• Title/Summary/Keyword: insulating coating

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Magnetic properties of Fe-based amorphous ribbon insulated by sol-gel process (졸-겔 법에 의해 절연코팅된 철계 비정질 리본의 자기특성)

  • 송재성;김병걸;정순종;김현식ㅂ;황시돌
    • Electrical & Electronic Materials
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    • v.9 no.2
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    • pp.159-164
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    • 1996
  • The development of an insulated coating which can be used for amorphous alloys is extremely important from the practical point of view. This importance may be enhanced by the influence of the coating on the magnetic properties. The purpose of this study is to show how new developed insulating coating materials and method influence the magnetic properties of amorphous Fe/sub 87/Zr/sub 7/B/sub 5/Ag/sub 1/(at%) ribbon.

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A Syudy on the High Temprerties of the 5Layer Functionally Gradient Thermal Barrier Coating (5층열장벽 피막의 고온 물성에 관한연구)

  • Han, J. C.;Jung, C.;Song, Y. S.;Yoon, J. K.;Lo, B. H.;Lee, K. H.
    • Journal of the Korean institute of surface engineering
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    • v.31 no.1
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    • pp.12-23
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    • 1998
  • The Thermal Barrier Coating(TBC) has been used to improve the heat barrier and tribological properties of the aircraft engine and the automobile engine in high temperature. Especially, the high temperature tribological propertied of the cylinder haed and the piston crown of diesel engine was emphasized. Therefore, the purpose of this work was to evaluate the microstructure, tribological propeer in high tempearmal shock resistance and bonding strength of five layer functionally gradient TBC for the applications. The five layerwere composed with 100% ceramic insulating later, 75(ceramic):25 (metal) layer, 50:50 layer, 25:75 layer and 100% metal bonding layer to redude the thermal stress. the YSL and MSL poweders were the insulation ceramics powers. The NiCrAly, Inconel625 and SUS powders were the bonding and mixingg powders for plasma spray process. According to the result of high temperature wear test, the wera resistance of YSZ/NiCrAlY siytem was most out standing at 600 and $800^{\circ}C$. At $400^{\circ}C$, the wear resistance of YSZ/Inconel system was better than others. Wear volume at other temperature because of the low temperature degration of zirconia. The thermal shock mechanism of 5 later is the vertical crack gegration in insulating layer. this means that the initial cracks were generated in the top layer, and then developed into the composite layers during thermal shock test. Finally, these cracks werereached to the interface of coating and substrate and also, these vertioal cracks join with the horizontal cracks of the each layers. The bonding strength of YSZ/NiCrAlY and YSZ/Inconel 5 layer system is better than other 5layer systems. The theramal shock resistance of thermal barrier coating s with 5 layer system is better than that of 3 layers and 2 layers.

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Study on Electrical Properties of Ceramic Coated Al Bus Bar (세라믹 코팅 Al 부스바의 전기적 특성 연구)

  • Baek, Seung-Myeong;Kwak, Min-Hwan;Kwag, Dong-Soon
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.66 no.11
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    • pp.1647-1650
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    • 2017
  • Bus bars are used in place of cables because they can carry more electrical energy with the same volume of conductors. This paper deals with the electrical properties of ceramic coating material for busbars. A ceramic coated samples were prepared for the electrical properties test. There are two types of samples. One is a sample without degradation, and the other is a sample degraded for 30 days. Four electrical properties tests were carried out in accordance with domestic standards. Four electrical characteristics tests are AC dielectric breakdown, V-t, lighting impulse dielectric breakdown, and discharge arc. Both samples showed excellent electrical properties, and the ceramic coating material is very good insulating materials for bus bar.

