Surface treatment of aluminium products

Surface treatment of aluminium products

Oxidation process sulphuric acid method, oxalic acid method, chromic acid method oxidation process, especially the sulphuric acid anodic oxidation method for almost everyone engaged in the surface treatment of aluminium products without familiar.

These oxidation methods have their own characteristics and scope of application, such as oxalic acid method, can obtain a thicker oxide film layer, the oxide film itself with some decorative colours, but the method is costly, consuming large amounts of electricity. The sulphuric acid method has a transparent and colourless oxide layer, with good colour absorption properties, plus a simple and stable electrolyte composition, easy operation and low cost, so it is more widely used. However, the temperature control range of the sulphuric acid method is small and the temperature rises quickly, so it is often necessary to install refrigeration equipment, which becomes another difficulty. In Japan, the sulphuric acid-oxalic acid mixed acid oxidation method has long been developed, taking the best of both worlds and avoiding the worst of both worlds, and has become the main oxidation bath solution in Japan.