resumo
The present study deals with the design, synthesis and characterization of magnetic glass-ceramics along diopside (CaMgSi(2)O(6))-aegirine (NaFeSi(2)O(6)) join targeted towards their final application as thermoseeds in hyperthermia. The glass-ceramics were prepared from the sintering and crystallization of glass powders obtained through melt-quenching technique. The sintering behavior of glass powders was studied by hot-stage microscopy (HSM) while differential thermal analysis (DTA) was used to study the non-isothermal crystallization kinetics of the as prepared glasses. In order to analyze the crystallization behavior of glasses, the glass powder compacts were sintered at 900 degrees C for 1 h under non-isothermal conditions. The qualitative as well as quantitative crystalline phase analysis of glass-ceramics has been made by X-ray diffraction (XRD)-adjoined with Rietveld-RIR technique. Augite crystallized as the primary phase in all the compositions. The scanning electron microscopy (SEM) was used to shed light on the microstructure of the glass-ceramics while the magnetic properties of glass-ceramics were studied by vibration sample magnetometer (VSM). All the investigated glass-ceramics exhibited ferromagnetic behavior the intensity of which increased with increase in Fe content in the samples. The dependence of magnetic properties on the composition of glass-ceramics has been explained. (C) 2011 Elsevier B.V. All rights reserved.
palavras-chave
THERMOMAGNETIC PROPERTIES; DIOPSIDE GLASS; PHASE-CHANGE; CRYSTALLIZATION; SYSTEM; HYPERTHERMIA; PHOSPHATE; ELEMENTS; WASTES; B2O3
categoria
Chemistry; Physics
autores
Goel, A; Shaaban, ER; Oliveira, JB; Sa, MA; Pascual, MJ; Ferreira, JMF
nossos autores
José Maria da Fonte Ferreira
Professor(a) Jubilado(a)agradecimentos
This work was partially supported by a research project funded by FCT-Portugal (PTDC/CTM/099489/2008-GELMEMS). Ashutosh Goel is thankful to FCT-Portugal for research grant (SFRH/BPD/65901/2009). Also, J. B. Oliveira and M. A. S are grateful to Professor J. M. Machado da Silva for the helpful discussions related with the results of magnetic characterization.