A Comparison of Thermal Shock Behavior Between APS and Low-Energy VLPPS ZrO2-7%Y2O3 Thermal Barrier Coatings

ZrO₂-7%Y₂O₃ (YSZ) coatings are commonly used as a thermal protective layer on the metal or alloy component surfaces. In the present study, very low pressure plasma spray using F4-VB and F100 low-energy plasma torches was used to elaborate YSZ thermal barrier coatings (TBCs). Experiments were performed to evaluate the thermal shock resistance of the different TBCs specimens which were heated to 1373 K in a high-temperature cycling furnace and held for 0.5 h, and followed by a static air cooling at room temperature during 0.2 h. For comparison, the APS counterparts were also elaborated to carry out similar experiment. The results indicated that the VLPPS coatings displayed a better thermal shock resistance. Moreover, the failure mechanism of the coatings was discussed, and the microhardness of the coatings after thermal shock test was also measured.