Suppressing the formation of SRZ in a Ni-based single crystal superalloy by RuNiAl diffusion barrier  

作　　者：Zhiming Bai Dongqing Li Hui Peng Juan Wang Hongbo Guo Shengkai Gong 

机构地区：[1]School of Materials Science and Engineering, Beihang University, No. 37, Xueyuan Road, Beijing 100191, China

出　　处：《Progress in Natural Science:Materials International》2012年第2期146-152,共7页自然科学进展·国际材料（英文版）

基　　金：sponsored by National Nature Science Foundations of China(NSFC nos.50731001 and 51071013);National Basic Research Program(973 Program) of China under Grant no.2010CB631200

摘　　要：NiAl-based bond coats applied in thermal barrier coating(TBC)systems containing Ru and Pt have been studied in recent years.Interdiffusion between the coatings and the underlying superalloy substrates usually results in degradation of the mechanical properties of the substrates.In this paper,a NiAl/Ru coating was deposited onto a single crystal superalloy DD6 by electroplating and electron beam physical vapor deposition(EB-PVD).Interdiffusion behavior of the NiAl/Ru and NiAl coated specimens at 1100 1C was comparatively investigated.For the NiAl coated specimen,after 100 h vacuum annealing,beneath the coating there was a 50 mm thickness secondary reaction zone(SRZ)with some needle-like topologically closed packed(TCP) phases.However no SRZ was observed in the NiAl/Ru coated specimen.This may be attributed to the RuNiAl that acted as a diffusion barrier to prevent the inward diffusion of Al from the coating and the outward diffusion of refractory elements from the substrate,and hence suppressing the formation of TCP phases and SRZ in the superalloy.NiAl-based bond coats applied in thermal barrier coating (TBC) systems containing Ru and Pt have been studied in recent years. Interdiffusion between the coatings and the underlying superalloy substrates usually results in degradation of the mechanical properties of the substrates. In this paper, a NiAl/Ru coating was deposited onto a single crystal superalloy DD6 by electroplating and electron beam physical vapor deposition (EB-PVD). Interdiffusion behavior of the NiAl/Ru and NiAl coated specimens at 1100 °C was comparatively investigated. For the NiAl coated specimen, after 100 h vacuum annealing, beneath the coating there was a 50 μm thickness secondary reaction zone (SRZ) with some needle-like topologically closed packed (TCP) phases. However no SRZ was observed in the NiAl/Ru coated specimen. This may be attributed to the RuNiAl that acted as a diffusion barrier to prevent the inward diffusion of Al from the coating and the outward diffusion of refractory elements from the substrate, and hence suppressing the formation of TCP phases and SRZ in the superalloy.

关 键 词：NIAL RuNiAl COATING INTERDIFFUSION SECONDARY REACTION zone(SRZ) 

分 类 号：TG132.32[一般工业技术—材料科学与工程]