Effect of annealing on nanostructure and magnetic properties of Zr₂Co₁₁ material

Authors

Wenyong Zhang, University of Nebraska-LincolnFollow
Xingzhong Li, University of Nebraska-LincolnFollow
Shah R. Valloppilly, University of Nebraska-LincolnFollow
Ralph A. Skomski, University of Nebraska - LincolnFollow
David J. Sellmyer, University of Nebraska-LincolnFollow

Date of this Version

2014

Citation

Materials Science and Engineering B 186, 2014

Abstract

Single-phaseZr₂Co₁₁ nanomagnetic materials with high coercivity have been fabricated by melt spin-ning with subsequent annealing under Ar, N₂, and vacuum. Annealing coarsens the grains and de-creases the density of defects, leading to intergrain decoupling action and the enhancement of the magnetocrystalline anisotropy field of the hard magnetic phase. Therefore, coercivity increases 44.7% from 6.7 kOe for the as-spun to 9.7 kOe for the annealed, which is the highest among Zr–Co alloys so far. The results show that the magnetic-hardening mechanism is primarily dominated by domain-wall pinning. In addition, annealing clearly increases the saturation magnetization. The above results indicate that Zr₂Co₁₁ has potential for fabricating rare-earth-free permanent-magnet nanocomposites.