What is a duplex stainless steel? It and contain a small amount of ferrite austenite stainless steel have what differentiation?
Austenite plus ferrite in the duplex stainless steel is stainless steel there are both austenite and ferrite structure of steel grade, and the two phase organization should exist independently, content are large, generally considered the least phase content should be greater than 15%. And application in practical engineering of austenite plus ferrite duplex stainless steel (used to call a + 7 duplex stainless steel and duplex stainless steel) much for austenitic base and contains not less than 30 write of ferrite, the most common is two phase the duplex stainless steel accounts for about 50. Duplex Stainless Steel (DSS in English (Duplex Stainless Steel).
Because of the. A + Y duplex structure, duplex stainless steel and austenitic stainless steel and ferritic stainless steel. Compared with the ferritic stainless steel, duplex stainless steel is a + Y high toughness, low brittle transition temperature, the intergranular corrosion resistance and welding performance were significantly improved; At the same time retain the some characteristics of ferritic stainless steel, such as 475 ℃ brittleness, high thermal conductivity, small linear expansion coefficient, superplasticity, magnetic, etc. A + 7 compared with austenitic stainless steel duplex stainless steel of high strength, especially the yield strength significantly increased, and the resistance to intergranular corrosion, stress corrosion and corrosion fatigue performance has improved.
