摘要
采用光学金相显微镜、拉伸试验机、显微硬度仪、扫描电镜等研究了超声辅助对2 mm厚2524铝合金板材搭接搅拌摩擦点焊焊接接头组织与力学性能的影响。结果表明,施加超声后,接头有效连接宽度由1 763μm提升至2 399μm,热机影响区畸变程度降低,焊核区晶粒明显细化,断口韧窝更细小、均匀,第二相粒子分布更均匀、弥散。接头显微硬度从焊核区到母材区呈现先降低后回升的趋势,施加超声后焊核区内显微硬度略有提升,但幅度不大。接头最大剪切拉伸载荷从未施加时的4 246 N增至5 267 N。
The effect of ultrasonic assistance on the microstructure and mechanical properties of a 2 mm-thick lap joint of 2524 aluminum alloy sheet by friction stir spot welding was studied by means of optical metallographic microscope,tensile testing machine,microhardness tester and scanning electron microscope.The results show that after adopting ultrasound assistance,the effective width of the joint increases from 1763μm to 2399μm,the distortion amount of the thermo-mechanically affected zone is reduced,the grain size of particles in the welding nugget zone is obviously finer,the fracture dimples become smaller and are evenly distributed.The second-phase particles are also evenly distributed and dispersed.The microhardness of the joint shows gradual rising trend after an initial fall from the welding nugget zone to the base material.The microhardness in the welding nugget zone just increases slightly after applying ultrasonic assistance.The maximum shear tensile load of the joint is increased from 4246 N before to 5267 N after the ultrasonic assistance.
作者
胡一杰
孙有平
周思鹏
何江美
杨春洋
HU Yi-jie;SUN You-ping;ZHOU Si-peng;HE Jiang-mei;YANG Chun-yang(School of Mechanical and Transportation Engineering,Guangxi University of Science and Technology,Liuzhou 545006,Guangxi,China)
出处
《矿冶工程》
CAS
CSCD
北大核心
2021年第3期129-133,共5页
Mining and Metallurgical Engineering
基金
柳州市科学研究与技术开发计划(2017BD20301)
广西研究生教育创新计划项目(YCSW2020217)。
关键词
焊接接头组织
2524铝合金
搅拌摩擦点焊
显微组织
力学性能
超声辅助
microstructure of welding joint
2524 aluminum alloy
friction stir spot welding
microstructure
mechanical properties
ultrasonic assistance
