| Summary: | 碩士 === 國立清華大學 === 工程與系統科學系 === 95 === In the thesis, we changed the titanium dioxide contents under different heat treatment conditions to observe the variations of the inner microstructure while the phase transform. X-ray powder diffraction, X-ray absorption spectroscopy and infrared spectroscopy were used. According to the XRD results, while the titanium dioxide contents were increased, the phase transformation temperatures of the main phases (β-quartz solid solutions and β-spodumene solid solutions) were decreased. And then various secondary phases were usually precipitated at higher temperatures. XAS showed that the local environment of Ti and Zr were changed by different thermal treatment conditions. According to the XANES of Ti (Zr) K-edge studies, the coordination numbers changed from lower to higher coordination number while the sample transforms from an amorphous glass to a highly crystalline glass ceramics (Ti from 4 to 6, Zr from 6 to 8). But these phenomena would not be observed at the samples of the 4 wt% TiO2. More information about the materials fine structure can be obtained from infrared spectroscopy data. We could utilize the variations of the IR spectral feature to decide that the bond of the inner atoms, the kinds of bonding vibration and the phase type.
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