NiZn Ferrite Coating for Electrical Insulation of MnZn Ferrite Cores

Kitamoto, Y.; Yajima, H.; Nakayama, Y.; Abe, M.; Kitamoto, Y.; Yajima, H.; Nakayama, Y.; Abe, M.

J. Korean Ceram. Soc. > Volume 38(6); 2001 > Article

Journal of the Korean Ceramic Society 2001;38(6): 506.

Y. Kitamoto, H. Yajima, Y. Nakayama, M. Abe

Department of Physical Electronics, Tokyo Institute of Technology

ABSTRACT

The ferrite plating with applying power ultrasound waves of 19.5 kHz and 600W enabled us to encapsulate entirely MnZn ferrite cores for transformers with Ni$sub$x/Zn$sub$y/Fe$sub$3-x-y/O$_4$coating. Supplying a NH$_4$OH solution during the plating broke the limit of the solubility of Ni ions to ferrite-plated films. The electrical resistivity of the NiZn ferrite coating increased with increasing the Ni and Zn content, reaching 2.3${times}$10$^$5/Ωcm at the composition of Ni$sub$0.24/Zn$sub$0.30/Fe$sub$2.46/O$_4$. The saturation magnetization was 540 emu/㎤. As a result, the MnZn ferrite cores were successfully encapsulated with the NiZn ferrite coatings for an insulation layer.

Key words: Ultrasound waves, Ferrite plating, NiZn ferrite, Electrical insulation, Ferrite core