Effects of Transverse Field Annealing to Ribbon Axis and Wall-pinninng Annealing on High-frequency Magnetic Properties of Co-Based Amorphous Cores.

点击翻译按钮获取中文摘要

High-frequency magnetic properties of Co-based amorphous cores with transverse field annealing and wall pinning annealing were studied and magnetization process based on domain observation were discussed The samples used were zero magnetostrictive (Fe-Co)_x (Si_y-B_<1-y>)_<100-y>, (x=77-79, y=0.4-0.6) toroidal ribbon cores. To induce the anisotropy, the samples were annealed at 300ﾟC for 20 min.in a field 600 Oe in the transverse direction of ribbons, and to retrains the wall displacement, these cores were annealed subsequetly in a remanent state at 300ﾟC for 20 min. The wall pinninng treatment decreased the core loss markedly and also improved the high frequencyproperties of permeability.The results obtained were as follows,(1) In the case of (Fe-Co)_<79> (Si_<0.1>B_<0.9>)_<21> ribbons, the losses of the cores with the pinned wall were 60% and 40% of those of with the transverse anisotropy at 100 kHz and 5MHz, respectivery.(2) In addition, for the samples after the wall pinning annealing, the high frequency characteristics of initial permeability were improved in the range of above 1 MHz.(3) The resraint of the wall displacement and the magenitization rotation for these samples were observed by a Kerr microscope and their relation to the magnetic properties were dicussed.