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Copper Alloy C21000 vs C26000

Copper Alloy · grade comparison

Copper Alloy C21000 and C26000 are both copper alloy grades. C26000 is the stronger of the two: yield strength 105 MPa (15.2 ksi) against 75 MPa (10.9 ksi) for C21000, about 40% more; tensile strength follows at 325 MPa (47.1 ksi) vs 240 MPa (34.8 ksi). C26000 is the more ductile: elongation 62% versus 45% for C21000, and C26000 is harder (55 HB vs 45 HB). C26000 is lighter (8.53 g/cm³ vs 8.86 g/cm³ for C21000) and C21000 conducts heat better (226 W/m·K vs 121 W/m·K). On the shop floor, C21000 welds better (good vs fair).

C21000Choose it when it will be welded.

C26000Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

C21000 vs C26000: properties

C21000C26000

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

115 GPa16.7 Msi
110 GPa16 Msi

Shear Modulus

43 GPa6.2 Msi
41 GPa5.9 Msi

Bulk Modulus

128 GPa18.6 Msi
115 GPa16.7 Msi

Poisson's Ratio

0.34
0.35

Tensile Strength (Ultimate)

240 MPa34.8 ksi
325 MPa47.1 ksi

Yield Strength (0.2% offset)

75 MPa10.9 ksi
105 MPa15.2 ksi

Elongation at Break

45%
62%

Reduction in Area

70%
—

Shear Strength

165 MPa23.9 ksi
234 MPa33.9 ksi

Fatigue Strength (Endurance Limit)

90 MPa13.1 ksi
97 MPa14.1 ksi

Hardness, Brinell

45 HB
55 HB

Hardness, Vickers

50 HV
60 HV

Physical

Density and transition temperatures.

Density

8.86 g/cm³0.32 lb/in³
8.53 g/cm³0.31 lb/in³

Melting Point (Solidus)

1,055°C1,931 °F
915°C1,679 °F

Liquidus Temperature

1,066°C1,951 °F
955°C1,751 °F

Thermal

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

Thermal Conductivity

226 W/m·K131 BTU/hr·ft·°F
121 W/m·K69.9 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

18.1 µm/m·K10.1 µin/in·°F
19.9 µm/m·K11.1 µin/in·°F

Latent Heat of Fusion

205 J/g88.1 BTU/lb
165 J/g70.9 BTU/lb

Same in both: Max Service Temperature (continuous) 200°C392 °F · Min Service Temperature -200°C-328 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

56 % IACS
28 % IACS

Electrical Resistivity

3.08×10⁻⁸ Ω·m1.21 µΩ·in
6.2×10⁻⁸ Ω·m2.44 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.22 V
-0.28 V

Corrosion Resistance

62 / 100
50 / 100

Manufacturability

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

Machinability

22 / 100
30 / 100

Machinability Rating (AISI 1212 = 100 %)

20%
30%

Weldability

60 / 100
40 / 100

Formability (cold)

97 / 100
98 / 100

Castability

45 / 100
25 / 100

Brazeability / Solderability

95 / 100
90 / 100

Polishability

90 / 100
85 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

3.8 kg CO₂/kg
3.5 kg CO₂/kg

Embodied Water

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

Same in both: Embodied Energy (primary production) 55 MJ/kg23,646 BTU/lb · Typical Recycled Content 45%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

27 kN·m/kg
38 kN·m/kg

Specific Stiffness (E / density)

13 MN·m/kg
12.9 MN·m/kg

Modulus of Resilience

24 kJ/m³
50 kJ/m³

Thermal Diffusivity

67.1 mm²/s
37.8 mm²/s

Thermal Shock Resistance Index

26
18

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 scaleC26000C21000

Manufacturing and finishing

CapabilityC21000C26000
CNC machining—Yes
Sheet metal—Yes
Default condition—O
Relative cost$$$$ High$$$$ High
Min. machined wall—0.8 mm
Best machined surface—Ra 1.6 µm
Chrome Plating—Yes
Electropolishing—Yes
Nickel Plating—Yes
Painting—Yes
Tin Plating—Yes

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

C21000 vs C26000 — frequently asked

Is C26000 stronger than C21000?

Yes. C26000 has a typical yield strength of 105 MPa (15.2 ksi) against 75 MPa (10.9 ksi) for C21000 — about 40% more. Tensile strength is 325 MPa (47.1 ksi) vs 240 MPa (34.8 ksi).

Which is cheaper, C21000 or C26000?

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, C21000 or C26000?

C26000, by a small margin. Both rate poor for machinability — 30/100 against 22/100 for C21000; for welding the order is C21000 first (good, 60/100) then C26000 (fair, 40/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C21000 and C26000 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.