METHOD FOR COLORING TITANIUM AND TITANIUM ALLOY

摘要

PURPOSE:To grow an attractive anodic oxidation coating and to color titanium by subjecting a titanium metal to a combination of heat treatment and chemical polishing to grow a bright fine crystalline grain pattern at the titanium surface and then carrying out anodic oxidation. CONSTITUTION:Heat treatment is applied to a titanium material at about 825-1000 deg.C for several - several tens minuies, by which microcrystals are grown in the titanium metal. Subsequently, the titanium material is treated with a chemical polishing solution, and, as to the composition of this chemical polishing solution, a commercial mixed solution of phosphoric acid, acetic acid, and hydrofluoric acid and a mixed solution in which the ratio of hydrofluoric acid to hydrogen peroxide solution is regulated to 1 to = about 7 are successively used. By the above procedure, the titanium surface can be uniformized, and also impurities can be removed. By this method, the uniform and bright surface having fine crystalline grain pattern, not noticeably showing soil due to fingerprints, etc., and also having superior property is formed. Then, anodic oxidation is exerted to form a high quality anodic oxidation coating.