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中文摘要：
用非等温热分析法研究了莫来石单相胶前驱体的结晶动力学,采用 XRD、TEM和27 Al-NMR 分析了前驱体向莫来石转化的微观结构变化。结果表明,前驱体在950℃开始形成莫来石晶体,结晶过程为以Avrami-Erofeev的随机形核和随后生长机制,动力学三因子：活化能Ea=1086.34 kJ/mol,指前因子A=9.33×1042 s-1,机理函数的微分表达式f（α）=n（1-α）[-ln（1-α）],其中n=3.37。结晶动力学为非均匀形核过程,形核速率I 随时间t 而下降；980℃左右主要以形核控制为主,1000℃左右则以核生长控制为主,晶粒的长大为扩散控制长大机制。
英文摘要：
The crystallization kinetics of mullite from single-phase gel were studied using a non-isothermal ther-mal analysis method.The microstructure changes were investigated by X-ray power diffraction （XRD）,trans-mission electron microscopy （TEM）and 27 Al nuclear magnetic resonance （NMR）spectroscopy.The results show mullite crystallization begins from 950 ℃.The crystallization process confroms to random nuclei produc-tion and the following unclei growth model of n-dimension Avrami-Erofeev.The activation energy Ea and the pre-exponential factor A of mullite crystallization are 1 086.34 kJ/mol and 9.33×1042 s-1,respectively.The differential expression of the corresponding mechanism function was f （α）=n（1-α）[-ln（1-α）] n-1 n ,n=3.37.The nucleation rates are non-uniform which decrease with the time t in crystallization process.Nuclea-tion was the dominant controlling step at about 980 ℃.Nucleation-growth becomes more predominant at about 1 000 ℃.The rates of the grain growth are controlled by diffusion.
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