rotary driving element can be developed by using the SMA thin strip.
Keywords: shape memory alloy, thin strip, torsion, cyclic deformation, fatigue, rotary driving element Affiliations:
Tobushi H. | - | Aichi Institute of Technology (JP) | Pieczyska E.A. | - | IPPT PAN | Nowacki W.K. | - | IPPT PAN | Sakuragi T. | - | Aichi Institute of Technology (JP) | Sugimoto Y. | - | Aichi Institute of Technology (JP) |
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56. |
Tobushi H.♦, Pieczyska E.A., Nowacki W.K., Sugimoto Y.♦, SMA thin strip for rotary-driving element,
SOLID STATE PHENOMENA, ISSN: 1012-0394, DOI: 10.4028/www.scientific.net/SSP.154.47, Vol.154, pp.47-52, 2009Abstract: If a shape-memory alloy (SMA) thin strip is applied as an element subjected to torsion, a rotary driving element with a simple mechanism can be developed. The torsion tests were carried out for the SMA thin strip. Torque and recovery torque, both increase in proportion to the angle of twist and temperature. The recoverable strain energy increases in proportion to temperature. The dissipated work decreases slightly with an increase in temperature. A means of opening and closing a door with an element driven by an SMA thin strip is demonstrated. Keywords: Rotary Driving Element, Shape Memory Alloy Actuator, Strain Energy, Thin Strip, Torsion Affiliations:
Tobushi H. | - | Aichi Institute of Technology (JP) | Pieczyska E.A. | - | IPPT PAN | Nowacki W.K. | - | IPPT PAN | Sugimoto Y. | - | Aichi Institute of Technology (JP) |
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57. |
Pieczyska E.A., Termomechaniczne aspekty przemiany fazowej w stopie TiNi z pamięcią kształtu indukowanej naprężeniem,
POMIARY AUTOMATYKA KONTROLA, ISSN: 0032-4140, Vol.55, No.11, pp.958-961, 2009 | |
58. |
Pieczyska E.A., Nowacki W.K., Tobushi H.♦, Hayashi S.♦, Thermomechanical properties of shape memory polymer subjected to tension in various conditions,
Quantitative InfraRed Thermography Journal, ISSN: 1768-6733, Vol.6, No.2, pp.189-205, 2009Abstract: Thermomechanical and functional properties of shape memory polyurethane are presented. A background of the polymer shape memory effects is described. Elastic modulus at various temperatures and the polyurethane parameters important for the practical applications, called shape fixity and shape recovery, are derived. Taking advantages from the high quality testing machine and infrared camera, mechanical characteristics and temperature changes of the shape memory polyurethane specimens subjected to tension test carried out in various conditions are clarified and analyzed. Stress-strain curves and the relevant temperature changes are recorded both in the elastic and the plastic ranges of deformation. A significant value of a thermoelastic effect is observed. Taking into account the obtained experimental data from the polyurethane tension tests performed at room temperature, followed by the heating above its glass transition temperature, the shape memory polyurethane properties are studied. Keywords: shape memory polyurethane, glass transition temperature, tension, mechanical characteristics, infrared camera, temperature change, thermoelastic effect, localization Affiliations:
Pieczyska E.A. | - | IPPT PAN | Nowacki W.K. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) | Hayashi S. | - | SMP Technologies Inc. (JP) |
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59. |
Dutkiewicz J.M.♦, Maziarz W.♦, Czeppe T.♦, Lityńska L.♦, Nowacki W.K., Gadaj S.P., Luckner J., Pieczyska E.A., Powder metallurgy technology of niti shape memory alloy,
JOURNAL DE PHYSIQUE IV, ISSN: 1155-4339, DOI: 10.1140/epjst/e2008-00654-6, Vol.158, pp.59-65, 2008Abstract: Powder metallurgy technology was elaborated for consolidation of shape memory NiTi powders. The shape memory alloy was compacted from the prealloyed powder delivered by Memry SA. The powder shows Ms = 10°C and As = -34°C as results from DSC measurements. The samples were hot pressed in the as delivered spherical particle's state. The hot compaction was performed in a specially constructed vacuum press, at temperature of 680°C and pressure of 400 MPa. The alloy powder was encapsulated in copper capsules prior to hot pressing to avoid oxidation or carbides formation. The alloy after hot vacuum compaction at 680°C (i.e. within the B2 NiTi stability range) has shown similar transformation range as the powder. The porosity of samples compacted