Effect of Surface Status on the Corrosion Resistance of 6061 Aluminum Alloy

Objective To investigate the corrosion behaviour of 6061 aluminum alloy in conditions of different temperatures and surface roughness and the enhancement of corrosion resistance of the alloy by using surface sulphuric acid anodizing and boracic-sulphuric acid anodizing. Methods The salt spray tests and the electrochemical experiments were conducted on samples. Results The corrosion resistance of the alloy increased along with the decrease of the surface roughness, the deposited salt particles on the alloy surface reduced remarkably and the corrosion area decreased as the surface anodized. In addition, the alloy corrosion resistance decreased as the temperature raised, but the samples were passivated when the temperature reached 55 ℃, and the passivation resolved and the corrosion rate raised again as the temperature raised continuously. Conclusion The results show that the corrosion resistance of 6061 aluminum alloy decreases as the surface roughness and the temperature rise, and 55 ℃ is a proper passivation temperature for 6061 aluminum alloy.