CARACTERIZAÇÃO ELÉTRICA E ESTRUTURAL DA CERÂMICA DE CHUMBO E COBRE
ELECTRICAL AND STRUCTURAL CHARACTERIZATION OF LEAD AND COPPER CERAMICS
Vander Alkmin dos Santos Ribeiro, Adhimar Flávio Oliveira, Rero Marques Rubinger, Claudiney de Sales Pereira Mendonça, Valesca Donizete de Oliveira, Manoel Ribeiro da Silva,
Resumo
As cerâmicas de chumbo e cobre são materiais tecnicamente importantes devido à sua alta permeabilidade magnética, baixas perdas e alta resistividade. Neste manuscrito, apresentamos a produção de um conjunto de amostras através do processo cerâmico, envolvendo reações de estado sólido e alta temperatura entre os óxidos constituintes, e a caracterização da cerâmica Pbx Cu1–x Fe2 O4 , visando a formação de uma estrutura do tipo espinélio com propriedades eletrônicas adequadas para o desenvolvimento de novos dispositivos e aperfeiçoamento dos atuais. Para a caracterização foram realizadas medidas de difração de raios-X, medidas elétricas em corrente alternada e contínua em função da temperatura e Microscopia eletrônica de varredura. A partir da difração de raios-X é determinado que as amostras possuem estrutura do tipo espinélio cúbico e tetragonal e das medidas elétricas que o principal mecanismo de transporte está limitado por uma barreira potencial entre os cristalitos.
Palavras-chave
Abstract
Lead and copper ceramics are technologically important materials due to their high magnetic permeability, low losses and high resistivity. In this paper, we present the production of a set of samples through the ceramic process, involving solid state and high temperature reactions between the constituent oxides, and the characterization of Pbx Cu1–x Fe2 O4 ceramics, aiming the formation of a spinel-like structure with electronic properties suitable for the production of new devices and improvements on the current ones. The characterization measurements considered X-ray diffraction, electrical measurements in alternating current and continuous as a function of temperature and Scanning Electron Microscopy. From the X-ray diffraction it is determined that the samples have cubic and tetragonal spinel type structure and from the electrical measurements that the main transport mechanism is limited by a potential barrier among the crystallites.
Keywords
Referências
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