2024铝合金搅拌摩擦焊过程组织演化分析  

Microstructure evolution during friction stir welding of 2024 aluminum alloy

作　　者：张成聪[1] 常保华[1] 陶军[2] 张田仓[2] 

机构地区：[1]清华大学先进成形制造教育部重点实验室,北京100084 [2]北京航空制造工程研究所航空发动机工艺研究室,北京100024

出　　处：《焊接学报》2013年第3期57-60,116,共4页Transactions of The China Welding Institution

基　　金：航空重点基金资助项目(2009ZE25007)

摘　　要：采用"急停快冷"的方法对2024铝合金搅拌摩擦焊(FSW)的组织演化过程进行了研究,对搅拌头前、后方不同区域进行了EBSD测试,分析了FSW过程中组织演化的规律和机理.结果表明,在FSW前期发生了不连续动态再结晶,在FSW过程中与亚晶界吸收位错而取向差增加相关的连续动态再结晶是其动态形核的主导机制,在随后的冷却过程中晶粒长大成为终态组织,期间发生了部分的静态再结晶.The 'abrupt stop and rapid cooling' technique was used to study the microstructure evolution during friction stir welding(FSW) of 2024 aluminum alloy.Electron backscattered diffraction(EBSD) maps were taken in different regions behind and ahead of the tool keyhole,and the characteristics and mechanism of microstructure evolution were analyzed.The results show that discontinuous recrystallization occurred in early stage of FSW.The continuous recrystallization,resulted from the gradual increase of subgrain boundary misorientation due to absorption of dislocation,was the dominating mechanism of dynamic nucleation during FSW.Grains grew to the final structures during the subsequent cooling cycle,in which partial static recrystallization occurred.

关 键 词：搅拌摩擦焊 动态再结晶 组织演化 电子背散射衍射 

分 类 号：TG453[金属学及工艺—焊接]