1. Austen body type: such as 304, 321, 316, 310, etc;

　　2. Martensitic or ferritic type: such as 430, 420, 410, etc;

　　Austenite is non-magnetic or weakly magnetic, while martensite or ferrite is magnetic.

　　The stainless steel wire mesh commonly used for decorative tube sheets is mostly made of austenitic 304 material, which is generally non-magnetic or weakly magnetic. However, magnetism may also occur due to fluctuations in chemical composition or different processing conditions caused by smelting. However, this cannot be considered as counterfeit or unqualified. What is the reason for this?

　　As mentioned above, austenite is non-magnetic or weakly magnetic, while martensite or ferrite is magnetic. Due to component segregation or improper heat treatment during smelting, it can cause a small amount of martensite or ferrite structure in austenitic 304 stainless steel wire mesh. In this way, 304 stainless steel wire mesh will have weak magnetism.

　　In addition, after cold processing, the microstructure of 304 stainless steel wire mesh will also transform into martensite. The greater the cold processing deformation, the more martensite transformation, and the greater the magnetic properties of the steel. Like a batch of steel strips, producing a diameter of 76 tubes without obvious magnetic induction, producing a diameter of 9.5 tubes. Due to the large deformation caused by cold bending, the magnetic induction is more pronounced. The production of square rectangular pipes has a greater amount of deformation than circular pipes, especially in the angled part, which causes more intense deformation and more obvious magnetic induction.

　　To completely eliminate the magnetism of 304 steel caused by the above reasons, high-temperature solid solution treatment can be used to restore stable austenite structure, thereby eliminating magnetism.