Crucible REX M4 is a special-purpose high-speed tool steel that is designed to provide high wear resistance in tools. Its high vanadium and carbon content provides superior resistance to cratering and wear in cold work punches, die inserts, and cutting applications involving high speed and light cuts. It is designed to give maximum performance while working with abrasive materials, exhibiting better wear resistance than Types M2 or M3. 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-812. Producer or source: Crucible Industries LLC.