Composite structure of YSZ embedded in NiCoCrAlTaY bond coat induces thin and multilayered Al2O3 film to extend the thermal cycle life of thermal barrier coatings

This study employs cold spraying technology to introduce supersonic-YSZ ceramic particle impacts onto the bond coat, enabling control the coating structure and interface morphology of the bond coat of thermal barrier coatings. The TBCs with YSZ ceramic particle-dispersed NiCoCrAlTaY bond coat were deposited and the dispersed distribution of YSZ ceramics changes the nucleation and growth behavior of oxides of the bond coat during high-temperature oxidation, which inducing the formation of thin and multilayered structure TGO that effectively suppresses the cracking phenomenon caused by concentrated oxide growth at coating interface during thermal cycling test at 1100 °C. The thermal cycling life of the specimens with NiCoCrAlTaY-mixed YSZ composite structure bond coat reached 68 days, which was 2.5 times longer than that of the specimens with APS NiCoCrAlTaY bond coat. Significantly enhancing oxidation resistance and service life of the coating. •An in-situ formed Al2O3 multilayered structural that extended service life of TBCs.•To show the oxidation behavior of the thin and multilayer structural Al2O3 film•To simulate the thermal stress in oxidation by the finite element method•To discuss the formation mechanism of the multilayer structural Al2O3 scale