Steel 12CrMoV12-10 +QT (Quenched and tempered)
Heat-treated state · default condition
EN 12CrMoV12-10
Standard supply condition for hydroprocessing reactor plate, forgings and pipe — best balance of creep strength, toughness and HTHA resistance.
Values for the +QT condition
Other 12CrMoV12-10 tempers and conditions
12CrMoV12-10 is listed in 5 conditions; see the grade overview at 12CrMoV12-10.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Softest supply condition for heavy machining or forming of forgings before final quench-and-temper. | 350 | 570 | 24 | 175 HB | — |
Normalized and tempered | Choose for very heavy sections or where quenching is impractical; slightly lower strength and toughness than +QT but full creep capability. | 430 | 620 | 20 | 14 HRC | — |
+QT + simulated post-weld heat treatment | Ordered for reactor shells where the mill must guarantee properties after the fabricator's full PWHT cycle (e.g. 690–710 °C, long hold) plus step-cooling embrittlement test. | 460 | 630 | 21 | 195 HB | — |
+QTDefaultThis page Quenched and tempered | Standard supply condition for hydroprocessing reactor plate, forgings and pipe — best balance of creep strength, toughness and HTHA resistance. | 500 | 670 | 20 | 20 HRC | — |
+QT high-strength class | Lower tempering temperature for higher room-temperature strength in thinner shells; slightly reduced toughness margin and PWHT latitude. | 560 | 730 | 18 | 22 HRC | — |
What is 12CrMoV12-10 +QT?
12CrMoV12-10 +QT is 12CrMoV12-10 heat treated to +QT — standard supply condition for hydroprocessing reactor plate, forgings and pipe — best balance of creep strength, toughness and HTHA resistance. 12CrMoV12-10 +QT has a yield strength of 500 MPa (72.5 ksi) and a tensile strength of 670 MPa (97.2 ksi) — stronger than 63% of steel grades. Elongation at break is 20% and the elastic modulus is 210 GPa (30.5 Msi). 12CrMoV12-10 +QT has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,450°C (2,642 °F).
Advantages
- Tough — resists crack growth — 180 MPa·√m (163.8 ksi·√in), better than 99% of steel grades
- High service temperature — 540°C (1,004 °F), better than 93% of steel grades
- Good corrosion resistance — 25/100, better than 92% of steel grades
Limitations
- Low electrical conductivity — 5 % IACS, worse than 82% of steel grades
12CrMoV12-10 +QT properties
Typical room-temperature values for 12CrMoV12-10 +QT; 17 are specific to this condition. Other listed values are 12CrMoV12-10 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
12CrMoV12-10 +QT has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,450°C (2,642 °F).
Mechanical17
12CrMoV12-10 +QT has a yield strength of 500 MPa (72.5 ksi) and a tensile strength of 670 MPa (97.2 ksi) — stronger than 63% of steel grades. Elongation at break is 20% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
12CrMoV12-10 +QT is rated for continuous service to 540°C (1,004 °F). It conducts heat at 38 W/m·K (22 BTU/hr·ft·°F), worse than 69% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
12CrMoV12-10 +QT conducts electricity at 5 % IACS, worse than 82% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (25/100), better than 92% of steel grades.
Sustainability4
Producing a kilogram of 12CrMoV12-10 +QT takes about 32 MJ of energy and emits 2.2 kg of CO₂ — more than 70% of steel grades. Typical recycled content is 25%.
Manufacturability7
12CrMoV12-10 +QT's machinability is fair (45/100, worse than 65% of steel grades); weldability fair (45/100); formability fair (40/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 12CrMoV12-10 +QT
Is 12CrMoV12-10 easy to machine?
Machines like a 200 HB Q&T Cr-Mo steel — rigid setups, carbide inserts at 80–140 m/min, positive rake and generous coolant; abrasive V-carbides shorten tool life versus plain 2.25Cr-1Mo.
Can 12CrMoV12-10 be welded?
SAW/SMAW/GTAW with matching 3Cr-1Mo-V (e.g. B23V-type) consumables, preheat/interpass 200–250 °C, strict low-hydrogen practice, and PWHT ~690–720 °C; step-cooling and J-factor/X-bar limits are normally specified.
