MONARK-2 is a silico-manganese, shock resisting tool steel, designed for applications where high toughness, at high hardness levels, is required to withstand severe impact. This datasheet provides information on composition, hardness, and tensile properties as well as fracture toughness. It also includes information on forming, heat treating, machining, and joining. Filing Code: TS-69. Producer or source: Atlas Steels Company.