Estimation of the volume resistivity of conductive fiber composites by two new models

Existing models often do not accurately predict composite conductivity, as composite microstructure is generally neglected. Two models are proposed which predict the volume resistivity of a composite using microstructural data. The first model assumes perfect fiber-fiber contact, and relates resistivity to the concentration aad orientation of the fibers. The second model accounts for the effect of fiber-fiber contact and fiber length on composite resistivity. Predictions from both models are compared to experimental data for nickel-coated graphite fiber-polypropylene composites. The relationship between resistivity and fiber orientation predicted by the first model compares well with experimental results. Predictions from the second model are in excellent agreement with experimental data.