先进高强钢DP780板料的温成形极限预测研究  

STUDY ON WARM FORMING LIMIT PREDICTION OF ADVANCED HIGH STRENGTH STEEL DP780 SHEET METAL

作　　者：王凯迪 李迪[1] 冷杨松 付秋涛 徐家川[1] 姜宁 WANG KaiDi;LI Di;LENG YangSong;FU QiuTao;XU JiaChuan;JIANG Ning(School of Transportation and Vehicle Engineeringy Shandong University of Technology,Zibo 255000,China;Linyi Vocational University of Science and Technology,Linyi 276000,China)

机构地区：[1]山东理工大学交通与车辆工程学院,淄博255000 [2]临沂科技职业学院,临沂276000

出　　处：《机械强度》2021年第5期1177-1183,共7页Journal of Mechanical Strength

基　　金：山东省自然科学基金项目(ZR2011EL037)资助。

摘　　要：为准确预测DP780钢板料在温成形条件下的成形极限曲线,将韧性断裂预测模型引入到数值模拟。基于DP780钢板料在温度范围573 K~873 K、应变率范围6.67×10^(-4)s^(-1)~6.67×10^(-3)s^(-1)的单向拉伸试验结果分析,利用强塑积指标确定了温度为673 K、应变率为3.33×10^(-3)s^(-1)条件下材料的温冲压成形性能较好。通过该变形条件下的简单拉伸试验和数值模拟,确定了影响DP780钢板料韧性断裂的主要因素。建立了可以预测DP780钢板料在不同应变路径下发生拉伸型断裂和剪切型断裂两种断裂机制的韧性断裂预测模型,并与温成形本构模型、Hill’48屈服准则相结合实现了刚模胀形试验的数值模拟,预测了DP780钢板料在温度为673 K下的成形极限曲线,并建立了成形极限数学模型。结果表明,利用该方法预测的成形极限结果拥有较好的精度。In order to accurately predict the forming limit curve of DP780 steel sheet under the condition of warm forming,the ductile fracture prediction model was introduced into the numerical simulation.Based on the unidirectional tensile test results analysis of DP780 steel sheet in the temperature range of 573 K~873 K and strain rate range of 6.67×10^(-4)s^(-1)~6.67×10^(-3)s^(-1),the warm forming performance of DP780 steel sheet is better under the condition of temperature of 673 K and strain rate of 3.33×10^(-3)s^(-1) determined by the product of strength and ductility.And through the simple tensile test and simulation under this deformation condition,determined the main factors affecting the ductile fracture of DP780 steel sheet.Thus a model for predicting tensile fracture and shear fracture of DP780 steel under different strain paths was developed,by combining it with the warm forming constitutive model and the Hill’48 yield criterion,the finite element simulation of the rigid mold bulging test was realized,and the forming limit curve of DP780 steel sheet at the temperature of 673 K was predicted,The mathematical model of forming limit was established.The results show that the forming limit results predicted by this method have better precision.

关 键 词：先进高强度双相钢 成形极限 韧性断裂预测模型 数值模拟 温胀形 

分 类 号：TG113.26[金属学及工艺—物理冶金]