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Copper Alloy C71000 vs C74400

Copper Alloy · grade comparison

Copper Alloy C71000 and C74400 are both copper alloy grades. C74400 is the stronger of the two: yield strength 440 MPa (63.8 ksi) against 110 MPa (16 ksi) for C71000, about 4.0 times as much; tensile strength follows at 515 MPa (74.7 ksi) vs 340 MPa (49.3 ksi). In exchange, C71000 is the more ductile: elongation 40% versus 12% for C74400, and C74400 is harder (138 HB vs 75 HB). C71000 is stiffer (138 GPa vs 124 GPa) and C71000 runs hotter in service (320°C vs 200°C continuous). On the shop floor, C71000 welds better (excellent vs fair).

C71000Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

C74400Choose it when strength drives the design.

C71000 vs C74400: properties

C71000C74400

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

138 GPa20 Msi
124 GPa18 Msi

Shear Modulus

52 GPa7.5 Msi
46 GPa6.7 Msi

Bulk Modulus

132 GPa19.1 Msi
130 GPa18.9 Msi

Poisson's Ratio

0.32
0.34

Tensile Strength (Ultimate)

340 MPa49.3 ksi
515 MPa74.7 ksi

Yield Strength (0.2% offset)

110 MPa16 ksi
440 MPa63.8 ksi

Elongation at Break

40%
12%

Reduction in Area

65%
—

Shear Strength

240 MPa34.8 ksi
340 MPa49.3 ksi

Fatigue Strength (Endurance Limit)

140 MPa20.3 ksi
200 MPa29 ksi

Hardness, Brinell

75 HB
138 HB

Hardness, Rockwell B

40 HRB
75 HRB

Hardness, Vickers

80 HV
145 HV

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,099°C2,010 °F
1,020°C1,868 °F

Liquidus Temperature

1,149°C2,100 °F
1,065°C1,949 °F

Thermal

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

Thermal Conductivity

37 W/m·K21.4 BTU/hr·ft·°F
45 W/m·K26 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

15.6 µm/m·K8.7 µin/in·°F
16.2 µm/m·K9 µin/in·°F

Latent Heat of Fusion

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

Max Service Temperature (continuous)

320°C608 °F
200°C392 °F

Same in both: Min Service Temperature -200°C-328 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

6.5 % IACS
9.8 % IACS

Electrical Resistivity

2.65×10⁻⁷ Ω·m10.4 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)

-0.27 V
-0.2 V

Corrosion Resistance

75 / 100
62 / 100

Manufacturability

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

Machinability

20 / 100
25 / 100

Weldability

85 / 100
52 / 100

Formability (cold)

90 / 100
70 / 100

Castability

45 / 100
—

Brazeability / Solderability

88 / 100
85 / 100

Polishability

85 / 100
90 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 20%

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

72 MJ/kg30,954 BTU/lb
62 MJ/kg26,655 BTU/lb

Embodied Carbon (primary production)

5.2 kg CO₂/kg
4.5 kg CO₂/kg

Embodied Water

320 L/kg38.3 gal/lb
300 L/kg35.9 gal/lb

Typical Recycled Content

30%
35%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

38 kN·m/kg
59 kN·m/kg

Specific Stiffness (E / density)

15.4 MN·m/kg
14.3 MN·m/kg

Modulus of Resilience

44 kJ/m³
781 kJ/m³

Thermal Diffusivity

10.9 mm²/s
13.7 mm²/s

Thermal Shock Resistance Index

6
12

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 scaleC74400C71000

Manufacturing and finishing

CapabilityC71000C74400
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.

C71000 vs C74400 — frequently asked

Is C74400 stronger than C71000?

Yes. C74400 has a typical yield strength of 440 MPa (63.8 ksi) against 110 MPa (16 ksi) for C71000 — about 4.0 times as much. Tensile strength is 515 MPa (74.7 ksi) vs 340 MPa (49.3 ksi).

Which is cheaper, C71000 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, C71000 or C74400?

C74400, by a small margin. Both rate poor for machinability — 25/100 against 20/100 for C71000; for welding the order is C71000 first (excellent, 85/100) then C74400 (fair, 52/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C71000 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.