in the as delivered state was only 1%. The samples tested in compression up to ε = 0.06 have shown partial superelastic effect due to martensitic reversible transformation which started at the stress above 300 MPa and returned back to ε = 0.015 after unloading. They have shown also a high ultimate compression strength of 1600 MPa. Measurements of the samples temperature changes during the process allowed to detect the temperature increase above 12°C for the strain rate 10-2 s-1 accompanied the exothermic martensite transformation during loading and the temperature decrease related to the reverse endothermic transformation during unloading. Keywords: Powder metallurgy technology, shape memory alloys, DSC measurements, compression test, exothermic martensite transformation, endothermic reverse transformation Affiliations:
Dutkiewicz J.M. | - | Institute of Metallurgy and Materials Science, Polish Academy of Sciences (PL) | Maziarz W. | - | Institute of Metallurgy and Materials Science, Polish Academy of Sciences (PL) | Czeppe T. | - | Institute of Metallurgy and Materials Science, Polish Academy of Sciences (PL) | Lityńska L. | - | other affiliation | Nowacki W.K. | - | IPPT PAN | Gadaj S.P. | - | IPPT PAN | Luckner J. | - | IPPT PAN | Pieczyska E.A. | - | IPPT PAN |
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60. |
Pieczyska E.A., Tobushi H.♦, Nowacki W.K., Gadaj S.P., Sakuragi T.♦, Subloop deformation behavior of TiNi shape memory alloy subjected to stress-controlled loadings,
MATERIALS TRANSACTIONS, ISSN: 1345-9678, Vol.48, No.10, pp.2679-2686, 2007Abstract: The main characteristics which appear in shape memory alloys (SMAs) are the shape memory effect and superelasticity. In applications of SMAs, the thermomechanical properties of SMAs are most important. The return-point memory does not appear under the stress-controlled conditions. Creep and stress relaxation can be induced due to the phase transformation in the subloop loading under the stress-controlled conditions. In order to design the SMA elements properly, it is important to understand the influence of the thermomechanical loading conditions on the nucleation and progress of the phase transformation and the corresponding deformation behaviors. In the present paper, the conditions for the nucleation and progress of the phase transformation are investigated for SMAs subjected to the subloop loadings under the stress-controlled conditions. The uniaxial tension tests for the TiNi SMAs were carried out in the superelastic region under the various thermomechanical loading conditions. The thermomechanical conditions for the progress of the phase transformation are discussed in the subloop loading under the stresscontrolled conditions. Strain increases during unloading and decreases during reloading under the stress-controlled subloop loading. These pseudoviscoelastic behaviors are important for the precise control of SMA elements. Keywords: shape-memory alloy, titanium-nickel alloy, subloop, superelasticity, creep, stress relaxation, neutral loading Affiliations:
Pieczyska E.A. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) | Nowacki W.K. | - | IPPT PAN | Gadaj S.P. | - | IPPT PAN | Sakuragi T. | - | Aichi Institute of Technology (JP) |
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61. |
Pieczyska E.A., Nowacki W.K., Sakuragi T.♦, Tobushi H.♦, Superelastic deformation properties of TiNi shape memory alloy,
KEY ENGINEERING MATERIALS, ISSN: 1662-9795, DOI: 10.4028/www.scientific.net/KEM.340-341.1211, Vol.340-341, pp.1211-1216, 2007Abstract: The characteristics of energy storage and dissipation in TiNi shape memory alloys were investigated experimentally based on the superelastic properties under various thermomechanical loading conditions. The results obtained can be summarized as follows. (1) The recoverable strain energy increases in proportion to the rise in temperature, but the dissipated work per unit volume depends slightly on temperature. In the case of low strain rates, the recoverable strain energy and dissipated work do not depend on both the strain rate and the temperature-controlled condition. (2) In the case of high strain rates, while the recoverable strain energy decreases and the dissipated work increases in proportion to the rise in strain rate under the temperature-controlled condition, the recoverable strain energy increases and the dissipated work decreases under the temperatureuncontrolled condition. Affiliations:
