title: Trace phase formation, crystallization kinetics and crystallographic evolution of a lithium disilicate glass probed by synchrotron XRD technique.
abstract: X-ray diffraction technique using a laboratory radiation has generally shown limitation in detectability. In this work, we investigated the in situ high-temperature crystallization of a lithium disilicate glass-ceramic in the SiO2-Li2O-CaO-P2O5-ZrO2 system with the aid of synchrotron radiation. The formation of lithium metasilicate and other intermediate phases in trace amount was successfully observed by synchrotron X-ray diffraction (SXRD). The crystallization mechanism in this glass was thus intrinsically revised to be the co-nucleation of lithium metasilicate and disilicate, instead of the nucleation of lithium disilicate only. The phase content, crystallite size and crystallographic evolutions of Li2Si2O5 in the glass-ceramic as a function of annealing temperature were studied by performing Rietveld refinements. It is found that the growth of Li2Si2O5 is constrained by Li2SiO3 phase at 580-700°C. The relationship between the crystallographic evolution and phase transition was discussed, suggesting a common phenomenon of structural response of Li2Si2O5 along its c axis to other silicon-related phases during glass crystallization.
authors.affiliation: 1] Department of Chemical &Materials Engineering, the University of Auckland, PB 92019, Auckland 1142, New Zealand [2] School of Materials Science and Technology, China University of Geosciences (Beijing), Beijing 100083, P. R. China.
authors.forename: Saifang
authors.initials: S
authors.lastname: Huang
authors.affiliation: School of Materials Science and Technology, China University of Geosciences (Beijing), Beijing 100083, P. R. China.
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Department of Chemical &Materials Engineering, the University of Auckland, PB 92019, Auckland 1142, New Zealand.
authors.forename: Wei
authors.initials: W
authors.lastname: Gao
authors.affiliation: Department of Chemical &Materials Engineering, the University of Auckland, PB 92019, Auckland 1142, New Zealand.
authors.forename: Peng
authors.initials: P
authors.lastname: Cao