Enhanced coercivity in thermally processed (Nd,Dy)(Fe,Co,Nb,B) _5.5/ α-Fe nanoscale multilayer magnets

Authors

• W. Liu, Shenyang National Laboratory for Materials Science, Institute of Metal Research, and International Centre for Materials Physics, Chinese Academy of Science, Shenyang 110016, People's Republic of China
• Xingzhong Li, University of Nebraska-LincolnFollow
• J Ping Liu, University of Texas at ArlingtonFollow
• X.K. Sun, Shenyang National Laboratory for Materials Science, Institute of Metal Research, and International Centre for Materials Physics, Chinese Academy of Science, Shenyang 110016, People's Republic of China
• C.L. Chen, Shenyang National Laboratory for Materials Science, Institute of Metal Research, and International Centre for Materials Physics, Chinese Academy of Science, Shenyang 110016, People's Republic of China
• Ralph Skomski, University of Nebraska-LincolnFollow
• Z.D. Zhang, Shenyang National Laboratory for Materials Science, Institute of Metal Research, and International Centre for Materials Physics, Chinese Academy of Science, Shenyang 110016, People's Republic of China
• David J. Sellmyer, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

5-15-2005

Comments

Published by American Institute of Physics. J. Applied Physics 97, 104308 (2005). ©2005 American Institute of Physics. Permission to use. http://jap.aip.org/jap/.

Abstract

Structural and magnetic properties of laminated (Nd,Dy)(Fe,Co,Nb,B)_5.5/Fe nanocomposites are investigated. Normally, the addition of the soft phase to the hard phase enhances the remanence but deteriorates the permanent-magnet performance of the material by reducing the coercivity. In the present system, the coercivity increases to 1608 kA/m (20.2 kOe) in thermally processed Nd–Dy–Fe–Co–Nb–B(15 nm)/Fe(4 nm) multilayered nanocomposites, which is higher than that of the single-layer hard-magnetic film. The abnormally high coercivity is achieved by annealing at relatively high temperature, which breaks the laminated structure of the as-deposited multilayer. A likely physical explanation of the enhanced coercivity is the introduction of the domain-wall pinning sites that counteract the inevitable decrease of the nucleation field.