Factors affecting the yield strength of seamless pipe

Yield strength is an important concept in the field of seamless pipe mechanics. It is the stress value of seamless steel pipe when the ductile material yields. When the seamless steel pipe will deform under the action of force, the deformation at this time can be divided into two ways: plastic deformation and elastic deformation.

1. Plastic deformation will not disappear when the external force disappears, and the seamless steel pipe will undergo permanent deformation.
2. Elastic deformation means that under the condition of external force, when the external force disappears, the deformation will also disappear.

The yield strength is also the stress value of the seamless pipe when it begins to undergo plastic deformation, but because the brittle material does not undergo obvious plastic deformation when it is stretched by an external force, only the ductile material has the yield strength.

Here, the yield strength of seamless pipe we refer to is the yield limit when yielding occurs, and the stress against micro-plastic deformation. When the force is greater than this limit, the part will permanently fail and cannot be recovered.

The external factors affecting the yield strength of seamless pipes are: temperature, strain rate, and stress state. As the temperature decreases and the strain rate increases, the yield strength of the seamless steel pipe also increases, especially when the body-centered cubic metal is sensitive to temperature and strain rate, which will cause low-temperature embrittlement of the steel. The influence on the stress state is also very important. Although the yield strength is an essential index reflecting the intrinsic performance of the manufactured material, the yield strength is different due to different stress states.
Intrinsic factors affecting yield strength are: bond, organization, structure, and atomic nature. If we compare the yield strength of seamless pipe metal with ceramics and polymer materials, we can see from it that the influence of bonding bonds is a fundamental problem.