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Steel 25CrMo4 · hardness band

Steel 25CrMo4 Q&T 28-32 HRC

Properties of the Q&T 28-32 HRC condition, compared with the other 25CrMo4 tempers.

Pick when drawings call out a hardness band (shafts, sprockets, sour-service-adjacent pressure parts limited to ≤ 32 HRC).

CNC machiningSheet metalStandard cost $$

What is 25CrMo4 Q&T 28-32 HRC?

25CrMo4 Q&T 28-32 HRC is 25CrMo4 heat treated to Q&T 28-32 HRC — pick when drawings call out a hardness band (shafts, sprockets, sour-service-adjacent pressure parts limited to ≤ 32 HRC). 25CrMo4 Q&T 28-32 HRC has a yield strength of 800 MPa (116 ksi) and a tensile strength of 950 MPa (138 ksi) — stronger than 86% of steel grades. Elongation at break is 15% and the elastic modulus is 210 GPa (30.5 Msi). 25CrMo4 Q&T 28-32 HRC 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). Q&T is the default condition FabDigit quotes; Q&T 28-32 HRC is available on request or by drawing note.

Advantages

  • High service temperature — 500°C (932 °F), better than 90% of steel grades
  • High strength — 800 MPa (116 ksi), better than 86% of steel grades
  • Polishes to a fine finish — 65/100, better than 78% of steel grades

25CrMo4 Q&T 28-32 HRC properties

Typical room-temperature values for 25CrMo4 Q&T 28-32 HRC — 11 properties are specific to this condition; the rest are grade-level values shared by every 25CrMo4 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.

Physical3

25CrMo4 Q&T 28-32 HRC 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).

Density7.85 g/cm³0.28 lb/in³
Melting Point (Solidus)1,420°C2,588 °F
Liquidus Temperature1,500°C2,732 °F

Mechanical16

25CrMo4 Q&T 28-32 HRC has a yield strength of 800 MPa (116 ksi) and a tensile strength of 950 MPa (138 ksi) — stronger than 86% of steel grades. Elongation at break is 15% and the elastic modulus is 210 GPa (30.5 Msi).

Elastic (Young's) Modulus210 GPa30.5 Msi
Shear Modulus80 GPa11.6 Msi
Bulk Modulus160 GPa23.2 Msi
Poisson's Ratio0.29
Tensile Strength (Ultimate)950 MPa138 ksi
Yield Strength (0.2% offset)800 MPa116 ksi
Elongation at Break15%
Reduction in Area48%
Compressive Strength660 MPa95.7 ksi
Shear Strength520 MPa75.4 ksi
Fatigue Strength (Endurance Limit)480 MPa69.6 ksi
Fracture Toughness (K_IC)90 MPa·√m81.9 ksi·√in
Charpy V-Notch Impact (RT)55 J40.6 ft·lbf
Hardness, Brinell290 HB
Hardness, Rockwell C30 HRC
Hardness, Vickers305 HV

Thermal6

25CrMo4 Q&T 28-32 HRC is rated for continuous service to 500°C (932 °F). It conducts heat at 42 W/m·K (24.3 BTU/hr·ft·°F), worse than 56% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).

Thermal Conductivity42 W/m·K24.3 BTU/hr·ft·°F
Specific Heat Capacity460 J/kg·K0.11 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)12.3 µm/m·K6.8 µin/in·°F
Latent Heat of Fusion250 J/g107 BTU/lb
Max Service Temperature (continuous)500°C932 °F
Min Service Temperature-40°C-40 °F

Electrical3

25CrMo4 Q&T 28-32 HRC conducts electricity at 7.8 % IACS, worse than 58% of steel grades.

Electrical Conductivity7.8 % IACS
Electrical Resistivity2.2×10⁻⁷ Ω·m8.66 µΩ·in
Magnetic Responseferromagnetic

Chemical & Environmental3

Corrosion resistance is not recommended (13/100), better than 66% of steel grades.

Galvanic Potential (seawater, vs SCE)-0.6 V
Corrosion ResistanceNot recommended13/100
Chemical Resistance SummaryRusts in humid air and water; attacked by acids and chlorides. Resists dry hydrocarbons, oils and hydrogen at moderate temperature (Cr-Mo helps against hydrogen attack); requires paint, phosphate, zinc or Cd/Ni plating in service.

Sustainability4

Producing a kilogram of 25CrMo4 Q&T 28-32 HRC takes about 31 MJ of energy and emits 2.2 kg of CO₂ — more than 64% of steel grades. Typical recycled content is 30%.

