本研究探討純相氧化物以固態反應法合成堇青石於高溫燒結時的相轉換行為及燒結時相轉換反應對陶瓷體熱膨脹係數所造成的影響。結果顯示原始粉末經過煆燒條件 1300℃/1 h 淬冷後即可得到單一的 α-Cordierite 相，根據 Distortion index 計算分析、 Rietveld method 晶體結構精算、及使用 MAS-NMR 觀察陶瓷體內部的晶體結構，發現無序結構的 α-Cordierite 相隨後續燒結溫度升高及持溫時間增長產生相轉換反應逐漸形成有序結構的 β-Cordierite 相。
根據熱膨脹係數的量測結果顯示熱膨脹係數隨燒結溫度升高及持溫時間增長而上升，此變化趨勢與 β-Cordierite 相含量的增加趨勢相同，因此判斷 β-Cordierite 相含量越多會造成陶瓷體的整體熱膨脹係數上升，若要得到較低熱膨脹係數的陶瓷體則需要在製備過程中注意製程參數條件的調整避免 α-Cordierite 相轉換成 β-Cordierite 相。

關鍵詞：堇青石、相轉換、熱膨脹行為

This study aimed to investigate phase transformation reaction at high temperature and the effect of phase content on the thermal expansion behavior of cordierite ceramics.
Magnesium oxide, aluminium oxide and silicon dioxide were used to synthesize α-Cordierite through solid-state reaction at 1300℃/1 h. According to Distortion index, Rietveld method, and MAS-NMR, the disorder structure (α-Cordierite) has transformed to order structure (β-Cordierite) when sintering temperature and time increased. The phase transformation reaction was found to be processed by rearrangement of the position of atoms in the structure.
It was shown in this study that β-Cordierite phase has increased the thermal expansion coefficient.

Keywords : cordierite, phase transformation, thermal expansion behavior

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