CFRP (Carbon Fiber Reinforced Polymer) vs.
Aluminum is a common comparison in aerospace, automotive, and other high-performance engineering applications. Here’s a detailed breakdown:
1. Material Properties
| Property |
CFRP (Carbon Fiber) |
Aluminum (e.g., 6061, 7075) |
| Density |
~1.6 g/cm? |
~2.7 g/cm? |
| Tensile Strength |
~500–1500 MPa (directional) |
~290–570 MPa |
| Stiffness (Modulus) |
~70–150 GPa (anisotropic) |
~69–80 GPa (isotropic) |
| Fatigue Resistance |
Very good |
Moderate |
| Corrosion Resistance |
Excellent (non-metallic) |
Good (can oxidize, but manageable) |
| Thermal Conductivity |
Low (~5–10 W/m·K) |
High (~120–220 W/m·K) |
| Thermal Expansion |
Very low (near zero) |
Relatively high (~23 ?m/m·K for 6061) |
? 2. Usage in Aerospace
| Use Case |
CFRP |
Aluminum |
| Aircraft Bodies |
Modern aircraft (e.g., Boeing 787, Airbus A350) |
Older gen aircraft (e.g., Boeing 737, A320) |
| Wings/Fuselage |
Superior strength-to-weight ratio |
Easier to fabricate and repair |
| Satellites/Space |
Widely used due to low weight and no corrosion |
Used with surface treatments |
? 3. Manufacturing Cost
| Factor |
CFRP |
Aluminum |
| Manufacturing |
Complex layup, curing, autoclaves often needed |
Simple casting, forging, machining |
| Repairability |
Difficult, needs specialist tools and skills |
Easy to weld, rivet, replace |
| Cost |
Much more expensive (5–20× aluminum) |
Relatively cheap and widely available |
4. Summary: When to Use What
| Situation |
Preferred Material |
| Max weight savings needed |
CFRP |
| Simple, cost-effective solution |
Aluminum |
| High-temperature environments |
Aluminum (CFRP degrades) |
| Custom, performance-optimized |
CFRP |
| Ease of fabrication/repair |
Aluminum |
