Comparison of Ceramic Insulation Coatings via Impedance Spectroscopy

Abstract Alumina is often used for electrical insulation. However, different material systems promise to increase the insulation due their characteristics. Because of process properties including high cooling rates, thermally sprayed coatings generally differ from sintered material, which also effect properties. Within this study, are analyzed via impedance spectroscopy evaluate capacitive and behavior. Besides comparing frequency-dependent resistance, equivalent circuit diagrams were calculate relative permittivity coatings. X-ray diffractograms reveal phase stability during thermal spraying. diffraction was additionally conducted classify respective effects. In particular, investigated mullite-based exhibit slightly increased values compared conventionally alumina-based coating systems.