Preparation of Heat Resistant Coatings with Low Infrared Emissivity and Mechanism

Low infrared emissivity coatings working at high temperature were obtained by using silicone resin and leafing aluminum as adhesives and paint,respectively.The effect of solidification temperature and the concentrations of leafing aluminum on emissivity was studied.The surface morphology and infrared emissivity of the as prepared coatings were investigated,and the heat resistant measurement was also performed.The results indicate that the infrared emissivity(3~5μm,8~14μm) of the coatings with 30% leafing aluminum can reach 0.10~0.12,and the coa-tings can work at 600℃ for a long time.It is thought that the reducing infrared absorption of adhesives as well as the formation of dense continuoust laminar aluminium structure may account for the lower emissivity of coatings,besides a new model of coating structure is proposed to illustrate the low emissivity mechanism.