The Effect of Ru on the Evolution of the γ′ Phase in Ni-Al-Ru Alloys

Materials

Shaoyang Wang¹  Lu Wang¹  Hongying Yu¹  Dongbai Sun¹  Fanqiang Meng² 

[1] School of Materials, Sun Yat-sen University, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangzhou 510275, China;Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, China;

关键词: ruthenium;    microstructure evolution;    partitioning behavior;    lattice misfit;   

DOI  :  10.3390/ma15093344

来源: DOAJ

【 摘 要 】

With the development and wide application of nickel-based single-crystal superalloys, the effect of Ru on the microstructure stability and high-temperature properties of superalloys is becoming increasingly important. In this study, the effect of Ru on the evolution of the γ′ phase in Ni-Al-Ru ternary alloys during aging treatment was analyzed, using a scanning electron microscope and transmission electron microscope, combined with energy-dispersive spectroscopy. The relationship between chemical partition behavior and γ/γ′ lattice misfit was investigated in detail. During the aging process, Ru addition suppressed the growth rate and rafting process of γ′ precipitates, while the effect of Ru on hindering γ′ phase growth was reduced when the Ru content was over 3 at%. Ru preferentially partitioned to the γ phase, and its partitioning ratio to the γ phase increased with a variation in Ru content from 1 at% to 3 at% and decreased for the NiAl6Ru alloy. Additionally, the lattice misfit of all alloys was positive and reduced with the increase in Ru content, which hindered the Ru atoms to diffuse into the γ phase and promoted the shape of γ′ precipitates to change from cubic to spherical.

【 授权许可】

Unknown