Effect of Superficially Applied MnO2 and Al2O3 Oxide Inhibitors in Enhancing High-Temperature Corrosion of T22 Boiler Steel

Hot corrosion is a severe form of industrial corrosion which occurs at high temperatures under the influence of oxidizing gases and can be prominently linked to the formation of a molten salt/ash layer over any metallic substrate. Throughout the years, several types of inhibitors and coatings have successfully been employed to reduce its devastating effects to a certain extent. In this study, two synthesized metal oxides namely Al2O3 and MnO2 were used as corrosion inhibitors and XRD, FTIR analysis were carried out to assess their structural properties. Further, TGA analysis for Al2O3 and MnO2 was carried out to determine thermal stability characteristics. The as-synthesized materials were further deposited as inhibitor coatings (Al2O3 with MnO2 bond coating, MnO2 coating and Al2O3 + 50