Abstract:Aiming to explore the oxidation mechanism of thermal barrier coatings with air-film cooling holes, in this research, femtosecond laser was used to prepare the thermal barrier coatings with air-film cooling holes. The microscopic morphology of the air-film cooling holes was observed, and the static oxidation of the perforated thermal barrier coatings was studied at 1000 and 1150 ℃. The growth rate constant of thermally grown oxide (TGO) of the perforated coating is 0.372 μm2·h-1 after the static oxidation at 1000 ℃. The thickness of TGO is increased rapidly and then slowly with the prolongation of the oxidation time. After the static oxidation at 1150 ℃, the growth rate constant of TGO of the perforated coating is 1.26 μm2·h-1, which is slightly larger than that of the unprocessed coating. After oxidation for 100 h, the thickness of TGO at the interface of the ceramic layer and the bonding layer is 11.610 μm, which is close to that of the unprocessed coating. The results show that the growth rate of TGO at the interface of the ceramic layer and the bonding layer is significantly increased and the oxidation process is accelerated with the increase in oxidation temperature. At the same oxidation temperature, the air-film cooling holes accelerate the growth rate of TGO during the short-time oxidation process, which has little effect on the thickness of TGO after oxidation for 100 h.