汽车覆盖件成形中拉延筋的设计与数值模拟

Drawbead Design and Simulation of Automobile Panel Forming

汽车覆盖件冲压成形中容易出现未充分变形、起皱、变薄、拉裂等缺陷。为了提高成形质量,通常在模具上设置拉延筋来控制坯料的流动,从而提高成形质量。在有限元模拟仿真中,为了简化网格划分,减少计算时间,通常采用等效拉延筋,因此给出了等效拉延筋的拉延阻力和最小压边力计算模型。使用有限元分析软件Autoform模拟了某汽车覆盖件的拉延成形,并通过改变拉延筋的几何尺寸,改善了拉延成形工艺,缩短了模具的开发周期,降低了设计成本。

The defects of automobile panel forming are easily generated, such as compress, wrinkling, crock and so on. In order to improve the quality of forming, the drawbeads usually adjust to the flow of the mental. In the finite element simulation, equivalent drawbeads are used in order to simplify the meshing and reduce the computation time. Therefore, the basic formula of restraining force and hold down farce calculation on rounded drawbead is given. By using element simulation software A utofarm, the forming process of automobile panel is simulated. By changing the geometry of drawbeads, the drawing quality is improved and the development cycle of the mold is shorten.