ALLEGHENY AL 609 is a shock-resisting steel of the silico-manganese type. It has the ability to withstand heavy shocks before bending or breaking. It is equivalent to AISI Type S5 tool steel. This datasheet provides information on composition, hardness, and tensile properties as well as fracture toughness. It also includes information on forming, heat treating, and machining. Filing Code: TS-46. Producer or source: Allegheny Ludlum Corporation.