Steel 12CrMo9-10
EN 12CrMo9-10 · ASTM A335 P22
12CrMo9-10 (1.7375, A335 P22) is a 2.25 % Cr–1 % Mo creep-resistant alloy steel supplied as tube, pipe, plate and bar in +NT, +A, +N, +QT, hot-rolled and cold-drawn conditions.
Reference datasheet — 12CrMo9-10 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the +NT condition
12CrMo9-10 tempers and conditions
12CrMo9-10 is supplied in 6 conditions, soft to hard. +NT is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Pick for maximum machinability/cold-forming of tube and bar before final normalize-and-temper of the fabricated part. | 250 | 470 | 28 | 140 HB | 7.9 % IACS |
+NTDefault Normalized and tempered | Standard delivery condition for EN 10216-2 seamless tube and EN 10028-2 plate; best balance of creep strength and toughness for steam service. | 320 | 540 | 24 | 160 HB | — |
Hot rolled | Mill as-rolled semi-finished stock bought for re-forging or for parts that will be fully heat treated after machining. | 340 | 570 | 20 | 175 HB | 7.8 % IACS |
Normalized | Intermediate condition for plate/pipe that will still see PWHT or a subsequent temper; slightly higher strength but lower toughness than +NT. | 370 | 590 | 21 | 180 HB | 7.8 % IACS |
Quenched and tempered | Used for heavy forgings, valve bodies and thick-wall vessel shells (EN 10222-2 / EN 10250-2) where through-thickness strength and toughness are needed. | 400 | 610 | 20 | 12 HRC | — |
Cold drawn | Small-diameter precision tube and bar; higher strength and tight tolerance, but requires stress-relief/normalize-temper before high-temperature service. | 500 | 640 | 14 | 205 HB | 7.7 % IACS |
What is 12CrMo9-10?
12CrMo9-10 (1.7375, A335 P22) is a 2.25 % Cr–1 % Mo creep-resistant alloy steel supplied as tube, pipe, plate and bar in +NT, +A, +N, +QT, hot-rolled and cold-drawn conditions. It is chosen for boiler and steam-piping pressure parts operating to about 565 °C, with 320 MPa yield, 540 MPa tensile and 24 % elongation at roughly 160 HB. Welding is workable (score 55) but needs preheat, low-hydrogen practice and mandatory PWHT, and the steel has no ambient corrosion resistance — bare surfaces scale above ~570 °C. Where higher creep strength is required, 7CrMoVTiB10-10 (T24) or 9 % Cr grades such as X11CrMo9-1 are the next options. 12CrMo9-10 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,490°C (2,714 °F). 12CrMo9-10 has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 540 MPa (78.3 ksi) — weaker than 81% of steel grades. Elongation at break is 24% and the elastic modulus is 210 GPa (30.5 Msi).
What is 12CrMo9-10 used for?
- boiler tubes
- steam piping
- pressure vessels
Advantages
- High service temperature — 565°C (1,049 °F), better than 96% of steel grades
- Tough — resists crack growth — 130 MPa·√m (118.3 ksi·√in), better than 89% of steel grades
Limitations
- Low strength — 320 MPa (46.4 ksi), worse than 81% of steel grades
12CrMo9-10 properties
Typical room-temperature values for 12CrMo9-10-+NT; bars are the position among steel grades.
Physical3
12CrMo9-10 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,490°C (2,714 °F).
Mechanical16
12CrMo9-10 has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 540 MPa (78.3 ksi) — weaker than 81% of steel grades. Elongation at break is 24% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
12CrMo9-10 is rated for continuous service to 565°C (1,049 °F). It conducts heat at 37 W/m·K (21.4 BTU/hr·ft·°F), worse than 71% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
12CrMo9-10 conducts electricity at 7.8 % IACS, worse than 57% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (20/100), better than 87% of steel grades.
Sustainability4
Producing a kilogram of 12CrMo9-10 takes about 32 MJ of energy and emits 2.2 kg of CO₂ — more than 70% of steel grades. Typical recycled content is 25%.
Manufacturability8
12CrMo9-10's machinability is good (55/100, better than 62% of steel grades); weldability good (55/100); formability good (55/100).
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. 12CrMo9-10 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 12CrMo9-10
Is 12CrMo9-10 easy to machine?
Machines like annealed 4130 at ~60 % of 1212 — moderate speeds, rigid setups, positive-rake carbide and generous coolant to avoid work hardening and gummy chips.
Can 12CrMo9-10 be welded?
