Copper Alloy C28000 vs C66900
Copper Alloy · grade comparison
Copper Alloy C28000 and C66900 are both copper alloy grades. C66900 is the stronger of the two: yield strength 565 MPa (81.9 ksi) against 145 MPa (21 ksi) for C28000, about 3.9 times as much; tensile strength follows at 700 MPa (102 ksi) vs 372 MPa (54 ksi). In exchange, C28000 is the more ductile: elongation 45% versus 7% for C66900, and C66900 is harder (185 HB vs 75 HB). C66900 is lighter (8.1 g/cm³ vs 8.39 g/cm³ for C28000) and C28000 runs hotter in service (200°C vs 150°C continuous). On the shop floor, C28000 machines more easily (good vs poor), C28000 welds better (50 vs 40 out of 100), and C28000 sits in a lower cost tier (premium, $$$) than C66900 (high, $$$$).
C28000Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
C66900Choose it when strength drives the design, or when weight is the constraint.
C28000 vs C66900: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all copper alloy grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all copper alloy grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Bulk Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 105 GPa15.2 Msi · Shear Modulus 39 GPa5.7 Msi
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Max Service Temperature (continuous)
Min Service Temperature
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Castability
Brazeability / Solderability
Polishability
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
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.
Manufacturing and finishing
| Capability | C28000 | C66900 |
|---|---|---|
| CNC machining | Yes | — |
| Sheet metal | Yes | — |
| Default condition | O | — |
| Relative cost | $$$ Premium | $$$$ High |
| Min. machined wall | 0.8 mm | — |
| Best machined surface | Ra 1.6 µm | — |
| Chrome Plating | Yes | — |
| Electropolishing | Yes | — |
| Nickel Plating | Yes | — |
| Painting | Yes | — |
| Tin Plating | Yes | — |
They share 4 finishes: Copper Plating, Electroless Nickel (EN), Gold Plating, Silver Plating.
C28000 vs C66900 — frequently asked
Is C66900 stronger than C28000?
Yes. C66900 has a typical yield strength of 565 MPa (81.9 ksi) against 145 MPa (21 ksi) for C28000 — about 3.9 times as much. Tensile strength is 700 MPa (102 ksi) vs 372 MPa (54 ksi).
Which is cheaper, C28000 or C66900?
C28000 is the lower-cost material: it sits in the premium tier ($$$) while C66900 is high ($$$$). 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, C28000 or C66900?
C28000. Its machinability rates good (55/100) against poor (30/100) for C66900; for welding the order is C28000 first (fair, 50/100) then C66900 (fair, 40/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in C28000 and C66900 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.