用成形凹模的拉延过程是一般拉延过程的一种推广。其主要优点是:大幅度降低变形刀,提高拉延比,不需要压边圈。基于近似上限法,作者提出一种新的数值计算方法,以设计凹模轮廓。利用本文所提出的方法,还可以予测压力行程曲线,杯壁厚度变化情况以及行程内杯壁中最大拉伸应力。研究结果表明,凹模轮廓与应变硬化、摩擦系数以及杯壁厚度变化几乎无关。应变硬化对平均单位压力或变形力有很大的影响。 The process of drawing a die is a general extension of the drawing process. Its main advantages are: greatly reduce the deformation knife, improve the draw ratio, without blank holder. Based on the approximate upper bound method, the authors propose a new numerical method to design the die profile. Using the method proposed in this paper, the pressure stroke curve, the variation of cup wall thickness and the maximum tensile stress in cup wall can be estimated. The results show that the die profile has little to do with strain hardening, friction coefficient and cup thickness. Strain hardening has a large effect on the average unit pressure or deformation force.