Duplex stainless steel plate in specification S31803 (1.4462) and S32205. Duplex stainless steel was developed as a product which could improve upon some of the technical weaknesses of the standard austenitic and ferritic stainless steels that are available in the market. Both have low strength, ferritic steels have poor low temperature toughness, and austenitic steels have a very low resistance to stress corrosion cracking. Duplex stainless has a micro-structure which is split roughly 50:50 between austenite and ferrite and balancing of these phases provides the following benefits:
Higher strength which is around twice that of Type 304 austenitic stainless steel. This leads to reduced plate thicknesses being used in fabrications reducing the weight which is of particular significance in items such as pressure vessels, storage tanks, and structural applications such as bridges.
● Good weld ability in thick plates.
● Good low temperature toughness.
● Resistance to stress corrosion cracking of importance in many applications including hot water tanks, process plant, brewing tanks, and desalination plant.