Martensitic stainless steels,

Definition of Martensitic stainless steels:

1. Contain high amounts of chromium but very little nickel or other alloying metal. These steels can be hardened by heat treatment which make them stronger as well as more brittle. Designated as 400 series, they are used mainly for surgical instruments and in oil industry. Named after German researcher Adolf Martens who in 1890 discovered their orthorhombic molecular structure.