Degradation behaviour of sputtered Co-Al coatings on superalloy

► The cyclic high temperature oxidation behaviour of nanostructured Co-Al coatings has been investigated in the present work. ► The oxidation kinetics of Co-Al coatings is very slow due to protective oxide scale formation. ► The corroded products of Co-Al coatings indicated the formation of protective oxide scale such as Cr2O3, Al2O3, CoAl2O4. ► The nanostructured coatings exhibit improved their oxidation resistance as well as the scale-metal adherence.