7075/TC4异种金属CMT Advanced+P熔钎焊特性分析  

Analysis of CMT Advanced+P welding-brazing characteristics of 7075/TC4 dissimilar metals

作　　者：吕小青[1,2] 鲁硕 徐连勇[1,2] 荆洪阳[1,2] 韩永典[1,2] LV Xiaoqing;LU Shuo;XU Lianyong;JING Hongyang;HAN Yongdian(Tianjin University,Tianjin 300072,China;Tianjin Key Laboratory of Advanced Joining Technology,Tianjin 300072,China)

机构地区：[1]天津大学,天津300072 [2]天津市现代连接技术重点实验室,天津300072

出　　处：《焊接学报》2021年第2期1-7,I0001,共8页Transactions of The China Welding Institution

基　　金：国家自然科学基金面上项目(52075372)。

摘　　要：基于CMT Advanced+P焊接方法,以ER5356铝合金焊丝对7075铝合金和TC4钛合金组成的搭接接头进行熔钎焊试验,并对接头进行微观组织及力学性能分析.结果表明,焊接接头主要由焊缝区、铝合金侧热影响区和钎焊界面区组成;焊缝区主要是等轴晶;铝合金侧热影响区的晶粒表现出轧制特性,并在晶界附近析出大量金属间化合物;钎焊界面区存在由钛侧向焊缝区进行生长的锯齿状金属间化合物层,该化合物层厚度1~2.5μm,主要由Al-Ti金属间化合物组成;接头拉伸后断裂位置位于铝合金侧热影响区附近,断裂类型属于混合断裂,最高抗剪强度达到293.1 MPa.Based on CMT advanced+P welding method,the welding-brazing test of 7075 aluminum alloy and TC4 titanium alloy lap joint was carried out using ER5356 filler metal.The microstructure and mechanical properties of the joint were analyzed.The results showed that the welded joint was composed of weld zone,heat affected zone and brazing interface zone.The weld zone was mainly composed of equiaxed grains.The grains in the heat affected zone of aluminum alloy showed rolling characteristics,and a certain amount of intermetallic compounds were precipitated near the grain boundary.In the brazing interface area,there existed a serration-shaped intermetallic compound layer growing from the lateral weld area of titanium.The thickness of the compound layer was 1~2.5μm and mainly composed of Al-Ti intermetallic compounds.The fracture location of the joint was near the heat affected zone of the aluminum alloy,and the tensile fracture type was mixed fracture,with the maximum shear strength of 293.1 MPa.

关 键 词：铝合金 钛合金 冷金属过渡 熔钎焊 

分 类 号：TG444[金属学及工艺—焊接]