Preferential Co and Fe atom occupancy in R2(Fe1-xCox)14B intermetallic compounds (R = Nd, Y and Ce)

JOURNAL OF ALLOYS AND COMPOUNDS

卷:851

Article

Eslava, Gabriel Gomez¹  Ito, Masaaki²  Colin, Claire, V¹  Yano, Masao²  Shoji, Tetsuya²  Kato, Akira²  Suard, Emmanuelle³  Dempsey, Nora M.¹  Givord, Dominique¹ 

[1] Univ Grenoble Alpes, Inst Neel, Grenoble INP, F-38000 Grenoble, France

[2] Toyota Motor Co Ltd, Adv Mat Engn Div, Susono 4101193, Japan

[3] Inst Laue Langevin ILL, F-38000 Grenoble, France

关键词: Permanent magnets;    Preferential site occupancy;    Crystal structure;    Neutron powder diffraction;    Magnetocrystalline anisotropy;   

DOI  :  10.1016/j.jallcom.2020.156168

来源: Elsevier

【 摘 要 】

A powder neutron scattering study of atom substitution in Nd-2(Fe1-xCox)(14)B, Y-2(Fe1-xCox)(14)B and Ce-2(Fe1-xCox)(14)B compounds is presented. Compared to previous studies, this one benefits from the considerable progress made in neutron diffraction measurements and their analysis during the last 15 years. The normalization of the occupancy values to those expected for a random distribution permits to reveal small deviations from random distribution. On all crystallographic sites some preferential occupancy is evidenced, the extent of which depends on the Co versus Fe content. A statistical model quantitatively describing site occupancies is proposed, which allows us to study the extreme cases of very dilute substitutions. Steric considerations primarily determine atom substitution, more particularly Fe-substitution in Co-rich compounds. The enthalpy of mixing must also be considered to describe Co preferential occupancies more exactly. (C) 2020 Elsevier B.V. All rights reserved.

【 授权许可】

Free