A LITERATURE SURVEY ON THE DEVELOPMENT OF AN ACCELERATED LABORATORY TEST METHOD FOR ATMOSPHERIC CORROSION OF PRECOATED STEEL PRODUCTS

This paper summarizes a literature survey devoted to atmospheric corrosion of steel, coated steel (zinc, zinc-aluminum alloys, aluminum alloys, cadmium) and painted products to set the basis for the development of a new accelerated laboratory test for atmospheric corrosion of precoated steel products. Although a large amount of relevant data were recorded, it appears that no accelerated test has so far reproduced the results in natural environment conditions with a sufficient accuracy and an acceptable reproducibility. This situation results principally from the lack of data on the role of different corroding factors, the lack of appraisal criteria and the lack of information regarding corrosion mechanisms. The development of a new accelerated test to simulate the natural corrosion of painted coated steels occurring on buildings, should be based on data recorded on typical exposure sites (on buildings, under gutters, with various climates) at the same time as test specimens are corroding. The classification for the test variables should be based on an understanding of the corrosion process together with reasonable engineering principles.