Effect of the cerium (III) chloride heptahydrate on the corrosion inhibition of aluminum alloy

Abstract

In the present work, the corrosion protection of aluminum alloy AA2024‐T3 has been studied in NaCl solution, with and without the addition of cerium (III) chloride heptahydrate. The corrosion inhibitor efficiency after immersion into 10 mM NaCl, with or without 3 mM of CeCl3·7H2O at 20°C, 40°C, and 60°C was investigated. The performed quantitative tests include electrochemical techniques, such as the method of quasipotentiostatic polarization (Tafel extrapolation), cyclic polarization, and electrochemical impedance spectroscopy to determine corrosion rate (vcorr), inhibition efficiency (η %), protective ability (γ), degree of coverage (ϑ), and pitting nucleation resistance. The samples were analyzed with scanning electron microscopy and energy dispersive X‐ray analysis to evaluate and characterize the precipitates formed on the surface of aluminum samples and to determine dominant type of corrosion. The formation of Ce3+ precipitates occurred on cathodic intermetallic sites and the surface, in general, resulting in improved corrosion resistance. Tested cerium (III) chloride heptahydrate proved to be an effective inorganic corrosion inhibitor for AA2024‐T3 in chloride solution, which, by the action of cerium ions, reduced corrosion on the surface of the studied aluminum alloy.

Cerium Stearate Electrodeposited Superhydrophobic Coatings for Active Corrosion Protection of Anodized AA2024-T3

“…Generally, the copperaluminum alloys, 2xxx series undergoes pitting corrosion in a chloride-containing electrolyte, which is heavily influenced by the presence of intermetallic inclusions of the S phase (Al 2 CuMg). [1][2][76][77][78][79][80] Localized corrosion cells will be easily formed while immersed in NaCl solution due to the different corrosion potential of the aluminum matrix to that of the intermetallic phases. The intermetallic inclusions roughly occupy 3% of the total alloy surface, and when exposed to the neutral chloride-containing electrolyte, Al and Mg from these inclusions selectively dissolves either chemically or electrochemically and creates Cu-enriched microcathodes.…”

“…A luminum (Al) alloys are widely used in aerospace industries as lightweight alloys due to their excellent mechanical properties resulting from their heterogeneous microstructure, the suitability for surface modifications, good electrical and thermal conductivity, ease of recycling, and low density. [1][2][3] However, they are short of good corrosion resistance and susceptible to localized corrosion when exposed to chloridecontaining environments. Chromate-based conversion coatings or organic coatings containing chromium-based pigments are an effective strategy to achieve active corrosion protection to metallic substrates for various applications.…”

A Comparative Study of Green Inhibitors for Galvanized Steel in Aqueous Solutions

“…where I corr is the corrosion current density, EW is the equivalent weight of metal, ρ is the density of zinc, A is the sample area and K is the constant that defines the units of the corrosion rate in millimetres per year [15]. Inhibition efficiency (η) was calculated using Equation (4):…”

Cerium sulfate preparation from Egyptian monazite's rare earth cake for its application as corrosion inhibitor of aluminum alloy AA6061

“…The electrochemical behavior of AA6061 in 3.5% NaCl in the absence and presence of some rare earth elements (REEs) has been studied by means of polarization curves and impedance measurements. The current-potential curves show that, the corrosion resistance of the alloy is greatly enhanced by addition of lanthanide salts especially cerium (Ce) ions which are effective environmentally friendly inhibitors to prevent pitting corrosion [5][6][7][8]. The former forms a passive layer on the alloy surface, whose protective properties are reinforced by ageing in solution [9][10].…”