Microwave absorption properties of Co, Cu, Zn: substituted hexaferrite polychloroprene nanocomposites

AUTOR(ES)

Caffarena, Valeska da Rocha, Capitaneo, Jefferson Leixas, Ogasawara, Tsuneharu, Pinho, Magali Silveira

FONTE

Materials Research

DATA DE PUBLICAÇÃO

2008-09

RESUMO

The magnetic behavior and its relationship with microwave absorbing properties have been investigated for doped Z-type barium hexaferrites (Ba3Co1.3Zn0.3Cu0.4Fe 24O41)/ polychloroprene (CR) nanocomposites. Simultaneous substitutions by Co2+, Cu2+, and Zn2+ ions make possible the use of these materials as RAMs, due to the frequency dependence of µr* (permeability), responsible for the location of the hexaferrite natural resonance. The Cu2+ ions distort the crystalline field due to their electronic configuration, and this behavior results in an increase in the saturation magnetization (Ms), which improve the magnetic permeability. Similarly, the superparamagnetic contribution (associated to the nanometric size) led to the improvement of the microwave absorption.

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