Pieczyska E.A. | - | IPPT PAN | Nowacki W.K. | - | IPPT PAN | Sakuragi T. | - | Aichi Institute of Technology (JP) | Tobushi H. | - | Aichi Institute of Technology (JP) |
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62. |
Pieczyska E.A., Gadaj S.P., Nowacki W.K., Tobushi H.♦, Superelastic deformation behaviors based on phase transformation bands in TiNi shape memory alloy,
MATERIALS TRANSACTIONS, ISSN: 1345-9678, Vol.47, No.3, pp.670-676, 2006Abstract: Properties and characteristics of superelastic deformation behavior based on Lu¨ders-Like phase transformation bands in TiNi shape memory alloy (SMA) are presented. Temperature distributions accompanying the stress-induced phase transformations in the SMA are found using the infrared technique and employed for the investigation into nucleation and further development of the bands of martensitic and reverse transformations. Based on the temperature and the relevant mechanical characteristics it is noticed that just after crossing a certain threshold stress, narrow bands of considerably higher temperature, about 8K, corresponding to the martensitic phase, appear starting from the central part of the specimen and developing towards the both specimen borders. A few such bands parallel to each other occur at higher stresses and move towards the specimen grips, as well as their next generation, developing in almost perpendicular direction. The heterogeneous field of the temperature distribution was observed also during the unloading process, while the reverse transformation occurred, also inhomogeneous and related to the significant temperature decrease. Based on the tests carried out with various strain rates, an influence of the strain rate on the mechanical behavior was presented. Thermomechanical aspects of the martensitic and the reverse transformations were discussed. Keywords: superelastic deformation, shape memory alloy, phase transformation bands, temperature change, infrared camera Affiliations:
Pieczyska E.A. | - | IPPT PAN | Gadaj S.P. | - | IPPT PAN | Nowacki W.K. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) |
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63. |
Pieczyska E.A., Gadaj S.P., Nowacki W.K., Tobushi H.♦, Phase-transformation fronts evolution for strain- and stress- controlled tension tests in TiNi Shape Memory Alloy,
EXPERIMENTAL MECHANICS, ISSN: 0014-4851, Vol.46, pp.531-542, 2006Abstract: Nucleation and development of phase transformation fronts in TiNi shape memory alloy subjected to the stress- and strain-controlled tension tests were investigated. A thermovision camera was applied to register the distribution of infrared radiation emitted by the specimen and to find its temperature variations. During the loading, narrow bands of considerably higher temperature corresponding to the martensitic phase, starting from the central part of the specimen and developing towards the specimen grips, under both approaches, were registered. The inclined bands of heterogeneous temperature distribution were observed also during the unloading process of the SMA, while the reverse transformation accompanied by temperature decrease took place. Thermomechanical aspects of martensitic and reverse transformations for various strain rates were analyzed under both stress- and strain-controlled tests. Keywords: Shape memory alloy, Martensitic transformation, Phase transformation front, Temperature change, Stress-controlled test, Strain-controlled test, Infrared thermography Affiliations:
Pieczyska E.A. | - | IPPT PAN | Gadaj S.P. | - | IPPT PAN | Nowacki W.K. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) |
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64. |
Pieczyska E.A., Pęcherski R.B., Gadaj S.P., Nowacki W.K., Nowak Z., Matyjewski M.♦, Experimental and theoretical investigations of glass fibre reinforced composite subjected to uniaxial compression for a wide spectrum of strain rates,
ARCHIVES OF MECHANICS, ISSN: 0373-2029, Vol.58, No.3, pp.273-291, 2006Abstract: Results of static and dynamic compression tests for two types of glass fibrereinforced polypropylene composites are presented. Stress-strain curves showing the influence of the strain rate on the composite mechanical properties have been obtained. A three-dimensional description of the material behavior during the deformation has been developed. The material constitutive parameters have been calculated.
