Effects of Heat Treatment on Magnetic Properties of NdFeB Based Permanent Magnet Alloys

Abstract

In this study, the effect of flash annealing heat treatment applied at 680 oC for 5 minutes on the magnetic properties of NdFeB-based permanent magnet alloys produced by melt spinning method, which is one of the fast solidification methods, was investigated by using a very fast heating and cooling rate of 300 K/s. The obtained results showed that there was a remarkable improvement in the magnetic properties of the alloys with the applied heat treatment. Mainly, the hard magnetic properties were optimized by enhancing magnetic remanence from 21.64 emu/g to 55.76 emu/g, magnetic coercivity from 1184.15 Oe to 9146.30 Oe, and maximum energy product from 4.06 kJ/m3 to 62.02 kJ/m3 respectively.

Keywords

• NdFeB alloys
• Melt spinning
• Heat treatment
• Magnetic properties.

Kaynakça

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