Temper

1) In heat treatment, this process increases the toughness and decreases the hardness of hardened steel or cast iron. It is also applied occasionally to normalized steel. This is done by heating to a temperature below the eutectoid temperature. 2) In tool steels, “temper” is sometimes used, but unadvisedly, to denote the carbon content. 3) In nonferrous alloys and in some ferrous alloys, the term is used to indicate the hardness and strength produced by mechanical and/or thermal treatment, and characterized by a certain structure, mechanical properties, or reduction in area during cold working. A given alloy may be in the fully softened or annealed temper, or it may be cold worked to the hard temper or further to spring temper. Intermediate tempers produced by cold working (rolling or drawing) are called “quarter hard,” “half-hard” and “three-quarters hard” and are determined by the amount of cold reduction and the resulting tensile properties.