• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.94-96
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• 1995

• Proceedings of the Korean Magnestics Society Conference
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• 1996.05a
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• pp.44-45
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• 1996

• Journal of the Korean Magnetics Society
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• v.26 no.6
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• pp.196-200
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• 2016

In this study the mechanisms of magnetization reversal and magnetic interaction effects on activation volumes for Sr-ferrite with different particle sizes are investigated. The activation volumes of C2 sample are larger than those of C3 sample in the range of low magnetic fields. But the fields above the coercivity of sample C2, the activation volumes of both samples are decreased linearly with increasing the applied magnetic field. These phenomena can be explained by the strengths of two critical fields representing the reverse domain nucleation field and the domain wall pinning field as well as the strength of dipolar interaction.

• Journal of Energy Engineering
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• v.8 no.1
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• pp.137-142
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• 1999

지구 온난화 현상의 주된 원인인 CO2 가스의 분해를 위해, 스트론튬 페라이트를 이용한 CO2 가스 분해 반응에 대해 연구하였다. CO2 가스 분해를 위한 반응 매체로 스피넬형 조성과 마그네토프롬바이트형 조성의 스트론튬 페라이트 미세분말을 공침법으로 제조한 후, H2 가스로 환원시켜 산소부족형 스트론튬 페라이트 분말을 제조하였다. 이 산소부족형 스트론튬 페라이트 분말은 CO2 가스를 환원, 분해시키면서 산화된다. 이러한 원리를 이용한 CO2 분해 반응에서 스피넬형 조성 스트론튬 페라이트 분말이 마그네토프롬바이트형 조성 분말 보다 빠르게 많은 양의 CO2 가스를 분해 시켰다. 페라이트 중의 스트론튬이 산화·환원 반응을 촉진시키는 것을 관찰할 수 있었다.

• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.116-117
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• 2002

High energy mi]ling은 mechanical alloying을 일컫는 분말 제조 공정으로서 금속 뿐 아니라 세라믹스 분말 합성에도 많이 응용되고 있으며, 입자크기의 나노화와 일반적인 세라믹 분말의 특성을 개질할 수 있다는 특징을 갖고 있어서 다양한 연구 결과가 보고되고 있다[1-2]. Ba 및 Sr 페라이트와 같은 육방정 페라이트는 보자력(high coercivity)이 높은 특성을 가지므로 영구자석용, 기록재료용 등으로 광범위하게 사용되어온 재료이다. 이와 같은 높은 보자력을 유지하기 위해서는 입자크기가 단자구 입경(<1 $\mu\textrm{m}$) 보다 작아야 하기 때문에, 초미립자 합성에 관한 많은 연구가 진행되어 왔다[3-4]. (중략)

• Proceedings of the KWS Conference
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• 2000.10a
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• pp.240-242
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• 2000

This study was investigated absorption properties of electromagnetic wave in thermal sprayed Sr-ferrite coatings. The experiment of this study was ; manufactured thermal spraying powder for improving absorption-efficiency, processed for increasing strength of thermal spray coatings, and measured the electromagnetic wave shielding efficiency. This study was obtained excellent absorption-efficiency by thermal sprayed Sr-ferrite coatings.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.82-85
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• 2002

High-quality Sr-ferrite sintered magnets have been studied by using mill scale added SrCO$_3$ and oxidents before oxidation process. The pre-added SrCO$_3$ powders were improved the degree of oxidation and crush of mill scale and the magnetic properties of Sr-ferrite sintered magnets. The small added NaNO$_3$ oxidant was also highly improved the degree of oxidation and crush of mill scale and the magnetic properties of Sr-ferrite sintered magnets; 3805 G of remanent flux density, 3240 Oe of intrinsic coercivity, and 3.45 MGOe of maximum energy product.

• Journal of the Korean Ceramic Society
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• v.28 no.6
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• pp.471-477
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• 1991

Effects of ZnO, PbO and SiO2 on the grain growth and magnetic properties of Sr-ferrite were investigated. (1) Addition of ZnO to Sr-ferrite increased remanence, but decreased coercivity and maximum energy product. (2) Addition of PbO up to 0.5 wt% increased (B$.$H)max of Sr-ferrite, but addition more than 0.5 wt% decreased (B$.$H)mzx (3) SiO2 addition to the 0.5 wt% PbO doped Sr-ferrite decreased remanence and increased coercivity. The coercivity increase in due to the grain refinement effect of SiO2. But addition of SiO2 more than 0.5 wt% invoked a decrease of coercivity and (B$.$H)max of Sr-ferrite due to abnormal grain growth. Sr-ferrite magnet having maximum energy product of 3.7MGOe was fabricated by using the roasting product of Pyrrhotite.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.102-104
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• 1995

• Proceedings of the Korean Magnestics Society Conference
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• 2016.11a
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• pp.85-86
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• 2016