Tool steel
D2 Tool Steel
Manufacturer or standards-body identification; product values do not apply to every form or condition.
Identity / state reference
What distinguishes this material
K110 identifies D2/1.2379. Its producer offers plate and long products but expressly scopes the displayed technical data to long products.
- Designation in this reference
- D2
- Forms covered by the sources
- K110 long products and plates, with separate data applicability.
- States to distinguish or confirm
- Obtain delivery anneal and final hardening/tempering requirements.
- Temperature and exposure
- No universal service-temperature limit or room-temperature property set is assigned. Use the cited product document and the purchase certificate.
Property evidence for a stated condition
No condition-specific numerical table is reproduced here
The linked sources establish the identity and the stated product/state scope. Obtain the row for your actual form, section, treatment and test conditions before adopting strength, hardness or a thermal limit.
Resolve these conditions next
- What product standard, edition and complete grade are on the material certificate?
- What product form, section size and delivery/heat-treatment condition will be machined?
For machining, take the exact grade, supplied condition and measured hardness where applicable into the tool maker’s application data. A generic material-family speed is not a substitute for an operation and tool-specific recommendation.
Sources and what they establish
Reviewed 23 October 2026. A source’s publication date and the review date are different. The scope below identifies the fields checked.
BÖHLER K110
D2 / 1.2379; listed long products and plates, but supplied technical data expressly scoped to long products.
BÖHLER K110 ↗Source identity, a named product example and a supplied-batch certificate are different evidence. Cross-standard similarity does not approve substitution.
Corrections from the previous article
- Do not apply long-product properties to plate without confirmation; remove the blanket final HRC value.
- Withdraw the legacy generic hardness (210–240 HB (annealed)) and tensile-strength (2,300 MPa (335 ksi) hardened) pair: the old page does not establish a matching product, heat treatment, section and test source.
- Remove the unsupported cutting-speed table and machinability percentage; select tooling only after the actual material condition is known.
Check a machining-process term
If EDM is part of the manufacturing route, distinguish that process from the material grade and heat treatment.