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Produced when hot or cold rolled sheet or strip is coated with zinc, either by the hot-dipping or electrolytic deposition processes. Zinc coating applied by the hot dip method is normally heavy enough to resist corrosion without additional protective coating.
Materials electronically galvanised are not used for corrosion-resistant applications without subsequent chemical treatment and painting, except in mild corrosive conditions, due to the thin coating of zinc. Galvanise is a pure zinc coating. A special heat-treating process converts the pure zinc coating to a zinc/iron alloy coating, and the product is known as Galvanneal.
Applications
Construction (Cladding/Sliding, roofing, building accessories, sliding shutters, doors, partitions, canopies of gas stations, false ceilings, prefabricated buildings, sandwich panels, HVAC(heating, ventilation & air con ducting) etc.), Electrical appliances (Washing Machines, gas ovens, microwave ovens, refrigerators, freezers coolers, elevator, vending machines, grillers, toasters, air conditioners etc.), Automotive (Doors, fenders, heat insulators, air cleaners, air conditioners etc.), Domestic Appliances (Water tanks, trunks, canisters, ducting, water coolers, Ice boxes, geysers, etc.), Others (Containers, packaging, furniture, computer peripherals, road signs, bus body buildings, storage bins, bill boards, etc.).
Hot-dip Galvanizing:
The immersion of iron or steel in molten zinc, after the surface of the base metal has been properly cleaned. This process gives a relatively thick coating of zinc that freezes into a crystalline surface pattern known as spangles. During the process, a multiple layered structure of iron- or steel-zinc alloys is formed between the inner surface of the zinc coating and the iron or steel. These middle layers tend to be hard and brittle and may peel or flake if the iron or steel element is bent.
Electrogalvanizing:
The immersion of iron or steel in an electrolyte, a solution of zinc sulfate or cyanide. Electrolytic action deposits a coating of pure zinc on the surface of the iron or steel.
Sherardizing:
The placing of a thoroughly cleaned iron or steel element in an air-free enclosure where it is surrounded by metallic zinc dust. The architectural element is then heated and a thin, zinc alloy coating is produced.
Metallic Spraying:
The application of a fine spray of molten zinc to a clean iron or steel element. The coating can then be heated and fused with the surface of the iron or steel to produce an alloy.
Painting:
Paint containing zinc dust pigments may be applied as a protective Advantages
