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 aluminium and stainless steels by their oxide layers. The majority of hardware parts are zinc-plated.
