Investigation of erosion-corrosion resistance of 2017A aluminium oxidized by micro-arc oxidation process

Abstract

2017A aluminium sample was cut into certain pieces and surface modification was practiced via micro arc oxidation (MAO) method. Aluminum alloy, on the surface of which a ceramic layer was formed, was exposed to an erosive-corrosive environment at room ternparature for different times. During the exposure Al2O3 powder particles were stirred in HCl solution. Mass measurements and XRD phase analyses of the samples were taken before and after the micro arc oxidation process and erosion-corrosion experiment In addition, surface images of the samples were taken by optical microscopy in order to examine the changes in the surfaces of the samples produced by erosive-corrosive environment As a result of this study, it was also determined that an obvious increase in erosion-corrosion resistance of 2017A aluminum oxidized by micro arc oxidation process occured. In particular, by extending the MAO processing time from 5 min to 45 min, an increase of about 6 times in coating thickness was obtained. As a result; in the 3 h erosion-corrosion test the mass loss was reduced from 40.2% to 0.7% and so the erosion-corrosion resistance was increased about 60 times.