Coercivity enhancement of hot-deformed Nd-Fe-B magnets by the eutectic grain boundary diffusion process using Nd₆₂Dy₂₀Al₁₈ alloy

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• 作者：Lihua Liu^a ; ^b ; H. Sepehri-Amin^a ; T. Ohkubo^a ; M. Yano^c ; A. Kato^c ; N. Sakuma^c ; T. Shoji^c ; K. Hono^a ; ^b ; ^{kazuhiro.hono@nims.go.jp}
• 关键词：Permanent magnets ; Nd-Fe-B ; Coercivity ; Hot-deformed magnets
• 刊名：Scripta Materialia
• 出版年：2017
• 出版时间：1 March 2017
• 年：2017
• 卷：129
• 期：Complete
• 页码：44-47
• 全文大小：957 K
• 卷排序：129

文摘

The eutectic grain boundary diffusion process was applied to a 2-mm-thick hot-deformed Nd-Fe-B magnets using Nd62Dy20Al18 alloy as a diffusion source, realizing the coercivity enhancement from 0.91 T to 2.75 T with relatively small remanence deterioration from 1.50 T to 1.30 T. In contrast, the conventional grain boundary diffusion process using Dy-vapor resulted in the degradation of coercivity as the grains are catastrophically coarsened at the processing temperature of 900 °C. Scanning transmission electron microscopy showed the formation of Dy-rich shell at the sides of the Nd2Fe14B grains and the diffusion of Al into the Nd2Fe14B grains, explaining the significant improvement in coercivity.