Weld with matching 2.25Cr-1Mo consumables (E9018-B3 / ER90S-B3), preheat 200–250 °C, interpass ≤350 °C, low-hydrogen practice, and mandatory PWHT 690–730 °C; hold hardness ≤225 HB in wet-H2S service.
Can 12CrMo9-10 be formed, bent or molded?
Hot bend/form at 900–1050 °C followed by normalize-and-temper; cold bending of tube is possible with generous radii but needs stress relief before high-temperature service.
12CrMo9-10 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 | 0.08 – 0.15 | 0.12 |
| Si | ≤ 0.5 | 0.25 |
| MnEN 10216-2 range; A335 P22 0.30–0.60 | 0.4 – 0.8 | 0.55 |
| P | ≤ 0.02 | 0.01 |
| S | ≤ 0.01 | 0.01 |
| Cr | 2 – 2.5 | 2.25 |
| Mo | 0.9 – 1.1 | 1 |
| Niresidual | ≤ 0.3 | |
| Fe | balance |
What surface finishes work on 12CrMo9-10?
Not anodizable; protect with phosphate + high-temperature aluminium/silicone paint, aluminizing or thermal insulation — bare surfaces scale above ~570 °C and rust in humid 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).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel 12CrMo9-10 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- A335 P22
- EN / DIN / Werkstoff-Nr.
- 1.7375
How much does 12CrMo9-10 cost?
12CrMo9-10 is a standard-cost steel ($$), cheaper than about 71% 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.
12CrMo9-10 — frequently asked
What is 12CrMo9-10 used for?
12CrMo9-10 is typically used for boiler tubes, steam piping and pressure vessels. In short: workhorse P22 pipe steel; 565 °C creep service; weldable with PWHT.
What is the yield strength of 12CrMo9-10?
12CrMo9-10 has a typical yield strength of 320 MPa (46.4 ksi) and a tensile strength of 540 MPa (78.3 ksi) — weaker than 81% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is 12CrMo9-10 easy to machine?
Reasonably — machinability is rated good (55/100, better than 62% of steel grades). Machines like annealed 4130 at ~60 % of 1212 — moderate speeds, rigid setups, positive-rake carbide and generous coolant to avoid work hardening and gummy chips.
Can 12CrMo9-10 be welded?
Yes — weldability is rated good (55/100). Weld with matching 2.25Cr-1Mo consumables (E9018-B3 / ER90S-B3), preheat 200–250 °C, interpass ≤350 °C, low-hydrogen practice, and mandatory PWHT 690–730 °C; hold hardness ≤225 HB in wet-H2S service.
What surface finishes work on 12CrMo9-10?
Not anodizable; protect with phosphate + high-temperature aluminium/silicone paint, aluminizing or thermal insulation — bare surfaces scale above ~570 °C and rust in humid storage.
Can 12CrMo9-10 be formed, bent or molded?
Hot bend/form at 900–1050 °C followed by normalize-and-temper; cold bending of tube is possible with generous radii but needs stress relief before high-temperature service.
What is the maximum service temperature of 12CrMo9-10?
12CrMo9-10 is rated for continuous use to about 565°C (1,049 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 12CrMo9-10 +NT and 12CrMo9-10-CD?
+NT is the default condition — standard delivery condition for EN 10216-2 seamless tube and EN 10028-2 plate; best balance of creep strength and toughness for steam service. CD: small-diameter precision tube and bar; higher strength and tight tolerance, but requires stress-relief/normalize-temper before high-temperature service. Yield strength is 320 MPa in +NT versus 500 MPa in CD.
How much does 12CrMo9-10 cost?
12CrMo9-10 is a standard-cost steel ($$), cheaper than about 71% 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.
Sources
- EN 10216-2 Seamless steel tubes for pressure purposes — alloy steel with specified elevated temperature properties — CEN (2020)
- EN 10028-2 Flat products for pressure purposes — alloy steels with specified elevated temperature properties — CEN (2017)
- EN 10222-2 Steel forgings for pressure purposes — ferritic and martensitic steels — CEN (2021)
- ASTM A335/A335M Seamless Ferritic Alloy-Steel Pipe for High-Temperature Service (Grade P22) — ASTM (2023)
- GB/T 5310 (12Cr2MoG) — SAC (2017)
- ASME BPVC Section II Part D — Material Properties (2.25Cr-1Mo) — ASME (2023)
- ASM Handbook Vol.1 Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- API RP 941 Steels for Hydrogen Service at Elevated Temperatures — API (2016)
- Seamless Cr-Mo boiler tube datasheets (P22 / 10CrMo910) — Vallourec / Sandvik (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.