LAUSR

Abstract Shearing is a cutting method with high productivity. The cut surface consists of a shear droop, a burnished surface, a fractured surface and burr. Press shaving removes the shear droop and fractured surface on the cut surface obtained by shearing to increase the length of the burnished surface. In press shaving, the trimming allowance is set to a small value. The amount of chips obtained by press shaving is very small. The occurrence of small chips is a problem for press working. Therefore, it is desirable that a large burnished surface is obtained without the occurrence of small chips. When piercing with a small trimming allowance was previously carried out after half punching, a chip was connected to the sheet material under the punch. However, the length of the burnished surface was decreased. In this study, piercing using a protrusion punch after half punching was carried out to increase the length of the burnished surface. The effect of the use of a protrusion punch on the length of the burnished surface and the shape of the chip was investigated.