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Copper Alloy C33000 vs C68800

Copper Alloy · grade comparison

Copper Alloy C33000 and C68800 are both copper alloy grades. C68800 is the stronger of the two: yield strength 620 MPa (89.9 ksi) against 110 MPa (16 ksi) for C33000, about 5.6 times as much; tensile strength follows at 725 MPa (105 ksi) vs 340 MPa (49.3 ksi). In exchange, C33000 is the more ductile: elongation 55% versus 5% for C68800, and C68800 is harder (200 HV vs 58 HV). C68800 is lighter (8.17 g/cm³ vs 8.47 g/cm³ for C33000) and C68800 is stiffer (117 GPa vs 103 GPa). On the shop floor, C33000 machines more easily (very good vs poor).

C33000Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

C68800Choose it when strength drives the design, or when weight is the constraint.

C33000 vs C68800: properties

C33000C68800

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

103 GPa14.9 Msi
117 GPa17 Msi

Shear Modulus

39 GPa5.7 Msi
44 GPa6.4 Msi

Bulk Modulus

111 GPa16.1 Msi
108 GPa15.7 Msi

Poisson's Ratio

0.34
0.32

Tensile Strength (Ultimate)

340 MPa49.3 ksi
725 MPa105 ksi

Yield Strength (0.2% offset)

110 MPa16 ksi
620 MPa89.9 ksi

Elongation at Break

55%
5%

Reduction in Area

62%
—

Shear Strength

220 MPa31.9 ksi
435 MPa63.1 ksi

Fatigue Strength (Endurance Limit)

105 MPa15.2 ksi
240 MPa34.8 ksi

Charpy V-Notch Impact (RT)

55 J40.6 ft·lbf
—

Hardness, Brinell

55 HB
—

Hardness, Vickers

58 HV
200 HV

Hardness, Rockwell B

—
90 HRB

Physical

Density and transition temperatures.

Density

8.47 g/cm³0.31 lb/in³
8.17 g/cm³0.3 lb/in³

Melting Point (Solidus)

899°C1,650 °F
932°C1,710 °F

Liquidus Temperature

954°C1,749 °F
949°C1,740 °F

Thermal

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

Thermal Conductivity

121 W/m·K69.9 BTU/hr·ft·°F
71 W/m·K41 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

20.2 µm/m·K11.2 µin/in·°F
18.4 µm/m·K10.2 µin/in·°F

Latent Heat of Fusion

170 J/g73.1 BTU/lb
200 J/g86 BTU/lb

Max Service Temperature (continuous)

200°C392 °F
150°C302 °F

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

Electrical

Conductivity and insulation.

Electrical Conductivity

26 % IACS
18 % IACS

Electrical Resistivity

6.6×10⁻⁸ Ω·m2.6 µΩ·in
9.6×10⁻⁸ Ω·m3.78 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.25 V
-0.26 V

Corrosion Resistance

55 / 100
68 / 100

Manufacturability

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

Machinability

70 / 100
33 / 100

Machinability Rating (AISI 1212 = 100 %)

180%
40%

Formability (cold)

85 / 100
45 / 100

Brazeability / Solderability

85 / 100
70 / 100

Polishability

80 / 100
75 / 100

Castability

—
30 / 100

Same in both: Weldability 25 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

55 MJ/kg23,646 BTU/lb
46 MJ/kg19,776 BTU/lb

Embodied Carbon (primary production)

3.6 kg CO₂/kg
3.1 kg CO₂/kg

Embodied Water

180 L/kg21.6 gal/lb
250 L/kg30 gal/lb

Typical Recycled Content

50%
35%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

40 kN·m/kg
89 kN·m/kg

Specific Stiffness (E / density)

12.2 MN·m/kg
14.3 MN·m/kg

Modulus of Resilience

59 kJ/m³
1,643 kJ/m³

Thermal Diffusivity

38.1 mm²/s
23.1 mm²/s

Thermal Shock Resistance Index

20
24

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 scaleC33000C68800

Manufacturing and finishing

CapabilityC33000C68800
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.

C33000 vs C68800 — frequently asked

Is C68800 stronger than C33000?

Yes. C68800 has a typical yield strength of 620 MPa (89.9 ksi) against 110 MPa (16 ksi) for C33000 — about 5.6 times as much. Tensile strength is 725 MPa (105 ksi) vs 340 MPa (49.3 ksi).

Which is cheaper, C33000 or C68800?

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, C33000 or C68800?

C33000. Its machinability rates very good (70/100) against poor (33/100) for C68800.

Ready to make it?

Upload a CAD file and FabDigit prices the part in C33000 and C68800 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.