Galvanization or galvanizing is the process of applying a protective zinc coating to steel or iron, to prevent rusting. The most common method is hot-dip galvanizing, in which parts are submerged in a bath of molten zinc.

Hot-dip galvanizing deposits a thick, robust layer of zinc iron alloys on the surface of a steel item. In the case of automobile bodies, where additional decorative coatings of paint will be applied, a thinner form of galvanizing is applied by electrogalvanizing.

Galvanising protects the underlying iron or steel in the following main ways:

1. The zinc coating, when intact, prevents corrosive substances from reaching the underlying steel or iron.

2. The zinc serves as a sacrificial anode so that even if the coating is scratched, the exposed steel will still be protected by the remaining zinc.

3. The zinc protects iron by corroding first. For better results, application of chromates over zinc is also seen as an industrial trend.

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