What is galvanisation?

What is galvanisation?

• A. Applying a thin zinc coat to protect metal
• B. Coating metal with copper
• C. Coating with nickel
• D. Heat-treating metal to increase hardness

Answer: (B)

Galvanisation is coating metal, usually iron or steel, with zinc to protect it from corrosion. The zinc layer acts as a barrier to moisture and oxygen, and because zinc is more reactive than the metal underneath, any damage that exposes the metal will still be protected—zinc will corrode first, shielding the iron or steel beneath. This combination of barrier protection and sacrificial protection makes galvanised metal last much longer in harsh environments. It’s commonly done by dipping the metal in molten zinc (hot-dip galvanizing), though electroplating zinc is another method. Other coatings like copper or nickel, or processes like heat-treating, are different treatments and not galvanising.

Galvanisation is coating metal, usually iron or steel, with zinc to protect it from corrosion. The zinc layer acts as a barrier to moisture and oxygen, and because zinc is more reactive than the metal underneath, any damage that exposes the metal will still be protected—zinc will corrode first, shielding the iron or steel beneath. This combination of barrier protection and sacrificial protection makes galvanised metal last much longer in harsh environments. It’s commonly done by dipping the metal in molten zinc (hot-dip galvanizing), though electroplating zinc is another method. Other coatings like copper or nickel, or processes like heat-treating, are different treatments and not galvanising.