Can 12CrMoV12-10 be formed, bent or molded?
Hot form at 950–1150 °C followed by full re-austenitizing, quench and temper; cold forming limited to gentle rolling of thin sections because of high yield strength and section thickness.
What surface finishes work on 12CrMoV12-10?
No anodizing; external surfaces are shot-blasted and painted or aluminized, while process surfaces are typically weld-overlaid with 309L/347 stainless.
12CrMoV12-10 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 | 0.1 – 0.15 | 0.13 |
| Sikept low for temper-embrittlement and HTHA resistance | ≤ 0.1 | 0.06 |
| Mn | 0.3 – 0.6 | 0.45 |
| PJ-factor / X-bar restrictions usually apply | ≤ 0.01 | 0.01 |
| S | ≤ 0.01 | 0 |
| Cr | 2.75 – 3.25 | 3 |
| Mo | 0.9 – 1.1 | 1 |
| Vfine V carbides give creep and HTHA resistance | 0.2 – 0.3 | 0.25 |
| Ni | ≤ 0.25 | 0.1 |
| Cu | ≤ 0.25 | 0.1 |
| TiTi-B variant; Nb (Cb) 0.015–0.070 in the A832 Gr.21V variant | 0.02 – 0.04 | 0.03 |
| B | 5×10⁻⁴ – 0 | 0 |
| Al | ≤ 0.02 | 0.01 |
| Fe | balance | — |
12CrMoV12-10 +QT — frequently asked
What is 12CrMoV12-10 +QT used for?
12CrMoV12-10 +QT is typically used for steam turbine rotors, high-pressure boiler components, petrochemical pressure vessels and high-temperature bolting. In short: creep-resisting Cr-Mo-V forging steel; service to 540 °C; strict preheat and PWHT.
What is the yield strength of 12CrMoV12-10 +QT?
12CrMoV12-10 +QT has a typical yield strength of 500 MPa (72.5 ksi) and a tensile strength of 670 MPa (97.2 ksi) — stronger than 63% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is 12CrMoV12-10 +QT easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 65% of steel grades). Machines like a 200 HB Q&T Cr-Mo steel — rigid setups, carbide inserts at 80–140 m/min, positive rake and generous coolant; abrasive V-carbides shorten tool life versus plain 2.25Cr-1Mo.
Can 12CrMoV12-10 +QT be welded?
With care — weldability is rated fair (45/100). SAW/SMAW/GTAW with matching 3Cr-1Mo-V (e.g. B23V-type) consumables, preheat/interpass 200–250 °C, strict low-hydrogen practice, and PWHT ~690–720 °C; step-cooling and J-factor/X-bar limits are normally specified.
What surface finishes work on 12CrMoV12-10 +QT?
No anodizing; external surfaces are shot-blasted and painted or aluminized, while process surfaces are typically weld-overlaid with 309L/347 stainless.
Can 12CrMoV12-10 +QT be formed, bent or molded?
Hot form at 950–1150 °C followed by full re-austenitizing, quench and temper; cold forming limited to gentle rolling of thin sections because of high yield strength and section thickness.
What is the maximum service temperature of 12CrMoV12-10 +QT?
12CrMoV12-10 +QT is rated for continuous use to about 540°C (1,004 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- EN 10028-2 — Flat products for pressure purposes, Part 2: steels with specified elevated-temperature properties — CEN (2017)
- ASTM A542/A542M — Pressure Vessel Plates, Alloy Steel, Quenched and Tempered, Cr-Mo and Cr-Mo-V — ASTM International (2019)
- ASTM A832/A832M — Pressure Vessel Plates, Alloy Steel, Cr-Mo-V (Grade 21V) — ASTM International (2019)
- API RP 934-A — Materials and Fabrication of 2¼Cr-1Mo, 2¼Cr-1Mo-¼V, 3Cr-1Mo and 3Cr-1Mo-¼V Steel Heavy Wall Pressure Vessels — American Petroleum Institute (2019)
- ASME BPVC Section II Part D — physical and allowable stress data for 3Cr-1Mo steels — ASME (2023)
- Heavy plate for hydroprocessing reactors, 3Cr-1Mo-0.25V grades — Dillinger / JSW Steel heavy-plate datasheets (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.