Microstructure Evolution during Laser Cladding of Nickel Aluminide/Chromium Carbide Coatings
Nickel aluminide based intermetallic materials can be used in specific applications requiring high temperature strength and oxidation resistance.In this study,Fe-rich nickel aluminide based intermetallic alloy(NAC-alloy)was designation and its pre-alloyed powder incorporating all alloying elements as well as mixes of nickel aluminide powder with Cr3C2 powder were used.In general,if hard phases such as chromium carbide is incorporated,the wear resistance of the material can be significantly improved.Particularly,the robustness of the formed microstructure is addressed.The tested samples with adjusted laser cladding parameters just outside the “normal process window was used to assess the robustness of the microstructure.X-ray diffraction,Scanning electron microscopy(SEM)plus Energy dispersive spectroscopy(EDS)and Electron back scattering diffraction(EBSD)were applied to characterization the microstructure of the coatings.In this study,the area fraction of the phases found was estimated and its morphology was studied by correlation its laser cladding parameters.The area fraction of Cr-carbides(Cr3C2/M7C3)is estimated around 25 wt.%in the both of powders which is also coherence with these powder materials designed.The preliminary results show that M7C3 is mostly formed by precipitation from the(NiFeCr)3Al matrix during laser cladding process.Vickers hardness HV(300 g)on the coating and its substrate has a widely range of 620 to 230 which it is from the top of coating material to the bottom of its substrate.
Nickel aluminide Chromium carbide Laser cladding and Electron back scattering diffraction
Gong Karin Bengtsson Sven Zhao Lin Tian Zhiling
Chalmers University of Technology,Gothenburg,Sweden H(o)gan(a)s AB,H(o)gan(a)s,Sweden China Iron & Steel Research Institute Group(CISRI),Beijing,China
国际会议
北京
英文
123-135
2018-09-16（万方平台首次上网日期，不代表论文的发表时间）