The role of formation of continues thermally grown oxide layer on the nanostructured NiCrAlY bond coat during thermal exposure in air

► Growth of CSN at the Al2O3/YSZ interface of nano TBC system was much lower. ► Formation of dense and continues Al2O3 (TGO) layer on the nanostructured NiCrAlY. ► Formation of discontinues and thicker Al2O3 (TGO) layer on the normal NiCrAlY coating. ► Bi-layered TGO thickness in normal TBC system was higher than that of nano TBC system. ► Continues Al2O3 layer on the nano BC would act as a strong barrier for oxygen infiltration.