焊点形状对TC4钛合金激光点焊力学性能的影响

Influence of Different Shapes on the Mechanical Properties of Laser Spot Weld of TC4 Titanium Alloy

设计了四种不同形状的焊点并进行TC4钛合金搭接接头激光非穿透焊工艺试验。研究了不同焊点的抗剪性能差异,分析了典型焊点的断裂行为及其原因。结果表明,焊点的抗剪载荷与熔合面面积有关;双排断续焊点在同等的熔合面面积下具有最大的抗剪载荷;焊点的断裂方式有界面断裂和横截面断裂两种;相对于双排断续焊点,C形焊点焊后残余应力的存在使得端点处应力集中进而降低了接头静载性能。

Four different shapes of weld are designed to execute the experiment of non-penetration welding of TC4 titanium alloy. Shear performance and fracture behavior of different welds are mainly researched. The shear performance has a relationship with the area of fusion surface. The double row of stitch weld has the highest shear performance. The weld will depart from the interface or break along the cross-section at the endpoints. The existence of the residual stress leads the stress concentrating at the endpoints and subsequently descends the static performance of C weld with respect to double row of stitch weld.