Steel 24CrMo13-6 +QT-250 (+QT)
Heat-treated state
EN 24CrMo13-6
Heavy bar and forging sizes where reduced quench severity lowers guaranteed strength.
Values for the +QT-250 condition
Other 24CrMo13-6 tempers and conditions
24CrMo13-6 is listed in 7 conditions; see the grade overview at 24CrMo13-6.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Delivery state for bar/forging stock that must be heavily machined or cold-worked before quenching and tempering. | 450 | 700 | 20 | 225 HB | — |
Normalized | Grain-refining state for forgings prior to final quench and temper; not a service condition. | 600 | 900 | 15 | 28 HRC | 6.4 % IACS |
Cold drawn | Bright-drawn small bar with close tolerance and good surface for parts machined with minimal stock removal. | 650 | 850 | 10 | 25 HRC | 6.4 % IACS |
+QT | Very large forgings (extruder barrels, big shafts) where through-hardening is limited by mass effect. | 660 | 890 | 15 | 27 HRC | — |
+QT-250This page +QT | Heavy bar and forging sizes where reduced quench severity lowers guaranteed strength. | 760 | 980 | 14 | 31 HRC | — |
+QT-100Default +QT | Standard stock condition: oil/polymer quenched and tempered ~580–650 °C, machined to near-final size, then nitrided. | 870 | 1,080 | 13 | 34 HRC | — |
+QT + gas/plasma nitrided | Final service condition: nitrided 500–540 °C to a compound + diffusion layer for wear and scuffing resistance without distortion. | 870 | 1,080 | 12 | 64 HRC | — |
What is 24CrMo13-6 +QT-250?
24CrMo13-6 +QT-250 is 24CrMo13-6 heat treated to +QT-250 — heavy bar and forging sizes where reduced quench severity lowers guaranteed strength. 24CrMo13-6 +QT-250 has a yield strength of 760 MPa (110 ksi) and a tensile strength of 980 MPa (142 ksi) — stronger than 85% of steel grades. Elongation at break is 14% and the elastic modulus is 210 GPa (30.5 Msi). 24CrMo13-6 +QT-250 has a density of 7.8 g/cm³ (0.282 lb/in³), lighter than 87% of steel grades. It melts at 1,420°C (2,588 °F). +QT-100 is the default condition FabDigit quotes; +QT-250 is available on request or by drawing note.
Advantages
- High service temperature — 500°C (932 °F), better than 90% of steel grades
- High strength — 760 MPa (110 ksi), better than 85% of steel grades
- Polishes to a fine finish — 65/100, better than 78% of steel grades
Limitations
- Limited formability — 15/100, worse than 87% of steel grades
- Difficult to weld — 20/100, worse than 84% of steel grades
- Poor heat conductor — 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades
- Limited ductility — 14%, worse than 75% of steel grades
24CrMo13-6 +QT-250 properties
Typical room-temperature values for 24CrMo13-6 +QT-250; 11 are specific to this condition. Other listed values are 24CrMo13-6 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
24CrMo13-6 +QT-250 has a density of 7.8 g/cm³ (0.282 lb/in³), lighter than 87% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical16
24CrMo13-6 +QT-250 has a yield strength of 760 MPa (110 ksi) and a tensile strength of 980 MPa (142 ksi) — stronger than 85% of steel grades. Elongation at break is 14% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
24CrMo13-6 +QT-250 is rated for continuous service to 500°C (932 °F). It conducts heat at 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades. Thermal expansion is 11.8 µm/m·K (6.56 µin/in·°F).
Electrical2
24CrMo13-6 +QT-250 has an electrical resistivity of 2.7×10⁻⁷ Ω·m.
Chemical & Environmental2
Corrosion resistance is poor (15/100), better than 75% of steel grades.
Sustainability4
Producing a kilogram of 24CrMo13-6 +QT-250 takes about 34 MJ of energy and emits 2.4 kg of CO₂ — more than 82% of steel grades. Typical recycled content is 25%.
Manufacturability7
24CrMo13-6 +QT-250's machinability is fair (45/100, worse than 65% of steel grades); weldability poor (20/100); formability poor (15/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 24CrMo13-6 +QT-250
Is 24CrMo13-6 easy to machine?
Machine in +A for roughing or in +QT at ~330 HB with carbide at moderate speed and rigid setups; leave 0.05–0.15 mm grinding stock because nitriding grows the surface slightly.
Can 24CrMo13-6 be welded?
Essentially not intended for welding; if unavoidable use low-hydrogen or matching filler with 250–350 °C preheat and immediate 600–650 °C PWHT, and never weld after nitriding.
Can 24CrMo13-6 be formed, bent or molded?
Hot forge 1100–850 °C with slow cooling, then normalize and soft anneal; cold forming is impractical above the annealed state.
What surface finishes work on 24CrMo13-6?
Gas or plasma nitride at 500–540 °C after a stress-relief at ~30 °C below the tempering temperature; alternatives are hard chrome, black oxide, or phosphating — anodizing does not apply.
24CrMo13-6 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 | 0.2 – 0.28 | 0.24 |
| Si | ≤ 0.4 | 0.25 |
| Mn | 0.4 – 0.7 | 0.55 |
| P | ≤ 0.03 | — |
| Smax; low-S variants for cleanliness | ≤ 0.04 | — |
| Crprimary nitride former | 3 – 3.5 | 3.25 |
| Mohardenability + temper embrittlement resistance | 0.5 – 0.6 | 0.55 |
| Fe | balance | — |
24CrMo13-6 +QT-250 — frequently asked
What is 24CrMo13-6 +QT-250 used for?
24CrMo13-6 +QT-250 is typically used for nitrided shafts, gear components, machine tool parts and wear-resistant pins. In short: tough-core nitriding steel; high core strength; low corrosion resistance.
What is the yield strength of 24CrMo13-6 +QT-250?
24CrMo13-6 +QT-250 has a typical yield strength of 760 MPa (110 ksi) and a tensile strength of 980 MPa (142 ksi) — stronger than 85% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is 24CrMo13-6 +QT-250 easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 65% of steel grades). Machine in +A for roughing or in +QT at ~330 HB with carbide at moderate speed and rigid setups; leave 0.05–0.15 mm grinding stock because nitriding grows the surface slightly.
Can 24CrMo13-6 +QT-250 be welded?
Not readily — weldability is rated poor (20/100). Essentially not intended for welding; if unavoidable use low-hydrogen or matching filler with 250–350 °C preheat and immediate 600–650 °C PWHT, and never weld after nitriding.
What surface finishes work on 24CrMo13-6 +QT-250?
Gas or plasma nitride at 500–540 °C after a stress-relief at ~30 °C below the tempering temperature; alternatives are hard chrome, black oxide, or phosphating — anodizing does not apply.
Can 24CrMo13-6 +QT-250 be formed, bent or molded?
Hot forge 1100–850 °C with slow cooling, then normalize and soft anneal; cold forming is impractical above the annealed state.
What is the maximum service temperature of 24CrMo13-6 +QT-250?
24CrMo13-6 +QT-250 is rated for continuous use to about 500°C (932 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- EN 10085 — Nitriding steels — Technical delivery conditions — CEN (2001)
- EN 10250-3 — Open die steel forgings, alloy special steels — CEN (1999)
- EN ISO 18265 — Conversion of hardness values — ISO (2013)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASM Handbook Vol.4A — Steel Heat Treating Fundamentals (nitriding) — ASM International (2013)
- Nitriding steel bar datasheets (1.8516 / 1.8519 class) — European special steel producers (2023)
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.