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Thermal barrier coatings(TBCs)consisting of La2Ce2O7(LCO)and Y2O3-stabilized-ZrO2(YSZ)double-ceramic layer and Dy/Pt co-doped NiAl bond coat were produced by electron beam physical vapor deposition(EB-PVD).Thermal cyclic performance of the TBCs was evaluated by flame shock testing at 1300℃.For com-parison,the TBCs with a undoped NiAl bond coat were also studied.The microstructural evolution and failure mechanisms of the above TBCs during thermal cycling were investigated.Spallation failure of the TBCs with the undoped bond coat occurs after around 500 cycles by cracking at the interface between YSZ ceramic layer and thermally grown oxides(TGO)layer.The TBCs with Pt/Dy modified bond coat reveal improved interface bonding even after 1200 thermal cycles,whereas some delamination cracks are presented in the LCO layer.On the other hand,the Pt/Dy modified bond coat effectively suppresses the formation of the needle-like topologically closed packed phases(TCP)in the single crystal superalloy.