添加氧化鈦能促進氧化鋁燒結收縮，但會造成晶粒快速成長；添加氧化鎂則能抑制氧化鋁晶粒成長，並能獲得較高之最終密度。因此，本研究以了解氧化鈦 (0.4, 1 wt%) 及氧化鎂 (0.05, 0.2, 0.4 wt%) 共添加對氧化鋁燒結行為以及晶粒成長之影響做探討，並以在較低溫度獲得高緻密且細晶粒之氧化鋁陶瓷體為目的。
研究結果發現，單一添加氧化鈦之樣品，隨著添加氧化鈦量增多，可以較快的速率達到緻密，並可獲得較高之最終密度。而氧化鈦固定為 1 wt% 之共添加樣品，隨著氧化鎂添加含量之增加，與單一添加氧化鈦之樣品比較，抑制晶粒成長之效果亦逐漸顯著，燒結收縮速率也隨之降低，但相對於純氧化鋁而言，仍保有較大的燒結收縮速率以及收縮量，可獲得較高之最終密度。而燒結體晶粒大小則介於單一添加氧化鈦及純氧化鋁燒結體間。

Doping TiO2 into alumina can promote its sintering shrinkage and grain growth; while, another dopant-MgO can inhibit grain growth and enhance the final sintered density. In this study, we investigate the sintering and grain growth behavior of pure alumina codoped with TiO2 (0.4, 1wt%) and MgO (0.05, 0.2, 0.4 wt%) base on their individual specific functions.
The results show that alumina doped only with TiO2 can be densified easily, and when the doping quality was raised from 0.4 to 1 wt%, the densification rate increases simultaneously. When the TiO2 doping quantity was fixed at 1 wt% and codoped with MgO from 0.05 to 0.4 wt% gradually, the effect on grain growth inhibition is obvious compare with TiO2 single doping. In this TiO2 and MgO co-doping system, the grain size of sintered bulk is between TiO2 single doped alumina and pure alumina. Otherwise, the specimens can be sintered easily than pure alumina yet. Hence, we can get fine grain densified alumina specimens easily in lower temperature.

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