AISI Type H21 is a tungsten-chromium hot-work tool and die steel having good red-hardness and resistance to abrasion with relatively good shock resistance. It will withstand high operating temperatures up to 1000 F for long periods of time. This datasheet provides information on composition, physical properties, hardness, and elasticity as well as fracture toughness. It also includes information on high temperature performance as well as forming, heat treating, and joining. Filing Code: TS-236. Producer or source: Tool steel mills.