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Copper Alloy C51000 vs C61000

Copper Alloy · grade comparison

Copper Alloy C51000 and C61000 are both copper alloy grades. C61000 is the stronger of the two: yield strength 320 MPa (46.4 ksi) against 140 MPa (20.3 ksi) for C51000, about 129% more; tensile strength follows at 585 MPa (84.8 ksi) vs 340 MPa (49.3 ksi). In exchange, C51000 is the more ductile: elongation 60% versus 25% for C61000, and C61000 is harder (160 HB vs 80 HB). C61000 is lighter (7.58 g/cm³ vs 8.86 g/cm³ for C51000) and C61000 is stiffer (117 GPa vs 110 GPa). On the shop floor, C61000 welds better (very good vs fair) and C61000 sits in a lower cost tier (high, $$$$) than C51000 (specialty, $$$$$).

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

C61000Choose it when strength drives the design, or when weight is the constraint.

C51000 vs C61000: properties

C51000C61000

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

110 GPa16 Msi
117 GPa17 Msi

Shear Modulus

41 GPa5.9 Msi
44 GPa6.4 Msi

Bulk Modulus

115 GPa16.7 Msi
118 GPa17.1 Msi

Poisson's Ratio

0.34
0.33

Tensile Strength (Ultimate)

340 MPa49.3 ksi
585 MPa84.8 ksi

Yield Strength (0.2% offset)

140 MPa20.3 ksi
320 MPa46.4 ksi

Elongation at Break

60%
25%

Shear Strength

235 MPa34.1 ksi
380 MPa55.1 ksi

Fatigue Strength (Endurance Limit)

150 MPa21.8 ksi
230 MPa33.4 ksi

Hardness, Brinell

80 HB
160 HB

Hardness, Vickers

85 HV
168 HV

Reduction in Area

—
40%

Compressive Strength

—
330 MPa47.9 ksi

Charpy V-Notch Impact (RT)

—
40 J29.5 ft·lbf

Hardness, Rockwell B

—
87 HRB

Physical

Density and transition temperatures.

Density

8.86 g/cm³0.32 lb/in³
7.58 g/cm³0.27 lb/in³

Melting Point (Solidus)

954°C1,749 °F
1,046°C1,915 °F

Liquidus Temperature

1,049°C1,920 °F
1,054°C1,929 °F

Thermal

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

Thermal Conductivity

69 W/m·K39.9 BTU/hr·ft·°F
62.8 W/m·K36.3 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
16.2 µm/m·K9 µin/in·°F

Latent Heat of Fusion

200 J/g86 BTU/lb
220 J/g94.6 BTU/lb

Max Service Temperature (continuous)

200°C392 °F
250°C482 °F

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

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 15 % IACS · Electrical Resistivity 1.15×10⁻⁷ Ω·m4.53 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.3 V
-0.28 V

Corrosion Resistance

68 / 100
78 / 100

Manufacturability

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

Machinability

25 / 100
30 / 100

Weldability

45 / 100
75 / 100

Formability (cold)

90 / 100
55 / 100

Castability

30 / 100
45 / 100

Brazeability / Solderability

90 / 100
35 / 100

Polishability

75 / 100
80 / 100

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

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

68 MJ/kg29,235 BTU/lb
57 MJ/kg24,506 BTU/lb

Embodied Carbon (primary production)

4.3 kg CO₂/kg
3.8 kg CO₂/kg

Embodied Water

260 L/kg31.2 gal/lb
320 L/kg38.3 gal/lb

Typical Recycled Content

40%
35%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

38 kN·m/kg
77 kN·m/kg

Specific Stiffness (E / density)

12.4 MN·m/kg
15.4 MN·m/kg

Modulus of Resilience

89 kJ/m³
438 kJ/m³

Thermal Diffusivity

20.5 mm²/s
22 mm²/s

Thermal Shock Resistance Index

12
19

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 scaleC51000C61000

Manufacturing and finishing

CapabilityC51000C61000
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 C61000 — frequently asked

Is C61000 stronger than C51000?

Yes. C61000 has a typical yield strength of 320 MPa (46.4 ksi) against 140 MPa (20.3 ksi) for C51000 — about 129% more. Tensile strength is 585 MPa (84.8 ksi) vs 340 MPa (49.3 ksi).

Which is cheaper, C51000 or C61000?

C61000 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 C61000?

C61000, by a small margin. Both rate poor for machinability — 30/100 against 25/100 for C51000; for welding the order is C61000 first (very good, 75/100) then C51000 (fair, 45/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C51000 and C61000 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.