Introduction to super martensitic stainless steel 3
- 1.Super martensitic stainless steel has good mechanical properties. The typical yield stress σ2 is 550-850MPa and the tensile strength σb is 780-1000MPa. It has good impact toughness and ductility also. CA6NM is one of these martensitic stainless steel.
- 2.The fibrous structure of super martensitic stainless steel is low carbon tempered martensite. According to the amount of nickel and the difference of heat treatment, the microstructure of some martensitic stainless steel may have retained austenite which is partly refined and dispersed. And maybe a little δ ferrite.
- 3.The carbon content of super martensite stainless steel is better than that of traditional martensitic stainless steel. Meantime increase the amount of nickel and molybdenum in the steel. Therefore it has more improvement of corrosion resistance than the traditional martensitic stainless steel.
- 4.The weldability of super martensitic stainless steel is better than that of traditional martensitic stainless steel. Therefore for welding we can use common welding process. Because super martensitic stainless steels has low carbon and low nitrogen it can directly use after welding. Meanwhile if necessary,it can have post weld heat treatment to obtain lower hardness and better roughness.
- 5.Super martensitic stainless steel is a kind of economical and applicable new steel. Due to its use cost is lower 35%-40% than that of duplex stainless steel. So it has a competitive advantage and bright future.