text: One of a number of compounds of chromium and carbon, with or without limited amounts of other metallic elements when occurring in steel, appearing as separated phase in chromium steels and stainless steels.
  A surface treatment at elevated temperature, generally carried out in pack, vapor, or salt bath, in which an alloy is formed by the inward diffusion of chromium into the base metal.
  Stainless steels are classified into five distinct groups, namely: austenitic, ferritic, martensitic, precipitation hardenable and duplex.
  Chemical symbol Co. Element No. 27 of the periodic system; atomic weight 58.94. A gray magnetic metal, of medium hardness; it resists corrosion like nickel, which it resembles closely; melting point 2696°F.; specific gravity 8.9. It is used as the matrix metal in most cemented carbides and is occasionally electroplated instead of nickel, the sulfate being used as electrolyte. Its principal function as an alloy in tool steel; it contributes to red hardness by hardening ferrite.
  Surface condition characterized by a series of wide spaced lines generally caused by reels used in uncoiling.