Is the magnetic 304 stainless steel pipe fake | stainless steel pipe knowledge

Are magnetic 304 stainless steel pipes fake? 2016-11-12 In life, people always use magnets to verify the quality and authenticity of stainless steel pipes. They think that if they are magnetic, they are fake or not good. Magnetism is good, real stainless steel tubes. In fact, this judgment method or basis is incorrect. There are many types of stainless steel, and the classification methods are also different, but according to the organizational structure, it can be divided into several categories: 1. Austenite type: such as 304, 321, 316, 310, etc.; 2. Martensite or ferrite type: such as 430, 420, 410, etc. The austenite type is non-magnetic or weakly magnetic, and martensite or ferrite is magnetic. Most of the stainless steel pipes commonly used for decoration are austenitic 304 stainless steel. Like 304 stainless steel pipes, they are generally non-magnetic or weakly magnetic, but they will become magnetic during smelting or processing. That is because the composition segregation or improper heat treatment during smelting will cause a small amount of martensite or ferrite in the austenitic 304 stainless steel tube. In this way, the 304 stainless steel tube will have weak magnetism. In addition, the structure of 304 stainless steel pipe will be transformed into martensitic stainless steel after cold working. The greater the degree of cold working deformation, the more martensite is transformed and the greater the magnetic properties of the steel. For example, using the same batch of steel strips to produce large tubes such as 114 tubes, the magnetism is not obvious, but when producing small tubes like 19 and 22 tubes, the magnetism will be larger. When producing square and rectangular tubes, the deformation is larger than that of round tubes, especially In the corner part, the deformation is more intense and the magnetism is more obvious. Therefore, the authenticity of stainless steel cannot be judged by a magnet alone, and whether it is magnetic is not the basis for judging the quality of stainless steel. 304 stainless steel pipe is non-magnetic or weakly magnetic. Stainless steel has long-term supply of 304 stainless steel pipes for refining furnaces, which are solid and thick, and worry-free after sales!