Here we prepared porous silicon oxynitride (Si₂N₂O) ceramics by reaction sintering of SiO₂ and Si₃N₄ using five different rare‐earth oxides (RE₂O₃, RE = Lu, Yb, Y, Sm, and La) as sintering aids. The influences of RE₂O₃ on the formation, densification, microstructure, and mechanical properties of Si₂N₂O ceramics have been investigated in detail. The results have indicated that with the increase in RE ionic radius, the formation temperature of Si₂N₂O decreases, and the densification process could be promoted by RE₂O₃ with larger RE³⁺ ionic radius. In addition, microstructures and mechanical properties are highly dependent on the RE₂O₃ additives. With the increase in RE³⁺ ionic radius, Si₂N₂O changes from platelike crystals to elongated crystals. The samples doped with La₂O₃ and Sm₂O₃ with elongated crystals exhibit higher flexural strength and higher Vickers hardness.

中文翻译：

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稀土氧化物添加剂对多孔Si2N2O陶瓷形成和性能的影响

在这里，我们使用五种不同的稀土氧化物（RE ₂ O ₃，RE = Lu，Yb，Y，Sm和La ）通过SiO ₂和Si ₃ N ₄的反应烧结制备了多孔氮氧化硅（Si ₂ N ₂ O）陶瓷。）作为烧结助剂。研究了RE ₂ O ₃对Si ₂ N ₂ O陶瓷的形成，致密化，微观结构和力学性能的影响。结果表明，随着RE离子半径的增加，Si ₂ N ₂的形成温度O减少，并且具有更大RE ³⁺离子半径的RE ₂ O ₃可以促进致密化过程。另外，微观结构和机械性能高度依赖于RE ₂ O ₃添加剂。随着RE ³⁺离子半径的增加，Si ₂ N ₂ O从板状晶体变为细长晶体。掺有细长晶体的La ₂ O ₃和Sm ₂ O ₃的样品表现出较高的抗弯强度和较高的维氏硬度。