Formation of anti-shell/core structure of heavy rare earth elements (Tb, Dy) in sintered Nd-Fe-B magnet after grain boundary diffusion process. (1st April 2019)

• Record Type: Journal Article
• Authors: Li, Weidong; Zhang, Qingke; Zhu, Qihang; Xiao, Song; Xu, Cheng; Yang, Lijing; Zheng, Bizhang; Mao, Shoudong; Song, Zhenlun
• Is Part Of: Scripta materialia. Number 163(2019)
• Page Start: 40
• Page End: 43
• Publication Date: 2019-04-01
• Subjects: Sintered Nd-Fe-B magnet -- Magnetron sputtering -- Heavy rare earth elements -- Grain boundary diffusion process -- Anti-shell/core structure; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2018.12.034
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: The evolution of microstructure close to the surface of sintered Nd-Fe-B magnet after grain boundary diffusion process (GBDP) of heavy rare earth elements (HREE, Tb, Dy) was investigated. It was found that two new types of microstructure, anti-shell/core and no-shell structures, were formed in the magnet with the diffusion time longer than 0.5 h. The anti-shell/core structure was formed due to an abnormal diffusion of HREE from grain to grain boundary based on the dual-trend diffusion model, it contributes a negative effect on the coercivity of diffused magnets. Graphical abstract: Unlabelled Image