压边力成形窗口建立方法的研究

Research on establishment method of BHF forming window

在分析板料成形中起皱和破裂判据的基础上,针对变压边力成形提出了建立压边力成形窗口的方法。为了获得区域较大的成形窗口,该方法设计了两种极端的压边力加载模式,即Z形和反Z形加载模式,并通过数值模拟获得了某筒形件成形窗口的上下边界。研究结果表明,不同的极端压边力加载模式可得到不同的成形窗口,出于安全和可靠性考虑,可在多个成形窗口的交集部分选择压边力加载曲线。

Based on the judgments of critical wrinkling and fracturing condition analysis, a method was proposed to build the forming window aiming at the variable blank holder force （BHF） forming. In order to obtain a larger area of forming window, two extreme BHF loading modes were designed, namely the Z and inverse Z loading mode. And then, the boundary of forming window for a cylindrical cup was got by numerical simulation. Research results show that different extreme BHF loading modes lead to the different forming windows. Considering the safety and reliability, BHF loading curve can be chosen among the intersection of multiple forming windows.