1. |
Pietrzak K., Strojny-Nędza A.♦, Kaszyca K.♦, Shepa I.♦, Mudra E.♦, Vojtko M.♦, Dusza J.♦, Antal V.♦, Hovancova J.♦, Chmielewski M.♦, Oxidation and corrosion resistance of NiCr-Re and NiCr-Re-Al2O3 materials fabricated by spark plasma sintering,
Metals, ISSN: 2075-4701, DOI: 10.3390/met10081009, Vol.10, No.8, pp.1009-1-12, 2020Streszczenie: The thermal and oxidation resistance of elements found in the combustion boilers of power generation plants are some of the most important factors deciding their effectiveness. This paper shows the experimental results of the influence of NiCr-based material composition on the microstructure and phase changes occurring during the oxidation and corrosion process. NiCr alloy was modified by the addition of rhenium and aluminum oxide. Materials were densified using the spark plasma sintering method at a sintering temperature of 1050 °C. Oxidation tests conducted up to 1100 °C under synthetic airflow revealed the formation of a thin Cr2O3 layer protecting the material against in-depth oxidation. Results of electrochemical corrosion in a 0.5 M NaCl solution indicated a positive role of Re and Al2O3 addition, confirmed by low corrosion current density values in comparison to the other reference materials. According to the provided positive preliminary test results, we can conclude that a NiCr-Re-Al2O3 system in coating form was successfully obtained by the plasma spraying method. Słowa kluczowe: NiCr, rhenium, aluminium oxide, metal matrix composites, oxidation, corrosion Afiliacje autorów:
Pietrzak K. | - | IPPT PAN | Strojny-Nędza A. | - | Institute of Electronic Materials Technology (PL) | Kaszyca K. | - | Lukasiewicz Institute of Microelectronics and Photonics (PL) | Shepa I. | - | inna afiliacja | Mudra E. | - | inna afiliacja | Vojtko M. | - | inna afiliacja | Dusza J. | - | Institute of Materials Research, Slovak Academy of Sciences (SK) | Antal V. | - | inna afiliacja | Hovancova J. | - | inna afiliacja | Chmielewski M. | - | Institute of Electronic Materials Technology (PL) |
| | 70p. |
2. |
Medved D.♦, Ivor M.♦, Chmielewski T.♦, Golański D.♦, Pietrzak K.♦, Kottfer D.♦, Dusza J.♦, Microstructure characteristics, tribology and nano-hardness of plasma sprayed NiCrRe coating,
DEFECT AND DIFFUSION FORUM, ISSN: 1662-9507, DOI: 10.4028/www.scientific.net/DDF.405.430, Vol.405, pp.430-434, 2020Streszczenie: This paper presents the results of the investigation of NiCrRe coating deposited by plasma spray process at the atmospheric pressure on boiler steel substrate. These coatings were characterized by means of a scanning electron microscopy, and Energy-dispersive X-ray spectroscopy. The wear resistance of plasma sprayed NiCrRe coatings has been investigated under dry sliding conditions at applied load of 10 N in air. The continuous stiffness measurement (CSM) method was used for the investigation of nanohardness using Agilent G200 Nano-indenter in order to determine the mechanical properties of the coatings. Microstructural observations pointed out that the NiCr layer with white isles of rhenium possessed porosity, oxidized, un-melted and semimelted particles, and inclusions. According to the results the thickness of the layer is 450 μm, the indentation modulus 158 ± 24.4 GPa, hardness 3.74 ± 0.76 GPa and the coefficient of friction is 0.45. Słowa kluczowe: coating, plasma, tribology Afiliacje autorów:
Medved D. | - | inna afiliacja | Ivor M. | - | inna afiliacja | Chmielewski T. | - | Politechnika Warszawska (PL) | Golański D. | - | Politechnika Warszawska (PL) | Pietrzak K. | - | inna afiliacja | Kottfer D. | - | inna afiliacja | Dusza J. | - | Institute of Materials Research, Slovak Academy of Sciences (SK) |
| |
3. |
Ivor M.♦, Medved D.♦, Chmielewski T.♦, Tobota K.♦, Pietrzak K.♦, Chmielewski M.♦, Halama M.♦, Kottfer D.♦, Dusza J.♦, Microstructure characteristics, tribology and nano-hardness of HVOF sprayed NiCrRe coating,
DEFECT AND DIFFUSION FORUM, ISSN: 1662-9507, DOI: 10.4028/www.scientific.net/DDF.405.435, Vol.405, pp.435-439, 2020Streszczenie: The high-velocity oxy-fuel technique (HVOF) was used to produce dense NiCrRe coating on boiler steel substrate with a minimal amount of oxide impurities and low porosity. Microstructure analysis, tribology and nano-hardness measurement have been realized with the aim to characterize the systems. The microstructure was studied using scanning electron microscopy and Energy-dispersive X-ray spectroscopy. Tribological characteristics have been studied under the dry sliding condition at applied loads of 5, 10 and 20 N using the ball-on-flat technique with SiC ball at room temperature. Nano-hardness was investigated in continuous stiffness measurement (CSM) mode, the indentation depth limit was 1500 nm. Microstructure analyses proved that the HVOF sprayed layer, with a thickness approximately 870 µm, contains a relatively low volume fraction of porosity with a chemical composition based on Nickel, Chromium, with white areas of Rhenium. The wear rate of the coating is significantly lower than the wear rate of 16Mo3 steel. The average values of indentation modulus and hardness were EIT = 237.6 GPa and HIT = 6.3 GPa, respectively. Słowa kluczowe: HVOF, mechanical properties of NiCrRe, NiCrRe coating Afiliacje autorów:
Ivor M. | - | inna afiliacja | Medved D. | - | inna afiliacja | Chmielewski T. | - | Politechnika Warszawska (PL) | Tobota K. | - | inna afiliacja | Pietrzak K. | - | inna afiliacja | Chmielewski M. | - | Institute of Electronic Materials Technology (PL) | Halama M. | - | inna afiliacja | Kottfer D. | - | inna afiliacja | Dusza J. | - | Institute of Materials Research, Slovak Academy of Sciences (SK) |
| |