Steel 1040 vs C45
Steel · grade comparison
Steel 1040 and C45 are both steel grades, both medium carbon steel. Both yield at about 415 MPa — strength does not separate them. 1040 is the more ductile: elongation 25% versus 17% for C45, and 1040 is harder (201 HB vs 190 HB).
1040Choose it when the part is bent, formed or impact-loaded.
1040 vs C45: 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
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, Vickers
Same in both: Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29
Physical
Density and transition temperatures.
Melting Point (Solidus)
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Liquidus Temperature 1,495°C2,723 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Same in both: Specific Heat Capacity 486 J/kg·K0.12 BTU/lb·°F · Latent Heat of Fusion 247 J/g106 BTU/lb · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Electrical Resistivity
Same in both: Electrical Conductivity 10 % IACS
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability Rating (AISI 1212 = 100 %)
Formability (cold)
Brazeability / Solderability
Castability
Same in both: Machinability 55 / 100 · Weldability 45 / 100 · Polishability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Carbon (primary production)
Typical Recycled Content
Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Water 50 L/kg6 gal/lb
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Same in both: Thermal Shock Resistance Index 13
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 | 1040 | C45 |
|---|---|---|
| Default condition | HR | Normalized |
| Relative cost | $ Budget | $ Budget |
| Min. machined wall | 0.8 mm | 0.8 mm |
| Best machined surface | Ra 1.6 µm | Ra 1.6 µm |
Both are offered for CNC machining and Sheet metal. Both take the same 38 finishes: AlCrN, AlTiN, Black Oxide, CVD Al2O3, CVD TiCN, CVD TiN, Cerakote, Chrome Plating, Copper Plating, CrN, DLC, E-Coating and 26 more.
1040 vs C45 — frequently asked
What is the difference between 1040 and C45?
Steel 1040 and C45 are both steel grades, both medium carbon steel. Both yield at about 415 MPa — strength does not separate them. 1040 is the more ductile: elongation 25% versus 17% for C45, and 1040 is harder (201 HB vs 190 HB).
Which is cheaper, 1040 or C45?
Both sit in the same relative cost tier ($, budget); the part price will be decided by machining time, tolerance and quantity rather than by the material.
When should I choose 1040 over C45?
Pick 1040 when the part is bent, formed or impact-loaded.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 1040 and C45 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.