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Copper Alloy C51000 vs C67000

Copper Alloy · grade comparison

Copper Alloy C51000 and C67000 are both copper alloy grades. C67000 is the stronger of the two: yield strength 379 MPa (55 ksi) against 140 MPa (20.3 ksi) for C51000, about 171% more; tensile strength follows at 655 MPa (95 ksi) vs 340 MPa (49.3 ksi). In exchange, C51000 is the more ductile: elongation 60% versus 20% for C67000, and C67000 is harder (185 HB vs 80 HB). C67000 is lighter (8.36 g/cm³ vs 8.86 g/cm³ for C51000) and C51000 is stiffer (110 GPa vs 103 GPa). On the shop floor, C51000 welds better (fair vs poor) and C67000 sits in a lower cost tier (high, $$$$) than C51000 (specialty, $$$$$).

C51000Choose it when the part is bent, formed or impact-loaded, or when it will be welded.

C67000Choose it when strength drives the design, or when weight is the constraint.

C51000 vs C67000: properties

C51000C67000

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

110 GPa16 Msi
103 GPa14.9 Msi

Shear Modulus

41 GPa5.9 Msi
39 GPa5.7 Msi

Bulk Modulus

115 GPa16.7 Msi
110 GPa16 Msi

Tensile Strength (Ultimate)

340 MPa49.3 ksi
655 MPa95 ksi

Yield Strength (0.2% offset)

140 MPa20.3 ksi
379 MPa55 ksi

Elongation at Break

60%
20%

Shear Strength

235 MPa34.1 ksi
415 MPa60.2 ksi

Fatigue Strength (Endurance Limit)

150 MPa21.8 ksi
240 MPa34.8 ksi

Hardness, Brinell

80 HB
185 HB

Hardness, Vickers

85 HV
—

Reduction in Area

—
35%

Charpy V-Notch Impact (RT)

—
25 J18.4 ft·lbf

Hardness, Rockwell B

—
89 HRB

Same in both: Poisson's Ratio 0.34

Physical

Density and transition temperatures.

Density

8.86 g/cm³0.32 lb/in³
8.36 g/cm³0.3 lb/in³

Melting Point (Solidus)

954°C1,749 °F
862°C1,584 °F

Liquidus Temperature

1,049°C1,920 °F
880°C1,616 °F

Thermal

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

Thermal Conductivity

69 W/m·K39.9 BTU/hr·ft·°F
42 W/m·K24.3 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)

17.8 µm/m·K9.9 µin/in·°F
21.6 µm/m·K12 µin/in·°F

Min Service Temperature

-200°C-328 °F
-100°C-148 °F

Same in both: Latent Heat of Fusion 200 J/g86 BTU/lb · Max Service Temperature (continuous) 200°C392 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

15 % IACS
12 % IACS

Electrical Resistivity

1.15×10⁻⁷ Ω·m4.53 µΩ·in
1.44×10⁻⁷ Ω·m5.67 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

68 / 100
55 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.3 V

Manufacturability

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

Machinability

25 / 100
32 / 100

Machinability Rating (AISI 1212 = 100 %)

20%
55%

Weldability

45 / 100
30 / 100

Formability (cold)

90 / 100
40 / 100

Castability

30 / 100
60 / 100

Brazeability / Solderability

90 / 100
30 / 100

Polishability

75 / 100
70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

68 MJ/kg29,235 BTU/lb
42 MJ/kg18,057 BTU/lb

Embodied Carbon (primary production)

4.3 kg CO₂/kg
2.8 kg CO₂/kg

Embodied Water

260 L/kg31.2 gal/lb
250 L/kg30 gal/lb

Same in both: Typical Recycled Content 40%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

38 kN·m/kg
78 kN·m/kg

Specific Stiffness (E / density)

12.4 MN·m/kg
12.3 MN·m/kg

Modulus of Resilience

89 kJ/m³
697 kJ/m³

Thermal Diffusivity

20.5 mm²/s
13.3 mm²/s

Same in both: Thermal Shock Resistance Index 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 scaleC51000C67000

Manufacturing and finishing

CapabilityC51000C67000
CNC machiningYes—
Sheet metalYes—
Default conditionO—
Relative cost$$$$$ Specialty$$$$ High
Min. machined wall0.8 mm—
Best machined surfaceRa 1.6 µm—
Chrome PlatingYes—
ElectropolishingYes—
Nickel PlatingYes—
PaintingYes—
Tin PlatingYes—

They share 4 finishes: Copper Plating, Electroless Nickel (EN), Gold Plating, Silver Plating.

C51000 vs C67000 — frequently asked

Is C67000 stronger than C51000?

Yes. C67000 has a typical yield strength of 379 MPa (55 ksi) against 140 MPa (20.3 ksi) for C51000 — about 171% more. Tensile strength is 655 MPa (95 ksi) vs 340 MPa (49.3 ksi).

Which is cheaper, C51000 or C67000?

C67000 is the lower-cost material: it sits in the high tier ($$$$) while C51000 is specialty ($$$$$). 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, C51000 or C67000?

C67000, by a small margin. Both rate poor for machinability — 32/100 against 25/100 for C51000; for welding the order is C51000 first (fair, 45/100) then C67000 (poor, 30/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C51000 and C67000 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.