The development of alumina formed on aluminum using phosphoric acid anodizing technique

In this study, development of surface oxide formed on aluminium in 0,5 M phosphoric acid electrolyt under various anodizing conditions (temperature, voltage, anodizing time) was investigated. Using electrochemical techniques corrosion behavior of surface oxide formed on aluminium was investigated in 0,2 M Na2SO4 and % 3,5 NaCl solutions. Also in these solutions polarization resistance is measured and current-voltage curves are plotted. The influences of applied voltages, coatings times and temparatures on the protective effect of alumina formed on aluminium was searched. When EIS diyagrams and current-voltage curves were examined, protective effect of coatings that immersed in 0,2 M Na2SO4 solution for 4 hours is more better than samples that immersed in %3,5 NaCl solution for 2 hours. Key Words: Corrosion, Alüminium, Anodizing.