Fractal Evaluation on Effective Dielectric Properties for High-Velocity Oxygen Fuel Sprayed LBS-SiCβ Composite Absorber Coatings

An evaluation of microstructure-property relationship is important for thermally sprayed composite absorber coatings, because self-similarity in the microstructure is a key characteristic that can affect coating properties, such as flattened particle shape, pores, absorbent phase, and coating thickness. In this paper, a multiscale effective fractal model is reported to characterize the microstructure-property relationship for high-velocity oxygen fuel (HVOF) sprayed composite coatings. It shows the fractal of coating structure was presented to calculate the volume fraction of thermally sprayed absorber coatings with wavelet-fractal algorithm. As an example, the flattened particle shape, porosity, and thickness were researched for the microwave reflectivity coefficient of HVOF sprayed nanometer LBS (Li2O-B2O3-SiO2)-SiC beta composite coatings. The modeling approaches to establishing the relationships between coating microstructure and absorbing property was checked.