Comparative study on forming limit prediction of AA7075-T6 sheet with M−K model and Lou−Huh criterion  

采用M-K模型和Lou-Huh准则对AA7075-T6板材成形极限预测的对比研究

作　　者：Guo-jiang DONG Zhi-wei CHEN Zhuo-yun YANG Bo-cheng FAN 董国疆;陈志伟;杨卓云;樊博成(燕山大学河北省特种运载装备重点实验室,秦皇岛066004;燕山大学先进锻压成形技术与科学教育部重点实验室,秦皇岛066004)

机构地区：[1]Hebei Key Laboratory of Special Delivery Equipment,Yanshan University,Qinhuangdao 066004,China [2]Key Laboratory of Advanced Forging&Stamping Technology and Science of Ministry of Education of China,Yanshan University,Qinhuangdao 066004,China

出　　处：《Transactions of Nonferrous Metals Society of China》2020年第6期1463-1477,共15页中国有色金属学报（英文版）

基　　金：Project (51775481) supported by the National Natural Science Foundation of China;Project (E2019203418) supported by the Natural Science Foundation of Hebei Province, China;Project (ZD2017078) supported by the Science and Technology Plan of Hebei Higher School of Education Department, China。

摘　　要：In order to effectively predict the fracture of AA7075-T6 sheet, the forming limit curves of AA7075-T6 high-strength sheet were drawn according to Morciniak Kuczyski (M K) model and Lou Huh criterion, respectively. The errors between the predicted values of the two theoretical prediction models and experimental values were calculated by error analysis. The forming limit curves were verified by the punch stretch test to evaluate the prediction accuracy of M K model and Lou Huh criterion. The error analysis results show that the mean error of Lou Huh criterion with the optimal parameters for all tensile specimens is 25.04%, while the mean error of M K model for all tensile specimens is 74.24%. The prediction accuracy of Lou Huh criterion in predicting the fracture of AA7075-T6 sheet is higher. The punch stretch test results show that the forming limit curve drawn by Lou Huh criterion can effectively predict the fracture of AA7075-T6 sheet, but the prediction accuracy of M K model is relatively poor.为了能够有效预测AA7075-T6高强铝板的破裂,依据Morciniak-Kuczyski模型(M-K模型)与Lou-Huh准则分别绘制AA7075-T6高强铝板成形极限曲线,通过缺口试样误差评估比较两种理论预测模型预测值与试验值之间的相对误差,并通过半球形刚模胀形试验对两种理论预测模型绘制的成形极限曲线进行验证,以此评价M-K模型与Lou-Huh准则的预测精度。由误差分析可知,采用最优断裂参数的Lou-Huh准则对各拉伸试样的误差均值为25.04%,而M-K模型对各拉伸试样的误差均值达到74.24%,Lou-Huh准则对AA7075-T6板材的破裂预测精度较高。半球形刚模胀形试验验证结果表明,用Lou-Huh准则绘制的成形极限曲线能够有效预测AA7075-T6板材的破裂,而M-K模型构建的成形极限曲线预测结果较差。

关 键 词：ductile fracture criterion M K model forming limit diagram AA7075-T6 sheet 

分 类 号：TG146.21[一般工业技术—材料科学与工程]