The structural changes in the in-situ controlled crystallizing process of Si-AI-Zr-O(SAZ) amorphous bulk were investigated by laser Ram. an (LRa), infrared (IR) and X-ray diffraction (XRD) techniques. The structure of the amorphous network apparently reorganized at about 920 ℃, resulting in the formation of Si-rich and Al, Zr-rich regions. The t-ZrO2 was crystallized from the Zr-rich region at 920～950 ℃ and poorly defined Al-Si spinel was formed from the Al-rich regions. With the increase in temperature, the peak of Al-Si spinel was enhanced and then disappeared in the XRD pattern, and the characteristic IR band groups of mullite centered in the 1 200～1 100, 1 000～700 and 650～400 em-1 could be observed. At 1 100～1 150 ℃,the Raman bands at 179 and 193 cm-1 typical for the m-ZrO2 occurred and cristobalite was detected, and the main crystalline phases were identified as t-ZrO2 and mullite. These results indicated that mullite was formed by reaction between amorphous silica and the Al-Si spinel which was metastable phase. During the heating process, t-ZrO2 was crystallized firstly and a portion was transformed to m-ZrO2 at high temperature, and the left amorphous silica was transformed to cristobalite.%借助Raman,IR和XRD等技术探讨了Si-Al-Zr-O系非晶在原位受控晶化过程中微结构变化.结果表明,Si-Al-Zr-O系非晶在920℃左右出现网络结构重整,形成了富Si区和富Zr和Al区.在920～950℃间,从富Zr区析出初晶相四方氧化锆,并从富Al区形成Al-Si尖晶石相.随着温度进一步升高,Al-Si尖晶石衍射峰先增强随后消失,同时在1 200～1 100,1 000～700和650～400cm-1观察到莫来石的红外特征峰;当温度升高至1 100～1 150℃,出现了单斜氧化锆的拉曼特征峰179和193cm1,同时形成了方石英,四方氧化锆和莫来石成为主晶相.说明在热处理过程中,Al不是以三氧化二铝形式析出而是先形成过渡AL-Si尖晶石相,随后与非晶二氧化硅反应形成莫来石晶相,Zr首先以四方氧化锆析出,高温下有小部分四方氧化锆发生相变转化为单斜相,其中过剩的非晶二氧化硅转化为方石英.
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