Cobalt

Chemical symbol: Co. In alloying, this element is used in tool, magnet and heat resisting steels. Together with tungsten and molybdenum, cobalt is used to form the super high-speed steels. It improves the red hardness value of the steel, that is, it enables the steel to resist softening at a high temperature or, in the case of a cutting tool, to hold its edge under severe conditions.