T2铜板冲裁间隙对冲裁力及断面质量的影响

The effect of punching clearance on punching force and quality of cross section for T2 Copper

为提高冲裁件的断面质量和冲裁效率,实现对冲裁间隙的合理优化,现提出了一种新的板料冲裁试验构想:采用广泛应用于变压器等领域板厚为6 mm且相同规格的T2紫铜作为试验材料,通过更换凸模来改变冲裁间隙,完成在不同冲裁间隙条件下对板料的冲裁试验,采集并分析冲裁力随冲裁行程的变化曲线;同时测量光亮带的宽度和最大冲裁力位置,并拟合冲裁力、光亮带宽度等与冲裁间隙之间的曲线.试验表明:冲裁力在塑性变形阶段增大幅度先快后慢,而在此阶段的初期冲裁间隙对冲裁力几乎无影响,但随着冲裁的深入,冲裁间隙越大,冲裁力则越小,当进入断裂带后冲裁力急速下降;对比在相同冲裁间隙条件下冲裁力随冲裁行程的变化曲线和断面质量,可获得冲裁件断面光亮带会随着冲裁力达到最大值时而结束.研究表明,当冲裁间隙为16.67%左右时,光亮带宽度较大且冲裁力较小.

In order to improve the efficiency and cross-sectional quality of punching parts,and achieve a reasonable optimization of punching clearance,now a new sheet metal punching test idea was proposed： the T2 copper with about 6 mm thickness and the same specifications could be used as the test material,which is widely used in transformers and other,by replacing the top die to change the punching clearance,and the punching test for sheet metal under different conditions of punching clearance could be carried out,so punching pressure with the change of the cutting stroke could be collected and analyzed; Measure burnish sectional width and position of maximum punching force simultaneously,and fit curve of both punching force and bright sectional width with the punching clearance. The experimental results show that in stage of plastic deformation the punching force increases rapidly at first then slow down,but in early period of the stage the punching clearance has no effect on the punching force,then with the depth of punching,the greater punching clearance,the smaller punching force,when entering the fault zone the punching force decline dramatically; Compare with section quality and the punching force along with the change of punching trip under the same conditions,that bright cross section will end when the punching force reaches a maximum can be obtained. Research shows that when punching clearance is about 16. 77%,the bright sectional width is larger and the punching force is smaller.