基于延性准则的DP800小圆角拉弯成形开裂判据  

Criteria for fracture predicting of DP800 sheet in small-radius stretch bending

作　　者：尹德友[1] 孙东继[1] 王凯[2] 王武荣[2] 

机构地区：[1]上海通用汽车有限公司,上海201206 [2]上海大学材料学院,上海200444

出　　处：《塑性工程学报》2014年第6期46-50,共5页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(51475280)

摘　　要：针对传统FLC无法准确预测超高强度双相钢薄板在较小凸模圆角下拉弯成形时的剪切开裂问题,采用基于延性准则的成形判据计算其应力-应变失效积分因子,结果表明,使用Brozzo和Oyane延性准则计算的失效积分因子在凸模圆角处超过失效单位值,与试验相符,说明Brozzo、Oyan延性准则能够实现小圆角半径下双相钢板材在拉弯成形中的开裂预测。Since the conventional forming limit criterion （FLC） cannot be used to accurately predict the shear fracture of super strength dual phase （DP） steel sheet in stretch bending with small punch radius ,the ductile criteria were used in this study to cal‐culate the stress‐strain failure integral for key elements under stretch bending limit .The results show that the integral factor cal‐culated by Brozzo or Oyane criterion exceedsthe unit value for the elements around the punch radius ,which indicates fracture fail‐ure at such area and agrees well with the experiment .It can be concluded that ductile criteria proposed by Brozzo and Oyane can be used to predict the shear fracture occurred in the stretch bending of DP sheets under small punch radius .

关 键 词：延性断裂准则 双相钢 剪切断裂 开裂预测 

分 类 号：TG30[金属学及工艺—金属压力加工] TG386.31