In the process of third-party inspection, it is common to use small magnets to test the magnetic property of stainless steel and incorrectly believe that non-magnetic or weakly magnetic stainless steel is the genuine one. However, this method is one-sided and incorrect.

  Stainless steel is a widely used metal material, which can be divided into different types according to its internal structure, such as austenite, martensite, and ferrite. Austenitic stainless steels, such as 201, 304, 316, are usually non-magnetic or weakly magnetic, while martensitic or ferritic stainless steels, such as 410, 420, 430, are magnetic. During the process of smelting, the chemical composition or heat treatment may vary, resulting in austenitic stainless steel containing a small amount of martensite or ferrite, leading to its weak magnetic property. In addition, cold working may also cause the structure of austenitic stainless steel to transform to martensite, thus increasing its magnetic property.

  Therefore, it is one-sided to distinguish the authenticity of stainless steel only by its magnetic property. To accurately identify the authenticity of stainless steel, we need to consider its chemical composition, internal structure, processing technology and other factors. Only by comprehensively understanding the characteristics of stainless steel and conducting a comprehensive analysis can we make an accurate judgment.