In automotive technology, the proper use of thermal insulation materials helps improve the performance and life of internal equipment and reduce maintenance cost. In this study, plasma spraying and flame spraying are used to prepare and coat a new MgO-B2O3-SiO2-Zn powder on the SUS304 substrate. The resulting coating as thermal insulation layer formed a networked microstructure between the substrates to improve the thermal insulation performance of the material. By validation of thermal radiation experiments, the thermal insulation effects of various ceramic powders were compared, the high-temperature and low-temperature thermal insulation materials for about 300 and 100 °C were determined, and the thermal insulation performance of the constructed material coatings was verified by analysis.

This article focuses on the microstructure and mechanism analysis of the novel coating MgO– B2O3–SiO2–Zn prepared by plasma spraying and flame spraying on the SUS304 alloy substrate. Firstly, the crystal compositions of the powders were analyzed by XRD (X-ray diffraction). Secondly, the surface and cross section microstructures of the coating were observed by SEM (Scanning Electron Microscope) and EPMA (electron probe microanalysis) in order to study the mechanism of the thermal insulation performance. It is concluded that, the microstructure, different thickness and compositions have various effect on heat insulation.