No. 484 tool steel is an air hardening tool steel capable of through hardening in heavy sections. Isothermal transformation of material austenitized at 1750 starts after about 400 seconds at 1300 F and after about 1000 seconds at 600 F. The calculated Ms temperature is 325 F. The steel has a good hardness/toughness balance. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on wear resistance as well as forming, heat treating, and machining. Filing Code: TS-501. Producer or source: Carpenter.