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Pietrzak K., Gładki A.♦, Strojny-Nędza A.♦, Wejrzanowski T.♦, Kaszyca K.♦, Analysis of uniformity of the distribution of reinforcing phase in Cu/SiC composite materials using mu CT methods,
Image Analysis & Stereology, ISSN: 1580-3139, DOI: 10.5566/ias.1911, Vol.40, No.1, pp.39-47, 2021Streszczenie: Tomography allows embedding of one space in another, especially ℛ2→ℛ3, and observation of the nature of the volumetric internal composite structure. Now, not only a simple interpretation is expected of geometry defined via single thresholds of structures. The binary segmentation used for numerical struc-ture analysis requires more detailed presentation. This paper shows an example of image analysis tech-niques applied to study the homogeneity of two-phase material. Using tomography analysis, the results of the homogeneity of the SiC particles with 10vol.%, 20vol.%, 30vol.%, 40vol.% volumetric bulk density of Cu/SiC composites are presented. Finally, for two independent coordinate systems, the distribution of SiC particle masses and their total moments of inertia were determined. The results confirmed that for well-mixed composite powders the homogeneity of the reinforcing phase is expected in samples with a SiC volume near 30vol.%. In this case, segregation by translation and rotation of SiC particles in the matrix, during the sintering process is restricted. Słowa kluczowe: Cu/SiC composite materials, image analysis, isotropy, uniformity Afiliacje autorów:
Pietrzak K. | - | IPPT PAN | Gładki A. | - | Institute of Electronic Materials Technology (PL) | Strojny-Nędza A. | - | Institute of Electronic Materials Technology (PL) | Wejrzanowski T. | - | Politechnika Warszawska (PL) | Kaszyca K. | - | Lukasiewicz Institute of Microelectronics and Photonics (PL) |
| | 70p. |
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Borkowski P.♦, Pietrzak K.♦, Frydman K.♦, Wójcik-Grzybek D.♦, Gładki A.♦, Sienicki A.♦, Physical and electrical properties of silver-matrix composites reinforced with various forms of refractory phases,
ARCHIVES OF METALLURGY AND MATERIALS, ISSN: 1733-3490, DOI: 10.24425/122408, Vol.68, No.2, pp.817-823, 2018Streszczenie: This paper presents technological trials aimed at producing Ag-W, Ag-WC, Ag-W-C and Ag-WC-C composite contact materials and characterizing their properties. These materials were obtained using two methods, i.e. press-sinter-repress (PSR) at the refractory phase content of less than 30% by weight as well as press-sinter-infiltration (PSI) at the refractory phase content of ≥50% by weight). The results of research into both the physical and electrical properties of the outcome composites were shown. They include the analysis of the influence of the refractory phase content (W or WC) on arc erosion and contact resistance changes for the following current range: 6 kAmax in the case of composites with a low refractory phase content, 10 kAmax in the case of composites with the refractory phase content of ≥50% by weight. Słowa kluczowe: composite materials, electrical contacts, arc erosion, contact resistance Afiliacje autorów:
Borkowski P. | - | Lodz University of Technology (PL) | Pietrzak K. | - | inna afiliacja | Frydman K. | - | Institute of Electronic Materials Technology (PL) | Wójcik-Grzybek D. | - | Institute of Electronic Materials Technology (PL) | Gładki A. | - | Institute of Electronic Materials Technology (PL) | Sienicki A. | - | Lodz University of Technology (PL) |
| | 30p. |
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Strojny-Nędza A.♦, Pietrzak K.♦, Gładki A.♦, Nosewicz S., Jarząbek D.M., Chmielewski M.♦, The effect of ceramic type reinforcement on structure and properties of Cu-Al2O3 composites,
BULLETIN OF THE POLISH ACADEMY OF SCIENCES: TECHNICAL SCIENCES, ISSN: 0239-7528, DOI: 10.24425/124271, Vol.66, No.4, pp.553-560, 2018Streszczenie: The purpose of this paper is to elaborate on mechanical alloying conditions for a composite powder consisting of copper and brittle aluminium oxides. Detailed analysis of the Cu-Al2O3 powder mixture structure obtained in the mechanical alloying process allows for the study of the homogenization phenomena and for obtaining grains (in composite form) with a high degree of uniformity. The Cu-5 vol.%Al2O3 composites were obtained by means of the spark plasma sintering technique. The results presented herein were studied and discussed interms of the impact of using a different form of aluminium oxide powder and a different shape of copper powder on composite properties. Research methodology included microstructure analysis as well as its relation to the strength of Cu-Al2O3 interfaces. It transpires from the results presented below that the application of electrocor undum as a reinforcement phase in composites decreases poro sity in the ceramic phase, thus improving thermal properties and interfacial strength. Słowa kluczowe: metal matrix composites, spark plasma sintering, thermal conductivity, interfacial strength Afiliacje autorów:
Strojny-Nędza A. | - | Institute of Electronic Materials Technology (PL) | Pietrzak K. | - | inna afiliacja | Gładki A. | - | Institute of Electronic Materials Technology (PL) | Nosewicz S. | - | IPPT PAN | Jarząbek D.M. | - | IPPT PAN | Chmielewski M. | - | Institute of Electronic Materials Technology (PL) |
| | 25p. |
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Pietrzak K.♦, Frydman K.♦, Wójcik-Grzybek D.♦, Gładki A.♦, Bańkowska A.♦, Borkowski P.♦, Effect of carbon forms on properties of Ag-C composites contact materials,
