Non-stoichiometric crystallization of L2S-B2S glasses

• Grant number: 14/01910-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2014
• End date: March 31, 2015
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Edgar Dutra Zanotto
• Grantee: Rogério Zulzke Pompermayer
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated research grant: 13/07793-6 - CEPIV - Center for Teaching, Research and Innovation in Glass, AP.CEPID

Abstract

The crystallization of non-stoichiometric glasses is very important to the understanding and prevision of the behavior of vitreous materials in general, once in those systems the crystallization of two or more phases take place simultaneously. The glass ceramic materials are seen in a wide range of branches of industry and technology, which makes this present study relevant to a better understanding of applicable processes. In order to provide posterior studies in this area, the present work consists in obtaining and characterizing glasses of the system L2S-B2S (lithium disilicate and barium disilicate) in 10 different compositions, as well as measuring the growth rate of crystals in LS-CS glasses (lithium metasilicate and calcium metasilicate), currently under study in LaMaV (Vitreous Materials Laboratory-UFSCar). Preliminary studies show that it is possible to obtain L2S-B2S glasses and that the LS-CS system shows layered growth and the formation of pores in the compositions on the left side of the equilibrium diagram (from the eutectic equilibrium to the calcium metasilicate). Thus, the theory concerning the formation of pores will be applicable in order to perceive the density difference between the crystalline phases and the residual glass.