Why do metal stamped parts crack?

1. Local tensile stress is too high.
During the processing process, due to excessive local tensile stress, metal stamping parts are subjected to internal stresses, external forces, etc., resulting in local large convex deformation and cracking.
2. The molding process parameters are not implemented on site.
When molding a part, the process requires that the die, press rod, and two parts fit tightly together. As the machine guide slides downward, the sheet material is forced to plastically deform to achieve forming. The technician did not specify according to the process. At this stage, the machine pressure needs to be adjusted in time, and the operation will be unstable, resulting in the stamped parts cracking.
3. Structural defects of the flanging mold.
The mold is a regular single cavity double cavity left/right piece. Because this process includes not only flanging, but also molding. In addition, the parts are particularly complex and the bending surface is narrow. Molding requires pressing into a concave shape. the core must match the molded surface, etc., resulting in the structural conditions of the mold being that the molding stroke is large, the pressing area is small, and cracking occurs.
4. The characteristics of the stamping oil do not meet the technological requirements.
Stamping oil plays a role in insulating the mold and workpiece during the stamping process. However, the use of non-special oils such as rapeseed oil, machine oil and recycled oil will cause scratches on the workpiece due to the instantaneous rupture of the oil film during the stamping process due to poor quality work., burrs and burrs. In severe cases, problems such as cracking of the workpiece and damage to the mold may occur.