LAUSR

Al2O3–ZrO2–Y2O3 composite coatings were prepared by plasma spraying Al2O3–ZrO2 composite powder with varying amounts of Y2O3. The effects of Y2O3 on the microstructure and properties of the plasma-sprayed Al2O3–ZrO2 composite coatings were investigated, and the results showed that the composition of the composite powder had a significant influence on the microstructure and properties of the Al2O3–ZrO2–Y2O3 coatings. The Al2O3–ZrO2 and Al2O3–ZrO2–Y2O3 coatings were composed of yttria-stabilized zirconia (YSZ), α-Al2O3, and γ-Al2O3. The Al2O3–ZrO2–Y2O3 coating had a lower friction coefficient and wear rate compared with the Al2O3–ZrO2 coating. The Al2O3–ZrO2–Y2O3 coating showed the most uniform and compact microstructure, highest microhardness, good toughness, and adhesive strength when 3 wt.%Y2O3 was added. This method of adding rare-earth Y2O3 to improve the overall performance of Al2O3–ZrO2 coatings has potential application value.