It is a hardenable stainless steel with high hardness, strength and wear resistance, but has poor toughness and weldability. Ordinary martensitic stainless steel lacks sufficient ductility and is very sensitive to stress during deformation, and cold forming is difficult. Super martensitic stainless steel can be obtained by reducing the carbon content and increasing the nickel content. In recent years, countries have invested heavily in the development of low-carbon, low-nitrogen super martensitic steels, and have developed a number of super martensitic steels for different purposes. Super martensitic steel has been widely used in oil and gas exploration, storage and transportation equipment, hydropower, chemical and high temperature pulp production equipment.