Crystallization of 1Na2O.2CaO.3SiO2 glass with Li2O additions: determination of nucleation rates

• Grant number: 05/00948-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2005
• End date: December 31, 2005
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Ana Candida Martins Rodrigues
• Grantee: Bruno Henrique Teider
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

Glasses of the 1Na2O.2CaO.3SiO2 system are known for their homogeneous nucleation. The crystals in this system are solid solutions whose chemical composition varies during crystallization, which, in turn, also leads to variations in the chemical composition of the vitreous matrix. Small quantities of lithium oxide are known to increase the nucleation rate in this system. We therefore propose to measure the nucleation rates of 1Na2O.2CaO.3SiO2 glasses with additions of up to 4 weight % of Li2O, to confirm the increase in the nucleation rate and to investigate possible causes of this behavior. We will also attempt to identify the variables of the Classic Nucleation Theory that are affected by these Li2O additions and that cause the nucleation rate to increase.