Microstructure Evolution and Recrystallization Behavior of Friction Stir Welded Thick Al-Mg-Zn-Cu alloys:Influence of Pin Centerline Deviation

作     者：Yu-Qing Mao Ping Yang Li-Ming Ke Yang Xu Yu-Hua Chen Yu-Qing Mao;Ping Yang;Li-Ming Ke;Yang Xu;Yu-Hua Chen

作者机构：National Defence Key Discipline Laboratory of Light Alloy Processing Science and TechnologyNanchang Hangkong UniversityNanchang330063China 

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

年 卷 期：2022年第35卷第5期

页      面：745-756页

核心收录：

学科分类：08[工学] 0817[工学-化学工程与技术] 0806[工学-冶金工程] 0807[工学-动力工程及工程热物理] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0802[工学-机械工程] 0703[理学-化学] 0811[工学-控制科学与工程] 080201[工学-机械制造及其自动化] 

基　　金：financially supported by the National Natural Science Foundation of China(NSFC)(Nos.52164045,52005240,51874179,51865035) the Natural Science Foundation Project of Jiangxi Province of China(No.20202BAB214019) the Key Laboratory Fund Project(No.EG202080409)。 

主　　题：Thick Al-Mg-Zn-Cu alloys Friction stir welding Pin centerline deviation Microstructure evolution Recrystallization behavior 

摘      要：Four tools with different pin centerline deviations were fabricated to friction stir weld(FSW)thick plates of Al-Mg-Zn-Cu alloys.The results show that,compared with the pin without pin centerline deviation,the applying of pin centerline deviation is favorable to improve the flowability of plastic material,enlarging the size of nugget zone,refining the grains and reprecipitated phase particles,enhancing the degrees of dynamic recrystallization and quantity of high angle grain boundaries owing to higher temperature and bigger eccentric force,resulting in the increase of strain hardening.Especially for the used pin with a centerline deviation of 0.2 mm,the highest average hardness and best metallurgical properties of thick FSW joints are produced,and which are consistent with the microstructure evolution and recrystallization behavior.Moreover,the fracture mode of the joints produced by the pins with centerline deviation from 0 mm to 0.3 mm changes gradually from a brittle fracture in the nugget zone(NZ)to a ductile failure in the HAZ.