Fiber comparison
E-glass fiber vs Carbon fiber (IM7)
Every value below is a typical room-temperature figure with its source, test method and conditions — the same dataset that drives the calculators.
| Property | E-glass fiber | Carbon fiber (IM7) | Difference |
|---|---|---|---|
| Density | 2.54 g/cm³ | 1.78 g/cm³ | E-glass fiber — 43% higher |
| Young's modulus E | 72.4 GPa | 276 GPa | Carbon fiber (IM7) — 3.8× higher |
| Tensile strength | 3450 MPa | 5516 MPa | Carbon fiber (IM7) — 60% higher |
Where these numbers come from
- Daniel & Ishai, Engineering Mechanics of Composite Materials, 2nd ed.
- Hexcel HexTow carbon fiber product datasheet
Typical room-temperature values for learning and preliminary design; grades vary widely and a supplier datasheet always overrides a textbook figure. Confirm against the datasheet before design work.