The range of zinc coatings

SummaryOver 40 million tonnes of steel are coated with zinc or zinc alloys each year. The most important technique is hot dip galvanizing, which can be applied either to un fabricated sheet or wire, to tube (in automatic plants) or to fabricated articles. Other methods of applying zinc include spraying of the molten metal, sherardizing (involving heat below the melting point of zinc), electroplating, mechanical coating and a wide range of zinc rich paints and products in which zinc dust or flake are added to organic or inorganic media.The combination of metallic zinc coatings with paint, powder or plastics overcoats is both important and expanding because the combined (‘duplex’) coating has a greater life than a simple summation of the lives of the coating layers taken individually.