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Ferritic stainless steel refers to a kind of stainless steel with 11% ~ 30% Cr, which has square crystal structure with lifting core and ferrite structure under service condition. According to the difference of chromium content in steel, ferritic stainless steel can be roughly divided into 11% ~ 15% Cr, 16% ~ 20% Cr, 21% ~ 30% CR, In the third category, the chromium content of super ferritic stainless steel is generally 25% - 30%, belonging to high chromium ferritic stainless steel.

Ferritic stainless steel refers to all kinds of ferritic stainless steel with low carbon, nitrogen and ultra-low carbon and nitrogen produced by modern stainless steel production process, especially by using AOD, VOD and vacuum furnace refining technology. At present, there are mainly high-purity ferritic stainless steel; super ferritic stainless steel; low carbon, nitrogen, ultra-low carbon, nitrogen medium chromium ferrite stainless steel and low chromium ferrite stainless steel.