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Copper Alloy C74400 vs C74500

Copper Alloy · grade comparison

Copper Alloy C74400 and C74500 are both copper alloy grades. C74400 is the stronger of the two: yield strength 440 MPa (63.8 ksi) against 400 MPa (58 ksi) for C74500, about 10% more. C74500 is harder — 150 HB against 138 HB for C74400 — which matters for wear surfaces and threads. C74400 runs hotter in service (200°C vs 180°C continuous). On the shop floor, C74400 welds better (52 vs 40 out of 100) and C74400 forms better (very good vs good).

C74400Choose it when strength drives the design, or when the part sees heat.

C74500Choose it when surface hardness matters.

C74400 vs C74500: properties

C74400C74500

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

124 GPa18 Msi
127 GPa18.4 Msi

Shear Modulus

46 GPa6.7 Msi
48 GPa7 Msi

Bulk Modulus

130 GPa18.9 Msi
128 GPa18.6 Msi

Poisson's Ratio

0.34
0.33

Tensile Strength (Ultimate)

515 MPa74.7 ksi
510 MPa74 ksi

Yield Strength (0.2% offset)

440 MPa63.8 ksi
400 MPa58 ksi

Shear Strength

340 MPa49.3 ksi
330 MPa47.9 ksi

Fatigue Strength (Endurance Limit)

200 MPa29 ksi
180 MPa26.1 ksi

Hardness, Brinell

138 HB
150 HB

Hardness, Rockwell B

75 HRB
80 HRB

Hardness, Vickers

145 HV
158 HV

Same in both: Elongation at Break 12%

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,020°C1,868 °F
954°C1,749 °F

Liquidus Temperature

1,065°C1,949 °F
1,021°C1,870 °F

Thermal

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

Latent Heat of Fusion

200 J/g86 BTU/lb
195 J/g83.8 BTU/lb

Max Service Temperature (continuous)

200°C392 °F
180°C356 °F

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 · Min Service Temperature -200°C-328 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

9.8 % IACS
9 % IACS

Electrical Resistivity

1.76×10⁻⁷ Ω·m6.93 µΩ·in
1.92×10⁻⁷ Ω·m7.56 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.2 V
-0.26 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
30 / 100

Weldability

52 / 100
40 / 100

Formability (cold)

70 / 100
60 / 100

Brazeability / Solderability

85 / 100
88 / 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
5.2 kg CO₂/kg

Embodied Water

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

Typical Recycled Content

35%
40%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

59 kN·m/kg
58 kN·m/kg

Specific Stiffness (E / density)

14.3 MN·m/kg
14.5 MN·m/kg

Modulus of Resilience

781 kJ/m³
630 kJ/m³

Thermal Shock Resistance Index

12
11

Same in both: 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 scaleC74400C74500

Manufacturing and finishing

CapabilityC74400C74500
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 C74500 — frequently asked

Is C74400 stronger than C74500?

Yes. C74400 has a typical yield strength of 440 MPa (63.8 ksi) against 400 MPa (58 ksi) for C74500 — about 10% more. Tensile strength is 515 MPa (74.7 ksi) vs 510 MPa (74 ksi).

Which is cheaper, C74400 or C74500?

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, C74400 or C74500?

C74500, by a small margin. Both rate poor for machinability — 30/100 against 25/100 for C74400; for welding the order is C74400 first (fair, 52/100) then C74500 (fair, 40/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C74400 and C74500 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.