Hardness is a kind of mechanical property index reflecting the softness and hardness of materials. Hardness measurement is widely used in mechanical property measurement tests. There are two main methods, one is the indentation method, which is usually used for the hardness measurement of stainless steel tubes. One is the characterization method. The press-in method is further divided into a dynamic load indentation method and a static load indentation method, and the dynamic load indentation method includes ultrasonic hardness, Shore hardness and hammering Brinell hardness; and static load indentation method includes Rockwell hardness and Brinell. Hardness, Vickers hardness and microhardness. The scoring method includes the sickle method. Mohs hardness method. The calculation formula of Rockwell hardness is the value of k in the formula HR=(kh)/0.002, the indenter is 0.26 when quenching the steel ball, and 0.2 when the indenter is diamond, h is the indenter pressed under the action of the load. The actual depth.