以真空熔敷Cu-Ni-Fe涂层为先导的钨/铜扩散连接

Tungsten/Copper Diffusion Bonding Guided by Vacuum Deposited Cu-Ni-Fe Coating

采用真空熔敷法在纯钨表面制备Cu-Ni-Fe涂层,以此涂层为中间层,实现纯钨与铜的扩散连接。利用光学显微镜、扫描电镜、能谱仪、显微硬度计及剪切试验等方法,研究钨/Cu-Ni-Fe涂层/铜连接接头的界面显微组织特征及成分分布。结果表明:真空熔敷所形成的钨/Cu-Ni-Fe涂层界面中,大量W原子以反应扩散形式进入Cu-Ni-Fe涂层,形成宽约6μm的界面富FeW层;后续扩散连接所形成的Cu-Ni-Fe涂层/铜界面中,除了母材紫铜中存在少量微孔外,界面组织均匀致密;钨/Cu-Ni-Fe涂层/铜连接接头的剪切强度达到185MPa,断裂失效发生在钨母材和界面富FeW层中。

Cu-Ni-Fe coating was prepared on the surface of pure tungsten by vacuum deposition,and the dif fusion bonding of pure tungsten and copper was carried out with the coating as the middle layer. The mi crostructure and composition distribution at the interface of the W/Cu-Ni-Fe coating/Cu joint were investigated by OM, SEM, EDS, microhardness tester and shear test. The results show that at the interface of vacuum deposited W/Cu-Ni-Fe coating,a large number of W atoms go into the Cu-Ni-Fe coating by reaction diffusion to form a 6μm wide FeW-rich interracial layer. At the Cu-Ni-Fe coating/Cu interface formed during diffusion bonding, the microstructure is homogeneous and compact but copper base metal has a small amount of micropores. The shear strength of the W/Cu-Ni-Fe coating/Cu joint reaches 185 MPa,and fracture failure occurs mainly in tungsten base metal and FeW-rich interracial layer.