Material number 1.2311: 1.2311
1.2311 is the European material number (Werkstoffnummer, EN 10027-2) for 1.2311, plastic mould steel, pre-hardened and tempered specified in EN ISO 4957.
Reading 1.2311 digit by digit
An EN 10027-2 number has the form 1.XXYY. The leading 1 marks it as steel. The pair 23 is the steel group, and for this number that group is Cr-Mo-V cold-work tool steels. The final pair 11 is a sequential count inside that group and carries no meaning of its own — 1.2311 is simply the 11th entry registered there.
The group digits are the useful part. Reading 23 tells you what kind of steel you are looking at before you know anything else about it, and the 3 other numbers from group 23 held here are listed below.
1.2311 identity card
| Item | Value |
|---|---|
| Material number (EN 10027-2) | 1.2311 |
| Symbolic grade name | 1.2311 |
| Steel group | 23 — Cr-Mo-V cold-work tool steels |
| Sequential number in group | 11 |
| Specified in | EN ISO 4957 |
| Steel family | Tool steel |
| Yield, first condition in the table | ≈ 800–900 MPa (+QT as delivered, section ≤ 250 mm) |
| Tensile, same condition | 1000–1100 MPa |
| Cross-references held | 8 grades in 5 systems |
1.2311 (40CrMnMo7) is the pre-hardened plastic mould steel sold at 28–34 HRC and machined in that condition — no heat treatment, no distortion. Composition, hardness, polishing and P20 equivalents.
Full data sheet for 1.2311 → · Equivalent grades → · EN ISO 4957 →
Group 23 — the neighbouring numbers
Same group digits, so the same broad class of steel. The sequential digits do not rank them.