The working principle of Chengdu stress relief annealing is introduced
In the process of pressure processing, casting, welding, heat treatment, cutting and other processes, the products may produce internal stress. In most cases, a part of residual stress will remain in the metal after the process. The residual stress can lead to the fracture, deformation or size change of the workpiece. The residual stress can also improve the chemical activity of the metal, which is especially easy to cause intergranular corrosion cracking under the action of residual tensile stress. Therefore, the residual stress will affect the material performance or lead to premature failure of the workpiece.

In the process of stress relief annealing, the residual stress of metal can be relaxed by local plastic deformation (when the stress exceeds the yield strength of the material at the temperature) or local relaxation (when the stress is less than the yield strength of the material at the temperature) under the action of a certain temperature. During stress relief annealing, the workpiece is generally slowly heated to a lower temperature (500-550 ℃ for gray cast iron, 500-650 ℃ for steel, and below the recrystallization starting temperature for non-ferrous alloy stamping parts). After a period of time, the workpiece is slowly cooled to prevent new residual stress.
Stress relief annealing can not completely eliminate the residual stress in the workpiece, but only most of it. In order to eliminate the residual stress completely, the workpiece needs to be heated to a higher temperature. Under such conditions, other structural changes may occur, which may endanger the performance of the material.
Through the above introduction, I hope to help you know more about Chengdu stress relief annealing information.