H13 steel is the most widely used and most representative hot work die steel grade, its main characteristics are
(1) High hardenability and high toughness.
(2) Excellent resistance to thermal cracking and can be water cooled in the workplace.
(3) medium wear resistance, carburising or nitriding can also be used to improve its surface hardness, but to slightly reduce the resistance to thermal cracking.
(4) Poor secondary hardening ability in tempering due to its low carbon content.
(5) Softening resistance at higher temperatures, but a rapid drop in hardness at operating temperatures above 540°C (1000°F) (i.e. a working temperature of 540°C can be tolerated).
(6) Small deformation from heat treatment.
(7) Moderate and high machinability.
(8) Medium resistance to decarburisation.