Defects in Metal Material Forming Processing, Part 10

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:

Wrinkling

The surface of the product is uneven, with slight corrugated depressions and convexities, which is called wrinkling.

Wrinkles are generally consistent with the rolling direction or distributed obliquely, with single or multiple ridges, smooth to the touch, and large in area.

The main reasons for wrinkling are: uneven rolling, or poor straightness of unidirectional bending; uneven tension (uneven tension roller or tension sleeve); poor plasticity of pipe blanks and severe eccentricity; uneven deformation of thick-walled pipes, or excessive deformation; poor roller adjustment and other process defects.