Formation Mechanism of Lamellar M_(23)C_6 Carbide in a Cobalt-Base Superalloy During Thermal Exposure at 1000℃

作     者：Wei-Min Gui Hong-Yu Zhang Hai-Bo Long Tao Jin Xiao-Feng Sun Qi Zheng 

作者机构：Superalloys Division Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China Beijing Key Laboratory of Microstructure and Property of Advanced Materials Institute of Microstructure and Property of Advanced Materials Beijing University of Technology 

出 版 物：《Acta Metallurgica Sinica(English Letters)》 (金属学报（英文版）)

年 卷 期：2018年第31卷第1期

页      面：27-32页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：supported by the National Natural Science Foundation of China (Nos. 51331005, 51601192, 51671188 and 11332010) the High Technology Research and Development Program of China (No. 2014AA041701) 

主　　题：Cobalt-base superalloy Carbide precipitation Thermal exposure Scanning/transmission electron microscopy 

摘      要：The precipitation of the lamellar-shaped M23C6 carbide within the dendritic matrix of a cobalt-base superalloy during thermal exposure at 1000 ℃ has been investigated. Such a precipitation is not commonly observed in cobalt-base superalloys. It is found that M23C6 particles nucleate preferentially at stacking faults （SFs） in the dendritic matrix and grow along the SFs to develop a lamellar character. Additionally, a Cr depletion zone is observed in the vicinity of the lamellar M23C6 carbide, which strongly supports the presence of Suzuki segregation.