薄板类件多点成形过程的数值模拟

以希尔关于弹塑性材料唯一性的充分性条件为理论基础,采用虚功率增率型原理,建立了多点成形的有限元模型,探讨了板材厚度、材质及弹性介质等因素对成形结果的影响,通过数值模拟找出参数合适的弹性介质,并对薄板类件的多点成形过程进行了实验验证.研究表明,通过使用参数合适的弹性介质,可以有效抑制压痕现象的产生,并能保证工件的成形精度;实验验证表明对马鞍形件多点成形过程中压痕现象的模拟是合理的.

Numerical simulation during multi-point forming process of sheet metal

On the theoretical basis of Hill' so-called exclusive sufficiency condition on elastic plastic materials and virtual power principle, a finite element model for multi-point forming is given. The effect during multi-point forming process is discussed by means of numerical simulation, on the aspects of thickness, material of sheet metal and elastic medium. The elastic medium with suitable parameter is found through numerical simulation. The result proves that the application of elastic medium with suitable parameter can restrain impressed mark efficiently and insure the forming precision of the part. Moreover, the experiment on the multi-point die forming of sheet metal by the MPF machine is done to validate the efficiency of the numerical simulation.