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Copper Alloy C26000 vs C66300

Copper Alloy · grade comparison

Copper Alloy C26000 and C66300 are both copper alloy grades. C66300 is the stronger of the two: yield strength 600 MPa (87 ksi) against 105 MPa (15.2 ksi) for C26000, about 5.7 times as much; tensile strength follows at 660 MPa (95.7 ksi) vs 325 MPa (47.1 ksi). In exchange, C26000 is the more ductile: elongation 62% versus 3.5% for C66300, and C66300 is harder (195 HV vs 60 HV). C26000 runs hotter in service (200°C vs 120°C continuous) and C26000 conducts heat better (121 W/m·K vs 105 W/m·K). On the shop floor, C26000 welds better (fair vs poor).

C26000Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

C66300Choose it when strength drives the design.

C26000 vs C66300: properties

C26000C66300

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Poisson's Ratio

0.35
0.34

Tensile Strength (Ultimate)

325 MPa47.1 ksi
660 MPa95.7 ksi

Yield Strength (0.2% offset)

105 MPa15.2 ksi
600 MPa87 ksi

Elongation at Break

62%
3.5%

Shear Strength

234 MPa33.9 ksi
380 MPa55.1 ksi

Fatigue Strength (Endurance Limit)

97 MPa14.1 ksi
180 MPa26.1 ksi

Hardness, Brinell

55 HB
—

Hardness, Vickers

60 HV
195 HV

Hardness, Rockwell B

—
85 HRB

Same in both: Elastic (Young's) Modulus 110 GPa16 Msi · Shear Modulus 41 GPa5.9 Msi · Bulk Modulus 115 GPa16.7 Msi

Physical

Density and transition temperatures.

Density

8.53 g/cm³0.31 lb/in³
8.55 g/cm³0.31 lb/in³

Melting Point (Solidus)

915°C1,679 °F
900°C1,652 °F

Liquidus Temperature

955°C1,751 °F
935°C1,715 °F

Thermal

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

Thermal Conductivity

121 W/m·K69.9 BTU/hr·ft·°F
105 W/m·K60.7 BTU/hr·ft·°F

Latent Heat of Fusion

165 J/g70.9 BTU/lb
170 J/g73.1 BTU/lb

Max Service Temperature (continuous)

200°C392 °F
120°C248 °F

Same in both: Specific Heat Capacity 375 J/kg·K0.09 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 19.9 µm/m·K11.1 µin/in·°F · Min Service Temperature -200°C-328 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

28 % IACS
25 % IACS

Electrical Resistivity

6.2×10⁻⁸ Ω·m2.44 µΩ·in
6.9×10⁻⁸ Ω·m2.72 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.28 V
-0.25 V

Corrosion Resistance

50 / 100
58 / 100

Manufacturability

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

Machinability

30 / 100
35 / 100

Weldability

40 / 100
30 / 100

Formability (cold)

98 / 100
20 / 100

Castability

25 / 100
—

Brazeability / Solderability

90 / 100
80 / 100

Polishability

85 / 100
80 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 30%

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

55 MJ/kg23,646 BTU/lb
58 MJ/kg24,936 BTU/lb

Embodied Carbon (primary production)

3.5 kg CO₂/kg
3.6 kg CO₂/kg

Embodied Water

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

Typical Recycled Content

45%
50%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

38 kN·m/kg
77 kN·m/kg

Modulus of Resilience

50 kJ/m³
1,636 kJ/m³

Thermal Diffusivity

37.8 mm²/s
32.7 mm²/s

Thermal Shock Resistance Index

18
32

Same in both: Specific Stiffness (E / density) 12.9 MN·m/kg

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 scaleC26000C66300

Manufacturing and finishing

CapabilityC26000C66300
CNC machiningYes—
Sheet metalYes—
Default conditionO—
Relative cost$$$$ High$$$$ 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.

C26000 vs C66300 — frequently asked

Is C66300 stronger than C26000?

Yes. C66300 has a typical yield strength of 600 MPa (87 ksi) against 105 MPa (15.2 ksi) for C26000 — about 5.7 times as much. Tensile strength is 660 MPa (95.7 ksi) vs 325 MPa (47.1 ksi).

Which is cheaper, C26000 or C66300?

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, C26000 or C66300?

C66300. Its machinability rates fair (35/100) against poor (30/100) for C26000; for welding the order is C26000 first (fair, 40/100) then C66300 (poor, 30/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C26000 and C66300 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.