Preparation and characterization of Al2O3 coating by MOD method on CLF-1 RAFM steel

摘要

Metal organic decomposition (MOD) method was proposed to prepare Al2O3 TPB coatings on CLF-1 RAFM steel. A comprehensive characterization of SEM, XPS, and XRD demonstrated the formation of Al2O3 coatings. The effect of the preparation parameters, including annealing temperature T-a, withdrawal speed V-W, and immersion time t(i) on the microstructure and properties of the coatings was investigated. It showed that amorphous aluminum oxide coating began to transform to gamma-Al2O3 at temperature of T-a = 600 degrees C. The Al2O3 coating with T-a = 700 degrees C and T-b = 500 degrees C performed the best crystallization feature. The hardness of the coatings gradually increased with increasing V-W, while the corrosion resistance exhibited a reverse trend. Meanwhile, the nanohardness and corrosion resistance of the coating with t(i) = 300 s was improved as compared to the coating with t(i) = 0 s. Moreover, the effect of particle size and substrate oxidation on the mechanical property and corrosion resistance of the coatings was discussed. (C) 2017 Elsevier B.V. All rights reserved.