Assembly of uniaxially aligned rare-earth-free nanomagnets

Journal Article · Mon Sep 17 04:00:00 EDT 2012 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4753950· OSTI ID:1211313

Balamurugan, B; Das, B; Shah, VR; Skomski, R; Li, XZ; Sellmyer, DJ

We report HfCo7 nanoparticles with appreciable permanent-magnet properties (magnetocrystalline anisotropy K-1 approximate to 10 Mergs/cm(3), coercivity H-c approximate to 4.4 kOe, and magnetic polarization J(s) approximate to 10.9 kG at 300 K) deposited by a single-step cluster-deposition method. The direct crystalline-ordering of nanoparticles during the gas-aggregation process, without the requirement of a high-temperature thermal annealing, provides an unique opportunity to align their easy axes uniaxially by applying a magnetic field of about 5 kOe prior to deposition, and subsequently to fabricate exchange-coupled nanocomposites having J(s) as high as 16.6 kG by co-depositing soft magnetic Fe-Co. This study suggests HfCo7 as a promising rare-earth-free permanent-magnet alloy, which is important for mitigating the critical-materials aspects of rare-earth elements. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4753950]

• Sponsoring Organization: USDOE Advanced Research Projects Agency - Energy (ARPA-E)
• DOE Contract Number: AR0000046
• OSTI ID: 1211313
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 12 Vol. 101; ISSN 0003-6951
• Country of Publication: United States
• Language: English