الفهرس | Only 14 pages are availabe for public view |
Abstract Inorganic-organic sol-gel coatings were studied as corrosion protection for low carbon steel in 0.5M H₂SO₄ solution. Potentiodynamic Polarization, Electrochemical Impedance Spectroscopy (EIS) and Electrochemical Frequency Modulation (EFM) were utilized to study their corrosion behavior and protection effect. First, Clindamycin and Cefaclor organic compounds were tested as corrosion inhibitors for the carbon steel in the test solution, which give good results. Second, the two organic compounds were incorporated into Tetraethyleorthosilicate (TEOS) solution to get hybrid solgel, and then applied homogeneous thin films on the metal surface via spin coating technique. Corrosion tests revealed that the hybrid sol-gel films exhibit better corrosion protection than those made of pure sol-gel. Metal surfaces were examined after immersion in the 0.5M H₂SO₄ solution for 24 hrs, by scanning electron microscope (SEM) and Atomic Force Microscope (AFM). Results showed that specimens coated with hybrid solgel films appeared clean and corrosion less as compared to those coated with pure sol-gel. In addition, all films were analyzed by X-Ray Diffraction Analysis (XRD) which confirmed the presence of Clindamycin and Cefaclor organic compounds mixed with TEOS on the metal surface within the hybrid sol-gel films, while those of pure sol-gel appeared without any of these compounds. Thickness of the hybrid film was measured and found to be about 1μm, while hardness was found 3H which is considered hard and scratch resistant film. |