Effect of Compaction Pressure on the Hysteresis Loop of NdFeB Bonded Magnets

Abstract:

Compression moulded NdFeB bonded magnets can advantageously replace the sintered version in applications that require specific shape and size. The maximum densities that can be obtained for ready-to-press commercial raw materials are close to 6.0 g/cm³. For large pieces, uniaxially pressed, densities should be limited to values as 5.0 g/cm³ due to the friction during compression. This paper investigate the effects of final density (ranging from 5.0 to 6.0 g/cm³) on the magnetic of compression moulded magnets. A ready-to-press Magnequench MQPB+ was used as raw material. Small cylindrical samples were produced by press and cure. Results are presented and discussed considering aspects related to relative densities. The magnetic properties are dependent of density, and coercivity decreases with deformation during compaction.

• Periodical: Materials Science Forum (Volume 899)
• Pages: 576-580
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.899.576
• Online since: July 2017
• Authors: Daniel Rodrigues*, Gilberto Vicente Concílio, Jose Adilson de Castro, Marcos Flavio de Campos
• Keywords: Bonded Magnets, Magnetic Materials, NdFeB, Rare Earth Magnets

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