D2 tool steel
Also called: 1.2379, X153CrMo12, SKD11, HCHCr, D2 die steel, cold work tool steel
D2 is a high-carbon, high-chromium cold-work tool steel (often called HCHCr in India), equivalent to 1.2379 and SKD11. Hardened to about 58–62 HRC it resists wear very well, which makes it the standard steel for blanking and piercing dies and punches.
Quick facts
- Type
- Cold-work tool steel (high carbon, high chromium)
- Main alloys
- About 1.5% carbon, 12% chromium, plus molybdenum and vanadium
- Working hardness
- About 58–62 HRC
- As supplied
- Annealed, about 255 HB max, for machining
- Wear resistance
- Very high
- Toughness
- Moderate: can chip under heavy shock
Equivalent grades
| Standard | Closest grade |
|---|---|
| AISI | D2 |
| DIN / EN ISO 4957 | 1.2379 (X153CrMoV12) |
| JIS | SKD11 |
| India (trade name) | HCHCr (high carbon high chromium) |
Typical chemical composition (1.2379)
| Element | % |
|---|---|
| Carbon (C) | 1.45–1.60 |
| Chromium (Cr) | 11.0–13.0 |
| Molybdenum (Mo) | 0.70–1.00 |
| Vanadium (V) | 0.70–1.00 |
Heat treatment
- Hardening: about 1000–1040 °C, cooled in air, gas (vacuum) or oil
- Tempering: low (about 150–250 °C) for maximum hardness, or high (about 500–540 °C, twice or more) for better stability and toughness
- Vacuum hardening keeps the surface clean and limits distortion
- After hardening, wire-cut parts benefit from a stress relief to avoid cracking
Typical uses
- Blanking, piercing and trimming dies and punches
- Progressive die inserts
- Shear blades and slitting knives
- Thread rolling dies
- Gauges and wear parts
D2 or other tool steels?
- More toughness for heavy blows: S7 or a more shock-resistant steel
- Hot work (die casting, forging): H13
- Plastic moulds: P20 or 1.2738
- Longest wear life: powder-metallurgy tool steels
Need parts made in D2 tool steel?
Post your requirement free. Workshops that take your kind of work see it and get in touch. You only talk to the ones that fit.
Get startedRelated
Machines
Questions
- What is HCHCr steel?
- The common Indian name for D2 (1.2379): a high-carbon, high-chromium cold-work tool steel used for dies and punches.
- What hardness should D2 be hardened to?
- Typically 58–62 HRC for dies and punches. Slightly lower hardness gives more toughness where chipping is a problem.
- Can D2 be wire cut after hardening?
- Yes, that is common. A stress relief before wire cutting, and leaving enough material around the cut, reduce the risk of cracking.
The figures on this page are typical values for guidance, written by Diemeco from standard engineering practice. They are not a specification: confirm grades and properties with the relevant standard or the supplier's mill test certificate, and tolerances with your workshop. Last checked 8 October 2026.