Steel 12CrMoV-A (Solution annealed)
Temper
GB 12CrMoV
Softest condition for heavy machining, deep forming or re-heat-treatment of bar and forgings.
Values for the A condition
Other 12CrMoV tempers and conditions
12CrMoV is listed in 5 conditions; see the grade overview at 12CrMoV.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AThis page Solution annealed | Softest condition for heavy machining, deep forming or re-heat-treatment of bar and forgings. | 255 | 470 | 28 | 137 HB | — |
N+TDefault Normalized and tempered | Standard delivery condition for GB/T 5310 high-pressure boiler tube and steam piping; best creep and impact balance. | 300 | 540 | 25 | 155 HB | — |
Hot rolled | Cheapest mill condition for stock that will be re-heat-treated after machining; properties not creep-qualified. | 320 | 560 | 22 | 170 HB | 8 % IACS |
Cold drawn | Cold-drawn small-diameter tubing and bar with tighter tolerance and better surface; higher strength, lower ductility. | 470 | 620 | 16 | 190 HB | 8 % IACS |
Quenched and tempered | Choose for bolting, turbine fasteners and forgings needing higher room-temperature strength than the N+T tube condition. | 550 | 700 | 18 | 20 HRC | — |
What is 12CrMoV-A?
12CrMoV-A is 12CrMoV in the A temper — softest condition for heavy machining, deep forming or re-heat-treatment of bar and forgings. 12CrMoV-A has a yield strength of 255 MPa (37 ksi) and a tensile strength of 470 MPa (68.2 ksi) — weaker than 93% of steel grades. Elongation at break is 28% and the elastic modulus is 210 GPa (30.5 Msi). 12CrMoV-A has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,470°C (2,678 °F). N+T is the default condition FabDigit quotes; A is available on request or by drawing note.
Advantages
- High service temperature — 540°C (1,004 °F), better than 93% of steel grades
- Easy to machine — 64/100, better than 92% of steel grades
- Ductile — tolerates forming and impact — 28%, better than 89% of steel grades
- Tough — resists crack growth — 120 MPa·√m (109.2 ksi·√in), better than 81% of steel grades
- Forms and bends easily — 62/100, better than 78% of steel grades
Limitations
- Low strength — 255 MPa (37 ksi), worse than 93% of steel grades
12CrMoV-A properties
Typical room-temperature values for 12CrMoV-A; 11 are specific to this condition. Other listed values are 12CrMoV reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
12CrMoV-A has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,470°C (2,678 °F).
Mechanical16
12CrMoV-A has a yield strength of 255 MPa (37 ksi) and a tensile strength of 470 MPa (68.2 ksi) — weaker than 93% of steel grades. Elongation at break is 28% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
12CrMoV-A is rated for continuous service to 540°C (1,004 °F). It conducts heat at 41 W/m·K (23.7 BTU/hr·ft·°F), worse than 62% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
12CrMoV-A conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (16/100), better than 79% of steel grades.
Sustainability4
Producing a kilogram of 12CrMoV-A takes about 27 MJ of energy and emits 2.1 kg of CO₂ — less than 59% of steel grades. Typical recycled content is 30%.
Manufacturability7
12CrMoV-A's machinability is good (64/100, better than 92% of steel grades); weldability good (60/100); formability good (62/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 12CrMoV-A
Is 12CrMoV easy to machine?
Machines like normalized 4130 at ~60 % of AISI 1212 — rigid setups, carbide tooling, moderate speeds; vanadium carbides accelerate tool wear versus plain Cr-Mo.
Can 12CrMoV be welded?
Weldable by TIG/SMAW with matching Cr-Mo-V filler, preheat 200–300 °C and mandatory PWHT 720–750 °C; watch for reheat (stress-relief) cracking in thick sections and HAZ hardening.
Can 12CrMoV be formed, bent or molded?
Hot bend/forge at 1100–850 °C followed by re-normalizing and tempering; cold tube bending is possible on thin wall but needs stress relief.
What surface finishes work on 12CrMoV?
No anodizing — descale by pickling or shot blast, then aluminize, phosphate or apply high-temperature silicone/aluminium paint for outdoor and flue-gas surfaces.
12CrMoV 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 | 0.08 – 0.15 | 0.12 |
| Si | 0.17 – 0.37 | 0.27 |
| Mn | 0.4 – 0.7 | 0.55 |
| Cr | 0.3 – 0.6 | 0.45 |
| Mo | 0.25 – 0.35 | 0.3 |
| Vcarbide former giving creep strength | 0.15 – 0.3 | 0.22 |
| P | ≤ 0.03 | — |
| S | ≤ 0.01 | — |
| Niresidual max | ≤ 0.25 | — |
| Curesidual max | ≤ 0.2 | — |
| Fe | balance | — |
12CrMoV-A — frequently asked
What is 12CrMoV-A used for?
12CrMoV-A is typically used for boiler tubes, steam pipes and high-temperature fasteners. In short: creep-resistant to 570 °C; boiler and steam-pipe grade; needs mandatory PWHT.
What is the yield strength of 12CrMoV-A?
12CrMoV-A has a typical yield strength of 255 MPa (37 ksi) and a tensile strength of 470 MPa (68.2 ksi) — weaker than 93% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is 12CrMoV-A easy to machine?
Reasonably — machinability is rated good (64/100, better than 92% of steel grades). Machines like normalized 4130 at ~60 % of AISI 1212 — rigid setups, carbide tooling, moderate speeds; vanadium carbides accelerate tool wear versus plain Cr-Mo.
Can 12CrMoV-A be welded?
Yes — weldability is rated good (60/100). Weldable by TIG/SMAW with matching Cr-Mo-V filler, preheat 200–300 °C and mandatory PWHT 720–750 °C; watch for reheat (stress-relief) cracking in thick sections and HAZ hardening.
What surface finishes work on 12CrMoV-A?
No anodizing — descale by pickling or shot blast, then aluminize, phosphate or apply high-temperature silicone/aluminium paint for outdoor and flue-gas surfaces.
Can 12CrMoV-A be formed, bent or molded?
Hot bend/forge at 1100–850 °C followed by re-normalizing and tempering; cold tube bending is possible on thin wall but needs stress relief.
What is the maximum service temperature of 12CrMoV-A?
12CrMoV-A 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.
What is the difference between 12CrMoV N+T and 12CrMoV-QT?
N+T is the default condition — standard delivery condition for GB/T 5310 high-pressure boiler tube and steam piping; best creep and impact balance. QT: choose for bolting, turbine fasteners and forgings needing higher room-temperature strength than the N+T tube condition. Yield strength is 300 MPa in N+T versus 550 MPa in QT.
Sources
- GB/T 5310 — Seamless steel tubes for high pressure boilers — SAC (China) (2017)
- GB/T 3077 — Alloy structural steels — SAC (China) (2015)
- ASTM A335/A335M — Seamless ferritic alloy-steel pipe for high-temperature service (P11 comparison) — ASTM (2023)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.13 — Corrosion — ASM International (2005)
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.