High-temperature creep rupture behavior of dissimilar welded joints of RAFM steel and 316L steel by friction stir welding  

作　　者：Xin Ji Bin He Wei Guan Chen-xi Liu Hui-jun Li Lei Cui Yong-chang Liu 

机构地区：[1]Tianjin Key Laboratory of Advanced Joining Technology,School of Materials Science and Engineering,Tianjin University,Tianjin,300354,China [2]State Key Lab of Hydraulic Engineering Simulation and Safety,School of Materials Science and Engineering,Tianjin University,Tianjin,300350,China

出　　处：《Journal of Iron and Steel Research International》2024年第10期2438-2447,共10页钢铁研究学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(52034004).

摘　　要：Creep rupture of the reduced activation ferritic/martensitic(RAFM)steel and 316L steel dissimilar joint by friction stir welding was investigated.The creep rupture time of the dissimilar joint was 1941 h at 600℃/100 MPa and 120 h at 650℃/100 MPa.The creep fracture occurred in heat affect zone(HAZ)of RAFM steel side where coarse Laves phase was detected.The formation and coarsening of the Laves phase particles in HAZ of RAFM steel side were the main reasons that caused the creep fracture of the dissimilar joint.The Laves phase particles nucleated adjacent to the large M_(23)C_(6) particles at the grain boundaries where W element segregated and grew fast during creep exposure.The large Laves phase would deteriorate the pinning effect of M_(23)C_(6) carbides and weaken the solid solution strengthening effect.Besides,the size of the Laves phase in HAZ of RAFM steel side was bigger than that in stir zone of RAFM steel side.These reasons explain the creep fracture in HAZ of RAFM steel side of dissimilar joint.

关 键 词：Creep behavior Dissimilar joint Friction stir welding Laves phase M23C6 carbide 

分 类 号：TG453.9[金属学及工艺—焊接]