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.

1.304 stainless steel. It is one of the most widely used austenitic stainless steels with a large amount of applications. It is suitable for manufacturing deep drawing formed parts, acid transmission pipes, vessels, structural parts, various instrument bodies, etc., as well as non-magnetic and low-t

The content of alloying elements. Generally speaking, steel with a chromium content of 10.5% is not easy to rust. The higher the content of chromium and nickel, the better the corrosion resistance. For example, the content of nickel in 304 material is 8-10%, and the content of chromium is 18-20%. In general, such stainless steel will not rust.

Stainless steel refers to the steel resistant to weak corrosive media such as air, steam and water and chemical corrosive media such as acid, alkali and salt, also known as stainless and acid resistant steel. The corrosion resistance of stainless steel depends on the alloy elements contained in the steel.