Corrosion Study of Aluminum 7075 Alloy in Cationic Aqueous Medium by Surface Analysis

Abstract

The results of the corrosion nature of aluminum 7075 alloy in a cation-containing aqueous medium are reported by using gravimetric tests and surface analysis. The investigation showed a substantial increase in the mass of the specimens after the immersion experiments, while a minor mass change was seen in the Zn²⁺ containing solution. Energy dispersive spectroscopic mapping and cross-sectional pictures showed that the specimen submerged in the Zn²⁺ containing solution developed a zinc-linked layer. The results of X-ray photoelectron spectroscopy showed that aluminum hydroxide was deposited on the surface, and a tiny amount was deposited on the specimen that was sunk in the solution containing Zn²⁺. The present study suggests that the zinc-related layer prevents the alloy from corroding.