DP780双相钢U弯回弹预测影响因素研究  

Study on Influencing Factors of U-bending Springback Prediction of DP780 Dual-phase Steel

作　　者：郑学斌 韩龙帅 李学涛 鄂宏伟 吴向东[1] 万敏[1] ZHENG Xuebin;HAN Longshuai;LI Xuetao;E Hongwei;WU Xiangdong;WAN Min(School of Mechanical Engineering&Automation,Beihang University,Beijing 100191;Research Institute of Technology,Shougang Group Co.,Ltd.,Beijing 100043;Beijing Key Laboratory of Green Recyclable Process for Iron and Steel Production Technology,Beijing 100043;Beijing Engineering Research Center of Energy Steel,Beijing 100043;School of Mechanical Engineering,Yanshan University,Qinhuangdao 066004)

机构地区：[1]北京航空航天大学机械工程及自动化学院,北京100191 [2]首钢集团有限公司技术研究院,北京100043 [3]绿色可循环钢铁流程北京市重点实验室,北京100043 [4]北京市能源用钢工程技术研究中心,北京100043 [5]燕山大学机械工程学院,秦皇岛066004

出　　处：《机械工程学报》2024年第6期197-206,共10页Journal of Mechanical Engineering

基　　金：国家自然科学基金资助项目(51875027)。

摘　　要：回弹是影响冷成形高强钢零件尺寸和形状精度的关键因素,而高强钢回弹预测精度取决于材料模型的准确性,研究材料模型对回弹预测精度的影响规律具有重要意义。基于两种不同应变量的拉伸-压缩试验及多循环拉伸-压缩试验,确定了DP780双相钢Yoshida-Uemori(Y-U)随动硬化模型参数。采用LS-DYNA有限元仿真软件分析了不同硬化模型和屈服准则对U弯回弹预测的影响规律,并与回弹试验进行对比。结果表明,通过不同拉伸-压缩试验策略获得的Y-U模型参数存在较大差异,采用多循环拉伸-压缩试验获得的Y-U模型具有更高预测精度,U弯回弹误差可控制在5%以内。随预应变增加,DP780双相钢的弹性模量先急剧降低后逐渐趋于平缓,考虑弹性模量衰减的Y-U模型可提高U弯回弹的预测精度。相比Swift各向同性硬化模型,Y-U随动硬化模型结合Hill48屈服准则可得到更高的回弹预测精度。屈服准则对DP780双相钢回弹的预测有一定影响,但其对回弹精度的影响程度显著低于硬化模型。研究结果对先进高强钢材料模型的选择和回弹预测精度的提升提供了理论依据。Springback is a key factor affecting the dimensional and shape accuracy of cold-formed high-strength steel parts,and the accuracy of high-strength steel springback prediction depends on the accurate material model,it is important to study the influence of the material model on springback prediction accuracy.Based on tension-compression tests with two different strain levels and multi-cycle tension-compression tests,the parameters of the DP780 dual-phase steel Yoshida-Uemori(Y-U)kinematic hardening model were determined.The influence of different hardening models and yield criteria on the U-bending springback prediction was analyzed by LS-DYNA finite element simulation software,and compared with the springback tests.The results show that the Y-U model parameters obtained by different tensile-compression test strategies have great differences,and the Y-U model obtained by the multi-cycle tensile-compression tests has higher prediction accuracy and the U-bending springback error can be controlled within 5%.With the increase of pre-strain,the elastic modulus of DP780 dual-phase steel decreases sharply and gradually becomes flat.The Y-U model considering elastic modulus degradation can improve the prediction accuracy of U-bending springback.Compared with the Swift isotropic hardening model,the Y-U kinematic hardening model combined with the Hill48 yield criterion can obtain higher springback prediction accuracy.The yield criterion has a certain influence on the springback prediction of DP780 dual-phase steel,but its influence on the springback accuracy is significantly lower than that of the hardening model.The research results provide a theoretical basis for the selection of advanced high-strength steel material models and the improvement of springback prediction accuracy.

关 键 词：双相钢 Y-U模型 屈服准则 弹性模量 回弹预测 

分 类 号：TB125[理学—工程力学]