Galvinasing iron

• Galvanising is one of the methods used to prevent iron from rusting
• Iron and steel can be coated with zinc
• Zinc is a fairly more reactive metal
• This means it will corrode before the iron does
• This is also known as sacrificial plating
• Even when the metal underneath (iron/steel) is exposed the zinc will corrode instead of thus protecting the iron
• Zinc plating is also called galvanizing
• It is usually used for small items such as nuts and bolts
• It is also used on large items such as iron roofing sheets
• Steel is used to make the galvanised roofing sheets
• Steel sheets are cleaned first
• They are then passed through molten zinc
• An alloy of zinc and iron then forms on the surface of the steel sheets
• The zinc in the galvanised iron sheets prevents the sheets from rusting
• Zinc is more reactive than iron thus it will corrode first
• Even if the iron is exposed to the atmosphere
• This method is used to make corrugated roofing sheets which are widely used in Zimbabwe

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