超高强钢前纵梁零件冲压开裂分析与处理

Analysis and Treatment of Stamping Cracking of Front Longitudinal of Ultra-High Strength Steel

目的解决780 MPa级别超强度钢板冷冲压生产汽车前纵梁时发生的冲压开裂问题。方法通过网格应变分析技术和仿真分析,研究该零件冲压开裂的原因,分析引起开裂的因素,基于CAE模型系统,研究压边力、模具间隙、坯料尺寸、材料性能对开裂的影响规律。结果降低压边力和增加模具间隙均能减轻开裂,但是无法消除冲压开裂;坯料尺寸缩小可以消除冲压开裂,但是优化坯料尺寸需要改变模具上的坯料定位器,同时增大起皱风险;通过提升材料性能可以消除开裂。结论考虑最终各方案成本,选择性能优异的材料进行生产,将冲压开裂率降低至0.6%,满足了冲压要求。

The paper aims to solve stamping cracking of front longitudinal made of 780 MPa grade super-high strength steel plate. The reasons of stamping cracking were analyzed by grid strain analysis and simulation analysis. Based on the CAE model system, influences of blank holder force, mold gap, blank size and material properties on cracking were studied. The results show that reducing the blank holder force and increasing the mold gaps could reduce the cracking, but cannot eliminate the punching cracking; reduction of blank size could eliminate the punching cracking, but optimization of blank size needed to change the blank locator on mold; while the risk of wrinkling was increased; lifting material properties could eliminate cracking. Finally, consideration of cost of each program to select the excellent performance of the material for production reduces the stamping cracking rate to 0.6%, which meets the stamping requirements.