Copper-Clad Aluminum (CCA) is a bimetallic conductor consisting of an aluminum core metallurgically bonded with a continuous outer layer of copper. This design combines copper’s surface conductivity, corrosion resistance, and solderability with aluminum’s low density and cost efficiency.
CCA is widely used in applications where weight reduction and material cost savings are critical, while still maintaining acceptable electrical performance.
Structural Composition
| Component | Typical % (by volume) |
|---|---|
| Aluminum Core (Al) | 85 – 90% |
| Copper Cladding (Cu) | 10 – 15% |
Note:
CCA is defined by its layered structure, not by alloying.
Key Physical Properties
| Property | Typical Value |
|---|---|
| Density | ~3.3 – 3.6 g/cm³ |
| Melting Point | Al: ~660°C / Cu: 1085°C |
| Electrical Conductivity | 55 – 68% IACS |
| Thermal Conductivity | ~200 – 235 W/m·K |
| Coefficient of Expansion | ~23 × 10⁻⁶ /°C |
| Magnetic Behavior | Non-magnetic |
| Weight vs Copper | ~40% lighter |
Key Mechanical Properties
| Property | Typical Range |
|---|---|
| Tensile Strength | 150 – 250 MPa |
| Yield Strength | 60 – 150 MPa |
| Elongation | 10 – 25% |
| Hardness | 30 – 60 HV |
| Fatigue Resistance | Moderate |
Mechanical behavior is closer to aluminum than copper and varies with copper thickness, conductor size, and annealing condition.
Strengthening & Metallurgical Behavior
✔ Aluminum core and copper cladding remain separate phases
✔ Bond achieved by solid-state metallurgical welding
✔ Strength increased only through cold working (drawing)
✔ No precipitation or age hardening possible
Important:
CCA performance depends on geometry and bonding quality,
not on alloy-based strengthening.
Key Characteristics of Copper-Clad Aluminum
✔ Lightweight conductor
✔ Good surface conductivity
✔ Copper-like termination and soldering behavior
✔ Improved corrosion resistance vs bare aluminum
✔ Lower cost than solid copper
✔ Non-magnetic
✔ Effective for high-frequency applications (skin effect)
Limitations:
Lower ampacity than pure copper
Lower mechanical strength
Not ideal for vibration or repeated flexing
Refining & Processing Properties
✔ Aluminum rod preparation
✔ Copper tube or strip cladding
✔ Bonding by roll bonding, extrusion bonding, or continuous welding
✔ Wire drawing and annealing
✔ Scalable mass production
✔ Consistent cladding thickness
✔ Economical manufacturing
Available Forms
Round wire
Stranded wire
Coaxial cable conductors
Power and signal cables
Magnet wire (specialized)
Size range: AWG 40 to large stranded conductors
Applications of Copper-Clad Aluminum
Telecommunications
Coaxial cables
LAN and RF cables
Antenna conductors
Electrical & Electronics
Consumer appliance wiring
Speaker cables
Non-critical power cords
Automotive
Signal wiring
Lightweight wiring harnesses
HVAC & Equipment
Control wiring
Internal equipment wiring
Renewable & Consumer Products
LED lighting
Solar balance-of-system wiring
Advantages of Copper-Clad Aluminum
✔ 30–40% weight reduction
✔ 20–50% material cost savings vs copper
✔ Copper-compatible connectors
✔ Good corrosion resistance
✔ Acceptable conductivity for many applications
✔ Easier handling than aluminum
Why Choose Copper-Clad Aluminum?
Choose CCA when you require lower cost, reduced weight, copper-like surface behavior, good high-frequency performance, and large-volume, cost-sensitive production.
Engineering Recommendation:
CCA is ideal for signal and RF applications,
but not recommended for high-current or safety-critical power systems.
Comparison with Copper & Aluminum
| Property | CCA | Pure Copper | Aluminum |
|---|---|---|---|
| Conductivity | ★★★ | ★★★★★ | ★★★ |
| Weight | ★★★★★ | ★★ | ★★★★★ |
| Cost | ★★★★ | ★★ | ★★★★★ |
| Solderability | ★★★★ | ★★★★★ | ★★ |
| Mechanical Strength | ★★★ | ★★★★ | ★★★ |
| Ampacity | ★★★ | ★★★★★ | ★★★ |
Sustainability & Lifecycle
✔ Reduced copper consumption
✔ Lower mining and environmental impact
✔ Recyclable (requires material separation)
✔ Lower transportation emissions due to reduced weight