氧化鋁的應用相當廣泛，而毫微米材料又具有許多優良性質，因此毫微米級氧化鋁的製成以及其性質受到格外的重視。氧化鋁在製程中常常需要經過一連串的相轉換，以達其穩定相 -Al2O3 。
　　本實驗之起始原料是由 boehmite 煆燒獲得 64 nm 之 -Al2O3 粉末，之後施以冷均壓 (200 MPa) 以獲得所需之生坯。為了瞭解在燒結的過程中燒結體微結構的變化，吾人便以不同長度的燒結時間，漸進的燒結溫度 (1100 ~ 1600℃) 來進行燒結。並輔佐以 SEM (scanning electron microscopy) 和水銀孔隙儀來觀察孔洞分佈的變化。在前人研究中我們發現粉末在燒結的過程中會有重排的現象，此現象使得小孔洞被排除而形成更大的孔洞。本研究主要著眼於孔洞在燒結的過程中大小、分佈的變化以及在不同的平均孔洞大小和分佈下之燒結行為。
　　研究發現坯體的燒結收縮呈現二段式，第一階段為 1000℃ 至 1300℃ ，此階段密度並無明顯改變，粒子進行重排，小孔隙逐漸消失，孔隙變大。第二階段則出現明顯的燒結現象。

　　Al2O3 is used in a variety of applications, and it offers many superior properties. Because of this, the process and the properties of ultrafine Al2O3 is very important to us. The process of Al2O3 usually undergoes a series of phase transformation reach to stable -Al2O3.

　　The starting material was 64 nm -Al2O3 obtained from the boehmite and they were then cold isostatically pressed at 200 MPa. To study the evolution of microstructure during sintering of the above compact, sintering was carried out at temperatures from 1100℃ to 1600℃ for different length of time. Microstructural observation were performed using a scanning electron microscope (SEM) and mercury penetration porosimetry to determine pore size distribution. Several studies have shown that particles rearranged with gradual diminishing of the smaller pores and the occurrence of larger pores. The research work focused on the change in pore size distribution during sintering. The sintering behavior of compacts with different in the mean pore size and pore size distribution was also considered in each sintering stage.

　　In the research, the shrinkage of a compact showed two stages. The first occurred between 1100℃ and 1300℃ and the density did not change much, and the particles rearranged with gradual diminishing of the smaller pores and the occurrence of larger pores. When the second stage start, obvious sintering came up.

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