Improvement of Hydrophobicity of Ceramics by AR/PDMS Dielectric Barrier Discharge Under Parameterized Nanosecond Pulsed Excitation

Ceramic is widely used in power systems as insulation devices, but flashover always happens especially under rainy weather and humid environment. Improving surface hydrophobicity of ceramic surface can enhance its anti-flashover capability. In this paper, we propose to fabricate super-hydrophobic ceramic surface by Ar/PDMS dielectric barrier discharge using a nanosecond pulse source. The discharge characteristics diagnosis and water contact angle measurement were carried out under different voltage amplitudes, repetition frequencies, rising edge time and pulse width. The influence of source parameters on discharge intensity and particle activity was obtained, and the relationships between source parameters and water contact angle were established. The results show that increasing the voltage amplitude can strengthen the discharge intensity, and improve surface hydrophobicity. The repetition frequency shows the most distinguished effect on the treatment, and super-hydrophobic surface can not be achieved when it is lower than 2 kHz. The pulse width has no significant effect on the preparation effect, while proper rising time is necessary. When the pulse amplitude is greater than 10kV, the repetition rate is in the range of 2k ~ 5kHz, and the rise time is in the range of 100 ~ 200ns, the super-hydrophobic ceramic surface can be prepared after treatment for 120s.