This process is a completely chromium-free anti-corrosion process, which can significantly improve the corrosion resistance of the workpiece. It is widely used in zinc die-casting, electro-galvanized hot-dip galvanizing, zinc flakes and other processes, and can achieve a completely chromium-free effect. Improve the anti-corrosion function of the coating, the salt spray performance is higher than that of trivalent chromium plus sealing, does not contain metallic chromium, does not contain harmful chemicals and heavy metals, the film layer is very thin, less than 1 μm thick, transparent in color, and has a strong self- repair ability.