Influence of Hot-Pressing on Sintered Nd-Fe-B Permanent Magnets

Abstract:

In this work, we perform a post hot-pressing on the pre-sintered Nd-Fe-B magnet, and investigate its influences. The results show that the main influence on the magnetic characteristics is that it deteriorates the rectangularity of the demagnetization curves. Further investigations on density, grain size and crystal alignment show that the increases of density and grain size, and the decrease of crystal alignment with the hot-pressing. The discussion indicates that at the temperature higher than the melting point of boundary phase, the liquefying of boundary under uniaxial external pressure brings about the grain growth, the density increase, and the deviation of crystal alignment from the pre-aligned optimum position.

• Periodical: Key Engineering Materials (Volume 538)
• Pages: 223-226
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.538.223
• Online since: January 2013
• Authors: Qi Jun Huang, Zhi Qin Liao, Wei Jin Yan, Feng Xu, Guang Chen, Shan Dong Li
• Keywords: Crystalline Alignment, Density, Hot-Pressing, Sintered Nd-Fe-B Magnet

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