AISI is a water-hardening tool steel that resists wear and abrasion from four to ten times longer than plain carbon tool steels. When hardened, it acquires a hard-slippery surface that is difficult to scratch. Its many uses for tools include dies for a variety of products, reamers and finishing tools. This datasheet provides information on composition, physical properties, hardness, and elasticity. It also includes information on forming, heat treating, machining, and surface treatment. Filing Code: TS-298. Producer or source: Tool steel mills.