The function of the brightening process in the galvanizing process is to improve the appearance and corrosion resistance of the final product. It removes surface impurities and oxides, improves adherence of the zinc coating to the substrate, and enhances the reflectivity and brightness of the surface. The result is a smooth, shiny surface that is more resistant to tarnishing and corrosion. 

The brightening process in the galvanizing process serves several functions, including improving the appearance of the final product, enhancing its corrosion resistance, and improving its adhesion to the substrate. During the brightening process, the surface of the substrate is cleaned and treated with various chemicals to remove impurities, oxides, and other surface contaminants. This helps to create a more uniform and smooth surface that is better able to accept the zinc coating and provide a higher level of corrosion resistance. Additionally, the brightening process can improve the reflectivity and brightness of the surface, creating a more aesthetically pleasing final product. Overall, the brightening process is an essential part of the galvanizing process that helps to ensure a high-quality, durable coating that is both functional and attractive.