工艺参数对钛/铝搅拌摩擦点焊成形及拉剪性能影响

Influence of Welding Process Parameters on Joint Surface Topography and Tensile Shear in Friction Stir Spot Welding of Ti/Al

对3 mm厚的TC4钛合金和3 mm厚的2A14铝合金进行直插式搅拌摩擦点焊试验,通过对各种工艺条件下的点焊接头焊点表面形貌观察和剪切拉伸试验。分析了不同工艺参数对点焊接头形貌和拉剪性能的影响。结果表明:在本次试验研究范围内,随着搅拌头旋转速度、轴肩下压量和停留时间等工艺参数变量的增加,焊点表面成型变好;当工艺参数增加的过大时,焊点表面成型又会重新变差。搅拌头旋转速度、轴肩下压量和停留时间等工艺参数对点焊接头剪切拉伸强度的影响都是随着该变量的增加呈现先增大后减小趋势;当搅拌头旋转转速为950 r/min、停留时间为9 s和轴肩下压量为0.3 mm时,焊点表面成型较好,此时接头的剪切拉伸载荷达到最大值,为7.262 k N。

The friction stir spot welding of 3 mm thick sheets of 2A14 aluminum alloy and 3 mm thick sheets of TC4 titanium alloy was conducted using tool with cylindrical pin. The influences of welding process parameters on the tensile shear properties and surface topography joints of friction stir spot welding were investigated under various process parameters of spot welding joints surface morphology observation and shear tensile test~ The results show that：within the scope of the experiment, with the increase of tool rotation speed, the tool penetration depth, and welding time, the surface shaping becomes better. When process parameters increase too large, the surface shaping gradually becomes poor again. With the increase of tool rotation speed, the tool Penetration depth, welding time, the tensile shear increasesm first, and then reduces. The tensile shear tests show that optimized friction stir spot welding process parameters is that when the rotary speed reaches 950r/min and pressed shoulder depth 0.3mm with the holding time 9s, the surface topography of spot-welded joint is good, and the maximum shear strength of the welded joint can be realized and the maximum shear strength is 7.262 kN.