Stainless steel has a series of characteristics such as excellent corrosion resistance, formability and toughness in a wide temperature range, so it has been widely used in heavy industry, light industry, daily necessities industry and building decoration industries. Different stainless steel varieties are very important.

In stainless steel, two opposing forces operate simultaneously: ferrite forming elements continue to form ferrite, and austenite forming elements continue to form austenite. The final crystal structure depends on the relative amounts of the two types of additive elements. Chromium is a ferrite forming element, so chromium in the formation of stainless steel crystal structure and the austenite forming element is a competitive relationship. Because iron and chromium are ferritic forming elements, the 400 series stainless steels are fully ferritic stainless steels with magnetic properties. In the process of adding the austenite forming element nickel to fe-Cr stainless steel, with the increase of nickel composition, the formation of austenite will gradually increase, until all the ferrite structure is transformed into austenite structure, thus forming 300 series stainless steel.

300 series stainless steel is an alloy material containing iron, carbon, nickel and chromium. It is a non-magnetic stainless steel material with better malleability than 400 series stainless steel. Due to the austenitic structure of 300 series stainless steel, it has strong corrosion resistance in many environments, excellent resistance to fracture caused by corrosion caused by metal overstress, and its material properties are not affected by thermal treatment.