Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5440332 | Journal of the European Ceramic Society | 2017 | 8 Pages |
Abstract
The ferromagnetic glass ceramics in the system SiO2-B2O3-Fe2O3-SrO were prepared via four different fabrication methods, i.e., fiber-drawing, melt-quenching, natural-cooling, and annealing, without performing any nucleation and crystallization heat treatments. The influences of chemical composition and fabrication method on the spontaneous crystallization of magnetite were investigated by X-ray diffraction, scanning and transmission electron microscopy. The X-ray diffraction patterns show the presence of nanometric magnetite crystals in the glass matrix, and the increasing boron oxide can promote the spontaneous crystallization of magnetite. The estimated size of crystallized magnetite varies between 12 and 50Â nm. The magnetic properties of the glass ceramics derived from the four fabrication methods were analyzed using a Vibrating sample magnetometer (VSM), Agilent HP8722ES vector network analyzer and Mössbauer spectra. We find that both the saturation magnetization (MS) and coercivity (Hjc) depend on the chemical composition and fabrication method. The calorimetric measurements were carried out using Orton Standard Dilatometers.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Jianan Liu, Chaofeng Zhu, Meimei Zhang, Yanfei Zhang, Shujiang Liu, Xuena Yang,