Microstructures and mechanical properties of friction stir welds on 9% Cr reduced activation ferritic/martensitic steel

作     者：Chao Zhang Lei Cui Yongchang Liu Chenxi Liu Huijun Li 

作者机构：State Key Lab of Hydraulic Engineering Simulation and SafetySchool of Materials Science & EngineeringTianjin University Tianjin Key Laboratory of Advanced Joining TechnologySchool of Materials Science and EngineeringTianjin University 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2018年第34卷第5期

页      面：756-766页

核心收录：

学科分类：080503[工学-材料加工工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0802[工学-机械工程] 080201[工学-机械制造及其自动化] 

基　　金：financially supported by the National Natural Science Foundation of China (Grant Nos.51325401 and U1660201) the National Magnetic Confinement Fusion Energy Research Project (Grant No.2015GB119001) 

主　　题：Friction stir welding Reduced activation ferritic/martensitic steel Microstructure evolution Impact toughness 

摘      要：In this study,the microstructures and mechanical properties of 9%Cr reduced activation ferritic/martensitic（RAFM） steel friction stir welded joints were *** a W-Re tool is used,the recommended welding parameters are 300 rpm rotational speed,60 mm/min welding speed and10 kn axial *** stir zone（SZ）,austenite dynamic recrystallization induced by plastic deformation and the high cooling rates lead to an obvious refinement of prior austenite grains and martensite *** microstructure in SZ contains lath martensite with high dislocation density,a lot of nano-sized MX and M3C phase particles,but almost no M23C6 *** thermal mechanically affect zone（TMAZ）and heat affect zone（HAZ）,refinement of prior austenite and martensitic laths and partial dissolution of M（23）C6 precipitates are obtained at relatively low rotational ***,with the increase of heat input,coarsening of martensitic laths,prior austenite grains,and complete dissolution of M23C6 precipitates are *** toughness of SZ at-20℃ is slightly lower than that of base material（BM）,and exhibits a decreasing trend with the increase of rotational speed.