The role of K2O on sintering and crystallization of glass powder compacts in the Li2O-K2O-Al2O3-SiO2 system
authors Fernandes, HR; Tulyaganov, DU; Pascual, MJ; Kharton, VV; Yaremchenko, AA; Ferreira, JMF
nationality International
journal JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
author keywords Glass-ceramics; Lithium disilicate; Sintering; Thermo-physical properties
keywords LITHIUM DISILICATE GLASS; FIXED VISCOSITY POINTS; LI2O-SIO2 GLASSES; CERAMICS; CLAY; TEMPERATURE; NUCLEATION; KINETICS; BEHAVIOR; AL2O3
abstract The effects of K2O content on sintering and crystallization of glass powder compacts in the Li2O-K2O-Al2O3-SiO2 system were investigated. Glasses featuring SiO2/Li2O molar ratios of 2.69-3.13, far beyond the lithium disilicate (LD-Li2Si2O5) stoichiometry, were produced by conventional melt-quenching technique. The sintering and crystallization behaviour of glass powders was explored using hot stage microscopy (HSM), scanning electron microscopy (SEM), differential thermal (DTA) and X-ray diffraction (XRD) analyses. Increasing K2O content at the expense of SiO2 was shown to lower the temperature of maximum shrinkage, eventually resulting in early densification of the glass-powder compacts. Lithium metasilicate was the main crystalline phase formed upon heat treating the glass powders with higher amounts of K2O. In contrast, lithium disilicate predominantly crystallized from the compositions with lower K2O contents resulting in strong glass ceramics with high chemical and electrical resistance. The total content of K2O should be kept below 4.63 mol% for obtaining LD-based glass ceramics. (C) 2012 Elsevier Ltd. All rights reserved.
publisher ELSEVIER SCI LTD
issn 0955-2219
year published 2012
volume 32
issue 10
beginning page 2283
ending page 2292
digital object identifier (doi) 10.1016/j.jeurceramsoc.2012.02.003
web of science category Materials Science, Ceramics
subject category Materials Science
unique article identifier WOS:000304782600026
  ciceco authors
  impact metrics
journal analysis (jcr 2017):
journal impact factor 3.794
5 year journal impact factor 3.536
category normalized journal impact factor percentile 98.148
dimensions (citation analysis):
altmetrics (social interaction):



 


Apoio

1suponsers_list_ciceco.jpg