以正硅酸乙脂试剂、乙醇试剂及蒸馏水为原料，运用溶胶－凝胶工艺制备了无定型ＳｉＯ２。采用ＴＧ－ＤＴＡ、ＸＲＤ及ＳＥＭ等方法研究了ＳｉＯ２加热晶体化过程中的相变行为，首次报道了体型ＳｉＯ２网络的ＳＥＭ照片。对试验结果进行了动力学及热力学讨论。 An amorphous SiO 2 was prepared by sol - gel process using orthosilicic acid ethyl ester reagent, ethanol reagent and distilled water as raw materials. The phase transition behavior during the heating crystallization of SiO2 was investigated by TG-DTA, XRD and SEM. The SEM image of the bulk SiO2 network was first reported. The kinetics and thermodynamics of the test results were discussed.