不同焊丝下TC4钛/5A06铝脉冲MIG熔钎焊接头组织性能  

Microstructure and Mechanical Properties of Pulsed MIG Welded-Brazed Ti-TC4/Al-5A06 Joints Using Different Fillers

作　　者：常鸿 魏守征 程璇 李志勇[1] 张英乔[1] CHANG Hong;WEI Shouzheng;CHENG Xuan;LI Zhiyong;ZHANG Yingqiao(School of Materials Science and Engineering,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学材料科学与工程学院,山西太原030051

出　　处：《电焊机》2025年第3期88-95,共8页Electric Welding Machine

基　　金：山西省自然科学基金(202303021211159);山西省自然科学基金(202203021222036)。

摘　　要：采用纯铝、Al-Si5、Al-Mg5三种焊丝对TC4钛和5A06铝进行脉冲MIG熔钎焊,研究焊丝成分对接头Ti/Al界面特性及力学性能的影响。结果表明:采用纯铝焊丝时,钛与铝基焊缝通过形成芽状界面反应层单层结构实现冶金结合,接头上部反应层宽约3μm,接头根部反应层宽约0.5μm。采用Al-Si5焊丝时,接头上部钛与焊缝之间形成均匀层+芽状反应层双层结构实现结合,宽约5μm;接头根部形成芽状反应层单层结构,宽约1μm。采用Al-Mg5焊丝时,接头上部钛与焊缝之间形成宽约5μm的均匀层+芽状反应层双层结构,接头根部仅形成宽约0.5μm的芽状反应层单层结构。拉伸测试中,采用纯铝焊丝制备的接头抗拉强度为92~94 MPa,接头断裂于铝基焊缝,呈韧性断裂方式;采用Al-Mg、Al-Si焊丝时,所获接头抗拉强度分别为196 MPa、230 MPa,接头均断裂于Ti/Al界面附近,呈脆性+韧性混合断裂方式。实施钛与铝熔钎焊时,应选择熔敷金属强度较高、韧性较好的Al-Mg/Al-Si系合金焊丝作为填充金属。Pure aluminum,Al-Si5 and Al-Mg5 wires were used for pulse MIG brazing of TC4 titanium and 5A06 aluminum.The effect of wire composition on the Ti/Al interfacial characterizations and joint mechanical properties was investigated.When pure aluminum wire was used,titanium and aluminum-based weld were metallurgical bonded by the formation of a bud-shaped interfacial reaction layer,the width of the layer is about 3μm at the joint upper part and 0.5μm at the root part.When Al-Si5 wire was used,a double-layer structure with a width of 5μm containing a homogeneous layer and a budshaped layer was formed between titanium and weld at the upper part of the joint.However,only a bud-like reaction layer with the width of 1μm was formed at the root part.When Al-Mg5 wire was used,similarly,a double-layer structure with a width of 5μm containing a homogeneous layer and a bud-shaped layer was formed at the upper part of the joint.a bud-like reaction layer with the width of 0.5μm was formed at the root part.The tensile strength of the joint fabricated using pure aluminum wire was 92~94 MPa,the joint was fractured in the aluminum-based weld and taking the plastic fracture mechanism.However,When Al-Mg and Al-Si wires were used,the tensile strength of the joints was 196 MPa and 230 MPa,respectively.The joints were fractured near the Ti/Al interface and taking the brittle+plastic mixed fracture mode.When implementing titanium and aluminum melting brazing,the filler metal with higher strength and better toughness of the Al-Mg/Al-Si alloy welding wire should be selected as the filling metal.

关 键 词：焊丝成分 钛合金 铝合金 熔钎焊 界面特性 力学性能 

分 类 号：TG457.1[金属学及工艺—焊接]