Effects of V and Mn Colorants on the Crystallization Behavior and Optical Properties of Ce-Doped Li-Disilicate Glass-ceramics

The critical cooling rate and fluorescence properties of lithium (Li) disilicate glasses and glass-ceramics, doped with 2.0 wt% CeO2 and with up to 0.7 wt% V2O5 and 0.3 wt% MnO2 added as colorants, were investigated. the critical cooling rates, Rc, of glass melts were determined using differential thermal analysis and were found to be dependent on the relative concentrations of V2O5 and MnO2, decreasing from 25±3° to 16±3°C/min. Annealed glasses were heat treated first to 670°C, and then to 850°C to form Li metasilicate and Li disilicate glass-ceramics, respectively. the fluorescence intensities of the Ce-doped glasses and glass-ceramics decrease by a factor of 100 with the addition of the transition metal oxides. This optical quenching effect is explained by the association of the Ce3+ ions with the transition metal ions in the residual glassy phase of the glass-ceramics