• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 춘계학술대회 논문집
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• pp.23-27
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• 2004

GHz 대역용 전파흡수체의 개발에 있어 Cast Alnico magnets을 자성손실재로 이용하여 우수한 전파흡수특성을 나타내는 새로운 전파흡수체를 개발하였다. 특히 본 연구에서 개발한 전파흡수체는 폐처리된 Cast Alnico magnets을 이용한 것으로 이는 환경문제와 자원절약의 문제를 고려할 때 중요한 의미를 갖는다. 본 연구에서 개발한 Cast Aliico magnets을 이용한 전파흡수체는 X-band와 C-band를 고려한 전파흡수체로서 우수한 전파흡수특성 나타낸다.

• 한국전기전자재료학회논문지
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• 제23권12호
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• pp.988-995
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• 2010

In this study the (Alnico, Sm-Co) bonded magnets were fabricated by mixing the Sm-Co added alnico alloy powders with epoxy resin and binder, appropriately. Also, the hybrid ring magnets of (Alnico, Sm-Co)/Sr-ferrite were fabricated by coupling the Sr-ferrite composite layer with an (Alnico, Sm-Co) magnet. The magnetic properties of (Alnico, Sm-Co) ring magnets were varied with the amount of Sm-Co powders. The addition of Sm-Co powders increased a remanent induction($B_r$) and coercive force($_BH_C$), while decreasing a surface flux density and repulsive distance. The surface flux density and repulsive distance for the (Alnico, Sm-Co) ring magnet increased with a magnetizing voltage up to about 160 V and reached an apparent saturation point. Also, the measurements of temperature and moisture characteristics showed that the surface flux densities of N-S poles and repulsive distance decreased a little within 4% after 10 days passed.

• Journal of electromagnetic engineering and science
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• 제5권3호
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• pp.117-121
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• 2005

We compared electromagnetic(EM) wave absorption properties between Alnico magnet (A) and (B) with different magnetic properties. Also, we investigated the effect of carbon, thickness of absorbers, and Alnico contents on EM wave absorption, and clarified the relation between Alnico content and central frequency.

• 한국항해항만학회지
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• 제29권2호
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• pp.147-150
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• 2005

We suggest a cast Alnico magnet as a new microwave absorber. The proposed Alnico microwave absorber shows advanced microwave absorption properties of 24 dB at 13.3 GHz for the thicknesses of 1 mm We also investigated the effects of the carbon, which qjfects strongly to microwave absorption in Alnico magnet microwave absorbers. Central frequency shifts toward lower frequency with increasing Alnico content which is related to the frequency to show tan 8 > 1. Also, we investigated the sample thickness dependence on the microwave absorption properties.

• 대한금속재료학회지
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• 제49권1호
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• pp.85-91
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• 2011

Alnico magnets can be used as magnetic bearings for the precise electric power measuring instruments such as watt-hour meters because they have high remanence ($B_r$), relatively high maximum energy product ($(BH)_{max}$), and excellent temperature stability. In this study, Alnico composite magnets were fabricated by appropriately mixing alnico alloy powders with epoxy resin and binder. The Alnico powders mixed with epoxy resin and a hardening agent with a mixing ratio of 96:4 were pressed and then cured to be a toroid-type ring magnet with an outer diameter (${\Phi}_{out}$) of 15 mm, an inner diameter (${\Phi}_{in}$) of 6.5 mm and a thickness (t) of 2.5 mm, respectively. The magnetic properties of the Alnico ring magnets were varied with the mixing ratio of Alnico powders that possess different average particle sizes. The Alnico ring magnet prepared by mixing 5 wt% of $50{\mu}m$ (small size) powder, 15~20 wt% of $150{\mu}m$ (medium size) powder, and 75~80 wt% of $300{\mu}m$ (large size) powder showed the best magnetic properties (remanent induction, coercive force, maximum energy product, and surface flux density). In addition, measurements of temperature and moisture characteristics for the Alnico ring magnets showed that the surface flux densities of the N and S poles decreased little and the repulsive distance between the magnets decreased as small as 0.05 mm after 10 days.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1999년도 추계학술발표강연 및 논문개요집
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• pp.106-106
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• 1999

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1993년도 춘계연구발표회 논문개요집
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• pp.68-69
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• 1993

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1994년도 춘계연구발표회 논문개요집
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• pp.64-65
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• 1994