Atmospheric corrosion evaluation of electrogalvanized, hot-dip galvanized and galvannealed interstitial free steels using accelerated field and cyclic tests

Three years of outdoor corrosion tests, accelerated with a saline solution spray, and SAE J2334 and GM 9540P accelerated corrosion tests of industrially coated electrogalvanized (GE), hot-dip galvanized (GI), galvanneal (GA) interstitial free steels were performed. The samples were industrially phosphatized and painted with a modified epoxy resin, polyester resin as a primer and a base coat, and a high solid acrylic resin varnish as a clear coat. The effect of the deposition process and zinc mass on atmospheric corrosion of galvanized interstitial free low-alloyed carbon steels was analyzed. The SAE J2334 test was more effective than the GM 9540P test in differentiating the lowest corrosion resistance of the hot dip galvanized steel among the galvanized steels studied. The duration of the accelerated field test played an important role in the steel performance rating. The parameter of maximum corrosion penetration was more efficient to distinguish the effect of the zinc mass on corrosion resistance of the galvanized steel samples evaluated using accelerated field tests.