摘要
采用具有不同Si含量的1070,4043和4047三种焊丝对5A06/2219铝合金进行了焊接,对比了不同焊丝条件下的裂纹倾向性。通过光学显微镜(OM)、扫描电子显微镜(SEM)以及能谱分析(EDS)对不同Si含量的异种铝合金焊接接头的显微组织及裂纹断口进行了观察,并对异种铝合金焊接裂纹萌生机理进行了讨论。结果表明,当采用Si含量较高的4047焊丝进行焊接时,5A06/2219异种铝合金焊接接头无明显焊接裂纹;当采用1070进行焊接时,焊接裂纹出现在近2219侧的焊缝;当采用4047进行焊接时,焊接裂纹出现在近焊缝中心位置。通过对裂纹断口进行观察可知,焊接裂纹均属于典型的结晶裂纹,晶界析出的低熔点共晶Al_2Cu是产生结晶裂纹的主要原因。
5 A06/2219 aluminum alloy was welded by 1070,4043 and 4047 filler wires with different Si content,respectively,and the influences of Si content on the welding crack sensitivity were studied. The microstructure and crack fracture of different welding joints were observed by optical microscopy( OM),scanning electron microscopy( SEM) and energy spectrum analysis( EDS),and the crack initiation of dissimilar aluminum alloy welded joints was discussed. Compared with the welded joint obtained by 4047 filler wire,the obvious cracking tendency can be found in dissimilar welded joints obtained by 4043 and 1070 filler wire. The welding crack belongs to solidification crack and Cu Al2 eutectic phase plays a dominant role in crack initiation process.
作者
宋建岭
李庆庆
刘含伟
肖宏
林三宝
Song Jianling;Li Qingqing;Liu Hanwei;Xiao hong;Lin Sanbao(Tianjin Long March Launch Vehicle Manufacturing Co.,Ltd.,Tianjin 300462,China;State Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology,Harbin 150001,China)
出处
《焊接》
2019年第2期35-39,67,共6页
Welding & Joining
基金
国家科技重大专项资助项目(2018ZX04013001)
关键词
异种铝合金
SI元素
显微组织
裂纹
dissimilar aluminium alloy
Si element
microstructure
welding cracks
作者简介
第一作者:宋建岭,1982年出生,博士,高级工程师;主要从事航天运载火箭燃料贮箱的焊接工作,已发表学术论文30余篇,申请国家发明专利10余项。
