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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

The effects of the pressing step on the microstructure and aging of NdFeB bonded magnets

Texto completo
Autor(es):
Perigo, E. A. [1] ; de Campos, M. F. [2] ; Faria, R. N. [3] ; Landgraf, F. J. G. [1, 4]
Número total de Autores: 4
Afiliação do(s) autor(es):
[1] Inst Technol Res IPT, BR-05508901 Sao Paulo - Brazil
[2] EEIMVR Fed Fluminense Univ, BR-27255125 Volta Redonda, RJ - Brazil
[3] Nucl & Energy Res Inst IPEN, BR-05508000 Sao Paulo - Brazil
[4] Univ Sao Paulo, BR-05508901 Sao Paulo - Brazil
Número total de Afiliações: 4
Tipo de documento: Artigo Científico
Fonte: Powder Technology; v. 224, p. 291-296, JUL 2012.
Citações Web of Science: 10
Resumo

The effects of the compaction step on the (micro)structural features and aging behavior of polymer coated NdFeB-based bonded magnets is reported. Due to the fracture of the material during pressing, it is estimated an increase of at least 14% in the particles' area which is not coated. Such uncoated surfaces, when exposed to the environment, reduce the magnetic performance of the magnets aged/cured in air by 19% in the conditions evaluated in this investigation. Furthermore, XRD results interpreted by Rietveld analyses show a lattice parameter change in the tetragonal structure of the hard magnetic phase after pressing. Such change varies as a function of the height of the compacted part and it is ascribed to macro-elastic stress arising from the pressure distribution in the magnet. An aging/curing step during 24 h is able to relief such macro-elastic stress. (C) 2012 Elsevier B.V. All rights reserved. (AU)

Processo FAPESP: 10/08018-8 - Reprocessamento de ímãs sinterizados comerciais de TRFeB para a preparação de magnetos aglomerados e de compostos magnéticos semiduros utilizando hidrogênio
Beneficiário:Élio Alberto Périgo
Linha de fomento: Bolsas no Brasil - Pós-Doutorado