Mössbauer studies of corrosion products developed in Prohesion test over galvanized steel sheets

M. ZAPPONI; T. PÉREZ; C. RAMOS; C. SARAGOVI

HYPERFINE INTERACTIONS

Springer

Año: 2003 vol. 148 p. 145 - 151

0304-3843

Precoated galvanized steel sheets were submitted to Prohesion test (PT) and to outdoor marine exposure test (OT). The corrosion products were different in both cases. Goethite, lepidocrocite, pyrite and magnetite were found in the Prohesion test samples; the presence of akaganeite cannot be discarded. Surprisingly greigite was detected in these samples, suggesting in addition a located microbiological corrosion process. On the other hand, goethite, lepidocrocite, magnetite, akaganeite and silicates were found in outdoor exposure samples. This study allows the conclusion that in the Prohesion G-85 test the corrosion mechanism is different from that in the marine atmosphere for the analyzed samples and could not be used to predict the performance of this type of outdoor exposed materials.