Abstract Al2O3-doped tetragonal yttria-stabilized zirconia (t-YSZ) coatings were prepared by plasma spraying under various spraying parameters. The analysis of variance reveals that only Al2O3 addition significantly affects thermal properties of coatings. The electronic structures and microstructures results show that the increase in number of defects and boundary density with the increasing addition of Al2O3 enhances phonon scattering resulting in a decrease in the thermal conductivity, which suggests that the Al2O3 addition can improve the insulation performance of the YSZ coating. The increase in boundary density with the increase in Al2O3 addition is due to recrystallization resulting from the decreasing melting point of Al2O3–YSZ composites, lattice distortion, and the presence of amorphous structure and monoclinic Al2O3 pinning at grain boundaries. The change in the coefficient of thermal expansion with Al2O3 addition is attributable to the variation in the bonding strength of the Al2O3-doped t-YSZ caused by the change in lattice constants.

中文翻译：

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Al2O3掺杂四方YSZ涂层的微观结构、电子结构和热性能研究

摘要 通过等离子喷涂在不同喷涂参数下制备了Al2O3掺杂的四方氧化钇稳定氧化锆(t-YSZ)涂层。方差分析表明，仅添加 Al2O3 会显着影响涂层的热性能。电子结构和微观结构结果表明，随着Al2O3添加量的增加，缺陷数量和边界密度的增加增强了声子散射，导致热导率降低，这表明Al2O3的添加可以提高YSZ涂层的绝缘性能. 随着 Al2O3 添加量的增加，边界密度的增加是由于 Al2O3-YSZ 复合材料的熔点降低、晶格畸变、以及在晶界处存在无定形结构和单斜 Al2O3 钉扎。热膨胀系数随 Al2O3 添加的变化归因于 Al2O3 掺杂的 t-YSZ 键合强度的变化由晶格常数的变化引起。