Research on the microwave heating and de-icing performance of various composite coatings

Abstract Microwave heating and de-icing is an efficient, eco-friendly choice for wind turbine blade de-icing methods, where microwave energy is converted into heat through absorbing coatings. Thus, the heating characteristics of absorbing coatings under microwave irradiation are of paramount importance. In this paper, 15 types of polyurethane composite coatings containing different absorbing fillers were prepared, and their heating performance under 2.45 GHz microwave irradiation was investigated. The effects of filler type, filler content and irradiation distance on heating rate were systematically evaluated, and the de-icing performance of various ice layer thicknesses was analyzed. Results revealed that ferroferric oxide/polyurethane coatings with an identical filler content exhibited the fastest heating rate, followed by graphite/polyurethane and silicon carbide/polyurethane. The heating characteristics of the coatings were positively correlated with filler content and negatively correlated with irradiation distance. As ice thickness increased, so did the time for ice shedding and melting. Composite coatings demonstrated superior de-icing performance compared with control specimens, creating a central melting region that gradually expanded to melt the entire ice layer.