Which surface treatment prevents further corrosion on metals?

The correct answer, acid etch, is a surface treatment process that involves applying an acid solution to promote the bonding of a coating to a metal surface. This technique not only prepares the metal for receiving a protective layer but also creates a roughened profile that enhances adhesion. By applying a suitable protective coating after etching, it effectively seals the metal and prevents moisture and contaminants from initiating corrosion processes.

While gloss paint and top coats can provide a barrier to environmental factors, their primary function is more about aesthetics and providing an additional surface layer rather than directly addressing corrosion prevention through a chemical reaction with the metal. Wax finishes, on the other hand, do provide moisture resistance but are typically less durable than other coatings and can wear off quickly, necessitating frequent reapplication.

Thus, acid etch stands out as a method that not only prepares the surface for additional coatings but also enhances long-term corrosion resistance when combined with the right topcoat.