Y₂O₃-stabilised ZrO₂ (YSZ) ceramics have been used for various engineering applications since Garvie et al. discovered phase-transformation toughening in 1975. The performance of YSZ ceramics depends on the YSZ microstructure. In the present review, the tetragonal-to-cubic phase transformation and grain growth are first discussed, organised according to existing hypotheses of microstructure-development mechanisms in YSZ during sintering. We demonstrate that the phase transformation and grain growth can be most reasonably understood by a grain boundary segregation-induced phase transformation (GBSIPT) mechanism and that the solute-drag effect of Y³⁺ ions segregating along the grain boundaries, respectively. Next, the Al₂O₃-doping effect is discussed with emphasis on the microstructure-development behaviour in a small amount of Al₂O₃-doped YSZ, which is widely used in engineering applications. We further discuss the effect of GBSIPT on low-temperature degradation resistance and the effect of grain size on superplasticity, focusing on the nanocrystalline YSZ, which was created by applying the Al₂O₃-doping effect.

中文翻译：

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综述：多晶氧化锆烧结过程中的微观组织发展机理

自Garvie等人以来，Y ₂ O ₃稳定的ZrO ₂（YSZ）陶瓷已用于各种工程应用。1975年发现相变增韧。YSZ陶瓷的性能取决于YSZ的微观结构。在本综述中，首先根据YSZ烧结过程中微观结构发展机制的现有假设，对四方相至立方相变和晶粒长大进行了讨论。我们证明，通过晶界偏析诱导的相变（GBSIPT）机制可以最合理地理解相变和晶粒长大，并且Y ³⁺的溶质-拖曳效应离子分别沿晶界偏析。接下来，讨论了Al ₂ O ₃掺杂效应，着重讨论了少量Al ₂ O ₃掺杂YSZ中的微结构发展行为，该行为在工程应用中得到了广泛应用。我们进一步讨论了GBSIPT对低温降解抗性的影响以及晶粒尺寸对超塑性的影响，重点是通过应用Al ₂ O ₃掺杂效应产生的纳米晶体YSZ 。