Effect of Heat Treatment Time on Dy-Cu Alloy Diffusion Process in Dy-Containing Commercial Nd-Fe-B Sintered Magnets

• 来源期刊: 金属学报（英文版）
• 年，卷（期）: 2018,（5）
• 页码范围: 496-502
• 页数: 7页
• 语种: 英文

摘要

In this paper,the grain boundary diffusion process (GBDP) using a Dy70Cu30 (at.％) alloy as the diffusion source was performed in a commercial sintered Nd-Fe-B magnet,and the effect of heat treatment time on the microstructure and magnetic properties of the magnet was investigated in detail.For the processed magnets heat-treated at 860 ℃,as heat treatment time increased,the coercivity and the depth of (Nd,Dy)2Fe14B core-shell structure increased first and then decreased.However,when the heat treatment time was more than 2 h,the diffusion path of Dy from the Dy-rich shell phase into the Nd2Fe14B grains was revealed,and a nearly homogeneous (Nd,Dy)2Fe14B phase was formed,which brought on the decrease in both the depth of visible core-shell structure and the coercivity of Nd-Fe-B magnet.