420F stainless steel is a martensitic alloy and is identical to 420 stainless steel, but with an addition of Sulfur (Type 2) to dramatically improve the machinability. This alloy has excellent corrosion properties when hardened and offers good ductility in the annealed condition. This grade is used in similar applications to 420 but where complex geometries require good machining requirements such as dental and surgical equipment. (UNS S42020)
