Soft magnetic properties of rapidly-annealed nanocrystalline Fe-Nb-B-(Cu) alloys

JOURNAL OF ALLOYS AND COMPOUNDS

卷:723

Article

Parsons, R.¹  Zang, B.¹  Onodera, K.²  Kishimoto, H.²  Kato, A.²  Suzuki, K.¹ 

[1] Monash Univ, Dept Mat Sci & Engn, Clayton, Vic 3800, Australia

[2] Toyota Motor Co Ltd, Mishu Ku, Shizuoka 4101193, Japan

关键词: Rapid annealing;    Induced anisotropy;    Nanoperm;    Soft magnetic materials;    Nanocrystalline alloys;    Amorphous alloys;   

DOI  :  10.1016/j.jallcom.2017.06.208

来源: Elsevier

【 摘 要 】

Nanocrystalline Fe-M-B (M = Zr or Nb) alloys (Nanoperm) exhibit excellent soft magnetic properties when M content is 6-7 at%. Lowering the M content below 4 at% usually results in a coarsening of the nanocrystallites and so sets a lower limit on the M content for Nanoperm. In this report we have demonstrated that a highly refined, magnetically soft nanostructure can be achieved for Fe-Nb-B-(Cu) alloys with a Nb content well below 4 at% by employing a rapid annealing process which utilises a heating rate of 150 K s(-1). The low Nb-content of these nanocrystalline alloys brings about a high saturation magnetic polarization of 1.85-1.9 T, well above the upper limit of Nanoperm (1.7 T). These newly developed, bcc-Fe based nanocrystalline soft magnetic alloys which have an M content lower than 4 at% are named HiB-Nanoperm. HiB-Nanoperm exhibits excellent soft magnetic properties with a coercivity as low as 2.5 A m(-1) and a high initial permeability of similar to 10(4) at 1 kHz. A possible explanation for the rapid annealing induced grain refinement observed for this Fe-M-B system is that the higher annealing temperatures used by this process bring about a lowering of the precursor amorphous phase viscosity which then triggers homogeneous nucleation, thereby considerably increasing the number density of bcc-Fe nucleation sites. (C) 2017 Elsevier B.V. All rights reserved.

【 授权许可】

Free