Aramid fibre vs Carbon fibre
Aramid fibre and Carbon fibre are genuine alternatives to one another — a choice somebody actually makes — and differ on 2 measured properties, density most clearly.
Aramid fibre vs Carbon fibre
Aramid fibre
Rigid rod molecules lined up along a fibre — five times the strength of steel by weight, and the material of body armour.
Carbon fibre
Filaments of near-pure carbon with extraordinary stiffness-to-weight, used in composites rather than alone.
| Property | Aramid fibre | Carbon fibre |
|---|---|---|
| Density | 1.39–1.45 g/cm³ | 1.75–1.95 g/cm³ higher |
| Tensile strength | 2900–3600 MPa | 3500–7000 MPa higher |
| Young's modulus Only one of the two has a figure we can stand behind, so there is nothing to compare. | 70–120 GPa | Not known |
Choosing between them
Aramid fibre is recorded as a substitute for Carbon fibre — stronger.
What it gives up: Fails in compression by kinking rather than breaking, so an aramid laminate is poor in compression and bending — which is why the two are usually hybridised rather than chosen between.
In this application, on the evidence cited above.