Effect of Silica Coating on Particle Shape and Magnetic Properties of Iron Powder(I)

실리카 피착이 철립말의 입자형태 및 자기특성에 미치는 영향 (제1보)

  • 오재희 (인하대학교 공과대학 무기재료공학과) ;
  • 김종식 (인하대학교 공과대학 무기재료공학과) ;
  • 류병환 (인하대학교 공과대학 무기재료공학과)
  • Published : 1985.06.01

Abstract

The properties of magnetic recording materials largely depend on their shape magnetic anisotropy. The control of their shape and size distribution is very important for improving magnetic properties. The silica-coated goethite$(SiO_2$/$\alpha$-FeOOH=1.5wt%) having acicular shape was prepared. The sillica-coated goethite was heat-treated at 40$0^{\circ}C$~1,00$0^{\circ}C$ 1hr and then reduced at 50$0^{\circ}C$ 2hr. When the silica-coated goethite was heat-treated at 80$0^{\circ}C$ its acicular shape was maintained and its magnetic properties were improved(Hc: 1,325 Oe $\sigma$m:138.8 emu/g, Rs:0.56) However the acicular shape of the paricles was broken for non-coated hematite obtained by dehydration at 80$0^{\circ}C$ They were sintered and showed poor magnetic properties.

Keywords

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