初始损伤非均匀性条件下的材料细观损伤演化

The Meso-damage Evolution of Metal for the Initial Void Inhomogeneity

采用孔洞群三维体胞模型对孔洞大小及分布非均匀性情况下的材料损伤进行模拟计算。结果表明 :孔洞非均匀性增强了局部的孔间干涉作用和孔洞的长大 ,引起材料损伤局部特性不均 ,表明非均匀细观结构较均匀化假设更易于造成材料的损伤和破坏 ;Gurson修正模型中采用常系数 q1 和 q2 描述孔间干涉作用是不够准确的 ,q1 、q2 是一个逐渐增大的变化量。

In this paper, three-dimensional cell model containing clustering voids is built to study the meso-damage evolution of metal considering the void size and distribution inhomogeneity. It is found that the interaction effect and the growth rate of closing voids are increased due to the void inhomogeneity. It means that the inhomogeneity of void distribution can result in localizing inhomogeneity of meso-damage evolution of metals that will cause the damage and failure of metals much easier than the homogeneous void distribution. In addition, the parameters q 1 and q 2 of Gurson modification model should be increasing variables rather than constant ones.