【摘要】 <正> 冲压时毛坯内部的应力与应力分布,是确定冲压工艺参数、设计工艺过程和冲模、分析和解决冲压件质量问题的基础,也是冲压变形理论研究工作中最基本的任务。虽然目前有各种塑性力学的理论方法可用来解决这类问题,并形成各种学派[1]、[2]、[3]、[4]、[5]、[6],但因为在计算过程中不得不引入的一些简化(如塑性条件、平衡条件、硬化、毛坯尺寸变化等方面),常常可能造成较大的误差,尤其是在形状复杂的零件成形时,在计算上又可能碰到不易克服的困难,使理论分析方法的运用受到很大的限制。为了解决这个问题,本文提出根据冲压时毛坯各部分尺寸变化的结果,利用变形力学的基本原理确定变形毛坯各部分所受应力的数值与分布规律的方法。在一般情况下,根据全应变理论,三向应力状态下的应力与应变之间存在有如下关系更多还原

【Abstract】 The stress and its distribution inside a blank during pressing are the founda-tion to determine the technological parameters,to design the process and die,toanalyze and to improve the quality of product.In this study,a method ispresented to determine the value and distridution of stresses in various parts ofblank according to the change of blank size during pressing based on fundamentalprinciples of theory of deformable solids.A reasonably complete method oscalculation and fomulae are derivcd based on the relationship between the sfresfand strain during monotonous or nomonotonous loading.This method not onlycan be used to analyze the deformation of concrete part of machine,but also canbe used to determine the law,both in quality and in quantity during pressforming for a certain class of parts.更多还原