Study on the Preparation of Ferrite Powder for Bonded Magnets

본드 자석용 페라이트 분말의 제조에 관한 연구

  • 진성빈 (명지대학교 전자공학과) ;
  • 임재근 (명지대학교 전자공학과) ;
  • 문현욱 (명지대학교 전자공학과) ;
  • 신용진 (명지대학교 전자공학과)
  • Published : 1994.11.01

Abstract

This paper describes study on the preparation of ferrite powder for bonded mallets. The specimen which has the basic composition of SrO$.$nF$_2$O$_3$ with n=5.9 is in nonstoichiomatric region. Calcination is performed under N$_2$ atmosphere 1175$^{\circ}C$, 1200$^{\circ}C$, 1225$^{\circ}C$, 1250$^{\circ}C$ and 1275$^{\circ}C$ respectively. Then, Cooling is carried out in the furnace. In order to increase coecivity and obtain uniform grain size, we add to the specimen 0.7wt%CaCO$_3$, 0.3wt % SiO$_2$, 0.5wt%Na$_2$SiO$_3$ and 0.5wr% Al$_2$O$_3$. Also, in order to increase milling effect, carbon coating on sample particles is tried. As the result, single magnetic domain partic1e with Size of 1$\mu\textrm{m}$ in obtained and magnetic properties are improved.

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