AISI 8645 is a triple-alloy steel of the oil-hardening type. Its good hardenability and strength make it suitable for axles, shafts and a wide variety of other engineering uses. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: SA-279. Producer or source: Alloy steel mills and foundries.