Dependence of glass transition on the structure in Bi-B-Zn oxide glass

In this work, the properties and structures of a series Bi-B-Zn oxide glass with a high Bi2O3 content from 30 to 60 mol% were studied. It was found that when molar ratio of Bi to B exceeded 4:1, crystal phase formed in the glass after quenching. The densities were observed to increase with increase of the Bi2O3 content. When molar ratio of Bi to B is between 40% and 51%, the glasses had a higher rate of densities growth increase. The glass transition temperature (T-g) and crystallization temperature (T-x) values decrease with increase of the Bi2O3 content. The infrared spectra and the Raman spectra both presented [BiO6] increased with increase of Bi2O3 content. The network structure transformation from [BO3] to [BO4] was observed when molar ratio of Bi to B was below 4:1. With further increase of the Bi2O3 content, a structure transformation from [BiO3] to [BiO6] unit was observed. The changes in the structure resulted in the decrease of glass characteristic temperatures. A theory based on the random network theory was proposed to explain the transition of the structure and the property of the glasses. (C) 2018 Elsevier B.V. All rights reserved.