• 제목/요약/키워드: Protective coatings

검색결과 146건 처리시간 0.025초

Al-hot Dipping Followed by High-Temperature Corrosion of Carbon Steels in Air and Ar-0.2%SO2 Gas

  • Abro, Muhammad Ali;Jung, Seung Boo;Lee, Dong Bok
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2015년도 춘계학술대회 논문집
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    • pp.128-129
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    • 2015
  • Al-rich coatings were prepared on hot rolled low carbon steel by hot dipping method in molten Al-bath to investigate the corrosion resistance with the possible outcomes and defects of aluminized coatings in air and $Ar-0.2%SO_2$ mixed gases. Coating microstructure was composed of an inner Al-Fe intermetallic layer and outer Al-rich layer. Aluminum oxidized preferentially to the thin, outer, protective ${\alpha}-Al_2O_3$ layer, without forming the nonprotective iron/sulfur-oxide layer after heating at $800^{\circ}C$ for 20 h, in both the gases and provided the resistance against corrosion.

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Al-hot Dipping Followed by High-Temperature Corrosion of Carbon Steels in Air and Ar-0.2%SO2 Gas

  • 김민정;;박상환;지권용
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2015년도 춘계학술대회 논문집
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    • pp.122-122
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    • 2015
  • Al-rich coatings were prepared on hot rolled low carbon steel by hot dipping method in molten Al-bath to investigate the corrosion resistance with the possible outcomes and defects of aluminized coatings in air and $Ar-0.2%SO_2$ mixed gases. Coating microstructure was composed of an inner Al-Fe intermetallic layer and outer Al-rich layer. Aluminum oxidized preferentially to the thin, outer, protective ${\alpha}-Al_2O_3$ layer, without forming the nonprotective iron/sulfur-oxide layer after heating at $800^{\circ}C$ for 20h, in both the gases and provided the resistance against corrosion.

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3성분계(Li/Na/K) 용해성 규산염을 이용한 방화피복재의 개발 (A Development of Fire Protective Coatings using Ternary(Li/Na/K) Soluble Silicate)

  • 이내우;김정훈
    • 한국안전학회지
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    • 제10권1호
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    • pp.28-34
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    • 1995
  • To improve fire proofing characteristics of protective coating using ternary soluble silicate from two component mixture, the method of reducing solubility, increasing intumescence and protection time have been studied. Intumescence and solubility of ternary silicate mixtures were dependent on many kinds of water release and the strength of cation cross-links between polysilicate particles. Especially the effect of additive, for example, corn starch was investigated. However the solubility of ternary mixture is decrease in order of Na$^{+}$ >K$^{+}$ >Li$^{+}$, and the magnitute of intumescence is increased $K^{+}$ >Na$^{+}$ >Li$^{+}$.}$ +/.

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방화피복재 개발을 위한 용해성 규산염의 수화특성에 관한 연구 (A Study of Hydration Characteristics on Soluble Silicate to Develop Fire Protective Coating)

  • 김정훈;이내우
    • 한국안전학회지
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    • 제11권1호
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    • pp.90-98
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    • 1996
  • In order to investigate the effects on intumescence to fire protective coatings, the characteristics of solubility, hygroscopic nature and X-ray diffration results on soluble silicate were determined. Solubility is depended on the mutual action of each silicate. In the result of hygroscopic characteristics by water absorption under several kinds of relative humidity, lithium silicate is more stable than sodium and potassium silicate over moistures. Eventhough free water is evaporated over $100^{\circ}C$ , physically adsorption water and ionic water are eliminated about $200^{\circ}C$, but evolution of structural water is expected to be emitted between 400~$600^{\circ}C$ range. Those are considered to be contributed intumescence on soluble silicate.

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알칼리 규산염 내화 피복제의 개발 (A Development of Fire Protective Coating Based on Soluble Alkali Silicate)

  • 이내우;김종래;김정훈
    • 한국안전학회지
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    • 제8권2호
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    • pp.30-38
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    • 1993
  • To increase fire proofing characteristics of protective coating based on soluble alkali silicate, silicate coatings were studied on thermal properties, IR spectroscopy, solubility and intumescence. Intumescence and solubility of the samples were dependent on the strength of cationic cross-links between polysilicate particles. The degree of intumescence and solubility decrease K-silicate > Na-silicate > Li-silicate in the order. Especially Si$_2$O$_{5}$ $^{-2}$ crystalline regions were found to exist in Potassium silicate sample. Mixture of two kinds of silicate, for example, Lithium silicate when added to sodium silicate or potassium silicate was find to significantly reduce efflorescence and increase water resistance. This appears to be a result of stronger crosslinking between polysilicate particles by the small lithium cation.

