James J, F.Arya, S.B.Yadav, S.Paul, C.P.2026-02-032025Journal of Materials Engineering and Performance, 2025, 34, 3, pp. 2498-250810599495https://doi.org/10.1007/s11665-024-09137-8https://idr.nitk.ac.in/handle/123456789/20455The mechanical and tribological characteristics of a thermal barrier coating are highly critical in gas turbine applications to resist high-temperature oxidation, corrosion, and solid particle erosion. In the present investigation, a composite coating with alumina and samarium strontium aluminate has been developed through a plasma spraying process. The as-coated composite top coat consisted of three phases ?-alumina, ?-alumina, and Sm<inf>2</inf>SrAl<inf>2</inf>O<inf>7</inf>. The as-coated surface is re-engineered with an Nd: YAG fiber laser to improve the mechanical and microstructural properties. The laser-treated samples showed a better erosion resistance than the as-coated samples. Despite the surface treatment, both the as-coated and the laser-treated samples showed a higher ‘average erosion value’ at an impact angle of 90° for the test temperatures of 200 and 800 °C. In addition, the as-coated and the laser-treated samples have a higher erosion rate at 800 than at 200 °C for the selected impact angles, with a mixed mode of material removal presenting both ductile and brittle failure mechanisms. © ASM International 2024.Aluminum oxideBrittle fractureComposite coatingsDuctile fractureErosionFiber lasersHigh temperature applicationsNeodymium lasersPlasma jetsPlasma sprayingSamarium compoundsSodium AluminateStrontium compoundsSurface treatmentThermal barrier coatingsTribologyYttrium aluminum garnetComposite thermal barrier coatingErosion behaviorErosion mechanismsHigh temperature erosionImpact anglesLaser modificationsLaser treatedMechanical characteristicsSamarium strontium aluminateSurface-modificationAlumina