Galvanizing protects steel and iron through different methods:
Barrier Protection: Firstly, the zinc acts as a barrier or physical shield to protect the material from moisture and air.
Sacrificial Protection: It also acts as a sacrificial anode, meaning it corrodes preferentially to protect the steel.
Zinc Carbonate Formation: Lastly, the zinc reacts with oxygen, moisture, and eventually carbon dioxide over time to form a hard coat called zinc carbonate (or more precisely, basic zinc carbonate).
Galvanizing is not the same as simply coating the material with paint, as some may think. While zinc protects in more ways, it is not completely immune to corrosion; it corrodes slowly and sacrificially to protect the underlying steel. Certain environmental factors can still degrade the performance.
