Fluoride Ions Effect on the Corrosion Behavior of Pure Aluminum in Deaerated 0.05 M Sulfuric Acid Solutions

Abstract The corrosion study of aluminum‐based materials is the topic of a great scientific attention because of increasing the applications in many sectors of these materials. The fluoride ions (F − ) effect on the corrosion behavior of pure aluminum in deaerated 0.05 M sulfuric acid (H 2 SO 4 ) solutions at 25 °C was investigated. The electrochemical measurements such as open circuit potential and potentiodynamic polarization were accomplished to study the effect of fluoride and sulfate ions present in the test solutions. The optical microscopic and atomic force microscopic images were taken to view the morphologies and surface roughness of pure aluminum which coincidence with the corrosion rates found from the immersion of the test specimens using weight loss method. The surface morphology and elemental compositions of pure aluminum was evaluated by scanning electron microscope and energy dispersive X‐ray spectroscopy, respectively. The results showed that the general corrosion was formed on the surface of pure aluminum. It is also revealed that the surface roughness and amount of corrosion of pure aluminum were increased by the presence of even a very small amount of fluoride ions in deaerated sulfuric acid solutions.