Corrosion Resistance of Hard Coat Anodized AA 6061 in Citric–Sulfuric Solutions
Source abstract
Abstract
Aluminum is a material widely used in aeronautical and transport industries due to its excellent mechanical and corrosion resistance properties. Unfortunately, aluminum alloys are susceptible to corrosion, which limits their use in some corrosive environments. The aim of this work is to characterize hard coat film fabricated by anodizing in a citric–sulfuric acid system using electrochemical techniques. The anodization process was carried out using an aluminum alloy AA 6061 anodization bath: a mix of citric and sulfuric acid solutions were used. For the anodizing process, two current densities were used, 1 and 7.2 A·cm−2. Anodized specimens obtained under different conditions were exposed to a 3.5 wt.% NaCl solution, and their electrochemical behavior was studied by electrochemical impedance spectroscopy (EIS) and cyclic potentiodynamic polarization (CPP) according to ASTM G106-15 and ASTM G5-13, respectively. Scanning electron microscopy (SEM) was employed to determinate the morphology and thickness of coatings. The results showed improved corrosion resistance in 6061 aluminum anodized in citric–sulfuric acid electrolyte compared to those anodized in sulfuric acid solution.
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Research context
OpenAlex topics: Anodic Oxide Films and Nanostructures · Corrosion Behavior and Inhibition · Concrete Corrosion and Durability
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Universidad Autonoma de Nuevo Leon, FIME-Centro de Investigación e Innovación en ingeniería Aeronáutica (CIIIA), Av. Universidad s/n, Ciudad Universitaria, 66455 San Nicolás de los Garza, N.L, Mexico
Universidad Veracruzana, Facultad de Ingeniería Civil, 91000 Xalapa, Mexico
Centro de Investigación en Materiales Avanzados (CIMAV), Miguel de Cervantes 120, Complejo Industrial Chihuahua, 31136 Chihuahua, Mexico
Funding
Consejo Nacional de Ciencia y Tecnología
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