Thermal Shock Resistance of Nano-structured Thermal Barrier Coating Fabricated by Plasma Spraying

The conventional and nano-structured ZrO2-7%Y2O3 thermal barrier coatings(TBCs) were prepared by plasma spraying.The thermal shock resistance at 850 ℃ of the conventional and nano-structured coatings were compared.Meanwhile,the thermal shock failure mechanisms of the coatings were discussed.The results show that whether it is the first time appearance of macro-cracks(local spalling) or achieve thermal shock failure,the thermal shock times of nano-structured coating are significantly higher than the corresponding conventioal coating.The nano-structured coating has better thermal shock resistance than the conventional coating.The failure mechanism of the plasma-sprayed conventional coating is large area of peeling.The failure mode of the nano-structured coating is corner spalling.