Coarsening behavior of γ' and γ'' phases in GH4169 superalloy by electric field treatment  

作　　者：Lei Wang Yao Wang Yang Liu Xiu Song Xu-dong Lü Bei-jiang Zhang 

机构地区：[1]Key Laboratory for Anisotropy and Texture of Materials, Northeastern University [2]Department of High-temperature Materials, Central Iron and Steel Research Institute

出　　处：《International Journal of Minerals,Metallurgy and Materials》2013年第9期861-866,共6页矿物冶金与材料学报（英文版）

基　　金：financially fnancially supported by the National Natural Science Foundation of China(No.51171039);the Major State Basic Research Development Program of China(No.2010CB631203);the Fundamental Research Funds for the Central Universities of China(No.N100602002);the 2010 Academy Awards Sponsorship of Doctoral Candidate for Newcomer of China(No.22002096)

摘　　要：The coarsening behaviors of γ′ and γ″ phases in GH4169 alloy aged at 1023 and 1073 K with electric field treatment （EFT） were investigated by transmission electron microscopy （TEM） and positron annihilation lifetime spectroscopy （PALS）. It is demonstrated that precipitation coarsening occurs, and the growth activation energies of γ′ and γ″phases can be decreased to 115.6 and 198.1 kJ.mo1-1, respectively, by applying the electric field. The formation of a large number of vacancies in the matrix is induced by EFT. Due to the occurrence of vacancy migration, the diffusion coefficients of A1 and Nb atoms are increased to be 1.6-5.0 times larger than those without EFT at 1023 or 1073 K. Furthermore, the formation of vacancy clusters is promoted by EFT, and the increase in strain energy for the coarsening of γ′ and γ″ phases can be counterbalanced by the formation of vacancy clusters.The coarsening behaviors of γ′ and γ″ phases in GH4169 alloy aged at 1023 and 1073 K with electric field treatment （EFT） were investigated by transmission electron microscopy （TEM） and positron annihilation lifetime spectroscopy （PALS）. It is demonstrated that precipitation coarsening occurs, and the growth activation energies of γ′ and γ″phases can be decreased to 115.6 and 198.1 kJ.mo1-1, respectively, by applying the electric field. The formation of a large number of vacancies in the matrix is induced by EFT. Due to the occurrence of vacancy migration, the diffusion coefficients of A1 and Nb atoms are increased to be 1.6-5.0 times larger than those without EFT at 1023 or 1073 K. Furthermore, the formation of vacancy clusters is promoted by EFT, and the increase in strain energy for the coarsening of γ′ and γ″ phases can be counterbalanced by the formation of vacancy clusters.

关 键 词：SUPERALLOYS nickel alloys PRECIPITATION electric fields AGING VACANCIES 

分 类 号：TG132.32[一般工业技术—材料科学与工程]