Specification of the parameters and description of the methods used for their identification have been worked out. The results are discussed in terms of the deformation processes and the material non-homogeneity. Keywords: static and dynamic compression tests, glass fibrereinforced polypropylene composites, Stress-strain curves, constitutive model, three-dimensional description Affiliations:
Pieczyska E.A. | - | IPPT PAN | Pęcherski R.B. | - | IPPT PAN | Gadaj S.P. | - | IPPT PAN | Nowacki W.K. | - | IPPT PAN | Nowak Z. | - | IPPT PAN | Matyjewski M. | - | other affiliation |
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65. |
Pieczyska E.A., Gadaj S.P., Nowacki W.K., Tobushi H.♦, Stress relaxation during superelastic behavior of TiNi shape memory alloy,
INTERNATIONAL JOURNAL OF APPLIED ELECTROMAGNETICS AND MECHANICS, ISSN: 1383-5416, Vol.23, pp.3-8, 2006 | |
66. |
Pieczyska E.A., Poliuretan z pamięcią kształtu - badania rozciągania oraz prostego ścinania,
PRZEGLĄD MECHANICZNY, ISSN: 0033-2259, Vol.65, pp.38-45, 2006 | |
67. |
Pieczyska E.A., Własności poznawcze i aplikacyjne polimerów stopów z pamięcią kształtu,
NIT. Nauka, Innowacje, Technika, ISSN: 1731-4291, Vol.1, pp.4-10, 2006 | |
68. |
Pieczyska E.A., Gadaj S.P., Nowacki W.K., Hoshito K.♦, Makino Y.♦, Tobushi H.♦, Characteristics of energy storage and dissipation in TiNi shape memory alloy,
SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS, ISSN: 1468-6996, Vol.6, No.8, pp.889-894, 2005Abstract: The characteristics of energy storage and dissipation in TiNi shape memory alloys were investigated experimentally based on the superelastic properties under various thermomechanical loading conditions. The influence of strain rate, cyclic loading and temperature-controlled condition on the characteristics of energy storage and dissipation of the material was investigated. Temperature on the surface of the material was observed and the influence of variation in temperature on the characteristics was clarified. The results obtained can be summarized as follows. (1) In the case of low strain rate, the stress plateaus appear on the stress-strain curves due to the martensitic transformation and the reverse transformation during loading and unloading. In the case of high strain rate, the slopes of the stress–strain curves are steep in the phase-transformation regions during loading and unloading. The recoverable strain energy per unit volume increases in proportion to temperature, but the dissipated work per unit volume depends slightly on temperature. In the case of low strain rate, the recoverable strain energy and dissipated work do not depend on both strain rate and the temperature-controlled condition. (2) In the case of high strain rate, while the recoverable strain energy density decreases and dissipated work density increases in proportion to strain rate under the temperature-controlled condition, the recoverable strain energy density increases and dissipated work density decreases under the temperature-uncontrolled condition. In the case of the temperature-uncontrolled condition, temperature varies significantly due to the martensitic transformation and therefore the characteristics of energy storage and dissipation differ from these under the temperature-controlled condition. (3) In the case of cyclic loading, both the recoverable strain energy and dissipated work decrease in the early 20 cycles, but change slightly thereafter. (4) The influence of strain rate, cyclic loading and the environment on the characteristics of energy storage and dissipation is important to be considered in the design of shape memory alloy elements. q 2005 Elsevier Ltd. All rights reserved. Keywords: Shape memory ally; Superelasticity; Energy storage; Energy dissipation; Damping; Strain rate; Cyclic deformation; Titanium–nickel alloy; Environment Keywords: Shape memory ally, Superelasticity, Energy storage, Energy dissipation, Damping, Strain rate, Cyclic deformation, Titanium–nickel alloy, Environment Affiliations:
Pieczyska E.A. | - | IPPT PAN | Gadaj S.P. | - | IPPT PAN | Nowacki W.K. | - | IPPT PAN | Hoshito K. | - | other affiliation | Makino Y. | - | other affiliation | Tobushi H. | - | Aichi Institute of Technology (JP) |
