Duplex stainless steel has both ferritic and austenitic structures. That’s why that duplex stainless steel has both the performance advantages of ferritic stainless steel and austenitic stainless steel. Duplex stainless steel pipe has the following performance characteristics:
Good mechanical properties
Compared with single-phase ferritic stainless steel and single-phase austenitic stainless steel, duplex stainless steel has higher strength and hardness, and its plasticity and toughness are in between. The yield strength of the second generation duplex steel can be as high as twice that of TYPE 18-8 austenitic stainless steel.
Better corrosion resistance
Under low stress conditions, general austenitic stainless steels are susceptible to stress corrosion and fracture in a neutral chloride solution at a temperature above 60℃, while duplex stainless steels have good chloride stress corrosion resistance and are suitable for use It is used to manufacture industrial equipment serving in chloride and other media.
Duplex stainless steel has good pitting corrosion resistance: when it has the same pitting resistance equivalent value, the critical pitting potential of duplex stainless steel and austenitic stainless steel are similar. Duplex stainless steel containing 25% Cr, especially nitrogen-containing high chromium duplex stainless steel, has pitting corrosion and crevice corrosion resistance that exceeds austenitic stainless steel. Under certain corrosive medium conditions, it is suitable for corrosive fluid piping systems.
Good processing performance advantages
Compared with austenitic stainless steel, duplex stainless steel has a wider hot working temperature range and lower resistance. Therefore, duplex stainless steel can be directly rolled and billeted without forging, and used for duplex stainless steel welded pipes. Duplex stainless steel has a greater work hardening effect during cold working.
Other properties: Compared with austenitic stainless steel pipes, duplex stainless steel pipes have greater thermal conductivity and smaller linear expansion coefficients.
Posted by stainless steel pipe fittings supplier, KAYSUNS.
