本研究嘗試以膠體成型製程於常壓環境下製備出次微米晶粒之透光氧化鋁燒結體。實驗是以離心分級法收集粒徑分布均一之次微米α-Al2O3粉末，其粒徑分布為80-200 nm，平均粒徑為130 nm。該粉末是以超音波攪拌法使粉末顆粒均勻分散於水中形成漿料，其中未添加有機添加劑。之後再以緩慢的蒸發乾燥過程，最終使粉末顆粒規整堆排成為乾燥之生坯，生坯之相對密度達71.8%。生坯於空氣氣氛中1250°C燒結4小時即成為具有透光性質的之燒結體，其晶粒平均尺寸為531 nm，在可見光波長範圍之總穿透率為79%。

This study performed with colloidally processed narrow-size-distributed sub-micron alumina powders to prepare translucent alumina by pressureless sintering. Narrow-size-distributed powder with an average particle size of 0.13 μm was collected by centrifugal classification. The powders were dispersed by stirring with ultrasonification in a water-based suspension without organic additive. Homogeneous green bodies with relative density of 71.8% were prepared by drying at slow evaporation rates. Samples sintered at 1250°C in air showed a total forward transmittance of 79% in visible wavelength and an average grain size of 0.53 μm.

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