冲压成形中凹模入口角曲线优化

冲压成形时,凹模入口角的形状对模具与工件之间的摩擦、冲压件表面质量以及模具使用寿命均有着重要的影响。为能获得最优的凹模入口角,提出了采用三次样条曲线作为凹模入口角曲线的新工艺方法。以板料与凹模入口角处的摩擦力做功为研究对象,基于响应面和试验设计方法,在满足成形质量前提下,优化凹模入口角曲线。结果表明:采用优化后的三次样条曲线进行凹模入口角设计，可以减小凹模入口角处的摩擦力做功，且摩擦力做功分布较均匀；可延长模具使用寿命,并可以提高工件表面质量。

Optimization of Draw-die Entrance Curve in Sheet Metal Stamping

During the sheet metal stamping, the shape of the draw-die entrance has an important influence on the friction between the sheet metal and die surfaces, the quality of the sheet metal surface and the life of tool. To get an optimal the draw-die entrance curves, a new method of using cubic spline curve as the draw-die profile was adopted. This paper investigated the effects of draw-die entrance curves on the sheet metal tool wear distribution over the entrance of the die. With the forming quality requirements, searching for an optimal die profile was based upon response surface methodology and design of experiments. The results demonstrate that the tool wear is reduced significantly and well distributed over the entrance of the draw-die using the optimized cubic spline curve profile. As a result, the occurrence of surface defects is reduced, the quality of the sheet metal surface is increased, and the life of the tool can be extended.