Duplex-stainless steel is a stainless steel with about half of each austenitic and siderite tissue. At low C, Cr was 18%~28% and Ni 3%~10%, and also contains alloy elements such as Mo, Cu, Si, Nb, Ti, N. This kind of steel has both austenite and iron stainless steel characteristics, plasticity, higher toughness, no room temperature fragility compared to iron, intercrystallite corrosion resistance and welding performance are significantly improved, but also maintain the 475℃ fragility of iron stainless steel and high thermal conductivity, and other characteristics of super plasticity. Instamatic corrosion resistance and chloride stress corrosion compared with austenite stainless steel. Duplex-stainless steel has excellent pore corrosion resistance, is a nickel-cut stainless steel.

General Standard and Application of Duplex Stainless Steel Tube
S.N.StandardsApplication 
1ASTM A789Seamless and Welded Ferritic/Austenitic Stainless Steel Pipe for General Service
2ASTM A790Seamless and Welded Ferritic/Austenitic Stainless Steel Pipe
3EN 10216-5Seamless Steel Tubes for Pressure Purposes-Stainless Steel Tube
4EN 10217-7Welded Steel Tubes for Pressure Purposes-Stainless Steel Tube
5EN 10296-2Welded Circular Steel tubes for Mechanical and General Engineering Purposes-Stainless Steel Tube
6EN 10297-2Seamless Circular Steel Tubes for Mechanical and General Engineering Purposes-Stainless Steel Tubes