Microstructure and Magnetic Properties of Hot-Pressed and Hot-Deformed Composite Magnets Produced by Spark Plasma Sintering Method

Abstract:

Bulk isotropic and anisotropic Nd_13.5Fe_80.4Ga_0.5B_5.6 and Nd_13.5Fe_80.4Ga_0.5B_5.6/Fe magnets were synthesized by applying spark plasma sintering (SPS) technique. The effect of hot-pressing temperature on the magnetic properties of hot-pressed (HP) and hot-deformed (HD) magnets without additive and with 5% Fe addition was investigated. With increasing sintering temperature for HP magnets, the grain grew gradually. For HD magnets, the optimal magnetic properties could be obtained at hot-pressing temperature 680°C due to the development of desired c-axis texture and uniform microstructure, which resulted from the appropriate and uniform grain size in HP magnets. Fe addition could enhance remanence (B_r) and magnetic energy products ((BH)_m) of HP and HD magnets. However, the maximum magnetic energy product of HD magnets decreased when hot-pressing temperature was higher than 650°C.

• Periodical: Materials Science Forum (Volume 686)
• Pages: 740-744
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.686.740
• Online since: June 2011
• Authors: Yi Long Ma, Deng Ming Chen, Qian Shen, Peng Jun Cao
• Keywords: Composite Magnets, Hot Deformation, Magnetic Property, Microstructure

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