Steel 25Cr2MoVA
GB 25Cr2MoVA
25Cr2MoVA is a Cr-Mo-V low-alloy quenched-and-tempered steel to GB/T 3077, in which molybdenum plus vanadium give high tempering stability, relaxation resistance and elevated-temperature strength.
Values for the Q&T condition
25Cr2MoVA tempers and conditions
25Cr2MoVA is supplied in 8 conditions, soft to hard. Q&T is the default FabDigit quotes; the values on this page are for it.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Softest condition for rough machining, deep-hole drilling and thread rolling before final Q&T. | 450 | 720 | 22 | 18 HRC | 8 % IACS |
Hot rolled | Mill supply condition for bar to be re-heat-treated by the part maker; not for load-bearing use as-is. | 520 | 800 | 15 | 25 HRC | 7.8 % IACS |
Normalized | Grain refinement and structure homogenisation of forgings before final quench and temper. | 620 | 880 | 16 | 27 HRC | 7.6 % IACS |
Cold drawn | Close-tolerance, bright-finish bar for small shafts and stems where full Q&T strength is not needed. | 700 | 850 | 12 | 26 HRC | 7.7 % IACS |
Bolting temper | Hardness-controlled temper for pressure-boundary studs where relaxation resistance and toughness matter more than peak strength. | 800 | 950 | 18 | 30 HRC | — |
Q&TDefault Quenched and tempered | Standard delivered condition for high-temperature bolting, studs and valve spindles; meets GB/T 3077 property table. | 850 | 1,000 | 16 | 31 HRC | — |
quenched & tempered then gas/ion nitrided | Choose for valve spindles, gears and wear surfaces needing a hard, seizure-resistant case on a tough 30 HRC core. | 850 | 1,000 | 14 | 31 HRC | 7.5 % IACS |
Higher-strength temper | Pick when maximum bolt preload or shaft strength is wanted and service temperature stays below ~450 °C. | 1,000 | 1,150 | 13 | 36 HRC | — |
What is 25Cr2MoVA?
25Cr2MoVA is a Cr-Mo-V low-alloy quenched-and-tempered steel to GB/T 3077, in which molybdenum plus vanadium give high tempering stability, relaxation resistance and elevated-temperature strength. It is used for steam turbine and high-pressure valve duty — high-temperature bolting, studs, valve stems and nitrided parts — with Q&T tensile strength typically 930–1080 MPa and low preload relaxation in 500–540 °C service. Hardenability is good but weldability is poor, corrosion resistance is no better than plain low-alloy steel, and heavy sections are sensitive to temper embrittlement and hydrogen-induced delayed fracture. 25Cr2MoVA 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). 25Cr2MoVA has a yield strength of 850 MPa (123 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 88% of steel grades. Elongation at break is 16% and the elastic modulus is 210 GPa (30.5 Msi).
What is 25Cr2MoVA used for?
- Steam turbine bolting and studs
- High-pressure valve stems
- High-temperature flange fasteners
- Nitrided shafts and spindles
- Boiler superheater components
- Hot petrochemical piping fittings
- Pressure-vessel internal fasteners
Advantages
- High service temperature — 520°C (968 °F), better than 92% of steel grades
- High strength — 850 MPa (123 ksi), better than 88% of steel grades
25Cr2MoVA properties
Typical room-temperature values for 25Cr2MoVA-Q&T; bars are the position among steel grades.
Physical3
25Cr2MoVA 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
25Cr2MoVA has a yield strength of 850 MPa (123 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 88% of steel grades. Elongation at break is 16% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
25Cr2MoVA is rated for continuous service to 520°C (968 °F). It conducts heat at 38 W/m·K (22 BTU/hr·ft·°F), worse than 69% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).
Electrical3
25Cr2MoVA conducts electricity at 7.5 % IACS, worse than 67% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (15/100), better than 75% of steel grades.
Sustainability4
Producing a kilogram of 25Cr2MoVA takes about 34 MJ of energy and emits 2.4 kg of CO₂ — more than 82% of steel grades. Typical recycled content is 30%.
Manufacturability8
25Cr2MoVA's machinability is fair (42/100, worse than 73% of steel grades); weldability poor (32/100); formability poor (25/100).
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. 25Cr2MoVA is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 25Cr2MoVA
Is 25Cr2MoVA easy to machine?
Rough machine annealed (≤241 HB) and finish after Q&T at 28–35 HRC with coated carbide, rigid setups and moderate speeds; thread rolling before tempering gives the best fatigue life.
