非均质厚壁球壳液压胀形过程有限元模拟

FEM simulation of hydrobulging thick spherical vessels with consideration of weld seams

对非均质厚壁球壳液压胀形过程有限元模拟进行了研究 ,探讨了壳体液压胀球过程中的应力应变的分布规律。研究结果表明 :随着屈服强度比Yr 增大 ,焊缝的内侧应力变化梯度增大 ,热影响区的应力梯度明显增大 ;最大等效应力点的位置逐渐由热影响区转换到焊缝 ;应变由焊缝向热影响区转移 ,即热影响区的相对应变增大 ,应变由内向外逐渐变小 ,但应变梯度的变化较小。

FEM simulation has been carried out for hydrobulging thick spherical vessels with investigation of stress and strain distribution which has shown that with the increase of the yielding stresses ratio, the stress gradient of the inner surface will increase and the position with the peak effective stress will move from the hot affected zone (HAZ) to the welds, the strain will move to the HAZ, i.e., the relative strain on the HAZ will increase, the strain will decrease gradually from the inner surface to the outer surface, the change of the strain gradient decrease.