摘要
基于连续介质损伤力学 ,提出了描述金属板材塑性损伤的演变方程 ,并依此得到了一个用于预测金属板材断裂破坏的简单准则 .其中特别考虑了剪切机制和剪切应力在金属薄板损伤发展和最终破坏过程中的作用 ,同时也引入了材料微观损伤对材料机械性能的影响 .提出的损伤演变规律 ,可近似表征金属薄板在成型过程中损伤的发展变化 ,计算得出的损伤曲线与有关实验曲线比较吻合 .给出的损伤破坏准则 。
Based on the Continuing Damage Mechanics,a simple damage evolution law is proposed for sheet metals,and a failure criterion is then developed,in which the effects of microdefects on the states of stress and strain in materials and on the material properties are taken into consideration.The damage evolution curves for four sheet metals are predicted in terms of the present damage equation,which are in good agreement with the experimental data.Also,the results show that the proposed criterion could be simply used to predict the failure strains of sheet metals and the so called failure limit curves as well.
关键词
金属板材
断裂
材料损伤
连续介质损伤
损伤准则
material damage
CMD(continuing medium damage)
damage criterion
sheet metals
