Abstract The effect of adding method of Sc2O3 on the densification and microstructure of magnesium aluminate spinel prepared by co-precipitated method was investigated. Sintered products were characterized in terms of densification, phase analysis, quantitative elemental analysis, microstructure and flexural strength. Sintering additives were added in the form of Sc salt and in the form of scandium oxide, respectively. No matter in what way to add, sintering additives exist in the form of Sc2O3. Moreover, incorporating of Sc3+ into the spinel structure increases lattice parameters, which improves the diffusion, mass transfer, and densification. The microstructure of sintered samples with adding Sc salt as a sintering additive is more compact and the grain size distribution is more uniform although their grain size is larger compared with that of sintered samples with adding scandium oxide as a sintering additive. Moreover, the optimum flexural strength (97 MPa) of the sintered products is obtained on sintering at 1650 °C with the addition of Sc salt.

中文翻译：

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添加Sc 2 O 3 方法的铝酸镁尖晶石的致密化和显微组织

摘要 研究了Sc2O3的添加方式对共沉淀法制备的铝酸镁尖晶石致密化和微观结构的影响。烧结产品在致密化、相分析、定量元素分析、微观结构和弯曲强度方面进行了表征。烧结添加剂分别以钪盐和氧化钪的形式加入。无论以何种方式添加，烧结添加剂都以Sc2O3的形式存在。此外，将 Sc3+ 加入尖晶石结构会增加晶格参数，从而改善扩散、传质和致密化。与添加氧化钪作为烧结添加剂的烧结样品相比，添加Sc盐作为烧结添加剂的烧结样品的晶粒尺寸更大，但其微观结构更致密，晶粒尺寸分布更均匀。此外，烧结产品的最佳弯曲强度 (97 MPa) 是在 1650 °C 下通过添加 Sc 盐烧结获得的。