Crystallization of Gahnite in CMAS Glass Forming System - Mechanism and Process Kinetics
| Periodical | Advances in Science and Technology (Volume 68) |
|---|---|
| Main Theme | 12th INTERNATIONAL CERAMICS CONGRESS PART G |
| Edited by | Pietro VINCENZINI and Michele DONDI |
| Pages | 59-64 |
| DOI | 10.4028/www.scientific.net/AST.68.59 |
| Citation | Daniela Herman et al., 2010, Advances in Science and Technology, 68, 59 |
| Online since | October, 2010 |
| Authors | Daniela Herman, Tomasz Okupski, Wiesław Walkowiak |
| Keywords | Crystallization Process, Gahnite, Glas Ceramics |
| Price | US$ 28,- |
The crystallisation mechanism of glass-ceramic materials from a CMAS group Al0.37B0.34Fe0.01Mg0.02Zn0.29Ca0.05Si0.78O3 was tested under non-isothermal conditions by the DTA method. Glass-ceramic material of two-phase composition with precipitation of crystallites from islet silicates Zn2SiO4 and a crystalline phase from a spinel group, gahnite ZnAl2O4 was obtained in the system under investigation. Activation energy of a crystallization process Ea was determined and a crystal growth morphology parameter n was computed. It was revealed that in the test material from a CMAS group one could obtain the crystalline phase in the form of ghanite as a result of a controlled process of crystallization. The occurrence of a spinel phase caused the obtained glass-ceramic material had higher fracture toughness (KIC) than material from a CMAS group, containing pyroxene crystalline phases typical for this system.
