Duplex stainless steel: A stainless steel that combines the advantages of austenitic and ferrite
Duplex steel is twice as large as ordinary austenitic stainless steel. It is not only a material for duplex steel pipes, but also duplex fittings.
Compared with ferritic stainless steel, duplex stainless steel has high toughness, low brittle transition temperature, and excellent resistance to intergranular corrosion and weldability. At the same time, it retains some characteristics of ferritic stainless steel, such as 475 °C brittleness and heat. High conductivity, small linear expansion coefficient, superplasticity and magnetic properties.
Compared with austenitic stainless steel, the strength of duplex stainless steel is higher, especially the yield strength is significantly improved, and the properties such as pitting corrosion resistance, stress corrosion resistance and corrosion fatigue resistance are also significantly improved.
Since the birth of dual-phase steel in the United States in the 1940s, it has grown to the third generation. Its main feature is that the yield strength can reach 400 to 550 MPa, which is twice that of ordinary stainless steel, so it can save materials and reduce equipment manufacturing costs.
In terms of corrosion resistance, especially in the medium environment (such as seawater, high chloride ion content), the resistance of pitting, crevice corrosion, stress corrosion and corrosion fatigue of duplex stainless steel is better than ordinary austenite stainless steel.
The duplex 2205 pipe from stainless steel fittings supplier kaysuns has the characteristics of austenitic and ferritic stainless steel. Compared with ferrite, it has higher plasticity, toughness, no room temperature brittleness, resistance to intergranular corrosion and weldability, and also Maintain 475 ° C brittleness and high thermal conductivity of ferritic stainless steel, with super plasticity. Compared with austenitic stainless steel, it has high strength and resistance to intergranular corrosion and chloride stress corrosion.
Duplex stainless steel has excellent pitting resistance. It is also a nickel-nickel stainless steel duplex stainless steel with austenitic + ferrite dual phase structure, and the content of the two phases is basically the same, so it has austenitic stainless steel. And the characteristics of ferritic stainless steel.