A multilayer strategy for enhancing corrosion performance of Al alloy through closed-packed polymer as a top layer on a defective inorganic layer Early Zahwa Alharissa (a), Wail Al Zoubi (a), Young Gun Ko(a)*
(a) Materials Electrochemistry Group, School of Material Science and Engineering, Yeungnam University, Gyeongsan 38541, Republic of Korea.
Abstract
This present study puts forward of a unique multilayer concept comprised defective-inorganic layer as the first layer and closed-packed organic polymer as the second layer on commercial Al alloy and assessed the electrochemical performance subjected to plasma coating and static conversion respectively. First, the formation of a defective inorganic layer via plasma coating utilized alkaline-silicate based electrolyte in high voltage at ambient temperature by addition of V2O5 particle associated the chemical reaction that consisted of Al-O as main oxide and V-O as the incorporated oxide. Second, the closed-packed organic layer fabricated through static conversion into specific organic solution was triggered by the nucleation of the defective-inorganic layer. The surface structure and phase compositional were investigated for confirming the existence of double-layer sample through scanning electron microscopy (SEM), X-Ray diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), and Fourier Transform Infrared (FTIR). While the corrosion resistance assessment was obtained on the basis of Tafel extrapolation and electrochemical impedance spectroscopy with respect to equivalent circuit model interpretation. Accordingly, the corrosion performance of Al alloy would be enhanced significantly due to the synergistic effect arising from the role of closed-packed polymer and V2O5 as electron donor and acceptor, respectively.
Keywords: Al alloy, multilayer, V2O5, closed-packed polymer, corrosion performance.