Rockwell hardness
Use diamond cone or quenched steel ball indenter to press the indenter into the material surface under the action of test pressure F. After holding for a specified time, remove the main test force and maintain the initial test force. Calculate the hardness value with the residual indentation depth increment. During actual measurement, the Rockwell hardness value can be directly read out through the dial of the testing machine. Indenter: a cone with a cone angle equal to 120 °, or a quenched steel ball with a diameter of D=1.588mm.