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Steel 1040 vs S45C

Steel · grade comparison

Steel 1040 and S45C are both steel grades, both medium carbon steel. 1040 is the stronger of the two: yield strength 415 MPa (60.2 ksi) against 380 MPa (55.1 ksi) for S45C, about 9% more. 1040 is the more ductile: elongation 25% versus 20% for S45C, and 1040 is harder (201 HB vs 187 HB).

1040Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

1040 vs S45C: properties

1040S45C

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Yield Strength (0.2% offset)

415 MPa60.2 ksi
380 MPa55.1 ksi

Elongation at Break

25%
20%

Reduction in Area

50%
45%

Compressive Strength

415 MPa60.2 ksi
380 MPa55.1 ksi

Shear Strength

385 MPa55.8 ksi
380 MPa55.1 ksi

Fatigue Strength (Endurance Limit)

290 MPa42.1 ksi
275 MPa39.9 ksi

Fracture Toughness (K_IC)

55 MPa·√m50.1 ksi·√in
50 MPa·√m45.5 ksi·√in

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

201 HB
187 HB

Hardness, Rockwell B

93 HRB
90 HRB

Hardness, Vickers

210 HV
196 HV

Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Tensile Strength (Ultimate) 620 MPa89.9 ksi

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,425°C2,597 °F
1,420°C2,588 °F

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

51 W/m·K29.5 BTU/hr·ft·°F
49 W/m·K28.3 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

11.5 µm/m·K6.4 µin/in·°F
11.7 µm/m·K6.5 µin/in·°F

Latent Heat of Fusion

247 J/g106 BTU/lb
250 J/g107 BTU/lb

Max Service Temperature (continuous)

425°C797 °F
400°C752 °F

Same in both: Specific Heat Capacity 486 J/kg·K0.12 BTU/lb·°F · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

10 % IACS
10.7 % IACS

Electrical Resistivity

1.71×10⁻⁷ Ω·m6.73 µΩ·in
1.62×10⁻⁷ Ω·m6.38 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.61 V
-0.65 V

Corrosion Resistance

10 / 100
12 / 100

Manufacturability

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

Machinability

55 / 100
58 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
57%

Formability (cold)

45 / 100
40 / 100

Brazeability / Solderability

60 / 100
65 / 100

Castability

—
45 / 100

Same in both: Weldability 45 / 100 · Polishability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

25 MJ/kg10,748 BTU/lb
26 MJ/kg11,178 BTU/lb

Typical Recycled Content

25%
30%

Same in both: Embodied Carbon (primary production) 2.1 kg CO₂/kg · Embodied Water 50 L/kg6 gal/lb

Common Calculations

Ratios derived from the values above.

Modulus of Resilience

420 kJ/m³
352 kJ/m³

Thermal Diffusivity

13.4 mm²/s
12.8 mm²/s

Same in both: Specific Strength (UTS / density) 79 kN·m/kg · Specific Stiffness (E / density) 26.1 MN·m/kg · 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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scale1040S45C

Manufacturing and finishing

Capability1040S45C
Default conditionHRNormalized
Relative cost$ Budget$ Budget
Min. machined wall0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 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 S45C — frequently asked

Is 1040 stronger than S45C?

Yes. 1040 has a typical yield strength of 415 MPa (60.2 ksi) against 380 MPa (55.1 ksi) for S45C — about 9% more. Tensile strength is 620 MPa (89.9 ksi) vs 620 MPa (89.9 ksi).

Which is cheaper, 1040 or S45C?

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 S45C?

Pick 1040 when strength drives the design, or 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 S45C 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.