Electroless nanoceria films on nickel-based superalloy

Abstract

Ceria films were deposited by electroless method on a nickel-based superalloy, Superni 75, to improve its performance at high temperatures. Ceria was produced from cerium acetate using triethanolamine as the reducing agent. The films were produced at three concentrations -0.1, 0.2 and 0.3 M of cerium acetate, to study the effect of increasing cerium concentration. For comparative study, the coated and bare substrates were oxidized at 1173 K for 100 h in air. The morphology and the chemistry of the oxide scale formed were analysed using FEG-SEM/EDS and XRD. It has been observed that increasing the cerium concentration in the film increases the oxidation resistance of the substrate which is evident from the calculated parabolic rate constant. It was also observed that the morphology of the scale improves with the increase in the concentration of cerium in the film. The scale formed on the ceria-coated substrate at 0.3 M concentration is dense and more uniform.

Influence of processing conditions on the properties of thermal sprayed coating: a review

“…Super alloys are alloys that are generally used in hightemperature application such as steam generators and nuclear industries owing to its high mechanical strength, wear and corrosion resistance [145][146][147]. However, based upon the type of base elements, super alloys can be classified into three categories, which are Ni, Co, and Fe based.…”