珠磨對BaTiO3粉體物性、燒結後性質及其介電特性的影響

The Influences of Bead Milling on Physical, Sintering and Dielectric Properties of BaTiO3 Powder

林政德(Cheng-De Lin)

指導教授 ： 王錫福 ； 吳玉娟

國立臺北科技大學/工程學院/材料科學與工程研究所/碩士(2010年)

摘要

近年來，積層陶瓷電容的微型化，主要是以介電層薄層化為主要趨勢[4]，此乃因獲得高電容值之積層陶瓷電容，其最有效的方式為降低積層陶瓷電容中介電層厚度以增加介電層數。本研究主要是希望能瞭解鈦酸鋇粉體經由高能研磨後其相關物理性質的變化，在此實驗中以新式的珠磨機為主要儀器，並以研磨時間為實驗變數在同一批實驗中直接取樣，選用兩種不同的商業鈦酸鋇粉末並加入介電陶瓷添加劑，針對高能研磨後樣品粉之粉體物性、燒結後性質及其介電特性進行試驗比較。
本實驗結果顯示，隨著比能量與珠磨時間增加，鈦酸鋇粉末之粒徑與c/a比會隨之降低且粒度分佈會向偏移並集中；當鈦酸鋇粉末之起始粉末粒徑越小其經過適當溫度燒製後，可發現陶瓷體之平均晶粒尺寸會對其介電性質有顯著之影響。

關鍵字

鈦酸鋇 ； c/a比 ； 高能研磨 ； 研磨時間

並列摘要

Demands are high in recent years for the thin dielectric layer of multi-layer ceramic capacitor (MLCC) for development of miniaturization. To achieve high capacitance values, the thickness of the dielectric layer in MLCC should the decreased are the number of the MLCC intermediate layer need to increased.
In this investigation, influences of the high energy bead milling on physical properties of BaTiO3 powder are studied. The experiment instrument was a new type of bead miller. One of the experimental variables was the milling time, while two different commercial powders used were barium titanate powders (BaTiO3) with dielectric ceramic additive powders. In order to discuss the effects of beads milling time, physical, sintering and dialect properties of milled powders are investigated.
In the present study, bead milling time was selected as a process parameter to affect the powder properties. After milling for different times, the powders were characterized in terms of size distribution and c/a ratio and the microstructure and dielectric property of sintered samples, aiming at understanding the relationship between bead milling condition and the powder characterized.
The results show that barium titanate powder of particle size and the c / a ratio decrease and the powder size distribution is shifted and become narrow when the specific milling energy and time increase. After sintering, the results reveal the dielectric properties changes with the sample microstructure.

並列關鍵字

BaTiO3 ； c/a Ratio ； high Energy mill ； milling time

參考文獻

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