层间冷却对多道焊厚板残余应力及变形的影响

Effect of Interlayer Cooling on Residual Stress and Deformation of Multi Pass Welding Thick Plate

基于热弹-塑性有限元原理,使用Marc通用有限元程序对厚板多层多道焊过程进行了数值模拟,计算中考虑了层间不冷却和层间冷却200 s两种工况。结果表明,两种工况下厚板整体变形的最大值分别为0.58和0.65倍板厚;对于两端固支剖面,两种工况下残余应力的峰值分别出现在焊缝中心和固支端;对于两端自由剖面,两种工况下残余应力的峰值均出现在焊缝中心。可见层间冷却主要影响两端固支剖面的残余应力分布,对两端自由剖面残余应力的分布和厚板的整体变形影响不大。

In order to study the influence of interlayer cooling on the residual stress and deformation of multi pass thick plate,based on the principle of thermo elastic-plastic finite element,this paper uses the Marc general finite element program to simulate the process of multi pass thick plate welding.Two working conditions of interlayer non-cooling and interlayer cooling for 200 s are considered in the calculation.The results show that the maximum deformations of the thick plate are 0.58 and 0.65 times of the plate thickness under the two conditions,respectively.For the fixed support section at both ends,the peak values of residual stress under the two conditions appear in the weld center and the fixed support end,respectively.For the free section at both ends,the peak value of residual stress under the two conditions appears in the weld center.It can be seen that interlayer cooling mainly affects the distribution of residual stress in the fixed support section at both ends,but has little effect on the distribution of residual stress in the free section at both ends and the overall deformation of the thick plate.