Classification of Stainless Steel Stainless steel is usually divided into:

1. Ferritic stainless steel. Contains 12% to 30% chromium. Its corrosion resistance, toughness and weldability increase with the increase of chromium content, and its chloride stress corrosion resistance is better than other types of stainless steel.

2. Austenitic stainless steel. It contains more than 18% chromium, and also contains about 8% nickel and a small amount of molybdenum, titanium, nitrogen and other elements. It has good comprehensive performance and can withstand corrosion from various media.

3. Austenitic-ferritic duplex stainless steel. It has the advantages of both austenitic and ferritic stainless steel and has superplasticity.

4. Martensitic stainless steel. High strength, but poor plasticity and weldability.