PROCESS FOR FORMING A SELECTIVE ABSORPTION LAYER ON AN ALUMINUM SURFACE

摘要

A solar collector panel absorbing incident solar energy at a high rate while radiating only a small portion of the absorbed energy comprises aluminum or an aluminum alloy as a continuous metallic substrate carrying an anodized oxide layer not substantially thicker than 1 mu . The exposed anodized surface is formed with a multiplicity of pores receiving nickel rods of microscopic dimensions which project from the oxide surface. When the pores are spaced apart 0.1 to 1 mu and have a diameter of 0.1 to 0.5 mu , the nickel rods being dimensioned correspondingly, the panel has the desired properties.