MATERIALS SCIENCE, ISSN: 1068-820X, DOI: 10.5755/j01.ms.24.1.17769, Vol.24, No.1, pp.69-74, 2018Streszczenie: This paper presents the manufacturing method of silver based composite materials containing 3 % vol. carbon forms (nanotubes and graphene). The most significant challenge was to obtain good dispersion of carbon in the metallic matrix. The applying of suitable dispersants allows to get uniform distribution of carbon reinforcement. Triton X-100 and ultrasonic support were used in the powder mixing process. Ag-nanotubes and Ag-graphene contact tips were made using Spark Plasma Sintering process (SPS). The results of research into both physical and electrical properties of these composites are presented. It has been demonstrated that the form of introduced carbon exerts influence on the electrical characteristics of contacts, and particularly on arc erosion. Performed electrical test indicated that Ag-nanotubes contacts showed higher resistance to arc erosion than Ag-graphene contacts. It can be explained by the better dispersion to individual carbon nanotubes their lower than for graphene edge defects density and due to this higher thermal and electrical conductivity. Słowa kluczowe: composite materials, silver-nanotubes, silver-graphene, arc erosion, contact resistance Afiliacje autorów:
Pietrzak K. | - | inna afiliacja | Frydman K. | - | Institute of Electronic Materials Technology (PL) | Wójcik-Grzybek D. | - | Institute of Electronic Materials Technology (PL) | Gładki A. | - | Institute of Electronic Materials Technology (PL) | Bańkowska A. | - | Institute of Electronic Materials Technology (PL) | Borkowski P. | - | Lodz University of Technology (PL) |
| | 15p. |
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Pietrzak K.♦, Strojny-Nędza A.♦, Olesińska W.♦, Bańkowska A.♦, Gładki A.♦, Cu-rGO subsurface layer creation on copper substrate and its resistance to oxidation,
APPLIED SURFACE SCIENCE, ISSN: 0169-4332, DOI: 10.1016/j.apsusc.2016.11.155, Vol.421, pp.228-233, 2017Streszczenie: On the basis of a specially designed experiment, this paper presents a model, which is an attempt to explain the mechanism of formatting and creating oxidation resistance of Cu-rGO subsurface layers. Practically zero chemical affinity of copper to carbon is a fundamental difficulty in creating composite structures of Cu-C, properties which are theoretically possible to estimate. In order to bind the thermally reduced graphene oxide with copper surface, the effect of structural rebuilding of the copper oxide, in the process of annealing in a nitrogen atmosphere, have been used. On intentionally oxidized and anoxic copper substrates the dispersed graphene oxide (GO) and thermally reduced graphene oxide (rGO) were loaded. Annealing processes after the binding effects of both graphene oxide forms to Cu substrates were tested. The methods for high-resolution electron microscopy were found subsurface rGO-Cu layer having a substantially greater resistance to oxidation than pure copper. The mechanism for the effective resistance to oxidation of the Cu-rGO has been presented in a hypothetical form Słowa kluczowe: Metal matrix composite, Copper, Graphene, Oxidation Afiliacje autorów:
Pietrzak K. | - | inna afiliacja | Strojny-Nędza A. | - | Institute of Electronic Materials Technology (PL) | Olesińska W. | - | Institute of Electronic Materials Technology (PL) | Bańkowska A. | - | Institute of Electronic Materials Technology (PL) | Gładki A. | - | Institute of Electronic Materials Technology (PL) |
| | 35p. |
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Pietrzak K.♦, Gładki A.♦, Frydman K.♦, Wójcik-Grzybek D.♦, Strojny-Nędza A.♦, Wejrzanowski T.♦, Copper-carbon nanoforms composites – processing, microstructure and thermal properties,
ARCHIVES OF METALLURGY AND MATERIALS, ISSN: 1733-3490, DOI: 10.1515/amm-2017-0198, Vol.62, No.2B, pp.1307-1310, 2017Streszczenie: The main current of publication is focused around the issues and problems associated with the formation of composite materials with Cu matrix and reinforcing phases in the various carbon nanoforms. The core of the research has been focused on thermal conductivity of these composites types. This parameter globally reflects the state of the structure, quality of raw materials and the technology used during the formation of composite materials. Vanishingly low affinity of copper for carbon, multilayered forms of graphene, the existence of critical values of graphene volume in the composite are not conducive to the classic procedures of composites designing. As a result, the expected, significant increase in thermal conductivity of composites is not greater than for pure copper matrix. Present paper especially includes: (i) data of obtaining procedure of copper/graphene mixtures, (ii) data of sintering process, (iii) the results of structure investigations and of thermal properties. Structural analysis revealed the homogenous distribution of graphene in copper matrix, the thermal analysis indicate the existence of carbon phase critical concentration, where improvement of thermal diffusivity to pure copper can occur Słowa kluczowe: metal matrix composite, sintering, copper, graphene, thermal diffusivity Afiliacje autorów:
Pietrzak K. | - | inna afiliacja | Gładki A. | - | Institute of Electronic Materials Technology (PL) | Frydman K. | - | Institute of Electronic Materials Technology (PL) | Wójcik-Grzybek D. | - | Institute of Electronic Materials Technology (PL) | Strojny-Nędza A. | - | Institute of Electronic Materials Technology (PL) | Wejrzanowski T. | - | Politechnika Warszawska (PL) |
| | 30p. |