• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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• pp.53-58
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• 2002

Electrical insulation and mechanical properties of the plasma sprayed oxide ceramic coatings were studied before and after the sealing treatment of the ceramic coatings. Plasma sprayed A1$_2$O$_3$-TiO$_2$ coating as the reference coating was sealed using three commercial sealants based on polymer. Penetration depth of the sealants to the ceramic coating was evaluated directly from the optical microscope using a fluorescent dye. It is estimated that the penetration depth of the sealants to the ceramic coating is from 0.2 to 0.5 mm depending on the sealants used. The preliminary test results with a DC puncture tester imply that the dielectric breakdown voltage mechanism of plasma sprayed ceramic coatings has been determined to be a corona mechanism. Dielectric breakdown voltage of the as-sprayed and as-ground samples have shown a linear trend with regard to the thickness showing an average dielectric strength of 20 kV/mm for the thickness scale studied. It is also shown that grinding the coating before sealing and adding fluorescent dye do not agent the penetration depth of sealants. All of the microhardness, two-body abrasive wear resistance, bond strength, and surface roughness of the ceramic coating after the sealing treatment are improved. The extent of improvement is different from the sealants used. However, three-point bending stress of the ceramic coating after the sealing treatment is decreased. This is attributed to the reduced micro-crack toughening effect since the cracks propagate easily through the lamellar of the coating without crack deflection and/or branching after the sealing treatment.

• 한국화재소방학회논문지
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• 제23권3호
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• pp.17-22
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• 2009

에폭시 분체도료는 부스닥트, 및 전기기기에 절연재료로 광범위하게 사용되어 진다. 특히 Coating 절연 방식의 경우 전류에 의한 줄 열로 인해 전기화재 및 폭발의 점화 원인이 된다. 본 연구는 에폭시분체도료의 열화특성에 대해 절연파괴, 아크방전, 수명특성(V-t)을 중심으로 비교검토하고 이에 대한 기초데이터 확보 및 전기화재 원인인 절연특성에 대해 연구 하였다. 온도변화에 따른 절연특성은 시편 KS가 유리전이온도(Tg) 이전까지 $8{\sim}10%$ 정도의 감소로 안정적이었다. V-t 및 아크방전특성의 경우, 열화시편에서도 안정적 특성을 유지하였다. 열화에 의한 전기적특성의 경우 시편KS가 우수한 성능을 가지고 있다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.32-37
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• 2009

An energy loss through the window system occupies about 10 to 30 percent on energy consumption of the whole building. That is the reason, several elements for a building composition of window system are the weakest from the heat. Insulation performance increases for the reducing heat loss. Heat transfer through the window system that is reducing heat transfer through conduction, convection and radiation. Insulation performance reinforcement methods classify improving heat specific quality of window system and improving efficiency of whole window system. The most application method among each methods is reducing emission ratio of the window system(Low-E glass), increasing a number of glazing(multiple window) and a method of vacuuming between glazing and glazing. Therefore this study is investigated a sort of glazing and specific character, U-value calculation with changing glazing thickness and calculation of temperature distribution and U-value with a glazing charging gas kind from double glazing. For a conclusion, an aspect of U-value figure at the smallest value case of vacuum glazing with Low-E coating. That means insulation efficiency is the best advantage during a building plan selecting vacuum glazing with Low-E coating for a energy saving aspect. In this way, U-value become different the number of glazing, coating whether or not and selecting injection gas. Therefore selecting of glazing is very important after due consideration by a characteristic and use of building and consideration of strong point and weak point.

• 한국정밀공학회지
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• 제26권4호
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• pp.114-119
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• 2009

In this research, heat-acupuncture needle was coated with $Al_2O_3$ by applying a plasma spray coating method to prevent a skin burn. $Al_2O_3$, which is one of the representative bioceramics, does not have an influence on the chemical change in the body system. The ceramic coating thickness was about $100{\mu}m$. The experiments of heat conduction were performed for uncoated needle and coated needle. The results showed that the surface temperature of needle decreased as the needle was coated with $Al_2O_3$. The surface temperature of uncoated needle was about $48^{\circ}C$, while that of needle coated with $Al_2O_3$ was about $39^{\circ}C$.

• 한국재료학회지
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• 제27권9호
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• pp.471-476
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• 2017

In order to improve the high temperature oxidation resistance and lifespan of mat type porous carbon insulation, SiC was coated on carbon insulation by solution coating using polycarbosilane solution, curing in an oxidizing atmosphere at $200^{\circ}C$, and pyrolysis at temperatures up to $1200^{\circ}C$. The SiOC phase formed during the pyrolysis process was converted into SiC crystals as the heat treatment temperature increased, and a SiC coating with a thickness of 10-15 nm was formed at $1600^{\circ}C$. The SiC coated specimen showed a weight reduction of 8.6 % when it was kept in an atmospheric environment of $700^{\circ}C$ for 1 hour. On the other hand, the thermal conductivity was 0.17 W/mK, and no difference between states before and after coating was observed at all.

