What is JIS SKD11 cold work tool steel?

JIS G 4404 SKD11 (1.2379, D2, X153CrMo12) cold work tool steel is a high carbon, high chromium tool steel (12% chrome) with extremely high wear resisting properties, heat treatable to 60-62 Rc.

The mechanical properties of SKD11 cold work tool steel are very sensitive to heat treatment. SKD11 Cold Work Tool Steel is available in de-carb free rounds, flats, and squares, as well as ground flat stock and drill rod.

JIS SKD11 cold work tool steel is very wear resistant but not as tough as lower alloyed steels. SKD11 steel hardens in air with a low order of movement and offers a measure of corrosion resistance when polished. The high percentage of chromium gives it mild corrosion-resisting properties in the hardened condition.