Ys, which is popular on the internet, means yield strength, which is the yield limit of metal materials when they yield, that is, the stress to resist micro-plastic deformation. For metal materials with no obvious yield phenomenon, the yield limit is defined as the stress value that produces 0.2% residual deformation, which is called conditional yield limit or yield strength.

brief introduction

The external force greater than the yield strength will make the parts permanently invalid and irreversible. For example, the yield limit of low carbon steel is 207MPa. When the external force is greater than this limit, the parts will be permanently deformed, and when it is less than this, the parts will return to their original appearance.

Yield strength is not only of direct use significance, but also a rough measure of some mechanical behaviors and technological properties of materials in engineering. For example, when the yield strength of materials increases, they are sensitive to stress corrosion and hydrogen embrittlement. The material has low yield strength and good cold formability and weldability. Therefore, yield strength is an indispensable and important index in material properties.