H13 Tool Steel Properties, Material Hardness Range & Equivalent

AISI H13 steel is a 5% Cr ultra-high strength tool steel alloy with higher content of molybdenum and vanadium. Molybdenum provides excellent toughness and high hardenability; Vanadium results in a higher degree of dispersion of the hard vanadium carbides, resulting in higher wear resistance. H13 tool steel is a secondary hardening steel. It has good tempering resistance, good thermal fatigue resistance, and excellent heat cracking resistance, and maintains high hardness and strength at elevated temperatures. It is deep hardening and has a very high toughness, which allows hardening of large sections by air cooling. Hot work tools made of H13 material can be safely water cooled in hot work use where thermal shock cracking is not an issue. Its resistance to thermal fatigue, erosion, and wear makes it the mold material of choice for aluminum and magnesium die castings, as well as many other hot working applications. However, H13 metal is subject to hydrogen embrittlement and can be nitrided for additional wear resistance.