Abstract Wire feed speeds of 3.5, 4.5, and 5.5 m/min and offset positions of 1 and 2 were employed for this study with an ERCuSi-A weld wire. The microstructures of the joints, which include a Cu/Ti interface layer consisting of Ti2Cu, TiCu, and AlCu2Ti, a Cu-matrix seam consisting of Cu and petal-shaped Fe-Si-Ti intermetallics, and a Cu/Fe interface layer consisting of α-Fe and Cu, were studied. The formation enthalpy calculated from the Miedema model can explained the microstructure evolution mechanism. The interface thickness and ultimate tensile strength were found to increase with wire feed speed. The highest tensile strength of the joint was 294 MPa, fracturing at the Cu/Ti interface. Offsetting the welding torch to the TC4 side increased the amount and size of the Fe-Si-Ti intermetallics, degrading the tensile strength. Four fracture modes were proposed to differentiate the crack propagations in the joints, which were determined by the interfacial bonding strength and the Fe-Si-Ti intermetallics in the weld seam.

中文翻译：

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钛合金（TC4）与不锈钢（304L）V型槽接头冷金属传递焊接-钎焊的显微组织和力学性能

摘要 本研究采用 3.5、4.5 和 5.5 m/min 的送丝速度和 1 和 2 的偏移位置，使用 ERCuSi-A 焊丝。接头的微观结构，包括由 Ti2Cu、TiCu 和 AlCu2Ti 组成的 Cu/Ti 界面层，由 Cu 和花瓣形 Fe-Si-Ti 金属间化合物组成的 Cu-基体接缝，以及由α-Fe 和 Cu，进行了研究。根据 Miedema 模型计算的形成焓可以解释微观结构演化机制。发现界面厚度和极限抗拉强度随着送丝速度而增加。接头的最高抗拉强度为 294 MPa，在 Cu/Ti 界面处断裂。将焊枪偏移到 TC4 侧会增加 Fe-Si-Ti 金属间化合物的数量和尺寸，降低抗拉强度。