Grain Growth Kinetics of (NdPr)₂Fe₁₄B Magnets

Abstract:

Two different effects need to be considered in the sintering: (i) The densification should be maximum, to optimize the energy product BHmax and the remanence, however, (ii) the .grain size should be small, in order to maximize the coercivity. Grain growth takes place during the sintering step of the magnets, usually performed at the range 1000-1100°C. In this study, the grain growth kinetics is investigated. Samples of NdPrFeB magnets (proportion 3 Nd : 1 Pr) were heat treated at the temperature of 1050 °C, for times between 1 to 12 hours. The knowledge of the grain growth and coarsening kinetics allows extrapolation to other temperatures, and this information is helpful to maximize coercivity and remanence at the same time.

• Periodical: Materials Science Forum (Volume 802)
• Pages: 540-545
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.802.540
• Online since: December 2014
• Authors: Kaio Sérgio Torres de Souza, Célio de Jesus Marcelo, Daniel Rodrigues, José Adilson de Castro, Marcos Flavio de Campos*
• Keywords: Grain Size, Magnets, NdFeB, Sintering

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