Effects of elevated temperature on the corrosion resistance of silver–cobalt oxide–titanium dioxide (Ag/Co3O4/TiO2) nanocomposites coating on AISI 1020

Abstract

The effects of temperature on corrosion resistance of Silver–Cobalt oxide and Titanium Dioxide (Ag/Co3O4/TiO2) nanocomposite coated AISI 1020 in a high-temperature environment was investigated. The Ag, Co3O4 and TiO2 nanoparticles were individually produced by mixing the salt precursors with extract of Piptadeniastrum Africana leaf under the optimized synthesis conditions. The nanocomposite was produced by mixing Ag, Co3O4 and TiO2 nanoparticles (NPs) in equal proportions to constitute 75 wt% of the composite. 10 wt% epoxy resin and its hardener in the ratio (1:1) were added to serve as the binder, while 15 wt% of CNT was introduced to serve as support. The produced Ag/Co3O4/TiO2 nanocomposite was coated on the surface of mild steel (AISI 1020) by the dipping method. The coated samples were heated in a muffle furnace to 35, 100, 200, and 300 °C. Microstructural evolution of the coatings was investigated using X-ray diffraction, scanning electron microscopy and energy dispersive spectrometer. The corrosion resistance of the coated and heated and un-heated steel samples was determined using the potentiodynamic polarization method. The results show that Ag/Co3O4/TiO2 nanocomposite coated sample cured at 100 °C exhibited the highest corrosion resistance of 195.12 Ω.