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Polymers and polymer-based composites in tribology

  • Sviridenok, A.I.
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1990년도 제11회 학술강연회초록집
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    • pp.1-6
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    • 1990
  • Metal-Polymer Research Institute of Bneloressian Academy of Sciences is taking an active part in research and developments in field of polymer materials and composites. Many of these materials are devoted to use as a construction materials for machine parts, protective and decorative coatings on metals, films preventing corrosion in packaging of electronic, machinery and other components. This list can be continued by mentioning polymer capsulation coating for fertilizers, polymer filters produced by extruding and transfer of melted fibers etc.

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표면도장재를 적용한 콘크리트의 해양 노출시험 (Field Exposure Test of the Concrete Treated by Protective Surface Coatings in Marine Environment)

  • 정해문;유환구;안태송
    • 콘크리트학회지
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    • 제14권3호
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    • pp.71-76
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    • 2002
  • 콘크리트는 거의 반영구적인 재료라고 인식되어져 왔으나, 최근들어 해양환경, 적설한랭지대, 도심과 같은 열악한 환경속에서 예상보다 빨리 조기열화 되는 현상이 널리 알려지면서 콘크리트 구조물의 구조적 성능뿐만 아니라, 장기적인 내구성에 대한 관심이 높아져 가고 있다. 실제로 여러 선진국에서 염해와 같은 열화환경의 피해를 받은 콘크리트 구조물이 예상공용년수 이전에 철거되거나. 개보수 비용이 초기 건설비용보다 더 많이 드는 예가 적지 않게 보고되면서, 적절한 내구성 유지대책 및 구조물의 장수명화를 위해 많은 연구와 노력이 진행되고 있다.(중략)

STUDY PROCESSES OF INTUMESCENCE IN FIRE-PROTECTING COATINGS

  • Efremov, V.L.;Paltseva, N.G.;Leiman, Z.A.
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.657-658
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    • 2005
  • Flame retard of polymers was studied for prevention from burning by various additives stimulated the char formation during heating and thermal degradation of polymer materials. Forming char have high porosity, low thermal conductivity and act as thermal shield for heat transmission from the flame to the polymer and. oxygen towards the polymer. The results showed that various additives may regulate the processes of intumecsence. The efficient fire protective intumescent char was result of processes of melting, gas evolution, cross-linking, carbonization etc.

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유리고분자의 용매전달특성 및 그 해석 (Solvent Transport Characteristics of Glassy Polymers and its Analysis)

  • 김덕준
    • 멤브레인
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    • 제8권1호
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    • pp.11-21
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    • 1998
  • The study on penetrant transport in glassy polymers has been actively pursued for decades because of its growing significance in polymer processing and related applications such as not only membranes, but corrosion protective coatings, microlithography, microelectronic fabrication, etc. In membranes application of polymeric materials, successful utilization requires understanding of how solvents penetrate, swell, and sometimes dissolve polymeric materials under various environmental conditions, as their permselecdve performance is significantly affected by it. The expose of polymer membranes to solvents may result in the structural failure due to mechanical softening, embrittlement or crazing.

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Vanadium-Boride코팅의 고온 내입자침식성 평가 (Evaluation of High Temperature Particle Erosion Resistance of Vanadium-Boride Coating)

  • 이의열;김종하;정세일;이선호;엄기원
    • Corrosion Science and Technology
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    • 제14권2호
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    • pp.76-84
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    • 2015
  • The components in ultra super critical (USC) steam turbine, which is under development for high efficient power generation, are encountering harsher solid particle erosion by iron oxide scales than ones in the existing steam turbines. Therefore, the currently used boride coating will not be able to hold effective protection from particle erosion in USC system and should be replaced by new particle erosion resistant coatings. One of the best protective coatings developed for USC steam turbine parts was found to be vanadium-boride (V-boride) coating which has a hardness of about 3000 HV, much higher than that of boride, 1600~2000 HV. In order to evaluate particle erosion resistance of the various coatings such as V-boride, boride and Cr-carbide coatings at high temperature, particle erosion test equipments were designed and manufactured. In addition, erosion particle velocity was simulated using FLUENT software based on semi-implicity method for pressure linked equations revised (SIMPLER). Based on experimental results of this work, the vanadium-boride coating was found to be superior to others and to be a candidate coating to replace the boride coating.