Obtenção de nanopartículas de hexaferrita de bário pelo método pechini

In this study barium hexaferrite was (general formulae BaFe12O19) was synthesized by the Pechini method under different conditions of heat treatment. Precursors like barium carbonate and iron nitrate were used. These magnetic ceramic, with magnetoplumbite type structure, are widely used as permanent...

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Detalhes bibliográficos
Autor: Galvão, Sheila Bernhard
Formato: tesis de maestría
Estado:Versión publicada
Fecha de publicación:2010
País:Brasil
Recursos:Universidade Federal do Rio Grande do Norte (UFRN)
Repositorio:Repositório Institucional da UFRN
Idioma:portugués
OAI Identifier:oai:repositorio.ufrn.br:123456789/12693
Acesso em linha:https://repositorio.ufrn.br/jspui/handle/123456789/12693
Access Level:acceso abierto
Palavra-chave:Nanomagnetismo
Hexaferrita
Pechini
Curva de histerese e nanopartículas
Nanomagnetic
Hexaferrite
loop hysteresis and nanoparticles
CNPQ::ENGENHARIAS::ENGENHARIA DE MATERIAIS E METALURGICA
Descrição
Resumo:In this study barium hexaferrite was (general formulae BaFe12O19) was synthesized by the Pechini method under different conditions of heat treatment. Precursors like barium carbonate and iron nitrate were used. These magnetic ceramic, with magnetoplumbite type structure, are widely used as permanent magnet because of its excellent magnetic properties, such as: high Curie temperature, good magnetic anisotropy, high coercivity and corrosion resistance. The samples were characterized by thermal analysis (DTA and TG), X- ray Diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM) end Vibrating sample Magnetometer (VSM). The results confirm the expected phase, which was reinforced according to our analysis. A single phase powder at relatively high temperatures with particle sizes around 100 nm was obtained. The characteristic magnetic behavior one of the phases has been noted (probably superparamagnetic material), while another phase was identified as a ferrimagnetic material. The ferrimagnetic phase showed vortex configuration with two central and slightly inclined plateaus. In general, increase of heat treatment temperature and time, directly influenced the technological properties of the samples