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Steel M42 vs W6Mo5Cr4V3

Steel · grade comparison

Steel M42 and W6Mo5Cr4V3 are both steel grades. M42 is the stronger of the two: yield strength 620 MPa (89.9 ksi) against 560 MPa (81.2 ksi) for W6Mo5Cr4V3, about 11% more. M42 runs hotter in service (400°C vs 300°C continuous). On the shop floor, W6Mo5Cr4V3 sits in a lower cost tier (premium, $$$) than M42 (specialty, $$$$$).

M42Choose it when strength drives the design, or when the part sees heat.

W6Mo5Cr4V3Choose it when cost is the deciding factor.

M42 vs W6Mo5Cr4V3: properties

M42W6Mo5Cr4V3

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

222 GPa32.2 Msi
217 GPa31.5 Msi

Shear Modulus

86 GPa12.5 Msi
84 GPa12.2 Msi

Poisson's Ratio

0.28
0.29

Tensile Strength (Ultimate)

900 MPa131 ksi
860 MPa125 ksi

Yield Strength (0.2% offset)

620 MPa89.9 ksi
560 MPa81.2 ksi

Reduction in Area

20%
25%

Compressive Strength

680 MPa98.6 ksi
1,600 MPa232 ksi

Shear Strength

545 MPa79 ksi
550 MPa79.8 ksi

Fracture Toughness (K_IC)

33 MPa·√m30 ksi·√in
22 MPa·√m20 ksi·√in

Charpy V-Notch Impact (RT)

9 J6.6 ft·lbf
12 J8.9 ft·lbf

Hardness, Brinell

255 HB
248 HB

Hardness, Rockwell B

101 HRB
100 HRB

Hardness, Rockwell C

25 HRC
—

Hardness, Vickers

270 HV
260 HV

Same in both: Bulk Modulus 165 GPa23.9 Msi · Elongation at Break 12% · Fatigue Strength (Endurance Limit) 400 MPa58 ksi

Physical

Density and transition temperatures.

Density

7.98 g/cm³0.29 lb/in³
8.05 g/cm³0.29 lb/in³

Melting Point (Solidus)

1,290°C2,354 °F
1,250°C2,282 °F

Same in both: Liquidus Temperature 1,420°C2,588 °F

Thermal

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

Thermal Conductivity

22 W/m·K12.7 BTU/hr·ft·°F
24 W/m·K13.9 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

10.8 µm/m·K6 µin/in·°F
10.5 µm/m·K5.8 µin/in·°F

Max Service Temperature (continuous)

400°C752 °F
300°C572 °F

Latent Heat of Fusion

—
250 J/g107 BTU/lb

Same in both: Specific Heat Capacity 420 J/kg·K0.1 BTU/lb·°F · Min Service Temperature -60°C-76 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

3.1 % IACS
3.2 % IACS

Electrical Resistivity

5.5×10⁻⁷ Ω·m21.7 µΩ·in
5.4×10⁻⁷ Ω·m21.3 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

18 / 100
16 / 100

Manufacturability

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

Machinability

38 / 100
30 / 100

Machinability Rating (AISI 1212 = 100 %)

42%
38%

Weldability

20 / 100
12 / 100

Formability (cold)

10 / 100
8 / 100

Castability

20 / 100
25 / 100

Polishability

80 / 100
72 / 100

Same in both: Brazeability / Solderability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

4.4 kg CO₂/kg
4.2 kg CO₂/kg

Typical Recycled Content

30%
40%

Same in both: Embodied Energy (primary production) 62 MJ/kg26,655 BTU/lb · Embodied Water 90 L/kg10.8 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

113 kN·m/kg
107 kN·m/kg

Specific Stiffness (E / density)

27.8 MN·m/kg
27 MN·m/kg

Modulus of Resilience

866 kJ/m³
723 kJ/m³

Thermal Diffusivity

6.6 mm²/s
7.1 mm²/s

Thermal Shock Resistance Index

8
9

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 scaleM42W6Mo5Cr4V3

Manufacturing and finishing

CapabilityM42W6Mo5Cr4V3
CNC machiningYes—
Default conditionAnnealed—
Relative cost$$$$$ Specialty$$$ Premium
Min. machined wall0.8 mm—
Best machined surfaceRa 1.6 µm—
AlCrNYes—
AlTiNYes—
Black OxideYes—
CVD Al2O3Yes—
CVD TiCNYes—
CVD TiNYes—
CerakoteYes—
Chrome PlatingYes—
CrNYes—
DLCYes—
E-CoatingYes—
HVOF CoatingYes—
Hot-Dip GalvanizingYes—
MoS2Yes—
Multilayer CVDYes—
Nickel PlatingYes—
PTFE CoatingYes—
PaintingYes—

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

M42 vs W6Mo5Cr4V3 — frequently asked

Is M42 stronger than W6Mo5Cr4V3?

Yes. M42 has a typical yield strength of 620 MPa (89.9 ksi) against 560 MPa (81.2 ksi) for W6Mo5Cr4V3 — about 11% more. Tensile strength is 900 MPa (131 ksi) vs 860 MPa (125 ksi).

Which is cheaper, M42 or W6Mo5Cr4V3?

W6Mo5Cr4V3 is the lower-cost material: it sits in the premium tier ($$$) while M42 is specialty ($$$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, M42 or W6Mo5Cr4V3?

M42. Its machinability rates fair (38/100) against poor (30/100) for W6Mo5Cr4V3; for welding the order is M42 first (poor, 20/100) then W6Mo5Cr4V3 (not recommended, 12/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in M42 and W6Mo5Cr4V3 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.