• 제목/요약/키워드: Corrosiveness

검색결과 39건 처리시간 0.029초

해수환경중 캐비테이션 침식 -부식 하에서의 응력부식균열거동(I) (Stress Corrosion Cracking Behavior under Cavitation Erosion-Corrosion in Sea Water-Part (I))

  • 안석환;임우조
    • 수산해양기술연구
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    • 제36권2호
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    • pp.132-138
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    • 2000
  • The effect of fluid flow on corrosion and erosion-corrosion of metal is a well-recognized phenomenon in pipelines and machinery equipment, and so on. Not only are fluid hydrodynamics important, but also the corrosiveness of the process or production stream affects the corrosion system. Recent research demonstrates that it is possible to erosion-corrosion(E/C) phenomena in terms of hydrodynamics, electrochemical corrosion kinetics and film growth/removal phenomena. Stress corrosion cracking behavior under cavitation erosion-corrosion of mild steel(SS41) was investigated of base metal and weldment under loaded stress. Main result obtained are as follows : 1) The cavitation erosion sensitivity of base metal affected weight loss is more susceptive than heat affected zone, 2) The corrosion sensitivity affected weight loss of welding heat cycle is less susceptive on stress corrosion under cavitation erosion-corrosion than stress corrosion.

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고분자 수지를 이용한 자동차 에어컨용 압축기의 씰에 관한 연구 (A Study on Compressor Seal for Automotive Air-conditioner using Polymer Resin)

  • 정태형;하영욱
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2002년도 춘계학술대회 논문집
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    • pp.22-27
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    • 2002
  • The existing compressor steel seal used in automotive air-conditioner has the problem of oil leakage and the deterioration in shielding performance, due to the abrasion and the corrosion of the material. A new type of polymer resin seal is studied in the research. The polymer resin seal has the characteristics of high anti-abrasiveness and anti-corrosiveness, which can overcome the deflects of the steel seal. In addition, the seal needs lower manufacturing cost and is appropriate to mass production, because it is made by the injection molding method requiring no mechanical processing. The profile generation program for seal mold has been developed using the gradient method, and the molding characteristics of the seal have analyzed through the flow analysis and the warpage analysis. The program has been verified by comparing the analysis results with the measured data of the test product. The research might be said to provide the basic method to produce the polymer resin seals with various types and dimensions.

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빔 에너지를 이용한 내 마모 및 내 부식성을 갖는 철망 가공 기술 (Wire netting processing technology with abrasion and corrosiveness by using Beam energy)

  • 정성찬;선경철;신영식;최정식;차인수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.1029_1030
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    • 2009
  • 본 논문에서는 빔 에너지를 이용하여 내 마모 및 내 부식성을 갖는 철망을 가공하여, 빔 에너지 조사 전과 후의 SEM 사진과 인장강도를 측정하여 비교, 분석 하였다. 전자빔으로 표면을 개질하기 전보다 후의 표면이 더 치밀해짐을 SEM사진을 통하여 볼 수 있었고, 인장강도를 측정 하여 개질 전과 후를 비교 하였는데, 인장강도와 관련된 탄성계수가 더 크게 나타나 전자빔 조사에 의한 샘플이 긴 수명을 갖는 요인이 분석되었다.

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친환경 제설제 개발 현황 (Current Status of Eco-Friendly Deicing Material Development)

  • 서호성;박병흥
    • 융복합기술연구소 논문집
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    • 제6권2호
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    • pp.25-28
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    • 2016
  • Recently, due to the climate change by global warming, the amount of snow has increased. The situations were demanded to use many snow removal materials. The snow removal materials that used in Korea were solid chloride deicing material. That is calcium chloride($CaCl_2$) and sodium chloride(NaCl). Solid chloride baesd snow removal materials have various property, for example good freezing point depression, deliquescence and economical solvents. However, there are problems such as water pollution, high corrosiveness and ecocide. For such reason, development of eco-friendly deicer was required obligatorily. This study investigated development situation of eco-friendly deicer materials.

고분자 수지를 이용한 자동차 에어컨용 압축기의 씰에 관한 연구 (A Study on Compressor Seal for Automotive Air-conditioner using Polymer Resin)

  • 정태형;하영욱
    • 한국공작기계학회논문집
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    • 제11권5호
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    • pp.81-87
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    • 2002
  • The existing compressor steel seal used in automotive air-conditioner has the problem of oil leakage and deterioration in shielding performance, due to the abrasion and corrosion of the material. A new type of polymer resin seal studied in this research has the characteristics of high anti-abrasiveness and anti-corrosiveness, which can oversome the defects of the steel seal. In addition, the seal needs lower manufacturing cost and is appropriate to mass production, because it is made by the injection molding method requiring no mechanical processing. The profile generation program for seal mold has been developed using the gradient method, and the molding characteristics of the seal have analyzed through the flow analysis and the warpage analysis. The program has been verified by comparing the analysis results with the measured data of the test product. The research might be said to provide the basic method to produce the polymer resin seals with various types and dimensions.

