An Eight-Year Atmospheric and On-Vehicle Corrosion Test of Painted and Zinc Coated Steels

Eleven coated steels and cold rolled steel were painted with three automotive paint systems and subjected to a variety of corrosion test environments. The results of highly accelerated tests correlated poorly with the results of atmospheric and on-vehicle tests. The results of one accelerated atmospheric exposure (“Volvo” test) agreed with those of the longer-term tests. In a comparison of materials, it was found that all zinc-coated steels performed better than cold rolled steel, and that heavier zinc coatings provided longer-term protection than lighter zinc coatings.