Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7994844 | Journal of Alloys and Compounds | 2018 | 16 Pages |
Abstract
In this study, we presented an effective approach for the substantial coercivity enhancement of Dy-free sintered Nd-Fe-B magnets with Ga-doping. The coercivity was substantially enhanced from 10.1 kOe to 19.8 kOe by effective microstructure optimization and phase constitution regulation in antecedent alloys. A good isolation of 2:14:1 grains by Nd-rich intergranular phase is obtained in final magnets accompanying with the formation of intermetallic Nd6Fe13Ga phase. However, when dehydrogenating above 500 °C, masses of preformed Nd6Fe13Ga phases are detected in the initial strip casting alloys and the homologous magnet suffers an unanticipated degradation of coercivity. Magnetic domain observation and thermal magnetic analysis imply a pronounced difference in the magnetism of grain boundary (GB) phases, which closely associated with the composition homogeneity of Nd-rich phases in antecedent alloys. The mechanism of the coercivity variation in the sintered magnets with different GBs magnetism is discussed based on magnetic behavior analysis.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Guangfei Ding, Shuai Guo, Ling Chen, Jinghui Di, Jie Song, Renjie Chen, Don Lee, Aru Yan,