Fiber Reinforced Framework를 이용한 Implant 수복증례 (Implant Restorations Using Fiber Reinforced Framework)

  • 송호용;이양진;조리라
    • 대한심미치과학회지
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    • 제10권2호
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    • pp.21-30
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    • 2001
  • Fiber reinforced materials have favorable mechanical properties. Moreover, the strength to weight ratios of this material is superior to those of most alloys. Comparing to the metals, it showed many other advantages as well, including non-corrosiveness, translucency and easy repair characteristic. Since, it has the potential for the chair-side and laboratory fabrication, it is not surprising that fiber reinforced composites offer the potential for use in various applications in dentistry. To make the well-fitted restorations, Fiber reinforced composite (FRC) has been suggested as an alternative framework material for the implant supported fixed prosthesis. Two fixed partial denture fabrication procedures were tried. Vectris fiber was pressed to the EsthetiCone gold cylinder on the implant positioned cast. And then, Targis were added on it. In the other method, we used the customized component using UCLA abutment. The beads for retaining the Vectris fiber were added on the abutment. If careful laboratory and clinical techniques were done, these two techniques would fulfill the demands of the esthetics and strength.

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Anodic formation of TiO2 nanoporous structures at high temperature in a glycerol/phosphate electrolyte

  • 이기영
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2017년도 춘계학술대회 논문집
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    • pp.95.2-95.2
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    • 2017
  • Anodic TiO2 nanostructures have wide applications due to their various functional properties such as wide band-gap, chemical stability, and anti-corrosiveness. In order to enhance the properties, several approaches to fabricate TiO2 structures have been developed. Especially, TiO2 nanotube arrays prepared by anodization in a fluoride electrolyte show impressive properties for dye sensitized solar cells1 and photocatalyst. In this presentation, we introduce new types of TiO2 nanostructures beyond TiO2 nanotubes that are fabricated by anodization at high temperature in a glycerol/phosphate electrolyte. We show that depending on the anodization parameters different self-organized morphologies - of highly aligned, high aspect ratio oxide structures can be formed. Critical factor for growth and the use for dye sensitized solar cells and photocatalyst will be discussed.

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Fiber-Reinforcements of Composite Restorations

  • Cho, Kyung-Mo
    • 대한치과보존학회:학술대회논문집
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    • 대한치과보존학회 2001년도 춘계학술대회
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    • pp.258-258
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    • 2001
  • Fiber-reinforced materials have highly favorable mechanical properties. and their strength-to-weight ratios are superior to those of most alloys. When compared to metals they offer many other advantages as well. including non-corrosiveness. translucency. good bonding properties. and ease ofrepair. Fiber-reinforced materials can be categorized to pre-impregnated. impregnation required. dental laboratory products. chairside products and prefabricated posts. so it is not suprising that fiber-reinforced composites have potential for use in many applications in dentistry. Fiber-reinforced materials can be utilized in frameworks for crowns. anterior or posterior fixed prostheses. chairs ide tooth replacements. periodontal splints. customized posts. prefabricated posts. orthodontic retention. denture reinforcements and in implants dentistry. To realize the full potential of using fiber-reinforced composite restorations. it is essential that the clinician and laboratory technician understand concepts of tooth preparation and framework design. Also practitioner may appreciate the background information and other details about the materials themselves so that identify the rationale for their use in various clinical situations. select well-suited materials. and carry out related procedures. Understanding the material properties and take many attentions. fiber-reinforced materials will give more esthetic. more easy. more strong and more reliable restorations.ations.

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재생골재를 사용한 폴리머콘크리트 경계블록의 개발 연구 (A Study on the Development of Polymer Concrete Curbs Using Recycled Aggregate)

  • 최영준;박준철;윤요현;김상연;김화중
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2000년도 가을 학술발표회 논문집(II)
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    • pp.1127-1132
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    • 2000
  • The purpose of this study is to investigate the utilization of recycled fine aggregates as a material to apply to concrete curbs. This study also intends to improve the quality of recycling aggregates by adding an excellent polyester resin for the improvement of durability, anti-corrosiveness, and strength. The experimental mixing proportion was planned to acquire optimum workability and filling capability of resin mortar mixed with the recycled fine aggregate. The curbs products made for test have four type cross sections. Their flexible fracture load is 1,918~6,883kgf and their weight is 15.31~31.61kg.

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탄소강의 녹물저감에 대한 인산염부식억제제와 석회수 효과 연구 (The Effects of Polyphosphate Corrosion Inhibitor and Lime Water to Reduce Red Water for Carbon Steel)

  • 박영복;공성호
    • 상하수도학회지
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    • 제19권2호
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    • pp.228-237
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    • 2005
  • The main purpose of this study was to investigate the red water reducing effects of phosphate based inhibitor when it was applied to water distribution system. The effects of pH, alkalinity, calcium concentration in the reduction of the red water also studied. The most finished water in Korea showed relatively high corrosiveness and was required to introduce some types of corrosion reducing methods such as addition of alkalinity. The precipitation of $CaCO_3$ by addition of $Ca(OH)_2$ formed porous film on the surface of the carbon steel pipes and was displaced easily from the surface of the pipes; on the other hand, addition of zinc phosphate (ZOP) formed reliable film on the surface and reduced iron release and color. Although the main function of ZOP was to suppress the release of Pb and Cu, it also reduced iron concentration released from water distribution pipes.