工艺参数对Ti/Zn/Al异种金属搅拌摩擦焊接头力学性能的影响

Effect of Process Parameters on Mechanical Properties of Ti/Zn/Al Joint Welded by Friction Stir Welding

以3 mm厚2A14铝合金和TC4钛合金为对接材料,0.05 mm厚Zn薄片为中间层材料进行搅拌摩擦焊对接。研究了不同焊接参数对钛/铝异种金属搅拌摩擦焊对接接头宏观形貌、微观组织、力学性能的影响。结果表明:当焊接速度为75 mm/min,旋转速度为375~950 r/min,偏移量2.5 mm时,均可获得表面成形良好的焊接接头。但随着旋转速度的增加,焊缝表面粗糙度先减小后增大,而对接接头抗拉强度逐渐降低;当旋转速度为600 r/min,焊接速度从60mm/min增大到95 mm/min时,焊缝的飞边逐渐减少。当旋转速度为375 r/min,焊接速度为75 mm/min,偏移量2.5 mm时,抗拉强度达到最大值237.3 MPa,达铝合金母材抗拉强度的56.7%。

2A14 aluminium alloy of 3 mm in thickness and TC4 titanium alloy were welded by friction stir welding（FSW） with a 0.05 mm Zn ribbon as the intermediate layer. The effects of process parameters on macro-morphology, microstructure and mechanical properties of the joints were studied. The results indicate that the well-formed joints can be fabricated by friction stir welding with the parameters of welding velocity 75 mm/min, rotation speed 375~950 r/min and offset 2.5 mm between the center of pin and interface of the two plates. The surface roughness decreases and then increases with the rotation speed increasing, while the tensile strength of the joints decreases gradually. However, as the welding velocity increases from 60 mm/min to 95 mm/min, the fins of the weld become less gradually. When the welding velocity, rotation speed and offset are 75 mm/min, 375 r/min and 2.5 mm, respectively, the maximum tensile strength is up to 237.3 MPa, nearly 56.7% of that of the aluminum alloy.