Abstract:
Superhydrophobic materials have broad application prospects in anti-condensation and anti-pollution flashover of electrical equipment for their excellent hydrophobicity and self-cleaning performance. However, the mechanism of power-frequency pollution flashover of superhydrophobic coatings is still unclear. This article presents the incorporation of low surface energy modified nano-SiO2 into epoxy resin, followed by its solidification onto the substrate surface to fabricate an epoxy-based superhydrophobic coating. The power-frequency pollution flashover test of the superhydrophobic coating is carried out under condensation conditions. In combination with the movement behavior of water droplets on the coating surface during the flashover process, the differences in the pollution flashover process of the superhydrophobic coating under different pollution levels are analyzed mechanically. The results show that when nano-SiO
2 is 60wt%, the contact angle and rolling angle of the coating are 160.4° and 3.3° respectively, which has good superhydrophobic property and wear resistance. During the pollution flashover process of superhydrophobic coatings, surface water droplets adhere to the pollution and form liquid marbles, leading to an increase in frictional force on the movement of water droplets. The retention of a large number of stained water droplets is the main reason for the decrease in coating flashover voltage. The results of the pollution flashover test indicate that under the same conditions, the superhydrophobic coating has lower discharge current and higher flashover voltage compared to RTV coating and typical epoxy resin board.