AISI 1055 is a high-carbon oil or water-hardening tool and machinery steel recommended for hand tools, agricultural tools and machinery, shafts, springs and heavy-machinery parts. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: CS-49. Producer or source: Carbon steel mills.