How much chromium is called stainless steel?
In practical application, the steel which is often corroded by weak corrosive medium is called stainless steel, and the steel which is resistant to chemical medium is called acid resisting steel. Because of the difference in chemical composition between the two, the former is not necessarily resistant to chemical medium corrosion, while the latter is generally stainless. The corrosion resistance of stainless steel depends on the alloying elements contained in the steel.
Stainless steel (Stainless, Steel) refers to air, steam, water and other weak corrosive medium and acid, alkali, salt and other chemical corrosive medium corrosion of steel, also known as stainless acid resistant steel.
1 ferritic stainless steel. Chromium 12% ~ 30%. Its corrosion resistance, toughness and weldability increase with the increase of chromium content, and the resistance to chloride stress corrosion is better than other kinds of stainless steel. 2 austenitic stainless steel. Chromium more than 18%, but also contains about 8% of nickel and a small amount of molybdenum, titanium, nitrogen and other elements. Good comprehensive performance, corrosion resistant variety of media. 3 austenite ferrite duplex stainless steel. It has the advantage of austenite and ferritic stainless steel and has superplasticity. 4 martensitic stainless steel. High strength, but poor plasticity and weldability.
