热输入对电机支架不同位置V型接头焊接热循环和残余应力的影响

Effect of Heat Input on Welding Thermal Cycle and Residual Stress of V-joints at Different Positions of Motor Bracket

摘要: 利用非线性有限元软件Marc建立含6处V型接头的管状电机支架模型，模拟研究了热输入对6处V型接头起弧端热循环以及焊缝区残余应力的影响。结果表明：热输入越高，起弧端温度峰值越高，接头在加热和冷却过程中的受热越均匀；热输入对焊缝前端和末端焊接残余应力的影响较小；对于焊缝中段，热输入越大，焊接残余应力越小，并且除了接头Ⅱ外，其他接头焊缝中段残余应力均表现为拉应力。

Abstract: A tubular motor bracket model with six V-joints was established with a nonlinear finite element software Marc.The influence of heat input on the thermal cycle at the arcing end and the residual stress in welds of six V-joints were simulated and studied.The results show that the higher the heat input, the higher the peak temperature at the arcing end, and the more uniform the heat of the joint during heating and cooling processes.The heat input had a small effect on the welding residual stress at the front and end of the welds.For the middle of the welds, the greater the heat input, the smaller the welding residual stress; except for the joint II, the residual stresses in the middle of welds of other joints were all tensile stresses.