Fabrication of Organic Thin-Film Transistor Using Vapor Deposition Polymerization Method (Vapor Deposition Polymerization 방법을 이용한 유기 박막 트렌지스터의 제작)

  • 표상우;김준호;김정수;심재훈;김영관
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07a
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    • pp.190-193
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    • 2002
  • The processing technology of organic thin-film transistors (Ons) performances have improved fur the last decade. Gate insulator layer has generally used inorganic layer, such as silicon oxide which has properties of a low electrical conductivity and a high breakdown field. However, inorganic insulating layers, which are formed at high temperature, may affect other layers termed on a substrate through preceding processes. On the other hand, organic insulating layers, which are formed at low temperature, dose not affect pre-process. Known wet-processing methods for fabricating organic insulating layers include a spin coating, dipping and Langmuir-Blodgett film processes. In this paper, we propose the new dry-processing method of organic gate dielectric film in field-effect transistors. Vapor deposition polymerization (VDP) that is mainly used to the conducting polymers is introduced to form the gate dielectric. This method is appropriate to mass production in various end-user applications, for example, flat panel displays, because it has the advantages of shadow mask patterning and in-situ dry process with flexible low-cost large area displays. Also we fabricated four by four active pixels with all-organic thin-film transistors and phosphorescent organic light emitting devices.

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Biological Applications of Helium Ion Microscopy

  • Kim, Ki Woo
    • Applied Microscopy
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    • v.43 no.1
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    • pp.9-13
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    • 2013
  • The helium ion microscope (HIM) has recently emerged as a novel tool for imaging and analysis. Based on a bright ion source and small probe, the HIM offers advantages over the conventional field emission scanning electron microscope. The key features of the HIM include (1) high resolution (ca. 0.25 nm), (2) great surface sensitivity, (3) great contrast, (4) large depth-of-field, (5) efficient charge control, (6) reduced specimen damage, and (7) nanomachining capability. Due to the charge neutralization by flood electron beam, there is no need for conductive metal coating for the observation of insulating biological specimens by HIM. There is growing evidence that the HIM has substantial potential for high-resolution imaging of uncoated insulating biological specimens at the nanoscale.

Biological applications of the NanoSuit for electron imaging and X-microanalysis of insulating specimens

  • Ki Woo Kim
    • Applied Microscopy
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    • v.52
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    • pp.4.1-4.11
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    • 2022
  • Field emission scanning electron microscopy (FESEM) is an essential tool for observing surface details of specimens in a high vacuum. A series of specimen procedures precludes the observations of living organisms, resulting in artifacts. To overcome these problems, Takahiko Hariyama and his colleagues proposed the concept of the "nanosuit" later referred to as "NanoSuit", describing a thin polymer layer placed on organisms to protect them in a high vacuum in 2013. The NanoSuit is formed rapidly by (i) electron beam irradiation, (ii) plasma irradiation, (iii) Tween 20 solution immersion, and (iv) surface shield enhancer (SSE) solution immersion. Without chemical fixation and metal coating, the NanoSuit-formed specimens allowed structural preservation and accurate element detection of insulating, wet specimens at high spatial resolution. NanoSuit-formed larvae were able to resume normal growth following FESEM observation. The method has been employed to observe unfixed and uncoated bacteria, multicellular organisms, and paraffin sections. These results suggest that the NanoSuit can be applied to prolong life in vacuo and overcome the limit of dead imaging of electron microscopy.

Fabrication and Characterization of High Temperature Electrostatic Chucks

  • Bang, Jae-Cheol
    • The Korean Journal of Ceramics
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    • v.5 no.1
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    • pp.87-90
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    • 1999
  • It was suggested that tape casting method can be used to fabricate high-temperature electrostatic chucks(HTESC) based on a metal substrate coated with a glass-ceramic insulating layer. The adhesion of the coating was excellent such that it was able to withstand temperature cycling to over $300^{\circ}C$ without spalling. The electrostatic clamping pressure reached a very high value of about 9 torr at 600V and generally followed the theoretical voltage-squared curve. Based on these results, we believe that we successfully developed a viable technique for manufacturing low cost HTESC.

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