Design and 3D Printing of Ceramic Insulation for Surface Flashover Mitigation in Vacuum

Poor electrical strength of the ceramic–vacuum interface restricts the development of various electrical/electronic devices. Limitations of solutions based on conventional ceramics fabrication procedures are becoming prominent with the further demand for compactness and performance improvement. In this study, a fabrication method utilising 3D printing technology is proposed to construct ceramic insulation with designed structures. The processing characteristics, dielectric properties and morphologies of 3D-printed ceramics fabricated under different processing parameters were analysed. The results indicated that fillers' particle size, sintering temperature and sintering aids have significant influence on the dielectric properties and the internal defects. Finally, with optimised processing parameters, Al₂O₃ ceramics with low dielectric loss and complex structures were fabricated to inhibit vacuum flashover from the perspectives of electric field optimisation and secondary electron emission suppression. Compared with traditional ceramic insulator fabrication methods, the proposed construction strategy has an accurate and efficient fabrication process and high insulation performance, making it promising for industrial applications.