Abstract The effects of TiO 2 and CaF 2 on the crystallization kinetics, microstructure, phase evolution and microhardness of Y 2 O 3 -Al 2 O 3 -SiO 2 glass ceramics were investigated by differential scanning calorimetric (DSC), field emission scanning electron microscope (FESEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) techniques. The results show that the addition of TiO 2 is effective to promote crystallization by decreasing the activation energy, refining the grain size and increasing the microhardness. However, the CaF 2 plays an opposite role by increasing the activation energy, coursing the grain size and decreasing the microhardness. Furthermore, the addition of TiO 2 induces bulk crystallization of Y 2 O 3 -Al 2 O 3 -SiO 2 glass. On the contrary, the addition of CaF 2 leads to surface crystallization and decreasing of thickness of surface crystallized layer.

中文翻译：

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TiO 2 和CaF 2 对Y 2 O 3 -Al 2 O 3 -SiO 2 微晶玻璃结晶行为的影响

摘要 采用差示扫描量热法(DSC)、场发射扫描电子显微镜研究了TiO 2 和CaF 2 对Y 2 O 3 -Al 2 O 3 -SiO 2 玻璃陶瓷结晶动力学、微观结构、相演化和显微硬度的影响。 (FESEM)、X 射线衍射 (XRD) 和傅里叶变换红外光谱 (FTIR) 技术。结果表明，TiO 2 的加入通过降低活化能、细化晶粒和提高显微硬度来有效促进结晶。然而，CaF 2 通过增加活化能、改变晶粒尺寸和降低显微硬度而起到相反的作用。此外，TiO 2 的添加诱导Y 2 O 3 -Al 2 O 3 -SiO 2 玻璃的本体结晶。相反，