CuW70合金与纯铝的连接特性

Characteristic of tungsten copper alloy and pure aluminum joint

采用氩气保护电弧熔焊和钎焊的方式实现对纯铝和CuW70合金的整体连接。利用金相显微镜、XRD、SEM、EDS、显微硬度计和拉压万能试验机等手段研究结合界面的微观组织、相组成、元素分布、力学性能及断口特征。结果表明,利用电弧熔焊和钎焊技术可实现铝材与钨铜假合金的有效连接,2种连接方式在结合界面均形成了"锯齿状"的过渡区,有元素的互扩散现象,存在Cu_(0.4)W_(0.6),CuAl,Cu_9Al_4和CuAl_2等多种固溶体或化合物,过渡区宽约0.5~0.7mm,两者的结合强度约71~95MPa,与铝的强度极限相当。钎焊在连接界面处表现为准解理脆性断裂,电弧熔焊则在界面连接处有钨颗粒的拔出现象。

Argon gas shielded arc welding and brazing were used to join the pure aluminum with CuW70 alloy. The microstructure, phase composition, elemental distribution, fracture characteristics and mechanical properties of the joints interface were studied by metallographic microscope, XRD, SEM, EDS, micro-hardness tester and tension and compression testing machine. The results show that the tungsten copper alloy and pure aluminum can be effective connected by arc welding and brazing technology. The ＂zigzag＂ transition zone is formed in the bonding interface by both two connections, in which the element mutual diffusion phenomenon appears. There existes solid solution or compounds in the bonding interface, such as Cu0.4W0.6, CHAl, Cu9Al4 and CuAl2. The width of the transition zone is 0.5-0.7 mm. The bonding strength between CuW70 alloy and pure aluminum is approximately 71-95 MPa, which is equal to that of pure aluminum. The melting brazing presents quasi-cleavage brittle fracture at connection interface while the arc welding exhibits the phenomenon of tungsten particles being pulled out.