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Steel 35# vs C5

Steel · grade comparison

Steel 35# and C5 are both steel grades. C5 is the stronger of the two: yield strength 470 MPa (68.2 ksi) against 330 MPa (47.9 ksi) for 35#, about 42% more; tensile strength follows at 690 MPa (100 ksi) vs 560 MPa (81.2 ksi). C5 is harder — 205 HB against 160 HB for 35# — which matters for wear surfaces and threads. C5 runs hotter in service (620°C vs 400°C continuous) and 35# conducts heat better (49 W/m·K vs 36 W/m·K). On the shop floor, 35# machines more easily (good vs fair), 35# welds better (good vs fair), and 35# forms better (fair vs not recommended).

35#Choose it when the part is machined in volume, or when it will be welded.

C5Choose it when strength drives the design, or when surface hardness matters.

35# vs C5: properties

35#C5

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

560 MPa81.2 ksi
690 MPa100 ksi

Yield Strength (0.2% offset)

330 MPa47.9 ksi
470 MPa68.2 ksi

Reduction in Area

50%
45%

Shear Strength

400 MPa58 ksi
420 MPa60.9 ksi

Fatigue Strength (Endurance Limit)

250 MPa36.3 ksi
310 MPa45 ksi

Fracture Toughness (K_IC)

55 MPa·√m50.1 ksi·√in
80 MPa·√m72.8 ksi·√in

Charpy V-Notch Impact (RT)

60 J44.3 ft·lbf
35 J25.8 ft·lbf

Hardness, Brinell

160 HB
205 HB

Hardness, Rockwell B

83 HRB
—

Hardness, Vickers

168 HV
215 HV

Compressive Strength

—
470 MPa68.2 ksi

Hardness, Rockwell C

—
16 HRC

Same in both: Elastic (Young's) Modulus 207 GPa30 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Elongation at Break 22%

Physical

Density and transition temperatures.

Density

7.85 g/cm³0.28 lb/in³
7.75 g/cm³0.28 lb/in³

Melting Point (Solidus)

1,425°C2,597 °F
1,420°C2,588 °F

Same in both: Liquidus Temperature 1,500°C2,732 °F

Thermal

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

Thermal Conductivity

49 W/m·K28.3 BTU/hr·ft·°F
36 W/m·K20.8 BTU/hr·ft·°F

Specific Heat Capacity

477 J/kg·K0.11 BTU/lb·°F
470 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

11.6 µm/m·K6.4 µin/in·°F
11.8 µm/m·K6.6 µin/in·°F

Latent Heat of Fusion

250 J/g107 BTU/lb
270 J/g116 BTU/lb

Max Service Temperature (continuous)

400°C752 °F
620°C1,148 °F

Min Service Temperature

-20°C-4 °F
-29°C-20 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

10 % IACS
—

Electrical Resistivity

1.7×10⁻⁷ Ω·m6.69 µΩ·in
5.5×10⁻⁷ Ω·m21.7 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.65 V
-0.55 V

Corrosion Resistance

11 / 100
28 / 100

Manufacturability

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

Machinability

60 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
45%

Weldability

55 / 100
35 / 100

Formability (cold)

45 / 100
10 / 100

Castability

35 / 100
55 / 100

Brazeability / Solderability

65 / 100
35 / 100

Polishability

55 / 100
50 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

25 MJ/kg10,748 BTU/lb
30 MJ/kg12,898 BTU/lb

Embodied Carbon (primary production)

1.9 kg CO₂/kg
2.3 kg CO₂/kg

Embodied Water

40 L/kg4.8 gal/lb
60 L/kg7.2 gal/lb

Typical Recycled Content

25%
75%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

71 kN·m/kg
89 kN·m/kg

Specific Stiffness (E / density)

26.4 MN·m/kg
26.7 MN·m/kg

Modulus of Resilience

263 kJ/m³
534 kJ/m³

Thermal Diffusivity

13.1 mm²/s
9.9 mm²/s

Thermal Shock Resistance Index

11
10

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 scale35#C5

Manufacturing and finishing

Capability35#C5
CNC machiningYes—
Sheet metalYes—
Default conditionHR—
Relative cost$ Budget$$$ 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.

35# vs C5 — frequently asked

Is C5 stronger than 35#?

Yes. C5 has a typical yield strength of 470 MPa (68.2 ksi) against 330 MPa (47.9 ksi) for 35# — about 42% more. Tensile strength is 690 MPa (100 ksi) vs 560 MPa (81.2 ksi).

Which is cheaper, 35# or C5?

35# is the lower-cost material: it sits in the budget tier ($) while C5 is premium ($$$). 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, 35# or C5?

35#. Its machinability rates good (60/100) against fair (45/100) for C5; for welding the order is 35# first (good, 55/100) then C5 (fair, 35/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 35# and C5 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.