【摘要】 以弹塑性有限元基本方程为基础 ,引入等效应变并采用与弹性损伤模量相关的塑性流动法则 ,得到对称弹塑性损伤刚度矩阵 .根据损伤应变能释放率与损伤变量的对偶关系 ,提出损伤耗散势的幂率形式 ,导出了损伤演化规律 .将此理论方法用于圆盘的深拉延数值分析 ,给出由损伤所引起的材料性能退化对冲头力的影响 ,得到损伤演化规律 .更多还原

【Abstract】 Based on the ductile fracture caused by micro void nucleation, growth and coalescence into micro crack, an isotropic damage model is proposed and coupled with elasto plastic constitutive equation. The analysis of finite element is coded with FORTRAN language and applied to analyze the deep drawing of cylindrical cup. Effect of materical degenetation caused by damage on punch force is described. Damage is obtained and the numerical calculation for punch force shows good agreement with the experimental measure.更多还原