inpower Dual phase rigid oil-free screw vacuum pump combines the characteristics of austenitic and ferritic stainless steel. Compared with ferritic stainless steel, it has higher plasticity and toughness, no room temperature brittleness, significantly improved intergranular corrosion resistance and welding performance. At the same time, it maintains the 475 ℃ brittleness and high thermal conductivity of ferritic stainless steel, and has characteristics such as superplasticity.
Dual phase steel is a steel composed of martensite, austenite, or bainite and a ferrite matrix. It is obtained by critical zone heat treatment or controlled rolling of low carbon steel or low-alloy high-strength steel.
(1) Molybdenum containing duplex stainless steel exhibits excellent resistance to chloride stress corrosion under low stress. Generally, 18-8 austenitic stainless steel is prone to stress corrosion cracking in neutral chloride solutions above 60 ℃. Heat exchangers, evaporators, and other equipment made with this type of stainless steel in trace chloride and hydrogen sulfide industrial media tend to experience stress corrosion cracking, while duplex stainless steel has good resistance.
(2) Molybdenum containing duplex stainless steel has good resistance to pitting corrosion. Having the same equivalent value of pitting resistance
When PRE=Cr%+3.3Mo%+16N%, the critical pitting corrosion potential of duplex stainless steel is similar to that of austenitic stainless steel. The pitting corrosion resistance of duplex stainless steel and austenitic stainless steel is equivalent to that of AISI 316L. The resistance to pitting and crevice corrosion of high chromium duplex stainless steel containing 25% Cr, especially nitrogen, exceeds that of AISI316L.
