Martensitic steels
Martensitic stainless steels are Chromium alloys (about 11% to 18%) with relatively high carbon content (up to 1.1% in weight) containing small amounts of other elements. They are generally known as the AISI 400 series in the United States.
Typical elements found in the alloy are: Manganese, Silicon, Chromium and Molybdenum; sulphur may also be added to improve machinability with chip removal machines, albeit with some compromise to the mechanical properties.
Martensitic stainless steel exhibits exceptionally high mechanical properties and can be easily machined using machine tools. Unlike other stainless steels, it is capable of undergoing heat treatment to further enhance its mechanical properties, including tensile strength, yield strength and hardness.
These steels have a crystalline structure featuring a body-centred cubic lattice (BCC), which makes them magnetic.