A note on the peeling of the zinc layer in galvanised coatings

Abstract

Peeling of the outer zinc layer on galvanised coatings, which occurs when galvanised articles are slowly cooled or used at elevated temperatures, has been found to be associated with the formation of cavities at the zeta–eta interface when galvanised articles are held for relatively short periods of time at temperatures in the region of 400°. It is tentatively suggested that cavities are formed by precipitation of vacancies, which arrive at the interface due to zinc being the predominantly diffusing species in the alloy layer.