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Steel 25CrMo4 vs 42CrMo4

Steel · grade comparison

Steel 25CrMo4 and 42CrMo4 are both steel grades. 25CrMo4 is the stronger of the two: yield strength 650 MPa (94.3 ksi) against 550 MPa (79.8 ksi) for 42CrMo4, about 18% more. 25CrMo4 is the more ductile: elongation 16% versus 14% for 42CrMo4, and 25CrMo4 is harder (270 HB vs 245 HB). 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 the part is bent, formed or impact-loaded.

25CrMo4 vs 42CrMo4: properties

25CrMo442CrMo4

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

870 MPa126 ksi
850 MPa123 ksi

Yield Strength (0.2% offset)

650 MPa94.3 ksi
550 MPa79.8 ksi

Elongation at Break

16%
14%

Reduction in Area

50%
40%

Compressive Strength

660 MPa95.7 ksi
560 MPa81.2 ksi

Shear Strength

520 MPa75.4 ksi
510 MPa74 ksi

Fatigue Strength (Endurance Limit)

450 MPa65.3 ksi
400 MPa58 ksi

Fracture Toughness (K_IC)

90 MPa·√m81.9 ksi·√in
75 MPa·√m68.3 ksi·√in

Charpy V-Notch Impact (RT)

60 J44.3 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

270 HB
245 HB

Hardness, Rockwell C

28 HRC
23 HRC

Hardness, Vickers

285 HV
258 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Liquidus Temperature

1,500°C2,732 °F
1,495°C2,723 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F

Thermal

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

Thermal Conductivity

42 W/m·K24.3 BTU/hr·ft·°F
42.6 W/m·K24.6 BTU/hr·ft·°F

Specific Heat Capacity

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

Max Service Temperature (continuous)

500°C932 °F
400°C752 °F

Same in both: Thermal Expansion (CTE, 20–100 °C) 12.3 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 7.8 % IACS · Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

13 / 100
12 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V

Manufacturability

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

Machinability

55 / 100
50 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
55%

Weldability

65 / 100
35 / 100

Formability (cold)

45 / 100
35 / 100

Brazeability / Solderability

60 / 100
50 / 100

Polishability

65 / 100
70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

31 MJ/kg13,328 BTU/lb
30 MJ/kg12,898 BTU/lb

Same in both: Embodied Carbon (primary production) 2.2 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb · Typical Recycled Content 30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

111 kN·m/kg
108 kN·m/kg

Modulus of Resilience

1,006 kJ/m³
720 kJ/m³

Thermal Diffusivity

11.6 mm²/s
11.5 mm²/s

Same in both: Specific Stiffness (E / density) 26.8 MN·m/kg · Thermal Shock Resistance Index 14

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 scale42CrMo425CrMo4

Manufacturing and finishing

Capability25CrMo442CrMo4
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 42CrMo4 — frequently asked

Is 25CrMo4 stronger than 42CrMo4?

Yes. 25CrMo4 has a typical yield strength of 650 MPa (94.3 ksi) against 550 MPa (79.8 ksi) for 42CrMo4 — about 18% more. Tensile strength is 870 MPa (126 ksi) vs 850 MPa (123 ksi).

Which is cheaper, 25CrMo4 or 42CrMo4?

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 is easier to machine, 25CrMo4 or 42CrMo4?

25CrMo4. Its machinability rates good (55/100) against fair (50/100) for 42CrMo4; for welding the order is 25CrMo4 first (good, 65/100) then 42CrMo4 (fair, 35/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 25CrMo4 and 42CrMo4 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.