Defects in Metal Material Forming Processing, Part 11

Defects in metal forming processes can arise due to various factors, including material properties, process parameters, and environmental conditions. Here are some common defects associated with metal forming:

Pockmarks

The rough surface of the product with tiny dot-shaped depressions is called pockmarks.

The pockmarks are distributed locally or continuously in patches. Individual pockmarks are called pits, and severe pockmarks are called pits. The pockmarks caused by coarse grains are commonly known as orange peel.

The main reasons for the pockmarks are: the annealing temperature is too high, the time is too long, the grains are coarse; over-pickling; the processing rate is too small, the surface is not smooth; the surface hardness of the roller is uneven, the wear is serious, the rolling tools are rusted, there are oxide scales or foreign metals.