Steel M42 vs W9Mo3Cr4V
Steel · grade comparison
Steel M42 and W9Mo3Cr4V are both steel grades. M42 is the stronger of the two: yield strength 620 MPa (89.9 ksi) against 550 MPa (79.8 ksi) for W9Mo3Cr4V, about 13% more; tensile strength follows at 900 MPa (131 ksi) vs 850 MPa (123 ksi). In exchange, W9Mo3Cr4V is the more ductile: elongation 18% versus 12% for M42, and M42 is harder (255 HB vs 240 HB). M42 is lighter (7.98 g/cm³ vs 8.3 g/cm³ for W9Mo3Cr4V). On the shop floor, W9Mo3Cr4V sits in a lower cost tier (high, $$$$) than M42 (specialty, $$$$$).
M42Choose it when strength drives the design, or when weight is the constraint.
W9Mo3Cr4VChoose it when the part is bent, formed or impact-loaded, or when cost is the deciding factor.
M42 vs W9Mo3Cr4V: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Shear Modulus
Bulk Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Rockwell C
Hardness, Vickers
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Min Service Temperature
Latent Heat of Fusion
Same in both: Specific Heat Capacity 420 J/kg·K0.1 BTU/lb·°F · Max Service Temperature (continuous) 400°C752 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Same in both: Electrical Resistivity 5.5×10⁻⁷ Ω·m21.7 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Galvanic Potential (seawater, vs SCE)
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Castability
Brazeability / Solderability
Polishability
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
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.
Manufacturing and finishing
| Capability | M42 | W9Mo3Cr4V |
|---|---|---|
| CNC machining | Yes | — |
| Default condition | Annealed | — |
| Relative cost | $$$$$ Specialty | $$$$ High |
| Min. machined wall | 0.8 mm | — |
| Best machined surface | Ra 1.6 µm | — |
| AlCrN | Yes | — |
| AlTiN | Yes | — |
| Black Oxide | Yes | — |
| CVD Al2O3 | Yes | — |
| CVD TiCN | Yes | — |
| CVD TiN | Yes | — |
| Cerakote | Yes | — |
| Chrome Plating | Yes | — |
| CrN | Yes | — |
| DLC | Yes | — |
| E-Coating | Yes | — |
| HVOF Coating | Yes | — |
| Hot-Dip Galvanizing | Yes | — |
| MoS2 | Yes | — |
| Multilayer CVD | Yes | — |
| Nickel Plating | Yes | — |
| PTFE Coating | Yes | — |
| Painting | Yes | — |
They share 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.
M42 vs W9Mo3Cr4V — frequently asked
Is M42 stronger than W9Mo3Cr4V?
Yes. M42 has a typical yield strength of 620 MPa (89.9 ksi) against 550 MPa (79.8 ksi) for W9Mo3Cr4V — about 13% more. Tensile strength is 900 MPa (131 ksi) vs 850 MPa (123 ksi).
Which is cheaper, M42 or W9Mo3Cr4V?
W9Mo3Cr4V is the lower-cost material: it sits in the high tier ($$$$) while M42 is specialty ($$$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
Which welds better, M42 or W9Mo3Cr4V?
W9Mo3Cr4V. Its weldability rates poor (25/100) against poor (20/100) for M42.
Ready to make it?
Upload a CAD file and FabDigit prices the part in M42 and W9Mo3Cr4V 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.