高速超威弧MIG焊下TC4/5A06接头界面组织特性  

Interfacial Microstructure of TC4/5A06 Al Joint Using High Speed Force Arc MIG Welding

作　　者：刘李宾 魏守征[1] 王建宏[1] 李志勇[1] 张英乔[1] 李玉新[1] LIU Libin;WEI Shouzheng;WANG Jianhong;LI Zhiyong;ZHANG Yingqiao;LI Yuxin(Welding Research Center,North University of China,Taiyuan,030051)

机构地区：[1]中北大学焊接研究中心,太原030051

出　　处：《焊接学报》2023年第11期80-87,I0007,共9页Transactions of The China Welding Institution

基　　金：国家自然科学基金项目(51805492);金属凝固控制与精确成形山西省重点实验室基金项目(MSPM202005)。

摘　　要：采用填充SAl5183焊丝和高速超威弧MIG焊方法对TC4钛合金和5A06铝合金进行了熔钎焊,采用SEM、XRD及拉伸测试等分析了焊接热输入E对TC4/5A06接头组织性能的影响规律.结果表明,在试验参数条件下,热输入E对TC4/5A06界面显微组织和接头的力学性能具有明显影响:当热输入E≤0.93 kJ/cm时,接头根部存在未熔合缺陷,TC4/5A06界面处形成了一层厚度不足1μm的TiAl3;当热输入E≥1.20 kJ/cm时,焊缝出现了熔穿缺陷,接头上部和中部的TC4/5A06界面处形成了厚度在2.5~6μm的TiAl3+Ti3Al双层结构,其它区域则形成一层厚约1μm的TiAl3;热输入E在1.02~1.11 kJ/cm范围内时,焊缝成形良好,TC4/5A06界面处形成厚度在0.7~1.5μm的单层TiAl3.在选择的工艺范围内,接头的平均抗拉强度随E的增大而逐渐增大,在不出现成形缺陷的条件下,抗拉强度最高可达232 MPa.High speed force arc MIG welding of TC4 Ti to 5A06 Al was carried out using SAl5183 filler.The effect of welding heat input E on the joint microstructures and properties was analyzed by SEM,XRD and tensile test.The results showed that E has a significant influence on the microstructure and mechanical properties under the test process conditions:lack of fusion occurred at the root part with the E lower than 0.93 kJ/cm,a single TiAl3 layer with the thickness of less than 1μm was formed at the Ti/Al interface.Burn through occurred with the E exceeded 1.20 kJ/cm,a TiAl3+Ti3Al double-layered structure with the thickness of 2.5~6μm was formed at the top and middle parts,while a single TiAl3 layer with the thickness of about 1μm was formed at other parts.When E is in the range of 1.02−1.11 kJ/cm,the joint was well formed and a TiAl3 layer with the thickness of about 0.7−1.5μm was formed at the Ti/Al interface.In the selected processing range,the average tensile strength of the joint increases gradually with the increase of E,the ultimate tensile strength for the joints absent of forming defects can reach 232 MPa.Highlights:(1)Effective bonding between TC4 Ti and 5A06 Al was achieved by using high speed force arc MIG welding,a welding-brazing bonding mechanism was revealed.(2)The microstructural characteristics of Ti/Al interface under the high speed force arc MIG welding was revealed by the analysis of the joint microstructures.

关 键 词：钛合金 铝合金 高速焊 超威弧MIG焊 显微组织 

分 类 号：TG457.19[金属学及工艺—焊接]