Investigated microstructure of Al<inf>2</inf>O<inf>3</inf>/13wt%MgO nanocomposite coating prepared by plasma-sprayed technique

Abstract

© 2016 Trans Tech Publications, Switzerland. The MgO nanowire growth on Al2O3 lamellae has been placed on plasma-sprayed process. The chemical compositions of nanocomposite powders were appeared α-Al2O3 and cubic-MgO phases. After deposited by plasma sprayed coating, the chemical composition has presented major of γ-Al2O3, minor of α-Al2O3 and cubic-MgO phases. The microstructure of Al2O3/13wt%MgO coating was exhibited high density and good distribution of MgO lamellae with thickness in range 241 μm. The MgO nanowire had dispersion that width diameter in range of ∼96.5 nm and average of length 884.9 nm, on the Al2O3 lamellae. The result of nanostructure MgO nanowire generation could be explained that the MgO clusters have been depressed on the Al2O3 lamella at the low temperature zone, then deposited and nucleated in during plasma-sprayed. It was found that the new phase of spinel Al2MgO4 form interaction between Al2O3 and MgO. The average porosity of ∼14% was observed in Al2O3/13wt%MgO nanocomposite coating.