Charge decay characteristics of ATH/epoxy composites

Though the electrical insulation properties of epoxy resin are very excellent, the surface of epoxy insulator is charged easily and the charge is hard to decay. When the charge density accumulates to a level, it would lead to a part discharge or a surface flashover. In order to improve the surface flashover voltage of epoxy resin, ATH inorganic fillers with 1m particle size are used to change the surface properties of the epoxy resin. Samples with different mass fraction ATH fillers are prepared, which are 0% (pure epoxy), 20%, 40%, 60%, 80% and 100%. The pulsed electro-acoustic method is employed to study charge decay properties of epoxy composites. Several kinds of composites are experimented after the application of 10 kV/mm or 30 kV/mm polarization electrical field respectively. The results show that the charge decay constant of epoxy composites is related to the inorganic fillers mass fraction of the epoxy resin and the charge quantities of the samples.