Madhu Sudana Reddy, G.Prasad, C.D.Shetty, G.Ramesh, M.R.Rao, T.N.Patil, P.2026-02-052021Metallography, Microstructure, and Analysis, 2021, 10, 5, pp. 642-65121929262https://doi.org/10.1007/s13632-021-00784-0https://idr.nitk.ac.in/handle/123456789/23039The plasma spray process was used to form 70%NiCrAlY + 30%TiO<inf>2</inf> and 70%NiCrAlY + 25%Cr<inf>2</inf>O<inf>3</inf> + 5%YSZ cermet coatings on MDN-420 special steel alloy. Cyclic oxidation testing was conducted on coated and uncoated specimens at 700°C under a static air environment. Thermogravimetric analysis was applied to establish the oxidation kinetics. X-ray diffraction (XRD), scanning electron microscopy (SEM)/energy-dispersive x-ray spectroscopy (EDS), and electron probe microanalysis (EPMA) techniques were used to analyze the oxidized products. The NiCrAlY + Cr<inf>2</inf>O<inf>3</inf> + YSZ coating was found to be most resistive when compared with the NiCrAlY + TiO<inf>2</inf> coating in the aggressive oxidation environment. Net weight loss was observed for bare MDN-420 alloy due to sputtering. The oxidation resistance of the coatings was due to formation of Cr<inf>2</inf>O<inf>3</inf>, NiCr<inf>2</inf>O<inf>4</inf>, NiO, and Al<inf>2</inf>O<inf>3</inf> phases. © 2021, ASM International.AluminaAluminum oxideCermetsChromium alloysComposite coatingsElectron probe microanalysisNickel oxideOxidation resistancePlasma jetsPlasma sprayingScanning electron microscopySprayed coatingsThermogravimetric analysisThermooxidationTitanium dioxideYttria stabilized zirconiaCermet coatingsCermet composite coatingCyclic oxidation testingNiCrAlY/cr2O3/YSZNiCrAlY/TiO2Plasma spray processSpecial steelSpecial steel alloyStatic airThermal spray coatingsAlloy steel