Surface-modified CeO2 coating with excellent thermal shock resistance performance and low infrared emissivity at high-temperature

The CeO2 filler modified by different content (0, 1, 5 and 10 wt%) of polyethylene glycol (PEG) 400 and the inorganic silicate binder were introduced for preparation of coatings with excellent thermal shock resistance performance and low infrared emissivity at high-temperature. The influences of PEG 400 content on phase structure and morphology of CeO2 powders, and hence on thermal shock resistance behavior and high-temperature infrared emissivity of the corresponding coatings were investigated deeply in this work. The results show that the crystal structure of CeO2 remains unchanged after modification of PEG 400. The dispersity of CeO2 particles is improved with content of modifier PEG 400 increasing from 0 wt% to 5 wt% while it gets worse with PEG 400 content further rising to 10 wt%. Thermal shock resistance of the corresponding coatings enhances from 4 cycles to 31 cycles by increasing PEG 400 content from 0 wt% to 5 wt% while diminishes significantly to 1 cycle with PEG 400 content of 10 wt%. Simultaneously, the minimum emissivity of 0.348 is achieved at 600 degrees C in the coating with 5 wt% of PEG 400. The results suggest that the coating with CeO2 modified by 5 wt% of PEG 400 is a promising candidate for high-temperature infrared stealth due to both excellent thermal shock resistance and low infrared emissivity at high temperature.