Partial Discharge Erosion on Gamma-Ray Irradiated Epoxy/Al2O3 Nanocomposites

Abstract

In this paper, epoxy based nanocomposites with Al2O3as filler have been prepared to study the influence of gamma-irradiation on its partial discharge erosion behavior. The filler content was selected at 1 wt%, 3 wt% and 5 wt%, respectively. A Cobalt-60 gamma source was employed for the irradiation treatment with the doses up to 1000 kGy. Partial discharge erosion was attained by a pair of rod-plane electrode. Simultaneously, a 3D surface profiler was used to detect the erosion morphology. In order to have a more comprehensive understanding of the radiation effect on the epoxy sample, isothermal surface potential decay and differential scanning calorimetry have been measured to obtain the Tg and trap distribution features. Test results indicated that the maximum erosion depth appeared to decrease firstly and tended to increase afterward with the sample exposed from 0 kGy to 1000 kGy. The addition of nano-Al2O3 had a positive effect on modifying the resistance to partial discharge of epoxy resin irrespective of the irradiation dose, and 3 wt% of nano-Al-O, addition contributed to the smallest erosion depth among all the nanocomposites. It is suggested that the partial discharge erosion on the nanocomposites is varied since the chemical reaction induced by radiation depends on the radiation dose. Deeper trap leads to better resistance to the discharge erosion.