Why is 304 316L stainless steel magnetic? How to demagnetize

304 316L stainless steel is magnetic due to its composition. To demagnetize it, you can use methods such as heating above the Curie temperature, applying an alternating magnetic field, or using a demagnetizing coil.

Martensitic|304 Stainless Steel|Magnetic|316l Stainless Steel|Ferrite

Usually, austenitic 304 material is non-magnetic or weakly magnetic. However, fluctuations in chemical composition or processing state during smelting may cause it to exhibit magnetic properties. This should not be considered as counterfeit or substandard.

Austenite is non-magnetic or weakly magnetic, and martensite or ferrite is magnetic, due to the smelting of compositional segregation or improper heat treatment, will cause austenitic 304 stainless steel in a small amount of martensite or ferrite organization. In this way, 304 stainless steel will have a weak magnetism.

In addition, 304 stainless steel after cold working, the organizational structure will also be transformed to martensite, the greater the degree of cold working deformation, the more martensite transformation, the greater the magnetic properties of steel. As a batch number of steel strip, the production of Φ76 pipe, no obvious magnetic sensation, the production of Φ9.5 pipe. Because of the deformation of bending larger magnetic sense will be obvious, the production of square rectangular pipe because the deformation is larger than the round pipe, especially the corner part, the deformation is more intense magnetic more obvious.

To completely eliminate the magnetic properties of 304 steel caused by the above reasons, through high-temperature solution treatment to restore stable austenitic organization, thereby eliminating the magnetic properties.

The magnetic properties of 304 stainless steel are always shown as weak magnetism, unlike other stainless steel materials such as 430 and carbon steel, which exhibit different levels of magnetism.