Interdiffusion behavior of Pt-modified γ-Ni+γ′-Ni₃Al alloys coupled to Ni-Al-based alloys

作     者：Hayashi, S Wang, W Sordelet, DJ Gleeson, B 

作者机构：the Research Group of Interface Control Engineering Graduate School of Engineering Hokkaido University 060-8628 Sapporo Japan the State Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences 110016 Shenyang P.R. China Present address: the Department of Materials Science and Engineering Iowa State University 50011 Arnes IA 

出 版 物：《METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE》 (冶金学与材料汇刊A辑：物理冶金学与材料科学)

年 卷 期：2005年第36A卷第7期

页      面：1769-1775页

核心收录：

学科分类：0806[工学-冶金工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

摘      要：The effect of platinum addition on the interdiffusion behavior of gamma-Ni + gamma -Ni3Al alloys was studied by using diffusion couples comprised of a Ni-Al-Pt alloy mated to a Ni-Al, Ni-Al-Cr, or Ni-based commercial alloy. The commercial alloys studied were CMSX-4 and CMSX-10. Diffusion annealing was at 1150 degrees C for up to 100 hours. An Al-enriched gamma -layer often formed in the interdiffusion zone of a given couple during diffusion annealing due to the uphill diffusion of Al. This uphill diffusion was ascribed to Pt addition decreasing the chemical activity of aluminum in the gamma + gamma , alloys. For a given diffusion couple end member, the thickening kinetics of the gamma layer that formed increased with increasing Pt content in the Ni-Al-Pt gamma + gamma alloy. The gamma -layer thickening kinetics in diffusion couples with Cr showed less of a dependence on Pt concentration. Inference of a negative effect of Pt and positive effect of Cr on the Al diffusion in this system enabled explanation of the observed interdiffusion behaviors. There was no or minimal formation of detrimental topologically close-packed (TCP) phases in the interdiffusion zone of the couples with CMSX-4 or CMSX- 10. An overlay Pt-modified gamma + gamma coating on CMSX-4 showed excellent oxidation resistance when exposed to air for 1000 hours at 1150 degrees C. Moreover, the Al content in the coating was maintained at a relatively high level due to Al replenishment from the CMSX-4 substrate.