ATOMIC-FORCE MICROSCOPY OBSERVATIONS OF PITTING CORROSION AND INHIBITION ON 7075-T651 ALUMINUM-ALLOY IN HYDROCHLORIC-ACID SOLUTIONS

Atomic force microscopy, a unique surface imaging technique that enabl es the effects of an imposed environment on the substrate to be measur ed and assessed, was used to define the effects of a dilute aqueous hy drochloric acid solution (0.03 N) on a polished and etched surface of a peak aged aluminum-zinc-magnesium alloy (7075-T651). A multifunction al corrosion inhibitor with dichromate, nitrite, berate, and molybdate ions, especially solubilized in an organic medium, was introduced to the study and its corrosion retardation effects were observed in situ by the atomic force microscope.