韧性断裂准则在高强钢板料成形中的应用

 针对板料成形中的韧性断裂准则预测成形极限的方法,进行了综述和分析,提出了利用韧性断裂准则能够较好地预测塑性差的板料成形极限,而且还能考虑应变路径的变化．将Cockroft和Latham准则应用到高强度钢板DP590的成形预测中．对高强钢DP590进行了单向拉伸试验,获得了相应的物性参数．同时对该高强钢进行了方盒件成形试验,并进行了相应的有限元模拟．通过对高强钢的极限试验,利用有限元模拟获得了该材料的Cockroft和Latham准则常数．最后利用该常数对方盒件的拉深过程进行了缺陷的预测,模拟结果和试验结果完全吻合．表明韧性断裂准则是可以应用到高强度钢板的成形中的．

Research on application of ductile fracture criteria in sheet metal forming process of high strength sheet

The paper overviews the methods of predicting forming limit in sheet metal forming. By utilizing ductile fracture criteria(DFC)， the method to well predict the forming limit was proposed and furthermore， it considered the change of forming path as well. The Cockroft and Latham criteria were applied in the forming of high strength steel(HSS) DP590. The unidirectional stretching experiment was done on DP590 steel to obtain the corresponding physical parameters. Moreover， the rectangular cup experiment was conducted to get the forming limit parameters and corresponding finite element simulation was done. Cockroft and Latham criteria parameter of this material was obtained through finite element simulation. Finally， by employing these criteria parameters， the fracture was predicted in the cup forming. The results accord well with the experiment. It is demonstrated that DFC can be applied in HSS forming．