基于Yoshida_Uemori材料模型的整形工艺超高强钢地板纵梁的回弹分析

Springback analysis on sizing process of longitudinal floor beam for super high strength steel based on Yoshida_Uemori material model

首先通过试验测试的方法测定了QP980超高强钢零件的Yoshida＿Uemori材料模型的各相关参数,并以此作为后续研究的基础。然后以地板纵梁为研究对象,分别完成了仿真过程和实际生产过程的数据分析,通过对比回弹分布,验证了使用Yoshida＿Uemori硬化曲线的材料模型在实际生产过程中的回弹计算准确性。再进一步以仿真数据为基础,分析此类型零件回弹特点产生的原因。最终发现：对于法兰位置有凸台的地板纵梁零件,在中间位置侧壁的主应变方向一致性较好,以平行于法兰方向为主,顶层的主应变达到0.52左右,底层的主应变达到0.3左右,容易通过平行于法兰方向的回弹来释放;而靠近端部的顶层的主应变达到0.4左右,方向一致性较差,从而通过变形释放的趋势较小;以上这些导致零件中部的侧壁角回弹为两端角回弹值的1.5～2. 5倍。

The related parameters of Yoshida-Uemori material model for QP980 super high strength steel part were measured by tests,and taking this as the foundation of follow-up research. Then the data analyses of simulation process and actual production process were completed for longitudinal floor beam. By comparing the springback distribution,the springback calculation accuracy of the material model applying the hardening curve of Yoshida_Uemori in the actual production process was verified,and the causes of this type of springback characteristic were analyzed based on the simulation data. Finally,it is found that the direction similarity of major strain at the central side wall is good and mainly in the direction parallel to the flange for longitudinal floor beam part with bosses at flange locations,and the principal strains at the top and bottom reach about 0. 52 and 0. 3 respectively which are easy to release by the springback parallel to the flange.However,the principal strain near two ends is up to 0. 4,and the direction similarity is worse,thus,the tendency to release through deformation is small. So above all of these cause the angle springback at the central side wall to be 1. 5-2. 5 times that near two ends.