The research of space charge and AC aging on alumina/epoxy resin composites

The generation, accumulation, migration and dissipation of the space charge may influence the properties of dielectric largely. In order to study the effect of particle diameters and contents on space charge in epoxy resin composites, micro- and nano- Al₂O₃/epoxy resin composites were prepared in laboratory by adding Al₂O₃ particles into epoxy matrix material. The space charge measurement was performed on both kinds of samples and neat epoxy resin based on pulsed electro-acoustic (PEA) method before and after AC aging. It was found that before AC aging, more space charge was accumulated in micro-composites and nano-composites compared with neat epoxy resin when under 3 kV/mm and 10 kV/mm. And the amount of space charge in Al₂O₃/epoxy resin composites increased with the increasing of Al₂O₃ content. After the AC aging, it was found that the aging resistance of nano-composites was stronger than that of neat epoxy and micro-composites.