After profile stretching, residual stress is usually generated. Residual stress refers to the stress remaining in the material due to various reasons during the shape change of the material. During the stretching process, the material is subjected to stretching and bending, which causes stress to be generated inside the material. When the processing is completed, these stresses do not completely disappear, but remain in the material in the form of residual stress.

The existence of residual stress may affect the performance of the material. For example, residual stress may cause the material to warp or distort, or even crack. In addition, residual stress may also affect the strength, fatigue life and other properties of the material. Therefore, for the residual stress after profile stretching, we need to take appropriate measures to release it.

Here are some common methods to release residual stress:

1. Heat treatment: Heat treatment is a commonly used method to release residual stress. By heating and insulating the material, the stress inside the material can be released. Specifically, heat treatment can be achieved through annealing, normalizing, quenching, etc. Different materials and processing requirements may require different heat treatment processes.

2. Mechanical machining: Mechanical machining is also an effective method to release residual stress. By machining, grinding, polishing, etc., the residual stress on the material surface can be eliminated. In addition, mechanical machining can also improve the surface quality and dimensional accuracy of the material.

3. Vibration aging: Vibration aging is a method that uses vibration energy to release residual stress. By applying vibration of a certain frequency and amplitude to the material, the stress inside the material can be released. Vibration aging is usually suitable for large structural components and complex-shaped parts.

4. Shot peening: Shot peening is a method that impacts the material surface with high-speed flowing shot particles to release residual stress. Shot peening can improve the surface hardness and wear resistance of the material, and at the same time, it can also eliminate the residual stress on the material surface.

5. Ultrasonic treatment: Ultrasonic treatment is a method that uses high-frequency vibration energy to release residual stress. By applying ultrasonic vibration to the material, the stress inside the material can be released. Ultrasonic treatment is usually suitable for small parts and precision instruments.

6. Chemical treatment: Chemical treatment is a method that uses chemical reagents to release residual stress. By acid washing, alkali washing, electrochemical treatment, etc., the residual stress on the material surface can be eliminated. Chemical treatment is usually suitable for metal materials and alloy materials.

In short, residual stress will be generated after profile stretching, and we need to choose the appropriate method to release residual stress according to the specific material and processing requirements. By taking appropriate measures, the residual stress can be effectively released, thereby improving the performance and service life of the material.