Abstract
Glass-ceramics were prepared from wastes generated from refining of silica sand and kaolin clay, called Kira. Several kinds of Kira were melted at 1300-1550 °C with additions of CaCO3 and quenched in air or water to obtain glasses. The quenched glasses were ground to <48 mesh and used to prepare glass-ceramics. Crystallization of the parent glass occurred above 950 °C, producing wollastonite as a major crystalline phase which gradually transformed to pseudowollastonite above 1150 °C. The macroscopic appearance of the samples changed from transparent pale green glass to smooth-textured shiny white upon crystallization. The thermal expansion coefficient of the glass-ceramics was 5.2×10-6/°C (30-380 °C). The four-point bending strengths of the as-fired glass-ceramics ranged from 76 to 86 MPa. Vickers microhardness was found to be 6.6-7.5 GPa. Since the chemical durability for acid and alkali was excellent in these glass-ceramics, they are considered to be candidates for applications such as building materials, ceramic tiles, etc.
Original language | English |
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Pages (from-to) | 2367-2372 |
Number of pages | 6 |
Journal | Journal of the European Ceramic Society |
Volume | 24 |
Issue number | 8 |
DOIs | |
Publication status | Published - Jul 2004 |
Externally published | Yes |
Keywords
- Glass-ceramics
- Kaolin clay waste
- Mechanical properties
- Silica sand waste
- Waste materials
ASJC Scopus subject areas
- Ceramics and Composites
- Materials Chemistry