PS–PVD Alumina Overlayer on Thermal Barrier Coatings Against CMAS Attack

Glassy deposits mainly comprising of calcium–magnesium–alumina–silicate (CMAS) accelerate the spallation thermal barrier coatings (TBCs). In this work, an Al2O3 layer was produced on yttria-stabilized zirconia (YSZ) coating by plasma spray–physical vapor deposition (PS–PVD). The effects processing parameters during PS–PVD process microstructures deposited were investigated. A homogeneous with porosity less than 1% at spray distance 1400 mm, which is much denser atmospheric (APS) and other sprayed 1000 1900 mm. CMAS corrosion test 1250 °C showed that APS dissolved in after 24 h exposure, whereas a dense reaction composed anorthite formed top region effectively protected underlying from infiltration. Thermal cycling behavior Al2O3/YSZ TBC 1050 compared. Bulk occurred within 300 cycling, while little observed even 500 indicating superior durability coating.