Geometry Dependence of Magnetization Reversal in Nanocomposite Alloys

Journal Article · Sat May 31 00:00:00 EDT 2014 · Journal of The Minerals, Metals & Materials Society

DOI:https://doi.org/10.1007/s11837-014-1005-0· OSTI ID:1211002

Skomski, R; Manchanda, P; Takeuchi, I; Cui, J

The geometrical optimization of aligned hard-soft permanent-magnet nanocomposites is investigated by model calculations. Considered criteria are the shapes of the soft and c-axis-aligned hard phases, the packing fraction of the soft phase, and magnetostatic interactions. Taking into account that the energy product is enhanced via the volume fraction of the soft phase, subject to maintaining coercivity, we find that the best structures are soft-magnetic cubes as well as long rods with a square cross section. Comparing embedded soft cubes with embedded soft spheres of the same size, our nucleation-field analysis shows that the volume fraction of the soft phase is enhanced by 91%, with a coercivity reduction of only 25%. Magnetostatic interactions often but not always deteriorate the permanent-magnet performance, as exemplified by the example of MnBi:FeCo bilayers and multilayers.

• Sponsoring Organization: USDOE Advanced Research Projects Agency - Energy (ARPA-E)
• OSTI ID: 1211002
• Journal Information: Journal of The Minerals, Metals & Materials Society, Vol. 66, Issue 7; ISSN 1047-4838
• Country of Publication: United States
• Language: English