FabDigitFabDigit

Steel 20CrMoV5-7 vs 42CrMo4

Steel · grade comparison

Steel 20CrMoV5-7 and 42CrMo4 are both steel grades. 20CrMoV5-7 is the stronger of the two: yield strength 700 MPa (102 ksi) against 550 MPa (79.8 ksi) for 42CrMo4, about 27% more. 20CrMoV5-7 is the more ductile: elongation 16% versus 14% for 42CrMo4, and 20CrMoV5-7 is harder (270 HB vs 245 HB). 20CrMoV5-7 runs hotter in service (500°C vs 400°C continuous) and 42CrMo4 conducts heat better (42.6 W/m·K vs 38 W/m·K).

20CrMoV5-7Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

20CrMoV5-7 vs 42CrMo4: properties

20CrMoV5-742CrMo4

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Shear Modulus

81 GPa11.7 Msi
80 GPa11.6 Msi

Tensile Strength (Ultimate)

880 MPa128 ksi
850 MPa123 ksi

Yield Strength (0.2% offset)

700 MPa102 ksi
550 MPa79.8 ksi

Elongation at Break

16%
14%

Reduction in Area

55%
40%

Compressive Strength

710 MPa103 ksi
560 MPa81.2 ksi

Shear Strength

530 MPa76.9 ksi
510 MPa74 ksi

Fatigue Strength (Endurance Limit)

420 MPa60.9 ksi
400 MPa58 ksi

Fracture Toughness (K_IC)

100 MPa·√m91 ksi·√in
75 MPa·√m68.3 ksi·√in

Charpy V-Notch Impact (RT)

55 J40.6 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 · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,425°C2,597 °F
1,420°C2,588 °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

38 W/m·K22 BTU/hr·ft·°F
42.6 W/m·K24.6 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

12 µm/m·K6.7 µin/in·°F
12.3 µm/m·K6.8 µin/in·°F

Max Service Temperature (continuous)

500°C932 °F
400°C752 °F

Same in both: 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).

Galvanic Potential (seawater, vs SCE)

-0.62 V
-0.6 V

Corrosion Resistance

15 / 100
12 / 100

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

40 / 100
35 / 100

Formability (cold)

30 / 100
35 / 100

Polishability

60 / 100
70 / 100

Brazeability / Solderability

—
50 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

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

Embodied Water

75 L/kg9 gal/lb
60 L/kg7.2 gal/lb

Same in both: Embodied Carbon (primary production) 2.2 kg CO₂/kg · Typical Recycled Content 30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

112 kN·m/kg
108 kN·m/kg

Modulus of Resilience

1,167 kJ/m³
720 kJ/m³

Thermal Diffusivity

10.4 mm²/s
11.5 mm²/s

Thermal Shock Resistance Index

13
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 scale42CrMo420CrMoV5-7

Manufacturing and finishing

Capability20CrMoV5-742CrMo4
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.

20CrMoV5-7 vs 42CrMo4 — frequently asked

Is 20CrMoV5-7 stronger than 42CrMo4?

Yes. 20CrMoV5-7 has a typical yield strength of 700 MPa (102 ksi) against 550 MPa (79.8 ksi) for 42CrMo4 — about 27% more. Tensile strength is 880 MPa (128 ksi) vs 850 MPa (123 ksi).

Which is cheaper, 20CrMoV5-7 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, 20CrMoV5-7 or 42CrMo4?

42CrMo4, by a small margin. Both rate fair for machinability — 50/100 against 45/100 for 20CrMoV5-7; for welding the order is 20CrMoV5-7 first (fair, 40/100) then 42CrMo4 (fair, 35/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 20CrMoV5-7 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.