铝/钛异种金属冷金属过渡熔钎焊接头分析  

Analysis of welding-brazing joints of Ti/Al dissimilar metals obtained by cold metal transfer method

作　　者：孙军浩[1] 曹睿[1] 陈剑虹[1] 

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,兰州730050

出　　处：《焊接学报》2015年第3期51-54,3,共5页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51265028)

摘　　要：以ER4043的铝焊丝对6061铝合金和TA2纯钛进行CMT熔钎焊,采用金相显微镜、扫描电镜(SEM)和能谱分析仪(EDS)分析了焊接接头的微观组织特征,并通过拉伸试验对接头进行了力学性能的评定.结果表明,焊接接头具有熔焊和钎焊双重性质:铝母材局部熔化,与熔化的焊丝金属混合后凝固形成焊缝;而没有熔化的钛母材通过Ti原子的扩散与焊缝金属形成金属间化合物结合层的钎焊界面.钎焊界面处反应层可分为靠近钛板一侧的连续层Ti3Al和向焊缝内部生长的锯齿状的反应层Ti Al3.当钛板坡口角度为30°时,钎焊界面化合物生长均匀良好,接头会断裂在铝母材的热影响区,最高抗拉强度达到197.5 MPa.Cold metal transfer( CMT) welding-brazing of Al6061 and TA2 was carried out using ER4043 filler metal. The microstructure characteristics of the Ti / Al joints were analyzed by optical microscopy,scanning electron microscopy and energy dispersive spectrometer,respectively. Mechanical properties of the joints were characterized by measurement of the tensile strength. The results indicate that a welding-brazing joint was formed by CMT method,which included a welding joint at the aluminium sheet side and a brazing joint at the titanium sheet side. The intermetallic compound at the brazing interface consisted of two different layers. Among them,the continuous layer near titanium substrate was composed of Ti3 Al intermetallic compound,while the serration-shaped layer next to the weld metal was composed of TiA l3 intermetallic compound. When groove angle 30° of titanium sheet was used during the welding process,uniform intermetallics would be formed at the brazing interface,thus sound joint which had a tensile strength of 197. 5 MPa was obtained and the failure location of this joint was at Al HAZ.

关 键 词：铝/钛异种金属 冷金属过渡熔钎焊 金属间化合物 接头强度 

分 类 号：TG454[金属学及工艺—焊接]