Microstructural and nanomechanical behavior of friction stir welded dissimilar joint of AA2219-T6/AA2195-T8 alloys  

作　　者：Di-chao Wu Fei-fan Wang Shen Li Wen-qin Wang De Wang Yu-long Li Tan Miao 

机构地区：[1]School of Advanced Manufacturing,Nanchang University,Nanchang,330031,Jiangxi,China [2]Beijing Institute of Astronautical Systems Engineering,China Academy of Launch Vehicle Technology,Beijing,100076,China [3]School of Aeronautical Manufacturing Engineering,Nanchang Hangkong University,Nanchang,330063,Jiangxi,China

出　　处：《Journal of Iron and Steel Research International》2024年第12期3080-3094,共15页钢铁研究学报(英文版)

基　　金：This work was supported by the National Natural Science Foundation of China(Nos.52375305,52205375,U21B6004).

摘　　要：To achieve the new strategy of low cost and outstanding property,friction stir welding(FSW)was used to join AA2219-T6 alloy and AA2195-T8 alloy.The relationship between macro/microstructure and nanomechanical properties was established by using a nanoindentation instrument.During FSW,the grains in stir zone were refined by recrystallization,and the main mechanism of recrystallization was continuous dynamic recrystallization and geometric dynamic recrystallization.The overall micro-hardness value of AA2195 alloy was higher than that of AA2219 alloy due to the strength of the material,and the decrease in hardness value is attributed to the dissolution and coarsening of precipitation.Each zone of the dissimilar joint showed obvious indentation size effect,and the highest nano-hardness values of 2219-base metal(BM)and 2195-BM zones were 1.42 and 1.71 GPa,respectively.The nano-hardness is closely related to the precipitation behavior and follows the same law as the distribution of micro-hardness.The creep mechanism was mainly dislocation slip.The combined action of grain boundary,dislocation,and coarse precipitation can affect creep resistance,in which coarse precipitation plays a dominant role.

关 键 词：Friction stir welding Aluminum alloy Microstructure NANOINDENTATION CREEP 

分 类 号：TG1[金属学及工艺—金属学]