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69. |
Gadaj S.P., Nowacki W.K., Pieczyska E.A., Tobushi H.♦, Temperature measurement as a new technique applied to the phase transformation study in a TiNi shape memory alloy subjected to tension,
ARCHIVES OF METALLURGY AND MATERIALS, ISSN: 1733-3490, Vol.50, No.3, pp.661-674, 2005 | |
70. |
Gadaj S.P., Nowacki W.K., Pieczyska E.A., Temperature changes of the polymer fibrous belts subjected to mechanical loading,
ENGINEERING TRANSACTIONS (ROZPRAWY INŻYNIERSKIE), ISSN: 0867-888X, Vol.53, No.2, pp.147-163, 2005 | |
71. |
Pieczyska E.A., Gadaj S.P., Nowacki W.K., Tobushi H.♦, Thermomechanical investigations of martensitic and reverse transformations in TiNi shape memory alloy,
BULLETIN OF THE POLISH ACADEMY OF SCIENCES: TECHNICAL SCIENCES, ISSN: 0239-7528, Vol.52, No.3, pp.165-171, 2004Abstract: Shape memory alloys are characterised by interesting properties, i.e. shape memory effect and pseudoelasticity, which enable their
increasing application. Thermomechanical aspects of martensitic and reverse transformations in TiNi shape memory alloy subjected to tension
tests were investigated. The stress-strain characteristics obtained during the tests were completed by the temperature characteristics. The temperature
changes were calculated on the basis of thermograms determined by an infrared camera. Taking advantages from the infrared technique,
the temperature distributions on the specimen’s surface were found. Heterogeneous temperature distributions, related to the nucleation and
development of the new martensite phase, were registered and analysed. A significant temperature increase, up to 30 K, was registered during
the martensitic transformation. The similar effects of the heterogeneous temperature distribution were observed during unloading, while the
reverse transformation, martensite into austenite took place, accompanied by significant temperature decrease. Keywords: shape memory alloy, pseudoelasticity, transformation front, thermomechanical, investigations Affiliations:
Pieczyska E.A. | - | IPPT PAN | Gadaj S.P. | - | IPPT PAN | Nowacki W.K. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) |
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72. |
Pieczyska E.A., Thermoelastic effect in austenitic steel referred to its hardening,
JOURNAL OF THEORETICAL AND APPLIED MECHANICS, ISSN: 1429-2955, Vol.37, No.2, pp.349-367, 1999Abstract: The effects of thermomechanical coupling occurring in metal during consecutive tensile tests, were examined. The temperature, stress and strain characteristic were found both in elastic and plastic ranges. The change of the character of the sample temperature was employed as a criterion for the limit between the elastic and plastic regimes. The thermomechanical coupling effects were interpreted in terms of the material microstructure evolution and referred to its strain hardening degree. A quite precise evaluation of the thermal effects concomitant with the thermoelastic unloading seems to be particularly valuable. Keywords: thermoelastic effect, polycrystaline metal, consecutive deformation Affiliations:
Pieczyska E.A. | - | IPPT PAN |
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73. |
Pieczyska E.A., Wyznaczenie początku odkształcenia plastycznego na podstawie analizy zmian temperatury,
Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.30, pp.1-18, 1995 | |
74. |
Gadaj S.P., Oliferuk W., Pieczyska E.A., Emisja akustyczna podczas deformacji plastycznej stali węglowej,
Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.5, pp.1-15, 1988 | |
75. |
Gadaj S.P., Kaczmarek J., Oliferuk W., Pieczyska E.A., Wpływ obróbki powierzchniowej na proces magazynowania energii podczas rozciągania stali 1H18N9T,
Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.28, pp.1-9, 1983 | |
76. |
Choroś J.♦, Gadaj S.P., Kaczmarek J., Oliferuk W., Pieczyska E.A., Emisja akustyczna towarzysząca przemianom fazowym w deformowanej stali 1H18N9T,
Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.31, pp.1-16, 1982 | |