Steel 1.2311 · heat-treated state
Steel 1.2311 Q&T
Properties of the Q&T condition, compared with the other 1.2311 tempers.
Choose when higher wear resistance or higher core strength than pre-hard is needed in small/medium sections; accept distortion and re-machining.
What is 1.2311 Q&T?
1.2311 Q&T is 1.2311 heat treated to Q&T — choose when higher wear resistance or higher core strength than pre-hard is needed in small/medium sections; accept distortion and re-machining. 1.2311 Q&T has a yield strength of 1,150 MPa (167 ksi) and a tensile strength of 1,350 MPa (196 ksi) — stronger than 94% of steel grades. Elongation at break is 10% and the elastic modulus is 205 GPa (29.7 Msi). 1.2311 Q&T 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). Annealed is the default condition FabDigit quotes; Q&T is available on request or by drawing note.
Advantages
- High strength — 1,150 MPa (167 ksi), better than 94% of steel grades
- Polishes to a fine finish — 65/100, better than 78% of steel grades
Limitations
- Limited ductility — 10%, worse than 91% of steel grades
- Difficult to machine — 30/100, worse than 89% of steel grades
- Limited service temperature — 250°C (482 °F), worse than 85% of steel grades
- Low fracture toughness — 55 MPa·√m (50.1 ksi·√in), worse than 83% of steel grades
- Poor heat conductor — 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades
1.2311 Q&T properties
Typical room-temperature values for 1.2311 Q&T — 14 properties are specific to this condition; the rest are grade-level values shared by every 1.2311 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
1.2311 Q&T 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 Q&T has a yield strength of 1,150 MPa (167 ksi) and a tensile strength of 1,350 MPa (196 ksi) — stronger than 94% of steel grades. Elongation at break is 10% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal5
1.2311 Q&T is rated for continuous service to 250°C (482 °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 Q&T conducts electricity at 7.8 % IACS, worse than 58% 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 Q&T 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 Q&T's machinability is poor (30/100, worse than 89% of steel grades); weldability poor (25/100); formability poor (30/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 1.2311 tempers and conditions
1.2311 is also supplied in 3 other conditions. The full side-by-side table is on the 1.2311 overview.
- AnnealedDefaultPick for heavy machining, deep cavity sinking or when the part will be hardened and tempered after machining.500 MPa yield · 20 HRC
- Q&TChoose when higher wear resistance or higher core strength than pre-hard is needed in small/medium sections; accept distortion and re-machining.1,150 MPa yield · 41 HRC
- PrehardStandard stock condition: machine the finished mould directly, no further heat treatment or distortion risk.860 MPa yield · 31 HRC
- Prehard+NitridedUse for abrasive or glass-filled plastics: nitrided case raises surface wear and corrosion resistance while the pre-hard core keeps its toughness.860 MPa yield · 31 HRC
Working with 1.2311 Q&T
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.
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.
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 | — |
1.2311 Q&T — frequently asked
What is 1.2311 Q&T used for?
1.2311 Q&T 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 Q&T?
1.2311 Q&T has a typical yield strength of 1,150 MPa (167 ksi) and a tensile strength of 1,350 MPa (196 ksi) — stronger than 94% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is 1.2311 Q&T easy to machine?
Not especially — machinability is rated poor (30/100, worse than 89% 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 Q&T be welded?
Not readily — weldability is rated poor (25/100). 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 Q&T?
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 Q&T 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 Q&T?
1.2311 Q&T is rated for continuous use to about 250°C (482 °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.
Can FabDigit make parts in 1.2311 Q&T?
Yes — 1.2311 Q&T is available for CNC machining with instant online pricing. 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. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.