How Does Galvanising Work?

Hot-dip galvanizing is the process of immersing iron or steel in a bath of molten zinc to produce a corrosion resistant, multi-layered coating of zinc-iron alloy and zinc metal. ... This reaction is a diffusion process, so the coating forms perpendicular to all surfaces creating a uniform thickness throughout the part.

How does Galvanising prevent rust?

Galvanizing protects from rust in a number of ways: It forms a barrier that prevents corrosive substances from reaching the underlying steel or iron. ... The zinc protects its base metal by corroding before iron. The zinc surface reacts with the atmosphere to form a compact, adherent patina that is insoluble in rainwater.

Why do we use zinc for galvanizing?

The reason that the galvanizing process uses zinc instead of other metals is that zinc oxidizes and experiences acid corrosion “sacrificially” to steel. That means that when zinc is in contact with steel, oxygen and acids will attack the zinc rather than the steel beneath it.