Optimizing the Heat Treatment of Rare Earth-Transition Metal Sintered Magnets

Abstract:

Rare earth transition metals magnets, as for example SmCo5, NdFeB and Sm(CoCuFeZr)z magnets are, very often, submitted to a post-sintering heat treatment where the coercivity increases. In many cases, a slow cooling between the sintering and the annealing temperatures is applied. To optimize the time and cooling rate of heat treatment, it was developed a model using the finite volume method. This model takes into account the diffusivities of the different atom species and also the boundaries of phase diagrams.

• Periodical: Materials Science Forum (Volumes 660-661)
• Pages: 290-295
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.660-661.290
• Online since: October 2010
• Authors: Marcos Flavio de Campos, José Adilson de Castro
• Keywords: Coercivity, Diffusion, Heat Treatment, Magnet

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