• Title/Summary/Keyword: Fe-Si-B-Nb-Cu

Search Result 77, Processing Time 0.033 seconds

MAGNETIC PROPERTIES OF $Fe_{73.5}Cu_1Nb_3Si_{15.5}B_7/Co_{88.3}Fe_{5.07}B_{3.44}Si_{3.19}$ TWO-PHASES RIBBON

  • Kim, W. B.;S. M. Hong;Kim, C. O.;Kim, C. G.
    • Proceedings of the Korean Magnestics Society Conference
    • /
    • 2002.12a
    • /
    • pp.198-199
    • /
    • 2002

  • 연자성 재료는 투자율이 높고, 큰 포화자속 밀도를 갖는 재료로서 외부자계에 용이하게 자화되며, 그 용도를 살펴보면 전기에너지 변환, 자기기록. 변압기, 변성기, 각종 코아, 모터, 자기센서, 전ㆍ자계차폐재등 많은 전자기기에 이용되고 있다. 따라서 연자성재료는 기본적으로 결정자기이방성과 자왜가 작아야 한다. 한편 전기, 전자기의 경량화 및 고효율화를 위하여서는 포화자속밀도의 극대화, 고주파영역에서의 우수한 연자기 특성 및 저에너지 손실을 갖는 재료개발이 요구된다. (중략)

  • PDF

Electromagnetic Wave Absorption Properties of Fe-based Nanocrystalline P/M sheets with Al2O3 additive (Al2O3 첨가에 따른 Fe계 나노결정립 P/M시트의 전자파 흡수특성)

  • Woo, S.J.;Cho, E.K.;Cho, H.J.;Lee, J.J.;Sohn, K.Y.;Park, W.W.
    • Journal of Powder Materials
    • /
    • v.14 no.4
    • /
    • pp.265-271
    • /
    • 2007

  • Electromagnetic wave absorbing materials have been developed to reduce electromagnetic interference (EMI) for electronic devices in recent years. In this study, Fe-Si-B-Nb-Cu base amorphous strip was pulverized using a jet mill and an attritor and heat-treated to get flake-shaped nanocrystalline powders, and then the powders were mixed, cast and dried with dielectric $Al_{2}O_{3}$ powders and binders. As a result, the addition of $Al_{2}O_{3}$ powders improved the absorbing properties of the sheets noticeably compared with those of the sheets without dielectric materials. The sheet mixed with 2 wt% $Al_{2}O_{3}$ powder showed the best electromagnetic wave absorption, which was caused by the increase of the permittivity and the electric resistance due to the dielectric materials finely dispersed on the Fe-based powder.

  • https://doi.org/10.4150/KPMI.2007.14.4.265 인용 PDF KSCI

The Characteristic Changes of Electromagnetic Wave Absorption in Fe-based Nanocrystalline P/M Sheets Mixed with Ball-Milled Carbon Nanotubes (Fe계 나노결정립 분말 시트에 첨가된 CNT의 볼밀 공정에 따른 전자파 흡수 특성 변화)

  • Kim, Sun-I;Kim, Mi-Rae;Sohn, Keun-Yong;Park, Won-Wook
    • Journal of Powder Materials
    • /
    • v.16 no.6
    • /
    • pp.424-430
    • /
    • 2009

  • Electromagnetic wave energies are consumed in the form of thermal energy, which is mainly caused by magnetic loss, dielectric loss and conductive loss. In this study, CNT was added to the nanocrystalline soft magnetic materials inducing a high magnetic loss, in order to improve the dielectric loss of the EM wave absorption sheet. Generally, the aspect ratio and the dispersion state of CNT can be changed by the pre-ball milling process, which affects the absorbing properties. After the various ball-milling processes, 1wt% of CNTs were mixed with the nanocrystalline $Fe_{73}Si_{16}B_7Nb_{3}Cu_1$ base powder, and then further processed to make EM absorption sheets. As a result, the addition of CNT to Fe-based nanocrystalline materials improved the absorption properties. However, the increase of ball-milling time for more than 1h was not desirable for the powder mixture, because the ballmilling caused the shortening of CNT length and the agglomeration of the CNT flakes.

  • https://doi.org/10.4150/KPMI.2009.16.6.424 인용 PDF KSCI