Steel 1.2311
EN 1.2311
1.2311 (40CrMnMo7, close to AISI P20) is a Cr-Mn-Mo pre-hardened plastic mould steel supplied quenched and tempered to about 280-325 HB (28-34 HRC), so blocks can be roughed, finished and put into service without further heat treatment.
Values for the Annealed condition
1.2311 tempers and conditions
1.2311 is supplied in 4 conditions, soft to hard. Annealed is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefault soft annealed (≤235 HB) | Pick for heavy machining, deep cavity sinking or when the part will be hardened and tempered after machining. | 500 | 760 | 20 | 20 HRC | — |
Pre-hardened | Standard stock condition: machine the finished mould directly, no further heat treatment or distortion risk. | 860 | 1,030 | 14 | 31 HRC | — |
pre-hardened core with gas/plasma nitrided case (~600–750 HV) | Use for abrasive or glass-filled plastics: nitrided case raises surface wear and corrosion resistance while the pre-hard core keeps its toughness. | 860 | 1,030 | 31 HRC | — | |
Quenched and tempered | Choose when higher wear resistance or higher core strength than pre-hard is needed in small/medium sections; accept distortion and re-machining. | 1,150 | 1,350 | 10 | 41 HRC | — |
What is 1.2311?
1.2311 (40CrMnMo7, close to AISI P20) is a Cr-Mn-Mo pre-hardened plastic mould steel supplied quenched and tempered to about 280-325 HB (28-34 HRC), so blocks can be roughed, finished and put into service without further heat treatment. It is dimensionally stable and responds well to polishing and EDM, which suits medium and large injection moulds, die-casting auxiliary parts, rubber moulds and tooling plate; annealed reference data are 500 MPa yield, 760 MPa tensile, 20 % elongation and 220 HB. It is not stainless, the hardness ceiling is modest for high-wear or mirror-finish cavities and through-hardening in heavy sections is limited — use 1.2738 or 1.2312 for those cases. 1.2311 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F). 1.2311 has a yield strength of 500 MPa (72.5 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 63% of steel grades. Elongation at break is 20% and the elastic modulus is 205 GPa (29.7 Msi).
What is 1.2311 used for?
- Injection mould cavity and core plates
- Mould inserts
- Bolsters and mould frames
- Rubber moulding tools
- Die-casting auxiliary components
- Tooling and jig plates
- Ejector and slide blocks
Advantages
- Polishes to a fine finish — 65/100, better than 78% of steel grades
Limitations
- Poor heat conductor — 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades
1.2311 properties
Typical room-temperature values for 1.2311-Annealed; bars are the position among steel grades.
Physical3
1.2311 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical16
1.2311 has a yield strength of 500 MPa (72.5 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 63% of steel grades. Elongation at break is 20% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal5
1.2311 is rated for continuous service to 350°C (662 °F). It conducts heat at 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades. Thermal expansion is 12.4 µm/m·K (6.89 µin/in·°F).
Electrical3
1.2311 conducts electricity at 7.8 % IACS, worse than 57% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 1.2311 takes about 34 MJ of energy and emits 2.4 kg of CO₂ — more than 82% of steel grades. Typical recycled content is 30%.
Manufacturability6
1.2311's machinability is good (60/100, better than 83% of steel grades); weldability fair (50/100); formability poor (30/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. 1.2311 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 1.2311
Is 1.2311 easy to machine?
Machines well at 28–34 HRC with coated carbide (roughing ~120–180 m/min, rigid setup); avoid dwelling and use positive rake to prevent work hardening; EDM and deep-hole drilling are routine for cooling channels.
Can 1.2311 be welded?
Repair-weldable with matched low-alloy or maraging filler: preheat 300–350 °C, weld hot, then stress relieve ~30 °C below the last tempering temperature to avoid HAZ cracking.
Can 1.2311 be formed, bent or molded?
