Effect of Dy Content Variation on Grain Boundary Diffusion of Nd-Fe-B Base Magnet
Several Nd-Fe-B sintered magnet samples with different Dy contents which ranges from 0%~4.00%(mass percent)were prepared and were used as base magnets for Dy GBDP(Grain boundary diffusion process).The magnetic properties,chemical composition and microstructure of the samples were analyzed and compared.It is found that the coercivity of the samples all increase 200-300 kA/m and Dy contents increase 0.30%-0.35%(mass percent),but the increments are not controlled by Dy content in base magnet directly.A further investigation show that,the Hcj increments are not proportional to the Dy increments,and the Hcj increase rate per Dy amount decreases gradually along with the increase of Dy content in base magnets.Considering another factor-EPMA Dy mapping images,Dy diffusion in Dy-free magnet results in a critical transformation of grain boundary structure,which is transformed from Dy-free structure to Dy-containing structure,and it makes the highest Hcj increase rate.
Nd-Fe-B sintered magnet GBDP coercivity Dy content base magnet
Cheng Xinghua Li Jian Zhou Lei Liu Tao Yu Xiaojun
Central Iron and Steel Research Institute,Beijing 100081,China;Advanced Technology and Materials Co. Advanced Technology and Materials Co.,Ltd.,Beijing 100081,China
国际会议
北京
英文
1394-1397
2018-09-16（万方平台首次上网日期，不代表论文的发表时间）