Solar Absorbing Surfaces of Anodized Dendritic Tungsten
by G. D. Pettit, J. J. Cuomo, T. H. DiStefano, J. M. Woodall
Anodization of textured tungsten is shown to have merit either in creating a solar absorber of extremely high absorptance when applied to a large dendritic surface, or in enhancing the solar absorptance-to-emittance ratio when applied to smaller hillock topographies. The angular dependence of the absorption is reduced by the anodization coating, which consists of a thin conformal coating of WO3. The surface is stable up to temperatures of 520 K in air.