汽车后挡风玻璃热弯成形及回弹过程研究

Study on the Hot Bend Forming And Springback Process of Automotive Rear Windshield

基于粘弹性材料的有限元理论,应用有限元模拟方法研究了具有深弯复杂曲面特征的汽车后挡风玻璃的热弯成形工艺及回弹问题。使用广义Maxwell模型来描述玻璃在高温下的粘弹性质。利用有限元分析软件,合理简化模型,对采用压模成形工艺的汽车后挡风玻璃的热弯成形和回弹进行了有限元仿真。研究了汽车后挡风玻璃在经过压制、落模、回弹阶段的应力分布和变形情况。针对玻璃的回弹问题,分析了主要工艺参数对玻璃回弹的影响情况及应力与回弹的关系,为提高玻璃型面质量和模具设计精度提供参考。

Bases on the finite element theory of viscoelastic material, the hot bend forming and spring-back mechanism of the automotive rear windshield with deep curved and complex surface characteristics are researched using the finite element simulation method. The generalized Maxwell model is introduced to describe the viscoelastic properties of glass at high temperature. By reasonable simplified model, the hot bend forming and spring-back of the automotive rear windshield are simulated numerically by finite element analysis software. The stress distribution and deformation of rear windshield are analyzed in the stages of press, drop and spring-back. The influence of main process parameters and stress to spring-back of the glass is investigated deeply. The research findings provide valuable reference to the surface quality improving of glass and accuracy designing of the forming mold.