Can 25Cr2MoVA be welded?
Weld only when unavoidable — preheat 250–350 °C, use matched Cr-Mo-V or 2.25Cr-1Mo filler, low hydrogen, and PWHT/temper at 680–700 °C to avoid cold cracking.
Can 25Cr2MoVA be formed, bent or molded?
Forge 1150→850 °C with slow cooling then anneal; cold bending is impractical in the Q&T state.
Manufacturability
The process limits FabDigit applies to 25Cr2MoVA. Every 25Cr2MoVA part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Fair42 / 100 |
|---|---|
| ISO material group | P.2 |
| Cutting speed (rough / finish) | 180 / 210 m/min |
| Minimum wall | 0.8 mm |
| Minimum internal radius | 1 mm |
| Drill depth limit | 5× diameter |
| Best surface (machined / polished) | Ra 1.6 / — |
| Hardenable after machining | No |
Sheet metal
| Formability | Fair25 / 100 |
|---|---|
| Weldability | Better32 / 100 |
25Cr2MoVA 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 | 0.22 – 0.29 | 0.26 |
| Si | 0.17 – 0.37 | 0.27 |
| Mn | 0.4 – 0.7 | 0.55 |
| Cr | 1.5 – 1.8 | 1.65 |
| Mo | 0.25 – 0.35 | 0.3 |
| V | 0.15 – 0.3 | 0.22 |
| Niresidual | ≤ 0.3 | |
| Curesidual | ≤ 0.2 | |
| Phigh-quality steel grade A limit | ≤ 0.03 | |
| Shigh-quality steel grade A limit | ≤ 0.03 | |
| Fe | balance |
What surface finishes work on 25Cr2MoVA?
Phosphate, black oxide or Zn-Ni/aluminium-flake coatings for atmospheric use; gas or ion nitriding at 520–560 °C gives an 800–1000 HV case — avoid electroplating above 1000 MPa without hydrogen bake-out.
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).
Plating
CVD Coating
Black / Phosphate
Thermal Spray
How much does 25Cr2MoVA cost?
25Cr2MoVA 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.
25Cr2MoVA — frequently asked
What is 25Cr2MoVA used for?
25Cr2MoVA is typically used for steam turbine bolting and studs, high-pressure valve stems, high-temperature flange fasteners, nitrided shafts and spindles, boiler superheater components and hot petrochemical piping fittings. In short: high-strength aerospace bar.
What is the yield strength of 25Cr2MoVA?
25Cr2MoVA has a typical yield strength of 850 MPa (123 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 88% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is 25Cr2MoVA easy to machine?
Not especially — machinability is rated fair (42/100, worse than 73% of steel grades). Rough machine annealed (≤241 HB) and finish after Q&T at 28–35 HRC with coated carbide, rigid setups and moderate speeds; thread rolling before tempering gives the best fatigue life.
Can 25Cr2MoVA be welded?
Not readily — weldability is rated poor (32/100). Weld only when unavoidable — preheat 250–350 °C, use matched Cr-Mo-V or 2.25Cr-1Mo filler, low hydrogen, and PWHT/temper at 680–700 °C to avoid cold cracking.
What surface finishes work on 25Cr2MoVA?
Phosphate, black oxide or Zn-Ni/aluminium-flake coatings for atmospheric use; gas or ion nitriding at 520–560 °C gives an 800–1000 HV case — avoid electroplating above 1000 MPa without hydrogen bake-out.
Can 25Cr2MoVA be formed, bent or molded?
Forge 1150→850 °C with slow cooling then anneal; cold bending is impractical in the Q&T state.
What is the maximum service temperature of 25Cr2MoVA?
25Cr2MoVA is rated for continuous use to about 520°C (968 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 25Cr2MoVA Q&T and 25Cr2MoVA-A?
Q&T is the default condition — standard delivered condition for high-temperature bolting, studs and valve spindles; meets GB/T 3077 property table. A: softest condition for rough machining, deep-hole drilling and thread rolling before final Q&T. Yield strength is 850 MPa in Q&T versus 450 MPa in A.
How much does 25Cr2MoVA cost?
25Cr2MoVA 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.
Can FabDigit make parts in 25Cr2MoVA?
Yes — 25Cr2MoVA is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- ASM Handbook Vol. 1: Properties and Selection — Irons, Steels and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol. 19: Fatigue and Fracture — ASM International (1996)
- ASTM A193/A193M (B16 Cr-Mo-V bolting, comparison grade) — ASTM International (2023)
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.