Many people often use magnets to adsorb stainless steel round steel to verify its pros and cons and its authenticity. If it is not attracted or magnetic, it is considered to be good and genuine; if it is magnetic,forged round bar it is considered to be a counterfeit. In fact,forged round bar this is an extremely one-sided and impractical method of identifying errors. The stainless steel round steel usually used as decorative tube sheet is mostly austenitic 304 material. Generally speaking,forged round bar it is non-magnetic or weak magnetic. However,forged round bar due to chemical composition fluctuations or different processing conditions caused by smelting, magnetism may also appear, but this cannot Think that the bridge crane is counterfeit or unqualified. What is the reason?

As mentioned above, austenite is non-magnetic or weakly magnetic,forged round bar while martensite or ferrite is magnetic. Due to component segregation or improper heat treatment during smelting,forged round bar a small amount of martensite or ferrite in austenitic 304 stainless steel will be caused. Body tissue. In this way, 304 stainless steel round steel will have weak magnetism. In addition, after 304 stainless steel round steel is cold worked,forged round bar the structure will also be transformed into martensite. The greater the degree of cold working deformation, the greater the transformation of martensite and the greater the magnetic properties of the steel. Like a batch of steel belts, Φ76 tubes are produced without obvious magnetic induction,forged round bar and Φ9.5 tubes are produced. Because the bending deformation is larger, the magnetic induction is more obvious,forged round bar and the deformation of the square rectangular tube is larger than that of the round tube, especially the corner part,forged round bar the deformation is more intense and the magnetism is more obvious.

In order to completely eliminate the magnetic properties of 304 stainless steel round steel caused by the above reasons,forged round bar the austenite structure can be restored and stabilized by high-temperature solution treatment,forged round bar thereby eliminating the magnetic properties. In particular, the magnetism of 304 stainless steel round steel caused by the above reasons is not at the same level as that of other stainless steel round steel, such as 430 and carbon steel. That is to say,forged round bar the magnetism of 304 stainless steel round steel is always displayed. Is weakly magnetic. This tells us that if the stainless steel round steel is weakly magnetic or not magnetic at all, it should be judged as 304 or 316 material;forged round bar if it is the same as carbon steel, it shows strong magnetism, because it is judged as not 304 material.