【摘要】 采用真空电子束熔丝沉积制备TA7-TC4双钛合金试样，通过对电子束增材制造双钛合金在TC4侧、TA7侧以及中间过渡区的组织特征进行研究，分析合金的组织结构、硬度、力学性能、断裂方式及断口形貌。结果发现，双钛合金TA7侧内部组织晶粒主要以块状α组织为主，TC4侧可以看到明显的针状马氏体转变相垂直过渡层生长且在过渡层断开，存在明显各向异性；TA7-TC4双钛合金沉积试样力学性能介于TA7与TC4两种合金之间，塑性相对较好；双钛合金沉积试样的硬度顺序为：TA7侧<过渡区<TC4侧；断口分析发现，过渡层界限清晰，断面呈杯锥状，剪切断裂明显。更多还原

【Abstract】 TA7-TC4 bi-titanium alloy specimens were prepared by vacuum electron beam fusion deposition, and the microstructure characteristics at TC4 side, TA7 side and intermediate transition zone were investigated. Microstructure, hardness, mechanical properties, fracture mode and fracture morphology of Ti alloy were analyzed. The results indicate that the internal grain of alloy at TA7 side is mainly composed of massive α structure, and the vertical transition layer of acicular martensite transformation phase is observed on the TC4 side with obvious anisotropy in the transition layer. The mechanical properties of TA7-TC4 bititanium alloy are between those of TA7 and TC4 alloys, and the plasticity is satisfied. The hardness of specimens deposited by bi-titanium alloy is as follows: TA7 side < transition zone < TC4 side. Fracture analysis reveals that the boundary of transition layer is clear, and the section presents cupshaped with significant shear fracture.更多还原