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Steel 25CrMo4 vs 40Cr

Steel · grade comparison

Steel 25CrMo4 and 40Cr are both steel grades, both alloy steel. 25CrMo4 is the stronger of the two: yield strength 650 MPa (94.3 ksi) against 430 MPa (62.4 ksi) for 40Cr, about 51% more; tensile strength follows at 870 MPa (126 ksi) vs 720 MPa (104 ksi). 25CrMo4 is harder — 270 HB against 210 HB for 40Cr — which matters for wear surfaces and threads. 25CrMo4 runs hotter in service (500°C vs 400°C continuous). On the shop floor, 25CrMo4 welds better (good vs fair).

25CrMo4Choose it when strength drives the design, or when surface hardness matters.

25CrMo4 vs 40Cr: properties

25CrMo440Cr

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

210 GPa30.5 Msi
211 GPa30.6 Msi

Shear Modulus

80 GPa11.6 Msi
81 GPa11.7 Msi

Tensile Strength (Ultimate)

870 MPa126 ksi
720 MPa104 ksi

Yield Strength (0.2% offset)

650 MPa94.3 ksi
430 MPa62.4 ksi

Reduction in Area

50%
45%

Compressive Strength

660 MPa95.7 ksi
430 MPa62.4 ksi

Shear Strength

520 MPa75.4 ksi
430 MPa62.4 ksi

Fatigue Strength (Endurance Limit)

450 MPa65.3 ksi
330 MPa47.9 ksi

Fracture Toughness (K_IC)

90 MPa·√m81.9 ksi·√in
55 MPa·√m50.1 ksi·√in

Charpy V-Notch Impact (RT)

60 J44.3 ft·lbf
40 J29.5 ft·lbf

Hardness, Brinell

270 HB
210 HB

Hardness, Rockwell C

28 HRC
16 HRC

Hardness, Vickers

285 HV
—

Hardness, Rockwell B

—
94 HRB

Same in both: Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Elongation at Break 16%

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,420°C2,588 °F
1,425°C2,597 °F

Liquidus Temperature

1,500°C2,732 °F
1,495°C2,723 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

42 W/m·K24.3 BTU/hr·ft·°F
44 W/m·K25.4 BTU/hr·ft·°F

Specific Heat Capacity

460 J/kg·K0.11 BTU/lb·°F
470 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

12.3 µm/m·K6.8 µin/in·°F
12.5 µm/m·K6.9 µin/in·°F

Max Service Temperature (continuous)

500°C932 °F
400°C752 °F

Min Service Temperature

-40°C-40 °F
-30°C-22 °F

Same in both: Latent Heat of Fusion 250 J/g107 BTU/lb

Electrical

Conductivity and insulation.

Electrical Conductivity

7.8 % IACS
8 % IACS

Same in both: Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.6 V
-0.61 V

Corrosion Resistance

13 / 100
12 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Weldability

65 / 100
45 / 100

Formability (cold)

45 / 100
40 / 100

Brazeability / Solderability

60 / 100
55 / 100

Polishability

65 / 100
60 / 100

Same in both: Machinability 55 / 100 · Machinability Rating (AISI 1212 = 100 %) 60%

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

31 MJ/kg13,328 BTU/lb
26 MJ/kg11,178 BTU/lb

Embodied Carbon (primary production)

2.2 kg CO₂/kg
2 kg CO₂/kg

Typical Recycled Content

30%
35%

Same in both: Embodied Water 60 L/kg7.2 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

111 kN·m/kg
92 kN·m/kg

Specific Stiffness (E / density)

26.8 MN·m/kg
26.9 MN·m/kg

Modulus of Resilience

1,006 kJ/m³
438 kJ/m³

Thermal Diffusivity

11.6 mm²/s
11.9 mm²/s

Thermal Shock Resistance Index

14
12

Strength versus weight

Yield strength against density for every steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scale40Cr25CrMo4

Manufacturing and finishing

Capability25CrMo440Cr
Default conditionQ&THR
Relative cost$$ Standard$$ Standard
Min. machined wall0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 1.6 µm

Both are offered for CNC machining and Sheet metal. Both take the same 38 finishes: AlCrN, AlTiN, Black Oxide, CVD Al2O3, CVD TiCN, CVD TiN, Cerakote, Chrome Plating, Copper Plating, CrN, DLC, E-Coating and 26 more.

25CrMo4 vs 40Cr — frequently asked

Is 25CrMo4 stronger than 40Cr?

Yes. 25CrMo4 has a typical yield strength of 650 MPa (94.3 ksi) against 430 MPa (62.4 ksi) for 40Cr — about 51% more. Tensile strength is 870 MPa (126 ksi) vs 720 MPa (104 ksi).

Which is cheaper, 25CrMo4 or 40Cr?

Both sit in the same relative cost tier ($$, standard); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which welds better, 25CrMo4 or 40Cr?

25CrMo4. Its weldability rates good (65/100) against fair (45/100) for 40Cr.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 25CrMo4 and 40Cr side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.

Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.