The purpose of the present work was to investigate the effect doping with lanthanum aluminate on the phase assemblage and thermal behavior of zirconia ceramics for biomedical applications. Four compositions were prepared by a surface modification route of either conventional tetragonal zirconia (3Y‐TZP) or high translucency cubic‐based zirconia (5Y‐PSZ) to reach a nominal composition of either 0.5 wt. % (3Y‐0.5LAO and 5Y‐0.5LAO) or 5 wt. % of lanthanum monoaluminate (3Y‐5LAO and 5Y‐5LAO). Undoped powders were used as controls. DTA and XRD analyses revealed that lanthanum dizirconate crystallized in the 934°C–936°C range, while lanthanum aluminate crystallized in the 1,056°C–1,063°C range in both types of zirconias doped at the 5% level. No second phase was found in compositions doped at the 0.5% level. The a lattice parameter and the amount of the cubic phase increased in both 3Y‐5LAO and 5Y‐5LAO. The microstructure of the compositions doped with 5% LAO was characterized by well distributed LAO twinned crystals and sparse needle‐shaped lanthanum hexaaluminate crystals. A bimodal grain size distribution was observed in 5Y‐doped compositions. This was attributed to abnormal grain growth of the cubic phase, and in line with aluminum segregation at grain boundaries and the presence of second‐phase LAO crystals.

中文翻译：

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表面改性制备的氧化锆-铝酸镧陶瓷的晶相演化和热行为[J].

本工作的目的是研究铝酸镧掺杂对用于生物医学应用的氧化锆陶瓷的相组合和热行为的影响。通过常规四方氧化锆 (3Y-TZP) 或高半透明立方氧化锆 (5Y-PSZ) 的表面改性路线制备了四种组合物，以达到 0.5 wt. % (3Y-0.5LAO 和 5Y-0.5LAO) 或 5 wt. 单铝酸镧（3Y-5LAO 和 5Y-5LAO）的百分比。未掺杂的粉末用作对照。DTA 和 XRD 分析表明，在 5% 浓度掺杂的两种类型的氧化锆中，重锆酸镧在 934°C–936°C 范围内结晶，而铝酸镧在 1,056°C–1,063°C 范围内结晶。在以 0.5% 水平掺杂的组合物中未发现第二相。一个_3Y-5LAO 和 5Y-5LAO 的晶格参数和立方相数量均增加。掺杂 5% LAO 的组合物的微观结构以分布良好的 LAO 孪晶和稀疏的针状六铝酸镧晶体为特征。在 5Y 掺杂的组合物中观察到双峰粒度分布。这归因于立方相的异常晶粒生长，并且与晶界处的铝偏析和第二相 LAO 晶体的存在一致。