Microstructure of Plasma Sprayed La₂O₃ Modified YSZ Coatings

Yttria stabilized zirconia coatings (YSZ) have received great attention as a good candidate for thermal barrier coatings (TBCs). However, the grain growth and phase transformation, within applied coatings particularly under temperatures higher than 1473 K limit its further applications to great extent. In our present study, in order to develop better understanding of aforementioned phenomena and explore effective methods to conquer this challenge, TBCs using traditional and La₂O₃ modified YSZ powders were deposited by atmospheric plasma spraying and their microstructures were investigated. Results show that the La₂O₃ addition can effectively alleviate the grain growth of coatings under high temperature.