超声冲击时间对7A52铝合金VPPA-MIG焊接接头的影响  

Effect of ultrasonic impact time on VPPA-MIG welded joint of 7A52 aluminum alloy

作　　者：陈芙蓉[1] 刘成豪 李男 CHEN Furong;LIU Chenghao;LI Nan(School of Materials Science and Engineering,Inner Mongolia University of Technology,Hohhot,010051,China)

机构地区：[1]内蒙古工业大学,呼和浩特010051

出　　处：《焊接学报》2020年第9期39-43,I0003,共6页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51165026);国家自然科学基金资助项目(51765053).

摘　　要：为研究超声冲击处理时间对7A52铝合金VPPA-MIG复合焊接头的组织及性能的影响,试验对单位面积的焊接接头进行2.5,5,10,15,30和75 min的超声冲击处理.通过观察接头的表面形貌,并对接头进行力学性能测试,以分析超声冲击处理时间对接头的影响.结果表明,7A52铝合金焊接接头超声冲击处理后,接头表面得到了明显强化,在超声冲击时间15 min时焊缝表面晶粒大小达到26.28 nm;在超声冲击时间75 min时焊缝表面硬度为138.8 HV,比原始焊缝显微硬度提高了36.3%;超声冲击处理30 min时残余压应力最大,为243.3 MPa.In order to study the effect of ultrasonic impact time on microstructure and properties of VPPA-MIG composite welded joint of 7A52 aluminum alloy,ultrasonic impact treatment of 2.5,5,10,15,30,and 75 min was carried out on the welded joint per unit area.By observing the surface morphology of the joint and testing the mechanical properties of the joint,the effect of ultrasonic impact treatment time on the joint was analyzed.The results show that the surface of 7A52 aluminum alloy welded joint is obviously strengthened after ultrasonic impact treatment.The grain size of weld surface reaches 26.28 nm when ultrasonic impact time is 15 min;the hardness of weld surface is 138.8 HV when ultrasonic impact time is 75 min,which is 36.3%higher than that of original weld;the maximum residual compressive stress is 243.3 MPa after ultrasonic impact treatment for 30 min.

关 键 词：超声冲击处理 铝合金 变极性等离子弧-熔化极气体保护复合焊接 显微组织 力学性能 

分 类 号：TG404[金属学及工艺—焊接]