超声冲击调控2219铝合金搅拌摩擦焊接头残余应力  

Adjusting Residual Stress of Friction Stir Welding for 2219 Aluminum Alloy by Ultrasonic Impact Treatment

作　　者：赵耀邦[1] 雷亚彤 程立宏 别亚星 历吴恺 徐爱杰[1] 王建峰 ZHAO Yaobang;LEI Yatong;CHENG Lihong;BIE Yaxing;LI Wukai;XU Aijie;WANG Jianfeng(Shanghai Spaceflight Precision Machinery Institute,Shanghai 201600,China;Shanghai Aerospace System Engineering Institute,Shanghai 201600,China;College of Material Science and Technology,Nanjing University of Aeronautics and Astronautics,Nanjing 211106,Jiangsu,China)

机构地区：[1]上海航天精密机械研究所,上海201600 [2]上海宇航系统工程研究所,上海201600 [3]南京航空航天大学材料科学与工程学院,江苏南京211106

出　　处：《上海航天(中英文)》2024年第S2期65-70,共6页Aerospace Shanghai(Chinese&English)

基　　金：基础科研计划项目(JCKY2023605C010)

摘　　要：针对铝合金贮箱搅拌摩擦焊接低残余应力的设计需求,提出了利用超声冲击处理产生的残余压应力调控焊接应力,发现了低残余应力制造、高可靠服役寿命的方法。在2219铝合金搅拌摩擦焊接头上开展不同激励电流的超声冲击试验,通过X射线衍射法对表层残余应力进行检测。结果表明:残余应力在焊缝两侧不对称分布,峰值应力出现在搅拌针轴肩与试样接触区域,残余应力在搅拌针作用区出现“凹点”;超声冲击对接头残余应力分布影响显著,在焊趾处引入超过-100 MPa的压应力,降幅超过120%;随着激励电流增加,搅拌针作用区内的残余压应力增大。To address the design requirement of low residual stress enhanced service reliability in friction stir welding(FSW)for launch vehicle storage tank of aluminium alloy,the residual compressive stress induced by ultrasonic impact treatment(UIT)was put forward to control the welding stress distribution in this paper.The 2219 aluminium alloy weld joint by FSW was treated by ultrasonic impact with different excitation current,and the residual stress was measured by X-ray diffraction.The experiment results showed that distribution of residual stress across the weld was asymmetrical with peak stress observed at the interface between the shoulder of the stirring pin and the specimen.Notably,the"concave point"of residual stress value in the stirring pin's affected zone was found.The UIT made obvious effects on the residual stress distribution of the joint,and introduced compressive stress at the weld toe exceeding-100 MPa and achieved a reduction greater than 120%.Furthermore,the residual compressive stress within the stirring pin region exhibits an was increased with higher excitation currents.

关 键 词：超声冲击 搅拌摩擦焊 X射线衍射 残余应力 

分 类 号：TG453.9[金属学及工艺—焊接]