Structure and crystallization behavior of glasses in the BaO-B2O3-Al2O3 system

The structure and the devitrification behavior of barium aluminoborate glas ses, examined by Fourier transform infrared spectroscopy, differential ther mal analysis and X-ray diffraction are reported. The glass compositions are expressed by the general formula: (50 - x/2)BaO .(50 - x/2)B2O3. xAl(2)O(3 ) with x = 2, 4 and 8. All the as-quenched glasses were phase separated. Al uminum acting as glass former gives a more polymerized structure increasing the glass stability with respect to the devitrification process. Surface c rystallization was found to be dominant for all glasses, forming beta BaB2O 4 nanocrystals as the main crystalline phase. (C) 1999 Elsevier Science B.V . All rights reserved.