316L不锈钢T型接头温度场与应力场数值模拟

Numerical Simulation of Temperature Field and Stress Field of T-joint of 316L Stainless Steel

运用SYSWELD模拟软件分析了316L不锈钢T型接头的温度场与应力场,并利用试验方法对模拟结果进行了验证。试验结果与数值模拟结果吻合良好,证实了模拟316L T型接头的可靠性。结果表明,T型接头截面温度分布由扇形分布向椭球状分布转变,且随着焊接道次的增加,温度分布区域增加;焊接时温度场沿焊缝中心呈对称分布,其焊缝区与母材区温度差异较大;第2道焊接的温度峰值明显最大,其腹板温度的峰值温度明显高于翼板的峰值温度,且随着离焊缝越远,其热循环曲线变化越小;不论是纵向残余应力还是横向残余应力,其沿焊接方向上均呈帽状分布,最大纵向残余拉应力出现在焊缝中部,而最大横向残余应力出现在靠近中部焊缝位置;垂直于焊缝的纵向残余应力和横向残余应力均表现出近焊缝区较大拉应力。

The temperature field and stress field of T-joint of 316 L stainless steel were analyzed by using SYSWELD simulation software, and the simulation results were verified by the experimental results. The numerical simulation results were in good agreement with the experimental results, which proved the reliability of the simulation of 316 L T-joint. The results shows that the temperature distribution of cross-section of T-joint is changed from fan-shaped distribution to elliptical distribution. With the increase of welding pass, the area of temperature distribution increases. The temperature field distribution is symmetric along the center of the weld during welding, the temperature difference between the weld zone and the parent metal zone is large. The temperature peak value of the second weld is the largest, the peak temperature of the web is significantly higher than that of the wing, and the farther the distance from the weld is, the smaller the change of thermal cycling curve is. Longitudinal residual stress and transverse residual stress all show hat-like distribution along the welding direction, and the maximum longitudinal tensile residual stress appears in the middle of the weld, the maximum transverse residual stress appears near the central position of the weld. Both the longitudinal residual stress and the transverse residual stress perpendicular to the weld is large tensile stress near weld zone.