The Phase Evolution at High-Temperature Treatment of the Oxide-Fluoride Ceramic Flux

The products of high temperature treatment of the oxide-fluoride ceramic flux of the composition MgO (30.0 mass. %) – Al 2O3 (25.0 mass. %) – SiO 2 (20.0 mass. %) – CaF 2 (25.0 mass. %), which was obtained using liquid glass as a binder, were examined by means of X-ray powder diffraction (XRPD). The slag obtained by the ceramic flux remelting at 1773 K according to XRPD data contains MgAl 2O4, CaF 2 and Mg 2SiO 4 phases. High temperature X-ray diffraction data (HTXRD), collected at heating regime, show that the initial components exist in the ceramic flux at temperatures (T) � 1473 K. The partial melting of the ceramic flux is accompanied with formation of crystalline MgAl 2O4 phase. Detail examination of the slag samples by means of scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) microanalysis confirms results of the XRPD and HTXRD studies.