Similar steel grade-DIN1.2581, JIS SKD5, GB 3Cr2W8V

Chemical Composition (%)

AISI H21 Hot Work Tool Steel is Tungsten-chrome–vanadium steel for hardening in oil and possibly in air with very good hardenability, very high firmness during the heat and resistance to the tempering.

High resistance to the hot tempering and good toughness.

Lower resistance to tearing of thermal fatigue.

Hiher sensitivity to quick changes of temperature.

The steel is not appropriate for tools cooled by water. It is well-workable during the heat and

well-workable in the soft-annealed state


For tools for highly stressed small pressing dies and die inserts especially for die forging of accurate products from the difficult-workable steels and copper alloys, thorns and jaws for forging presses, forgings for swaging,.

Tools for production of rivets, nuts and screws, small extrusion dies (matrixes), thorns, pressing discs for extrusion of alloys of non-ferrous metals.

Tools for hot cutting such as small shear blades, punching dies, small trimming dies.