Embodied Energy (primary production)31 MJ/kg13,328 BTU/lb
Embodied Carbon (primary production)2.2 kg CO₂/kg
Embodied Water60 L/kg7.2 gal/lb
Typical Recycled Content30%

Manufacturability6

25CrMo4 Q&T 28-32 HRC's machinability is fair (50/100, worse than 53% of steel grades); weldability good (65/100); formability fair (45/100).

MachinabilityFair50/100
Machinability Rating (AISI 1212 = 100 %)55%
WeldabilityGood65/100
Formability (cold)Fair45/100
Brazeability / SolderabilityGood60/100
PolishabilityGood65/100

Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.

Other 25CrMo4 tempers and conditions

25CrMo4 is also supplied in 10 other conditions. The full side-by-side table is on the 25CrMo4 overview.

Working with 25CrMo4 Q&T 28-32 HRC

Is 25CrMo4 easy to machine?

Machines like 4130: carbide at 100–160 m/min in Q&T state, rigid setups and positive rake; annealed bar cuts about 70 % of 1212.

Can 25CrMo4 be welded?

Good weldability with low-hydrogen filler (ER80S-D2 / E8018-B2); preheat 150–250 °C on sections above ~10 mm and stress-relieve or re-normalize thick weldments.

Can 25CrMo4 be formed, bent or molded?

Cold bend and roll in +A/+N condition only (generous radii); hot work 850–1100 °C then normalize or re-quench and temper.

What surface finishes work on 25CrMo4?

No inherent corrosion protection — phosphate + paint, zinc or Ni/Cd plating usual; bake after plating to avoid hydrogen embrittlement above ~1000 MPa; polishes to a bright finish.

25CrMo4 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.

ElementSpec limit (wt %)Nominal
C0.22 – 0.290.25
Si≤ 0.40.25
Mn0.6 – 0.90.75
Cr0.9 – 1.21.05
Mo0.15 – 0.30.22
P0.035 max for some product forms≤ 0.03
S+S variant 0.020–0.040 for machinability≤ 0.04
Febalance

25CrMo4 Q&T 28-32 HRC — frequently asked

What is 25CrMo4 Q&T 28-32 HRC used for?

25CrMo4 Q&T 28-32 HRC is typically used for bolts and high-tensile fasteners, industrial drive shafts, welded tubular frames and structures, hydraulic cylinder components, gear and sprocket blanks and pressure-retaining machined fittings. In short: premium Cr-Mo bar.

What is the yield strength of 25CrMo4 Q&T 28-32 HRC?

25CrMo4 Q&T 28-32 HRC has a typical yield strength of 800 MPa (116 ksi) and a tensile strength of 950 MPa (138 ksi) — stronger than 86% of steel grades. Strength varies by condition: see the 11 listed tempers.

Is 25CrMo4 Q&T 28-32 HRC easy to machine?

Reasonably — machinability is rated fair (50/100, worse than 53% of steel grades). Machines like 4130: carbide at 100–160 m/min in Q&T state, rigid setups and positive rake; annealed bar cuts about 70 % of 1212.

Can 25CrMo4 Q&T 28-32 HRC be welded?

Yes — weldability is rated good (65/100). Good weldability with low-hydrogen filler (ER80S-D2 / E8018-B2); preheat 150–250 °C on sections above ~10 mm and stress-relieve or re-normalize thick weldments.

What surface finishes work on 25CrMo4 Q&T 28-32 HRC?

No inherent corrosion protection — phosphate + paint, zinc or Ni/Cd plating usual; bake after plating to avoid hydrogen embrittlement above ~1000 MPa; polishes to a bright finish.

Can 25CrMo4 Q&T 28-32 HRC be formed, bent or molded?

Cold bend and roll in +A/+N condition only (generous radii); hot work 850–1100 °C then normalize or re-quench and temper.

What is the maximum service temperature of 25CrMo4 Q&T 28-32 HRC?

25CrMo4 Q&T 28-32 HRC 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.

Can FabDigit make parts in 25CrMo4 Q&T 28-32 HRC?

Yes — 25CrMo4 Q&T 28-32 HRC is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.

Sources

  1. EN 10083-3 Steels for quenching and tempering — alloy steelsCEN (2006)
  2. EN 10297-1 / EN 10305-1 seamless steel tubes (25CrMo4)CEN (2016)
  3. GB/T 3077 (25CrMo)SAC (2015)
  4. ASM Handbook Vol.1 — Properties and Selection: Irons, SteelsASM International (1990)
  5. MMPDS-15 (AISI 4130 mechanical property tables)Battelle/FAA (2020)
  6. 1.7218 / 25CrMo4 alloy steel datasheetBöhler / Ovako (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.