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Copper Alloy C73100 vs C74400

Copper Alloy · grade comparison

Copper Alloy C73100 and C74400 are both copper alloy grades. C74400 is the stronger of the two: yield strength 440 MPa (63.8 ksi) against 345 MPa (50 ksi) for C73100, about 28% more; tensile strength follows at 515 MPa (74.7 ksi) vs 450 MPa (65.3 ksi). In exchange, C73100 is the more ductile: elongation 15% versus 12% for C74400, and C74400 is harder (145 HV vs 135 HV). On the shop floor, C73100 machines more easily (fair vs poor).

C73100Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

C74400Choose it when strength drives the design.

C73100 vs C74400: properties

C73100C74400

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

125 GPa18.1 Msi
124 GPa18 Msi

Shear Modulus

47 GPa6.8 Msi
46 GPa6.7 Msi

Bulk Modulus

125 GPa18.1 Msi
130 GPa18.9 Msi

Poisson's Ratio

0.33
0.34

Tensile Strength (Ultimate)

450 MPa65.3 ksi
515 MPa74.7 ksi

Yield Strength (0.2% offset)

345 MPa50 ksi
440 MPa63.8 ksi

Elongation at Break

15%
12%

Shear Strength

290 MPa42.1 ksi
340 MPa49.3 ksi

Fatigue Strength (Endurance Limit)

180 MPa26.1 ksi
200 MPa29 ksi

Hardness, Rockwell B

65 HRB
75 HRB

Hardness, Vickers

135 HV
145 HV

Hardness, Brinell

—
138 HB

Physical

Density and transition temperatures.

Density

8.73 g/cm³0.32 lb/in³
8.7 g/cm³0.31 lb/in³

Melting Point (Solidus)

1,040°C1,904 °F
1,020°C1,868 °F

Liquidus Temperature

1,080°C1,976 °F
1,065°C1,949 °F

Thermal

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

Latent Heat of Fusion

205 J/g88.1 BTU/lb
200 J/g86 BTU/lb

Same in both: Thermal Conductivity 45 W/m·K26 BTU/hr·ft·°F · Specific Heat Capacity 377 J/kg·K0.09 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 16.2 µm/m·K9 µin/in·°F · Max Service Temperature (continuous) 200°C392 °F · Min Service Temperature -200°C-328 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

10 % IACS
9.8 % IACS

Electrical Resistivity

1.72×10⁻⁷ Ω·m6.77 µΩ·in
1.76×10⁻⁷ Ω·m6.93 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.22 V
-0.2 V

Corrosion Resistance

60 / 100
62 / 100

Manufacturability

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

Machinability

35 / 100
25 / 100

Weldability

55 / 100
52 / 100

Formability (cold)

65 / 100
70 / 100

Castability

40 / 100
—

Same in both: Machinability Rating (AISI 1212 = 100 %) 20% · Brazeability / Solderability 85 / 100 · Polishability 90 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

65 MJ/kg27,945 BTU/lb
62 MJ/kg26,655 BTU/lb

Embodied Carbon (primary production)

4.6 kg CO₂/kg
4.5 kg CO₂/kg

Embodied Water

350 L/kg41.9 gal/lb
300 L/kg35.9 gal/lb

Same in both: Typical Recycled Content 35%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

52 kN·m/kg
59 kN·m/kg

Modulus of Resilience

476 kJ/m³
781 kJ/m³

Thermal Shock Resistance Index

10
12

Same in both: Specific Stiffness (E / density) 14.3 MN·m/kg · Thermal Diffusivity 13.7 mm²/s

Strength versus weight

Yield strength against density for every copper alloy grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

501002005001,0007.588.599.5Density (g/cm³)Yield strength (MPa) — log scaleC74400C73100

Manufacturing and finishing

CapabilityC73100C74400
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

Both take the same 4 finishes: Copper Plating, Electroless Nickel (EN), Gold Plating, Silver Plating.

C73100 vs C74400 — frequently asked

Is C74400 stronger than C73100?

Yes. C74400 has a typical yield strength of 440 MPa (63.8 ksi) against 345 MPa (50 ksi) for C73100 — about 28% more. Tensile strength is 515 MPa (74.7 ksi) vs 450 MPa (65.3 ksi).

Which is cheaper, C73100 or C74400?

Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which is easier to machine, C73100 or C74400?

C73100. Its machinability rates fair (35/100) against poor (25/100) for C74400.

Ready to make it?

Upload a CAD file and FabDigit prices the part in C73100 and C74400 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.