多晶体材料微结构循环弹塑性性质的数值统计分析

应用宏，微观相结合的分析观点，在概率计算几何方法基础上构造材料微结构的几何网络，均匀随机投放各晶粒的材料主轴方向，从而形成计算微观力学分析模型。用多域弹塑性边界元方法计算材料微结构的循环应力应变响应，对多晶体的循环硬化量，循环屈服应力增量，Ｂａｕｓｃｈｉｎｇｅｒ效应进行数值统计分析，获得了其变化规律。

NUMERICAL STATISTICAL ANALYSIS ON CYCLIC ELASTOPLASTIC BEHAVIORS OF POLYCRYSTALLINE AGGREGATES OF METALLURGICAL MATERIALS

In light of macro and microscopical combination methodology,the cyclic stress and strain behaviors of the polycrystalline aggregates of metallurgical materials are studied by applying multi regional elastoplastic boundary element method.The model of micromechanics to aggregate structures is constructed on the base of probabilistic arithmetic geometry methods and uniformly random arrangement of material principal directions of crystal cells.Some typical features of cyclic stress and strain behaviors,such as cyclic hardening iue life under variable amplitude loading is obtained. The results also show that the fatigue life and the accumulative fatigue damage of 15MnVN steel notched specimens both follow the log. normal distribution.