多晶材料薄壁圆管扭转变形的应力分析

Stress Analysis of Polycrystalline Material Thin-walled Tubes under Torsion Deformation

基于晶体塑性本构关系,编制材料子程序,建立薄壁圆管的多晶集合体模型,研究其扭转变形时宏观响应和细观力学行为,进行了圆管内各晶粒等效应力的统计分析。结果表明:该多晶体圆管模型具有丰富的描述能力;多晶圆管扭转大变形时轴向变形较为显著;圆管内各晶粒内等效应力在统计上具有正态分布的特点。

Based on crystal plasticity constitutive law, a material subroutine(UMAT) was compiled and the polycrystalline aggregates model of thin walled tubes were built, and then the macroscopic response and micromechanics of the thin-walled tubes was researched under torsion deformation. The statistics analyses for the equivalent stress in the grains of tubes were performed. The results show that the polycrystalline thin-walled tube model has good descriptive ability;the axial deformation is obvious when the torsion angular is larger;the equivalent stress in the grains of tube has the statistical feature of normal distribution.