Estimate equivalent composite properties such as density and modulus as volume-fraction weighted averages of the constituents.
| Item | Formula / Note | Source / Standard |
|---|---|---|
| Longitudinal modulus (iso-strain) | E_c = E_f · V_f + E_m · ( 1 - V_f ), where V_f is the fibre volume fraction | Rule of mixtures; Jones RM, Mechanics of Composite Materials, CRC Press |
| Transverse modulus (iso-stress) | 1/E_c = V_f/E_f + ( 1 - V_f )/E_m (inverse rule of mixtures) | Jones RM, Mechanics of Composite Materials, CRC Press |
| Density | rho_c = rho_f · V_f + rho_m · ( 1 - V_f ), weighted by volume fraction | Jones RM, Mechanics of Composite Materials |
| Bounds | The iso-strain and iso-stress models give the upper and lower bounds of the modulus | Jones RM, Mechanics of Composite Materials |