Influence of Dysprosium Compounds on the Extraction Behavior of Dy from Nd-Dy-Fe-B Magnet Using Liquid Magnesium

Metals

卷:11

Do-Hyang Kim¹  Taek-Soo Kim²  Sang-Min Park²  Sun-Woo Nam²  Mohammad Zarar Rasheed²  Myung-Suk Song² 

[1] Department of Materials Science and Engineering, Yonsei University, Seoul 03722, Korea;

[2] Research Institute of Advanced Manufacturing Technology, Korea Institute of Industrial Technology, 12, Gaetbeol-ro, Incheon 21999, Korea;

关键词: recycling;    pyrometallurgy;    dysprosium;    liquid metal extraction;    phase transformation;   

DOI  :  10.3390/met11091345

来源: DOAJ

【 摘 要 】

During the liquid metal extraction reaction between a Nd-Dy-Fe-B magnet and liquid Mg, Nd rapidly diffuses out of the magnet, whereas Dy is not extracted due to the reaction with the matrix and the formation of Dy₂Fe₁₇ phase. In addition, theDy₂O₃ phase exists at the grain boundaries. Until now, only the effect of the Dy₂O₃ phase on the extraction of Dy has been reported. In this study, the effect of the Dy₂Fe₁₇ phase on the extraction of Dy from the Nd-Dy-Fe-B magnet was investigated in liquid Mg. The formation of the Dy₂Fe₁₇ phase during the reaction between Mg and matrix (RE₂Fe₁₄B) was first examined using a thermodynamical approach and confirmed by microstructural analysis. It was observed that Dy extraction was dominated by Dy₂Fe₁₇ phase decomposition from 3 h to 24 h, followed by Dy₂O₃ phase dominant reaction with Mg. Comparing the activities of the Dy₂Fe₁₇ phase and the Dy₂O₃ phase, the reaction of Dy₂Fe₁₇ is dominant, as compared to the Dy₂O₃ phase. Finally, at 48 h, the high Dy extraction percentage of 93% was achieved. As a result, in was concluded that the Dy₂Fe₁₇ phase acts as an obstacle in the extraction of Dy. In the future, if research to control the Dy₂Fe₁₇ phase proceeds, it will be of great importance to advance the recycling of Dy.

【 授权许可】

Unknown