Corrosion Inhibition of Al-4.5%cu/15zrsio4 Composite in Hcl by Lacl2

The corrosion characteristics of Al-4.5Cu/ZrSiO4 particulate composite in 0.5molar hydrochloric acid without and with lanthanide chloride salt have been investigated. I5% ZrSiO4 was used for the production of the Al-4.5Cu/ZrSiO4 particulate composite using squeeze cast method. Addition of 15% zircon sand resulted to 5.04% decrease in density and 82.61% increase in hardness with respect to the unreinforced Al-4.5Cu matrix alloy. The time, temperature and concentration of inhibitor were varied in the range of 2-10hr, 30C-75 and 250- 1000ppm respectively. Analysis of variance (ANOVA), factorial design and Arrhenius kinetic approach were used to explain the corrosion mechanism. All statistical design was computed at 95% confidence level. Results show that maximum inhibition was observed at 250ppm. An inhibition efficiency of 73.58% was observed after 10 hours of exposure in 0.5molar hydrochloric acid at 250ppm inhibitor concentration and 30C. The analysis of variance and factorial design were in good agreement with the kinetic analysis.