Effect of silane on corrosion resistance and aerodynamic performance of 6063 Al alloy inertial air–water separator

Abstract

PurposeThe purpose of this paper is to improve the corrosion resistance of anodized 6063 Al alloy inertial air–water separator by means of silane technology and to investigate the effect of corrosion-generated surface roughness changes on aerodynamic performance.Design/methodology/approachThe BTSE-KH560 double-layer silane film treatment technique is used to close micropores on the anodic oxide film surface. The microstructure of the coating is observed by scanning electron microscopy, the coating structure of the specimens is determined by X-ray diffraction (XPS) and the corrosion resistance is determined by electrochemical and salt-spray tests. Computational fluid dynamics is also used to calculate the effect of roughness and analyse the change in separator performance.FindingsThe silane film deposited on the surface of the anodic oxide film acts as a good seal against microporous defects on the surface of the anodic oxide film and reduces the surface roughness. Electrochemical and salt-spray tests show that the silane film improved the corrosion resistance of the anodized film. The roughness produced by the corrosion deteriorates the performance of the separator.Originality/valueThe porous structure of the anodized coating makes it easier for corrosive ions to enter the substrate and cause pitting corrosion. Therefore, in this study, the corrosion behaviour of the coating in the marine environment and its effect on aerodynamic performance are investigated using a BTSE-KH560 double-layer silane coating with a sealing effect.