• 한국자기학회지
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• 제25권3호
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• pp.67-73
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• 2015

본 연구는 철기(Fe based) $Fe_{73.5}Si_{13.5}B_9Nb_3Cu_1$ 나노결정 합금의 분말코어(powder core)의 연자기적 특성 향상을 위한 기초연구로서, 절연 코팅제의 첨가량 및 분말입도에 따른 투자율, 코어손실 및 DC 바이어스 특성을 주로 조사하였다. 우선 합금조성을 PFC 장치를 이용하여 비정질 합금리본을 제조한 후, 열처리, 미분쇄 및 분급하여 얻어진 합금분말에 절연 코팅제(PEI)의 첨가량을 0.5, 1.0, 2.0, 2.5 wt%로 변화시켜 $16ton/cm^2$으로 압축성형 및 결정화 열처리하여 제조한 토로이달 나노결정 분말코어($OD12.7mm{\times}ID7.62mm{\times}H4.75mm$)는 절연 코팅제 함량이 증가할수록 투자율은 감소하였지만, 코어손실 및 DC 바이어스 특성은 향상됨을 확인하였다. 이러한 이유는 합금분말 절연 코팅제 첨가량이 증가할수록 비정질 합금분말 입자가 적어져 분말코어의 성형밀도가 낮아지기 때문으로 추정되었으며, 절연 코팅제의 함량은 1 wt%가 가장 적합한 것으로 판단되었다. 또한 절연 코팅제 함량을 1 wt%로 고정하고, 합금분말의 입도에 따라 제조한 분말코어의 경우, 실효투자율 및 코어손실은 입도가 클수록 우수하였지만, DC 바이어스 특성은 인가자장이 증가함에 따라 더욱 나빠짐을 확인하였다. 그 이유는 합금분말 표면의 코팅층 두께 차이에 의한 절연효과, 잔류기공 혹은 분말코어의 성형밀도 차이 등에 기인하는 것으로 추정되었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.35-36
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• 2023

Safety management of steel frame members is a very important part to maintain safety and function. However, precise inspection is not possible for steel frame members due to finishing materials and insulation materials, leading to poor inspection. For steel members, an insulating spray coating method is used for high thermal conductivity. The insulation spray method is not only uneconomical, but also has the disadvantage of spoiling the aesthetics. In addition, VOCs are released from paints used in spraying, so a solution is needed. In this study, heating paint was used to improve the disadvantages of the insulation spray coating method and the high thermal conductivity of steel frame members. In addition to this, in order to reduce VOCs generated from the paint, active clay was added to produce a functional exothermic paint, and then the experiment was conducted. As the amount of activated clay increased, the film thickness increased, and the VOCs emission and thermal conductivity decreased.

• Korean Chemical Engineering Research
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• 제50권4호
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• pp.621-626
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• 2012

본 연구에서는 마이크로 기공의 중공구를 유기 고분자 수지와 복합화한 유/무기 하이브리드 물질을 제조하여 우수한 단열 성능을 갖는 코팅유리를 개발하고자 하였다. 유기 고분자 물질로는 투명성과 접착성이 우수한 6관능기의 우레탄 아크릴레이트(UP118), 3관능기의 trimethylolpropane triacrylate (TMPTA), 2관능기의 1,6-hexanediol diacrylate (HDDA), 광 개시제(Irgacure184) 등으로 구성된 자외선 경화형 수지를 사용하였다. 유리 및 실리카 중공구를 고분자 수지에 각각 10~40 vol%까지 첨가하여 얻어진 코팅 졸을 투명유리에 바(bar)코팅 방식으로 박막을 형성시킨 후 자외선 경화를 통해 최종 코팅유리를 제조하였다. 마이크로 중공구의 종류 및 함량이 제조된 코팅유리의 광 투과율, 열전도도, 접착성 및 표면 경도에 미치는 영향을 조사하였다. 복합물 코팅유리는 중공구가 과량 첨가되어도 우수한 접착성(5B)을 유지하였으며, 단열 성능은 각 중공구가 20 vol%만 함유되어도 뚜렷하게 향상된 결과를 나타냈다. 또한 실리카 중공구(SP)를 단열 재료로 사용하였을 경우 광 투과율 80 %의 투명 코팅유리를 얻을 수 있었다.

• 한국초전도ㆍ저온공학회논문지
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• 제12권3호
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• pp.21-24
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• 2010

A cryogenic insulation technique for a high voltage and a large current capacity of a conductor are now two big issues in a field of recent R&D projects of superconducting power devices, especially a superconducting power transformer. For the large rated currents of the power transformer, it is well known that lots of 2nd generation superconducting conductor, so called coated conductor, should be stacked together with transpositions in order to get an even distributions of the currents. We had come up with an idea of a CTCC (Continuously Transposed Coated Conductor) as a conductor for a large power superconducting transformer, and keep trying to verify the usefulness of the conductor. As one of the efforts of verifying, we prepared and tested a sample CTCC with insulations for high voltage, which includes the epoxy coating and Nomex$^{(R)}$ wrapping. This paper contains the insulation process and dielectric breakdown test results. We expect the results obtained from this experiment to improve an insulation technique for high voltages in various cryogenic environments[1,2].

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.276-276
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• 2010

본 논문에서는 나노하이브리드 방법으로 제조된 변성 폴리이드계 나노하이브리드 절연코팅의 표면 굴곡특성을 비교 연구하였다. CS로 나노하이브리드화된 수지의 코팅표면의 표면거칠기를 AFM 으로 분석하여 그 변화를 비교하였다. CS로 처리된 나노하이브리드 코팅면의 경우 기초수지의 코팅면과 비교하여 기저재료와 상관없이 표면 거칠기는 현저히 줄어드는 경향을 나타내었다. 이는 20nm 이하의 균일한 CS입자가 균일하게 분산되어 수지 내에 자리하므로 기저물질의 거칠기를 보완하는 역할을 하기 때문으로 분석된다.