Steel 55Cr3 vs 7CrWVMoNb9-6
Steel · grade comparison
Steel 55Cr3 and 7CrWVMoNb9-6 are both steel grades. 55Cr3 is the stronger of the two: tensile strength 800 MPa (116 ksi) against 600 MPa (87 ksi) for 7CrWVMoNb9-6, about 33% more. In exchange, 7CrWVMoNb9-6 is the more ductile: elongation 24% versus 16% for 55Cr3, and 55Cr3 is harder (225 HB vs 190 HB). 7CrWVMoNb9-6 runs hotter in service (580°C vs 400°C continuous) and 55Cr3 conducts heat better (44 W/m·K vs 30 W/m·K). On the shop floor, 7CrWVMoNb9-6 welds better (good vs poor).
55Cr3Choose it when strength drives the design.
7CrWVMoNb9-6Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
55Cr3 vs 7CrWVMoNb9-6: 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
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
Same in both: Poisson's Ratio 0.29
Physical
Density and transition temperatures.
Melting Point (Solidus)
Liquidus Temperature
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
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Min Service Temperature
Same in both: Latent Heat of Fusion 250 J/g107 BTU/lb
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
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.
Weldability
Polishability
Same in both: Machinability 50 / 100 · Machinability Rating (AISI 1212 = 100 %) 55% · Formability (cold) 45 / 100 · Brazeability / Solderability 40 / 100
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 | 55Cr3 | 7CrWVMoNb9-6 |
|---|---|---|
| CNC machining | Yes | — |
| Sheet metal | Yes | — |
| Default condition | Annealed | — |
| 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.
55Cr3 vs 7CrWVMoNb9-6 — frequently asked
Is 55Cr3 stronger than 7CrWVMoNb9-6?
Yes. 55Cr3 has a typical tensile strength of 800 MPa (116 ksi) against 600 MPa (87 ksi) for 7CrWVMoNb9-6 — about 33% more.
Which is cheaper, 55Cr3 or 7CrWVMoNb9-6?
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 welds better, 55Cr3 or 7CrWVMoNb9-6?
7CrWVMoNb9-6. Its weldability rates good (60/100) against poor (25/100) for 55Cr3.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 55Cr3 and 7CrWVMoNb9-6 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.