Nu-Die® V (AISI H13) has been the most popular, and perhaps the most versatile hot work tool steel available for many years. It provides a good balance of toughness, heat check resistance and temper resistance, along with moderate wear resistance. It is air hardenable and is used in most applications in the heat treated condition at HRC 44-52. The normal tempering temperatures for Nu-Die V are quite high (>1000°F, 540°C), allowing it to retain its heat treated hardness and strength while in service at elevated temperatures. Nu-Die V may be used for tool temperatures up to about 1000°F (540°C) with brief exposures up to 1100°F (595°C), making it ideal for forging
dies, hot extrusion tooling, and die casting dies. Crucible offers two premium versions, Nu-Die XL and Nu-Die ESR, for applications requiring critical polishability, improved heat check resistance and better transverse toughness