Crystallization and Sinter-crystallization of Li2O-Al2O3-SiO2 (LAS) Glass System using an Ultrafast High-Temperature Sintering (UHS) approach

• Grant number: 23/18171-8
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: May 01, 2024
• End date: April 30, 2025
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Ana Candida Martins Rodrigues
• Grantee: Isabela Reis Lavagnini
• Supervisor: Vincenzo M. Sglavo
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Institution abroad: Universitá degli Studi di Trento, Italy
• Associated to the scholarship: 22/13532-0 - Crystallization with ultra-fast concurrent sintering of glass-ceramics of the Li2O-Al2O3-SiO2 (LAS) system with targeted antimicrobial properties in just one step, BP.PD

Abstract

Glass-ceramics of the Li2O-Al2O3-SiO2 (LAS) system are used in various applications, from cooking utensils to telescope mirror substrates, due to their very low (or even zero) coefficient of thermal expansion and, therefore, excellent resistance to thermal shock, combined with great chemical and thermal stability, and high translucency. However, the fast (compared to viscous flow) surface crystallization kinetics along with their low thermal conductivity, contributes to hindering the achievement of dense bodies via traditional sintering, where heat flows from the exterior to the interior of the material, of glass powder pellets, due to the concurrent surface crystallization. In this sense, new techniques such as Ultrafast High-temperature Sintering (UHS), that enables high heating and cooling rates, make it interesting to produce glass-ceramics of the LAS system by sintering and crystallizing compacted glass powder or crystallizing monolithic pieces of glass. So far, only one (recent) study evaluated the use of UHS in producing glass-ceramics from compacted glass powders, but for a different glass system. This recent study shows that this field has potential to be explored. In this scenario, the objective of this project is to explore the production, in an ultra-fast and economical manner, of glass-ceramics from the LAS-system, with high relative density and good mechanical properties, by the UHS technique.