为了获得高强度T2铜和Ti-6Al-4V钛合金异种金属接头，采用电子束焊方法开展试验，并对接头界面组织及力学性能进行了分析.试验在钛/铜熔钎焊接基础上，通过在高熔点钛侧复合二次焊接，构建钛/铜结合界面金属间化合物层的重熔温度场，进而实现钛/铜金属间化合物层的重熔改性.通过有限元温度场模拟及SEM，XRD等检测.结果表明，钛侧重熔焊接可在结合界面处形成1 000℃左右高温，金属间化合物层发生局域重熔.在随后凝固过程中，由于散热方向及元素再分配，相的形成顺序发生改变，钛原子向铜侧的扩散距离减短，高硬度相TiCu向Ti2Cu转变，相结构优化，最终接头强度得以提升.
In order to obtain high-strength dissimilar metals joints of T2 copper and Ti-6Al-4V titanium alloy, electron beam welding was used to carry out experiments, and the interfacial microstructure and mechanical properties of the joints were analyzed. Based on the Ti/Cu welding-brazing process, the remelting temperature field of intermetallic compounds layer at the Ti/Cu bonding interface was constructed by secondary composite welding on the Ti side of high melting point, and then the remelting modification of Ti/Cu intermetallic compounds layer was realized. By temperature field simulation of FEM and detection of SEM, XRD, the results shown that a high temperature of about 1 000℃ at the interface was formed by remelting welding at titanium side, leading to local remelting of intermetallic compound layer. In the process of solidification, due to the direction of heat dissipation and the redistribution of elements, the formation sequence of the phase was changed, the diffusion distance of titanium atoms was reduced and TiCu with high hardness was transformed to Ti2Cu. The phase structure was optimized and finally the strength of the welded joints improved.
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