Abstract
Lithium disilicate (LD) glasses in system (99-X)(1Li2O:2SiO2)-(1K2O)-XZrO2 (X = 0, 1 and 2 mol %) have been synthesized by melt quenching technique and converted into glass-ceramics by three and four-stage heat treatment schedules. The sequence of phase formation in glass-ceramics with ZrO2 addition has been discussed. The activation energy of crystallization increases with the addition of ZrO2. Rietveld refinement and micro structural analysis show an increase in the amorphous content with the addition of ZrO2. 29Si MAS-NMR, Raman and XPS spectroscopy studies for the glasses reveal that the ZrO2 addition to LD based glasses causes network polymerization and changes the role of network modifying Li+ and K+ species into charge compensators. The increased connectivity of [ZrO6]2- units in the glass network restricts the mobility of Q2 [Si2O6]4-, Q3 [Si4O10]4- and Q4 [SiO2] units, which leads to an increase in activation energies of crystallization and hampers the devitrification ability of glasses.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
