Influence of manganese on microstructure and mechanical properties of duplex stainless steel with low nickel content
The effects of Mn content and solution treatment temperature on the microstructural evolution and mechanical properties of 17Cr-2Ni-0.2N-xMn duplex stainless steel were investigated by utilizing microstructural characterization and mechanical testing methods.The results indicate that while Mn,among the austenite-forming elements(Mn,Ni,N),exerts the least influence on the austenite-ferrite phase equilibrium temperature,it significantly enhances austenite stability.An increase in Mn content decreases the amount of quenched martensite and suppresses deformation-induced martensitic transformation,thereby improving the steel's ductility and toughness.Notably,with an Mn mass fraction of 3％,the steel attains a desirable balance of mechanical properties,including 35.5％elongation,944 MPa tensile strength,and 139J impact energy at room temperature.Furthermore,an appropriate alloy composition enables the formation of a nearly equiaxed dual-phase microstructure in the 17Cr type duplex stainless steel after high-temperature solution treatment.The studied 17Cr-type duplex stainless steel exhibits excellent overall mechanical properties,with a maximum tensile strength exceeding 1 200 MPa in the solution-treated state,elongation after fracture greater than 50％,an impact toughness of 204 J at room temperature,and 99 J at-10 ℃.
duplex stainless steelheat treatmentmicrostructurestability of austenitemechanical property
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维普