Not a forming grade — supplied as pre-hardened plate/block and shaped only by machining; hot work above 900 °C and slow-cool if re-forging.
Manufacturability
The process limits FabDigit applies to 1.2311. Every 1.2311 part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Better60 / 100 |
|---|---|
| ISO material group | P.2 |
| Cutting speed (rough / finish) | 180 / 210 m/min |
| Minimum wall | 0.8 mm |
| Minimum internal radius | 1 mm |
| Drill depth limit | 5× diameter |
| Best surface (machined / polished) | Ra 1.6 / — |
| Hardenable after machining | No |
1.2311 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| C | 0.35 – 0.45 | 0.4 |
| Si | 0.2 – 0.4 | 0.3 |
| Mn | 1.3 – 1.6 | 1.45 |
| Cr | 1.8 – 2.1 | 1.95 |
| Mo | 0.15 – 0.25 | 0.2 |
| P | ≤ 0.03 | |
| Smax; the S-bearing free-machining version is 1.2312 (0.05–0.10 S) | ≤ 0.03 | |
| Fe | balance |
What surface finishes work on 1.2311?
Takes a good hand polish to ~Ra 0.05 µm (lower than ESR grades due to inclusions); commonly gas/plasma nitrided or hard-chrome / electroless-nickel plated for wear and corrosion protection, and must be oiled in storage.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Plating
CVD Coating
Black / Phosphate
Thermal Spray
How much does 1.2311 cost?
1.2311 is a standard-cost steel ($$), cheaper than about 59% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
1.2311 — frequently asked
What is 1.2311 used for?
1.2311 is typically used for injection mould cavity and core plates, mould inserts, bolsters and mould frames, rubber moulding tools, die-casting auxiliary components and tooling and jig plates. In short: workhorse mold-cavity plate.
What is the yield strength of 1.2311?
1.2311 has a typical yield strength of 500 MPa (72.5 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 63% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is 1.2311 easy to machine?
Reasonably — machinability is rated good (60/100, better than 83% of steel grades). Machines well at 28–34 HRC with coated carbide (roughing ~120–180 m/min, rigid setup); avoid dwelling and use positive rake to prevent work hardening; EDM and deep-hole drilling are routine for cooling channels.
Can 1.2311 be welded?
With care — weldability is rated fair (50/100). Repair-weldable with matched low-alloy or maraging filler: preheat 300–350 °C, weld hot, then stress relieve ~30 °C below the last tempering temperature to avoid HAZ cracking.
What surface finishes work on 1.2311?
Takes a good hand polish to ~Ra 0.05 µm (lower than ESR grades due to inclusions); commonly gas/plasma nitrided or hard-chrome / electroless-nickel plated for wear and corrosion protection, and must be oiled in storage.
Can 1.2311 be formed, bent or molded?
Not a forming grade — supplied as pre-hardened plate/block and shaped only by machining; hot work above 900 °C and slow-cool if re-forging.
What is the maximum service temperature of 1.2311?
1.2311 is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.2311 Annealed and 1.2311 Prehard?
Annealed is the default condition — pick for heavy machining, deep cavity sinking or when the part will be hardened and tempered after machining. Prehard: standard stock condition: machine the finished mould directly, no further heat treatment or distortion risk. Yield strength is 500 MPa in Annealed versus 860 MPa in Prehard.
How much does 1.2311 cost?
1.2311 is a standard-cost steel ($$), cheaper than about 59% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Can FabDigit make parts in 1.2311?
Yes — 1.2311 is available for CNC machining; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- EN ISO 4957 — Tool steels (40CrMnMo7, 1.2311) — ISO/CEN (2018)
- GB/T 1299 — (3Cr2MnMo / P20 equivalent) — SAC (2014)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASM Specialty Handbook — Tool Materials — ASM International (1995)
- Böhler M201 / Uddeholm Impax-class pre-hardened mould steel data — voestalpine / Uddeholm (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.