Studies on corrosion behavior of 6061 Al—15 vol. pct. SiC(p) composite in HCl medium by electrochemical techniques

Abstract

The micro-galvanic corrosion of SiC reinforced 6061 Al alloys deprives its potential application in the acidic conditions or at high temperatures. Therefore, the corrosion behavior of 6061 Al—15 vol. pct. SiC<inf>(p)</inf> composite in HCl medium at different temperatures was studied using electrochemical impedance measurements and potentiodynamic polarization curves. The studies revealed that, on increasing the ionic concentration of the medium and temperature the rate of corrosion also increases. Scanning electron microscopic imaging of polished and immersed sample in the medium showed the smooth and uneven morphology respectively. Activation parameters like energy of activation was calculated from Arrhenius plots. Entropy and enthalpy values were derived from the plots of transition state theory equation. © 2015, Allerton Press, Inc.