Investigating the influence of NaCl concentration on the electrochemical corrosion behavior of metal oxide reinforced magnesium matrix composites

This research examines the impact of different NaCl concentrations on the corrosion performance of AZ91D nanocomposites enhanced with nano metal oxides such as Zinc oxide (ZnO), Manganese oxide (MnO), and Titanium oxide (TiO2) through an electrochemical test method. The proposed materials were fabricated using a stir-squeeze casting process paired with an ultrasonication setup. In an argon gas-protected system, T6 heat treatment conditions were applied to these casted composites. The electrochemical corrosion results revealed that the ATO nanocomposite at 2.5% of NaCl concentration achieved lower corrosion current density (I-corr) (1.456 x 10(-7) A/cm(2)) and higher corrosion potential (E-corr) (- 1.08 V) owing to the formation of Mg2TiO3 precipitates, which act as a corrosion protective layer as well as reduce the corrosion rate. Based on the nyquist plot, the alloy and nanocomposites electron transfer rate were varied in the following sequence of AZD < AMO < AZO < ATO. The corroded samples Scanning Electron Microscope (SEM) and 3D profile image show ATO composites have minimum amount of crevice corrosion and peaks formation than other materials. Results from EDAX and elemental mapping confirm the presence of Mg2TiO3 precipitates on the ATO nanocomposite.