Surface engineering for high-temperature applications: stellite 6 coatings for improving the oxidation and hot corrosion resistance of t91 steel

Purpose Ferritic steels are widely used to construct the superheater tubes for boilers present in power plants. Owing to the usage of variety of fuels, these superheated tubes get corroded very easily which account for major losses and unwanted shutdowns. The purpose of this study is to check the corrosion behaviour of Stellite 6 coated steel at high temperature under corrosive environment. Design/methodology/approach In the present investigation, the effect of Detonation gun sprayed Stellite 6 coating deposited on T91 steel was reported under simulated oxidation and hot corrosion environment at 900 °C.SEM and XRD were done to characterize the corrosive product. Findings It was observed that the bare specimen underwent significant spallation, followed by the formation of a porous and massive oxide layer. Although the coating was successfully deposited and improved the corrosion resistance of the steel, major cracks were observed on the surface of the coated specimens. Originality/value Thermal spray coatings are widely used to deposit coatings on the components used in extreme environment. Variety of coating powders are available which can be deposited as per the requirements. However, it is necessary to evaluate the compatibility and durability of the coating with the specific alloy. Therefore, in the present investigation, Detonation gun sprayed Stellite 6 coating deposited on T91 steel was studied under simulated oxidation and hot corrosion environment at 900 °C. Peer review The peer review history for this article is available at: Link to the website of web of science.