Directional annealing-induced texture in melt-spun (Sm₁₂Co₈₈)₉₉Nb₁ alloy

Authors

Tanjore V. Jayaraman, University of Nebraska-LincolnFollow
P. Rogge, University of Nebraska-Lincoln
Jeffrey E. Shield, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

2010

Comments

Published in Journal of Physics D: Applied Physics 43 (2010), 272004 (5pp); doi:10.1088/0022-3727/43/27/272004 Copyright © 2010 IOP Publishing Ltd. Used by permission.

Abstract

Developing texture in nanocrystalline permanent magnet alloys is of significant importance. Directional annealing is shown to produce texture in the permanent magnet alloy (Sm₁₂Co₈₈)₉₉Nb₁. Melt spinning produced isotropic grain structures of the hard magnetic metastable SmCo₇ phase, with grain sizes of ∼300 nm. Conventional annealing of melt-spun (Sm₁₂Co₈₈)₉₉Nb₁ alloy produced Sm₂Co₁₇ phase with random crystallographic orientation. Directional annealing of melt-spun (Sm₁₂Co₈₈)₉₉Nb₁ alloy, with appropriate combinations of annealing temperature and translational velocity, produced Sm₂Co₁₇ phase with (0 0 0 6) in-plane texture, as determined by x-ray diffraction analysis and magnetic measurements. The magnetization results show out-of-plane remanence higher than the in-plane remanence resulting in the degree of ‘magnetic’ texture in the order of 25–40%. Coercivity values above 2 kOe were maintained. The texture development via directional annealing while minimizing exposure to elevated temperatures provides a new route to anisotropic high-energy permanent magnets.