Quantitative Investigation of the Nonlinear Polarization in Epoxy/SiC Nanocomposite

To investigate the relationship between the nonlinear polarization and the filler concentration in epoxy/SiC nanocomposites, an analytical method based on the asymmetrical double-well model and genetic algorithm (GA) is proposed. The response currents of samples with different filler concentrations are measured under different electric fields. The polarization current is separated from measured current by curve fitting with “universal law.” Further, the polarization is calculated by integrating polarization current. The influence of SiC filler concentration on the nonlinear polarization is studied with the proposed method. The results show that the equivalent distance δ and the asymmetrical degree
$V$
between two wells have a consistent variation with filler concentration. The nonlinear polarization depends on
$V$
more than δ.