Effect of annealing on the properties of high-speed steels

Abstract

1. Annealing (at 825–900°) for 24 h for hot-rolled and 15–18 h for cold-rolled high-speed steel lowers the quench hardness, secondary hardness, and red hardness. These properties are much more impaired after annealing at 900° than at 825°. 2. The effect of annealing depends on the amount and composition of M6C carbide, i.e., the chemical composition of the high-speed steel. The properties are most impaired for steel R18, where the carbide contains more tungsten, and less impaired for steels R12 and R6M5. 3. It is recommended that the annealing temperature not be higher than 850–860°, that the load in the furnace be limited so that the annealing time at temperatures over 800° does not exceed 10–18 h, and that the annealing time be still shorter for cold-rolled steels.