中文摘要：

构建晶粒取向随机分布的多晶集合体，采用晶体塑性本构模型，对多晶材料塑性宏观响应与细观结构的关系进行研究．结果表明：多晶材料细观非均质性对材料的宏观力学行为有重要影响；各晶粒之间的相互约束使得等向强化的晶体本构关系在对多晶材料描述时可以模拟Bauschinger效应；分析Bauschinger效应的机理需综合考虑晶粒之间约束．晶粒的弹性各向异性及不同取向的硬化能力等因素．

英文摘要：

The relationship between macroscopic plastic behavior and microstructure of a polycrystalline aggregate which consists of grains with random orientation was analyzed numerically. The modeling results show that： （1） The microstructure heterogeneousity affects macroscopic mechanic behavior remarkably; （2） The mutual constrains between grains lead to the Bauschinger effect in polycrystals within the framework of single crystal plasticity theory, which is isotropic hardening; （3） The mechanism of the Bauschinger effect depends on several factors such as mutual constrains between grains, crystal elastic orthotropy and hardening of different orientations.