基于热-力耦合和变摩擦因数的高强钢冷冲压成形性

测定了DP780高强度双相钢在不同温度下的摩擦因数，建立了变摩擦因数模型,研究了热-力耦合和变摩擦因数对室温冷成形的影响。结果显示，热变组仿真分析 部分区域温度明显升高，相比参照组相同区域，板料减薄程度更小，不易开裂，表现出更好的延展性。从回弹偏移量看，热变组的值比冲压实验测量值偏小，而参照组的值偏大，且相比冲压实验测量值的误差，热变组仅为参照组的27.8%，与冲压实验符合度更好。

Formability of HSS in Cold Stamping Based on Variable Friction Coefficient and Thermal-mechanics Coupling

Measured friction coefficient of DP780 dual phase HSS under  different temperatures，a novel variable friction coefficient model was  established，and the formability during room temperature cold stamping   was researched based on thermal-mechanics coupling and variable friction  coefficients.The results show that temperature is increased obviously in  some areas of sheet metal in heat variable（HV） groups，and comparing the  same places with compared groups，the thinning ratio is smaller，not easy  to crack，better ductility are showed.From spring-back displacement  contour，values in HV groups  are smaller than the measured values in  stamping experiments.However values in compared groups are bigger，and  compared with the experimental measured values，the errors of HV groups  are only 27.8%   of compared groups，and are agreed with stamping  experiments better.