TY - JFULL AU - Bogdan Il. Bogdanov and Plamen S. Pashev and Yancho H. Hristov and Dimitar P.Georgiev and Irena G. Markovska PY - 2012/5/ TI - Non-Isothermal Kinetics of Crystallization and Phase Transformation of SiO2-Al2O3-P2O5-CaO-CaF Glass T2 - International Journal of Materials and Metallurgical Engineering SP - 335 EP - 338 VL - 6 SN - 1307-6892 UR - https://publications.waset.org/pdf/3774 PU - World Academy of Science, Engineering and Technology NX - Open Science Index 64, 2012 N2 - The crystallization kinetics and phase transformation of SiO2.Al2O3.0,56P2O5.1,8CaO.0,56CaF2 glass have been investigated using differential thermal analysis (DTA), x-ray diffraction (XRD), and scanning electron microscopy (SEM). Glass samples were obtained by melting the glass mixture at 14500С/120 min. in platinum crucibles. The mixture were prepared from chemically pure reagents: SiO2, Al(OH)3, H3PO4, CaCO3 and CaF2. The non-isothermal kinetics of crystallization was studied by applying the DTA measurements carried out at various heating rates. The activation energies of crystallization and viscous flow were measured as 348,4 kJ.mol–1 and 479,7 kJ.mol–1 respectively. Value of Avrami parameter n ≈ 3 correspond to a three dimensional of crystal growth mechanism. The major crystalline phase determined by XRD analysis was fluorapatite (Ca(PO4)3F) and as the minor phases – fluormargarite (CaAl2(Al2SiO2)10F2) and vitlokite (Ca9P6O24). The resulting glass-ceramic has a homogeneous microstructure, composed of prismatic crystals, evenly distributed in glass phase. ER -