Durable GdTaO₄/YSZ double-ceramic-layer thermal barrier coatings against ultrahigh-temperature thermal shock

Space thin-walled components call for thermal barrier coatings (TBCs) that can withstand temperatures up to 1600 °C for extended durations. However, samples coated with pure yttria-stabilized zirconia (YSZ) coatings failed after only 90 s of exposure to this temperature. In this study, we propose durable GdTaO₄/YSZ double-ceramic-layer TBCs to resist ultrahigh-temperature thermal shock. Compared with the pure YSZ coatings, the GdTaO₄/YSZ coatings demonstrated significantly extended service lifetimes under thermal shock at 1600 °C. Cracking induced by thermally grown oxide (TGO) emerged as a primary failure mode for GdTaO₄/YSZ-coated samples at this temperature. These findings enhance confidence in the application of TBCs in space engines operating at temperatures up to 1600 °C.