Morphology Analysis and Corrosion Performance on Aluminum Zirconium Composite

The high strength aluminum alloy 5083 of composition 0.4Si 0.4Fe 0.1Cu 0.4Mn 4Mg 0.25 Zn 0.15Ti 0.05Cr and Al balance which has high yield strength of around 200 MPa and tensile strength of 300 MPa and good corrosion resistance for sea water and saline environments, is alloyed with zirconium (Zr), which is highly resistant to heat and corrosion, very strong, malleable and ductile, at various compositions. The alloying element zirconium metal powder is mixed at different proportions of 0.3 wt%, 0.5 wt% and 0.7 wt% with aluminum 5083 as the base metal. Corrosion resistance and morphological properties of the samples were investigated by potentiostatic polarization, scanning electron microscope (SEM) and x-ray diffraction (XRD) tests. The corrosion study has been carried out in 3.5 % NaCl solution at a sweep rate of 1mV/s. After open circuit potential has become stable, the pitting corrosion behavior has been studied after 6 hours of immersion, at a temperature of 350C and a pH value of 7. The results show that the addition of zirconium has increased the corrosion resistance of the aluminum alloy, 0.7 wt% of zirconium sample has given the best results and great resistance against corrosion, allowing them to be applicable for direct application for saline environment.