HIGH TEMPERATURE, NON-REFLECTIVE EROSION RESISTANT ALUMINUM FINISH

A number of soluble inorganic compounds were used in reactions to deposit insoluble colored precipitates pigments in the pores of anodized aluminum alloys. Many colors and shades were obtained by using the variables of time of immersion, temperature and concentrations of the coloring solutions. The effects of the alloying constituents were observable in the colors obtained. There is a notable scarcity of inorganic compounds which can be used to produce a black or olive drab color on anodized aluminum. Alundum blasting improves variability and depth of colors. By proper control of the hard anodize process, excellent shades of light-fast, nonreflective olive drab colors can be produced.