CORROSION PERFORMANCE OF ZINC-COATED STEELS - MECHANISM, LIFE PREDICTION AND CORROSIVITY MAPPING

摘要

This paper will discuss the corrosion performance and mechanisms of zinc-coated steels for different applications based on the range of corrosion rates and mechanisms in different environments. The issue of performance certainty and life prediction will then be addressed. The methodology for making corrosivity maps using a coating life prediction model will be introduced with an example of the maps developed for Canada. It is hoped that a worldwide map for the corrosivity of galvanized steel can be developed based on such an approach. Remarks will also be made on the development trend and potential for further improvement of the corrosion performance of zinc-coated steels.