冲裁过程分为弹性变形、塑性变形和断裂三个阶段。当凸模接触板料后,对板料施加压力使之产生弹性压缩和弯曲变形;凸模继续对板料施加压力,刃口切入板料内并把一部分金属材料挤入凹模型腔,刃口区的金属产生塑性剪切变形,同时还伴有金属纤维的弯曲和拉伸变形。随着塑性变形的进行刃口附近的材料内的应力不断增大并产生应力 Blanking process is divided into elastic deformation, plastic deformation and fracture of the three stages. When the punch contacts the sheet, applying pressure on the sheet to cause elastic compression and bending deformation; the punch continues to exert pressure on the sheet, the cutting edge cuts into the sheet and squeezes a part of the metal material into the cavity of the concave mold, Area of ​​the metal plastic shear deformation, along with the metal fiber bending and tensile deformation. As the plastic deformation progresses, the stress in the material near the edge increases and stresses