15:35 〜 15:55
[14E-T16-02] Field Assisted Sintering in the Direct Recycling of Hot Deformed Nd-Fe-B Magnet Scrap
キーワード:permanent magnets, circular economy, field assisted sintering, recycling
Recycling of Nd-Fe-B magnets is an ongoing challenge for the goal of a circular economy. State-of-the-art magnet production methods have limitations with respect to direct recycling of magnet scrap particles. Recent work has shown that a combination of pre-sintering by Field Assisted Sintering Technology/Spark Plasma Sintering (FAST/SPS) and hot deformation by Flash Spark Plasma Sintering (Flash SPS) has the potential to directly produce Nd-Fe-B magnets from 100% scrap material. A systematic study was done consolidating recycled magnet particles into a Flash SPS deformed magnet, using a range of weight percentages of scrap material and scrap particle size fractions. For example, HcJ of >1400 kAm-1 and Br of 1.1 T could be achieved with 20 wt.% scrap material. The relationship between particle size fraction, oxygen uptake, and percentage of recyclate in a final magnet are all explored and discussed with respect to magnets made from pristine material.