Zinc coatings prevent oxidation of the protected metal by forming a barrier and by acting as a sacrificial anode if this barrier is damaged. Zinc oxide is a fine white dust that (in contrast to iron oxide) does not cause a breakdown of the substrate's surface integrity as it is formed. Indeed the zinc oxide, if undisturbed, can act as a barrier to further oxidation, in a way similar to the protection afforded to aluminum and stainless steels by their oxide layers. The majority of hardware parts are zinc plated, rather than cadmium plated..inc-flake coatings are sacrificial coatings which contain zinc and/or aluminium elements that oxidize sacrificially to ensure the substrate of to which they are applied remains corrosion free. These coating systems were designed for automotive and industrial parts that require greater protection than what standard paint and other coating systems can supply.
Zinc-flake coatings are used to protect non-flexing or rarely-flexing parts like brake rotors, drums and callipers; brake lines and hose clamps; fuel tanks and filler pipes; mufflers; the underside of hoods; clips, fasteners, springs and stampings; seat belt components and door lock components…and pretty much anything else that comes in contact with the elements and can survive a 450-degree curing cycle. These coatings can also prevent galvanic corrosion as a result of dissimilar metals coming in contact with each other. This is an extremely beneficial attribute in today’s age of light-weighting vehicles where aluminium components are more prevalent.
IS 1573 : Specification for electroplated coatings of zinc on iron and steel
ASTM F2329 / F2329M – 15 : Standard Specification for Zinc Coating to Fasteners