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Copper Alloy C74400 vs C77000

Copper Alloy · grade comparison

Copper Alloy C74400 and C77000 are both copper alloy grades. C77000 is the stronger of the two: yield strength 505 MPa (73.2 ksi) against 440 MPa (63.8 ksi) for C74400, about 15% more; tensile strength follows at 565 MPa (81.9 ksi) vs 515 MPa (74.7 ksi). C77000 is harder — 160 HB against 138 HB for C74400 — which matters for wear surfaces and threads. C74400 runs hotter in service (200°C vs 175°C continuous) and C74400 conducts heat better (45 W/m·K vs 29 W/m·K). On the shop floor, C74400 welds better (52 vs 40 out of 100) and C74400 forms better (very good vs fair).

C74400Choose it when the part sees heat, or when it will be welded.

C77000Choose it when strength drives the design, or when surface hardness matters.

C74400 vs C77000: properties

C74400C77000

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Shear Modulus

46 GPa6.7 Msi
47 GPa6.8 Msi

Bulk Modulus

130 GPa18.9 Msi
121 GPa17.5 Msi

Poisson's Ratio

0.34
0.33

Tensile Strength (Ultimate)

515 MPa74.7 ksi
565 MPa81.9 ksi

Yield Strength (0.2% offset)

440 MPa63.8 ksi
505 MPa73.2 ksi

Shear Strength

340 MPa49.3 ksi
365 MPa52.9 ksi

Fatigue Strength (Endurance Limit)

200 MPa29 ksi
190 MPa27.6 ksi

Hardness, Brinell

138 HB
160 HB

Hardness, Rockwell B

75 HRB
84 HRB

Hardness, Vickers

145 HV
170 HV

Same in both: Elastic (Young's) Modulus 124 GPa18 Msi · Elongation at Break 12%

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,020°C1,868 °F
1,010°C1,850 °F

Liquidus Temperature

1,065°C1,949 °F
1,054°C1,929 °F

Thermal

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

Thermal Conductivity

45 W/m·K26 BTU/hr·ft·°F
29 W/m·K16.8 BTU/hr·ft·°F

Specific Heat Capacity

377 J/kg·K0.09 BTU/lb·°F
376 J/kg·K0.09 BTU/lb·°F

Latent Heat of Fusion

200 J/g86 BTU/lb
190 J/g81.7 BTU/lb

Max Service Temperature (continuous)

200°C392 °F
175°C347 °F

Same in both: Thermal Expansion (CTE, 20–100 °C) 16.2 µm/m·K9 µin/in·°F · Min Service Temperature -200°C-328 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

9.8 % IACS
5.5 % IACS

Electrical Resistivity

1.76×10⁻⁷ Ω·m6.93 µΩ·in
3.11×10⁻⁷ Ω·m12.2 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.2 V
-0.25 V

Same in both: Corrosion Resistance 62 / 100

Manufacturability

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

Machinability

25 / 100
28 / 100

Weldability

52 / 100
40 / 100

Formability (cold)

70 / 100
50 / 100

Brazeability / Solderability

85 / 100
78 / 100

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

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

62 MJ/kg26,655 BTU/lb
78 MJ/kg33,534 BTU/lb

Embodied Carbon (primary production)

4.5 kg CO₂/kg
5.6 kg CO₂/kg

Embodied Water

300 L/kg35.9 gal/lb
260 L/kg31.2 gal/lb

Same in both: Typical Recycled Content 35%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

59 kN·m/kg
65 kN·m/kg

Specific Stiffness (E / density)

14.3 MN·m/kg
14.2 MN·m/kg

Modulus of Resilience

781 kJ/m³
1,028 kJ/m³

Thermal Diffusivity

13.7 mm²/s
8.8 mm²/s

Thermal Shock Resistance Index

12
8

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 scaleC74400C77000

Manufacturing and finishing

CapabilityC74400C77000
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.

C74400 vs C77000 — frequently asked

Is C77000 stronger than C74400?

Yes. C77000 has a typical yield strength of 505 MPa (73.2 ksi) against 440 MPa (63.8 ksi) for C74400 — about 15% more. Tensile strength is 565 MPa (81.9 ksi) vs 515 MPa (74.7 ksi).

Which is cheaper, C74400 or C77000?

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 welds better, C74400 or C77000?

C74400. Its weldability rates fair (52/100) against fair (40/100) for C77000.

Ready to make it?

Upload a CAD file and FabDigit prices the part in C74400 and C77000 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.