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Steel 28NiCrMoV8-5 vs 42CrMo4

Steel · grade comparison

Steel 28NiCrMoV8-5 and 42CrMo4 are both steel grades. 28NiCrMoV8-5 is the stronger of the two: yield strength 720 MPa (104 ksi) against 550 MPa (79.8 ksi) for 42CrMo4, about 31% more. 28NiCrMoV8-5 is the more ductile: elongation 16% versus 14% for 42CrMo4, and 28NiCrMoV8-5 is harder (270 HB vs 245 HB). 42CrMo4 conducts heat better (42.6 W/m·K vs 36 W/m·K).

28NiCrMoV8-5Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

28NiCrMoV8-5 vs 42CrMo4: properties

28NiCrMoV8-542CrMo4

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Shear Modulus

81 GPa11.7 Msi
80 GPa11.6 Msi

Bulk Modulus

165 GPa23.9 Msi
160 GPa23.2 Msi

Tensile Strength (Ultimate)

880 MPa128 ksi
850 MPa123 ksi

Yield Strength (0.2% offset)

720 MPa104 ksi
550 MPa79.8 ksi

Elongation at Break

16%
14%

Reduction in Area

52%
40%

Compressive Strength

730 MPa106 ksi
560 MPa81.2 ksi

Shear Strength

540 MPa78.3 ksi
510 MPa74 ksi

Fatigue Strength (Endurance Limit)

420 MPa60.9 ksi
400 MPa58 ksi

Fracture Toughness (K_IC)

130 MPa·√m118 ksi·√in
75 MPa·√m68.3 ksi·√in

Charpy V-Notch Impact (RT)

70 J51.6 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

270 HB
245 HB

Hardness, Rockwell C

27 HRC
23 HRC

Hardness, Vickers

285 HV
258 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Density

7.83 g/cm³0.28 lb/in³
7.85 g/cm³0.28 lb/in³

Liquidus Temperature

1,490°C2,714 °F
1,495°C2,723 °F

Same in both: Melting Point (Solidus) 1,420°C2,588 °F

Thermal

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

Thermal Conductivity

36 W/m·K20.8 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

Latent Heat of Fusion

270 J/g116 BTU/lb
250 J/g107 BTU/lb

Min Service Temperature

-30°C-22 °F
-40°C-40 °F

Same in both: Thermal Expansion (CTE, 20–100 °C) 12.3 µm/m·K6.8 µin/in·°F · Max Service Temperature (continuous) 400°C752 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

7.5 % IACS
7.8 % IACS

Electrical Resistivity

2.3×10⁻⁷ Ω·m9.06 µΩ·in
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

45 / 100
50 / 100

Machinability Rating (AISI 1212 = 100 %)

50%
55%

Weldability

30 / 100
35 / 100

Formability (cold)

20 / 100
35 / 100

Brazeability / Solderability

40 / 100
50 / 100

Same in both: Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

34 MJ/kg14,617 BTU/lb
30 MJ/kg12,898 BTU/lb

Embodied Carbon (primary production)

2.4 kg CO₂/kg
2.2 kg CO₂/kg

Typical Recycled Content

25%
30%

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

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

112 kN·m/kg
108 kN·m/kg

Modulus of Resilience

1,234 kJ/m³
720 kJ/m³

Thermal Diffusivity

10 mm²/s
11.5 mm²/s

Thermal Shock Resistance Index

12
14

Same in both: Specific Stiffness (E / density) 26.8 MN·m/kg

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 scale42CrMo428NiCrMoV8-5

Manufacturing and finishing

Capability28NiCrMoV8-542CrMo4
CNC machining—Yes
Sheet metal—Yes
Default condition—HR
Relative cost$$ Standard$$ Standard
Min. machined wall—0.8 mm
Best machined surface—Ra 1.6 µm
AlCrN—Yes
AlTiN—Yes
Black Oxide—Yes
CVD Al2O3—Yes
CVD TiCN—Yes
CVD TiN—Yes
Cerakote—Yes
Chrome Plating—Yes
CrN—Yes
DLC—Yes
E-Coating—Yes
HVOF Coating—Yes
Hot-Dip Galvanizing—Yes
MoS2—Yes
Multilayer CVD—Yes
Nickel Plating—Yes
PTFE Coating—Yes
Painting—Yes

They share 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

28NiCrMoV8-5 vs 42CrMo4 — frequently asked

Is 28NiCrMoV8-5 stronger than 42CrMo4?

Yes. 28NiCrMoV8-5 has a typical yield strength of 720 MPa (104 ksi) against 550 MPa (79.8 ksi) for 42CrMo4 — about 31% more. Tensile strength is 880 MPa (128 ksi) vs 850 MPa (123 ksi).

Which is cheaper, 28NiCrMoV8-5 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, 28NiCrMoV8-5 or 42CrMo4?

42CrMo4, by a small margin. Both rate fair for machinability — 50/100 against 45/100 for 28NiCrMoV8-5; for welding the order is 42CrMo4 first (fair, 35/100) then 28NiCrMoV8-5 (poor, 30/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 28NiCrMoV8-5 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.