1, fillet belt. Fillet band, also known as corner collapse, is produced by bending and stretching the surface of the material near the upper die or the lower die but not in contact with the stamping die.

2, bright belt. Bright band is caused by plastic shear deformation when the upper die cuts into the steel plate and the material is squeezed into the lower die. Bright band is the area with the best cross-sectional quality of metal stamping parts, and the Liang Guang is flat and perpendicular to the plane of steel plate. Precision stamping generally pursues light band.

3. Fault zone. The surface of the fault zone is rough, with an inclination of about 5 degrees, which is caused by the crack propagation formed during stamping.

4, burr. The burr is close to the edge of the fracture zone, and the position where the crack occurs is not right against the die edge, but on the side close to the die edge, which will be aggravated when the metal stamping part is pushed out of the die by the lower die.