Performance of cold spray coatings on Fe-based superalloy in Na2SO4-NaCl environment at 900 °C

NiCrAlY and NiCoCrAlY coatings were deposited on Fe-based Superfer 800H superalloy with cold spray process. The aim of the present work is to compare hot corrosion behavior of NiCrAlY and NiCoCrAlY cold spray coatings on Fe-based superalloy in Na2SO4-10%NaCl environment at 900 °C under cyclic conditions for 50 cycles. The thermogravimetric technique was used to establish the kinetics of corrosion. The corrosion products have been analyzed using the XRD, SEM/EDAX and X-ray mapping techniques. Both coatings protect the underlying Superfer 800H. The NiCoCrAlY coating performed relatively better than NiCrAlY coating against hot corrosion in the given environment.