E-glass fiber vs Flax fiber (natural)

Every value below is a typical room-temperature figure with its source, test method and conditions — the same dataset that drives the calculators.

E-glass fiber in fullFlax fiber (natural) in full← All materials
PropertyE-glass fiberFlax fiber (natural)Difference
Density2.54 g/cm³1.5 g/cm³E-glass fiber — 69% higher
Young's modulus E72.4 GPa58 GPaE-glass fiber — 25% higher
Tensile strength3450 MPa800 MPaE-glass fiber — 4.3× higher
  • Daniel & Ishai, Engineering Mechanics of Composite Materials, 2nd ed.
  • Pickering, Efendy & Le, Composites Part A 83 (2016) — natural fibre review

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.