Galvanised Steel

Galvanised steel sheet is carbon steel coated with a protective layer of zinc. The zinc helps protect the underlying steel from corrosion, making galvanised sheet suitable for manufacturing, construction, ductwork, enclosures and general fabrication. Matrix Steel supplies galvanised steel sheet to trade and public customers throughout the UK and Ireland.

The zinc coating creates a barrier between the steel and the surrounding environment. It also provides sacrificial protection, meaning the zinc corrodes preferentially to help protect exposed steel at minor scratches and cut edges. The service life will depend on the coating thickness, environment, fabrication and ongoing exposure to moisture or chemicals.

Common applications include ducting, roofing components, cable trays, cabinets, enclosures, agricultural equipment, automotive parts, pressed components and general manufacturing. Its corrosion resistance makes it particularly useful for components exposed to moisture or environments where uncoated mild steel would require additional protection.

Hot rolled steel is normally supplied with an uncoated mill-scale surface, whereas galvanised steel has a protective zinc coating. Hot rolled steel is commonly selected for structural and heavy fabrication work. Galvanised sheet is often preferred for lighter manufactured components that require improved corrosion resistance without painting immediately after production.

Galvanised steel can be welded, but the zinc coating affects the welding process and produces hazardous zinc-oxide fumes when heated. Appropriate extraction, ventilation, personal protective equipment and a suitable welding procedure are essential. The weld area may also require cleaning and renewed corrosion protection after welding.

Galvanised steel provides significantly better corrosion resistance than untreated mild steel, but it is not completely rustproof. Corrosion can eventually occur if the zinc coating is damaged, consumed over time or exposed to particularly aggressive conditions. Cut edges and welded areas may require additional protection depending on the intended environment.