(Sm,Zr)Fe${}_{12-x}$M${}_x$ (M=Zr,Ti,Co) for permanent-magnet applications: Ab initio material design integrated with experimental characterization

Abstract

In rare-earth permanent magnets (REPM's), trade-off's between intrinsic magnetic properties are often encountered. A recent example is SmFe${}_{12}$ where excellent magnetic properties can be achieved at the sacrifice of bulk structure stability. Bulk structure stability is sustained by the presence of the third substitute element as is the case with SmFe${}_{11}$Ti, where Ti degrades magnetic properties. It is now in high demand to find out with which chemical composition a good compromise in the trade-off between structure stability and strong ferromagnetism is reached. We inspect the effects of representative substitute elements, Zr, Ti, and Co in SmFe${}_{12}$ by combining ab initio data with experimental data from neutron diffraction. The trend in the intrinsic properties with respect to the concentration of substitute elements are monitored and a systematic way to search the best compromise is constructed. A certain minimum amount of Ti is identified with respect to the added amount of Co and Zr. It is found that Zr brings about a positive effect on magnetization, in line with recent experimental developments, and we argue that this can be understood as an effective doping of extra electrons.

arXiv comment18 pages, 15 figures, all figures updated, confusion between figs. 13 (b) and 13 (f) corrected, confusion between between figs. 13 (m) and 13 (q) corrected, no change in the data, to appear in Phys. Rev. Applied

References in corpus (6)

• Temperature dependent magnetic anisotropy in metallic magnets from an ab-initio electronic structure theory: L1_0-ordered FePt
• First-principles study on stability and magnetism of NdFe11M and NdFe11MN for M=Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn
• Temperature-dependent magnetocrystalline anisotropy of rare earth/transition metal permanent magnets from first principles: The light RCo${}_5$ (R=Y, La-Gd) intermetallics
• Finding the structure of phosphorus in the phase IV
• Relevance of $4f$-$3d$ exchange to finite-temperature magnetism of rare-earth permanent magnets: an ab-initio-based spin model approach for NdFe${}_{12}$N
• Probability distribution of substituted Titanium in RT12 (R = Nd, Sm, T = Fe, Co) structures

Cited by in corpus (2)

• Lattice dynamics effects on finite-temperature stability of $R_{1-x}$Fe${}_x$ ($R$ = Y, Ce, Nd, Sm, and Dy) alloys from first principles
• Anisotropy at twin interfaces in $R{T}_{12}$ ($R$=rare earth, $T$=transition metal) magnets