冲裁间隙对多层薄铜板成形的影响

以单层0.3 mm厚的薄铜板叠6层进行冲裁,研究冲裁间隙对多层薄铜板成形的影响。对多层薄铜板在冲裁成形中的受力与应力状态进行分析,利用ABAQUS软件对多层薄铜板在不同冲裁间隙下的冲裁质量进行有限元仿真。研究表明:冲裁初期最大等效应力出现在凸凹模刃口处,导致最上层与最下层薄铜板先行断裂,中间层薄铜板受相邻层挤压,最大等效应力出现在软质凸凹模刃口处,最后出现在中间层薄铜板缩紧截面内;随着冲裁间隙的增加,各层薄铜板拉伸变形明显,导致冲孔直径增大、毛刺高度增加。前3层薄铜板的冲孔直径变化较为稳定,与凸模直径接近;后3层薄铜板的冲孔直径变化幅度较大,与各自凹模直径接近。最后,通过试验验证,冲裁精度符合国标要求,在实际生产过程中选择合理的、尽可能小的冲裁间隙能提高冲裁件的冲裁质量。

Influence of blanking clearance on forming of multi-layer thin copper plate

A six-layer thin copper plate with single layer thickness of 0.3 mm was blanked,and the influence of blanking clearance on the forming of multi-layer thin copper plate was studied.Then,the forces and stress conditions in the blanking process of multi-layer thin copper plate were analyzed,and the blanking quality of multi-layer thin copper plate under different blanking clearances was simulated by software ABAQUS.The research shows that the maximum equivalent stress at the beginning of blanking occurs at the edge of punch and die to cause the top and bottom thin copper plates to fracture first,and the middle thin copper plate is squeezed by the adjacent layer resulting in the maximum equivalent stress at the soft edge of punch and die.Finally,it appears in the contracted section of the middle thin copper plate.With the increasing of the blanking clearance,the tensile deformation of each thin copper plate is obvious,which leads to increase the punching diameter and the burr height.However,the change of punching diameter at the first three layers of thin copper plate is relatively stable,which is close to the size of the punch,and the change of punching diameter at the last three layers of thin copper plate is relatively large,which is close to the size of the respective die.In the end,through test verification,the blanking accuracy meets the requirements of national standards.In the actual production process,selecting a reasonable and as small blanking clearance as possible can improve the blanking quality of blanking part.