The effects of accelerator, fluoride, Mn2+, Ni2+, Zn2+, PO4 and Fe2+ on the phosphating process of aluminum were studied by SEM, XRD, potential-time curve and membrane weight change. Studies have shown that cerium nitrate has the characteristics of good water solubility, low dosage and rapid film formation, and is an effective accelerator for phosphating of aluminum. Fluoride can promote film formation, increase film weight and refine grains; Mn2+ and Ni2+ can refine grains, make phosphating film uniform and dense and improve the appearance of phosphating film; when Zn2+ concentration is low, film can not be formed Or the film formation is poor, with the increase of Zn2+ concentration, the membrane weight increases; PO4 content has a greater impact on the phosphating film and increases PO4. The content causes the phosphating film to increase in weight.
Aluminum alkaline electropolishing process
The research on the alkaline polishing solution system was carried out, and the effects of corrosion inhibitors and viscosity agents on the polishing effect were compared. The alkaline solution system with good polishing effect was successfully obtained, and the operating temperature and the extended solution were obtained for the first time. An additive that has a long life and an improved polishing effect. The experimental results show that adding a suitable additive to the NaOH solution can produce a good polishing effect. Exploratory experiments also found that the surface reflectance of aluminum can reach 90% after DC constant pressure electropolishing with NaOH solution of glucose under certain conditions, but there are still unstable factors in the experiment, which needs further study. The feasibility of using DC pulse electropolishing method to polish aluminum under alkaline conditions was explored. The results show that the pulse electrolysis polishing method can achieve the leveling effect of DC constant pressure electropolishing, but its flattening speed is slow.
Aluminum and aluminum alloy environmentally friendly chemical polishing
It is determined to develop a new environmentally friendly chemical polishing technology based on phosphoric acid monosulfate, which is to achieve zero emission of NOx and overcome the quality defects of similar technologies in the past. The key to the new technology is to add some special-effect compounds to the base fluid instead of nitric acid.