ИСПОЛЬЗОВАНИЕ ИМПЕДАНСНОЙ СПЕКТРОСКОПИИ ДЛЯ ОПРЕДЕЛЕНИЯ ВЛИЯНИЯ ОБЪЕМНОЙ КОНЦЕНТРАЦИИ ПИГМЕНТА НА СТРУКТУРНЫЕ СВОЙСТВА ЭПОКСИДНОГО ПОКРЫТИЯ

Epoxy coatings containing different concentration of quartz pigment on steel substrate were studied by EIS. Equivalent circuits were offered for approximation of experimental EIS spectra. Relationship of equivalent circuits’ elements with fractal dimension of percolation clasters formed at electrolyte penetration along coatings imperfections was obtained. Two types of percolation structures were revealed: one of them referring to binder imperfections, the other concerning with defects on the boundaries between binder and pigment’s particles. Three critical concentrations of pigment were found. The value of the last has coincided with critical volume concentration of pigment estimated by independent method.