• 제목/요약/키워드: material processing

검색결과 3,294건 처리시간 0.045초

용액 플라즈마 공정을 이용하여 제조된 금 나노유체의 특성평가 (Synthesis and Characterization of Glold Nanofluid Prepared by the Solution Plasma Processing)

  • 허용강;이상율
    • 한국분말재료학회지
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    • 제17권4호
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    • pp.342-346
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    • 2010
  • In the present work, water-based gold nanofluids were synthesized by the solution plasma processing (SPP). The size distribution and the shape of gold nanoparticles in the nanofluids were investigated using high resolution transmission electron microscopy (HR-TEM). The dispersion stability of gold nanofluids was characterized using zeta potential, as well. The thermal properties of gold nanofluids were measured by utilizing lambda measurement device. Nanofluids containing nanoparticles with $64.0{\pm}42.1\;nm{\sim}18.10{\pm}5.0\;nm$ in diameter were successfully synthesized. As diameter of nanoparticles decreased, dispersion stability of nanofluids increased and the enhanced ratio of thermal conductivity increased. The nanofluid with nanoparticles of $18.10\;{\pm}\;5.0\;nm$ in diameter showed approximately 3% improvement in thermal conductivity measurement and this could be due to the enhanced Brownian movement.

박판성형 공정에서의 불량 예측에 관한 연구 (A Study of prediction problem to Sheet metal forming processing)

  • 고형훈;이찬호;문원섭;박영근;정동원
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2005년도 추계학술대회 논문집
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    • pp.398-401
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    • 2005
  • The characteristic of sheet metal process is the few loss of material during process, the short processing time and the excellent price and strength. Such press-forming process are the used machine ability and the characteristic, used material, the accuracy of the part which becomes processing and side condition of a process are considered and the designed. The purpose of this study is apply efficiently sheet metal forming processing by 3D formation-analyzed program simulations in the site. By a study, forming process was simulation to drawing and trimming and cam process using static-implicit method software. By making apply this to an industrial site the productivity improvement and cost reduction etc. effect able was predicted.

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Bi 고온 초전도 박막의 부착 공정 (Sticking processing of Bi high $T_c$ superconducting thin films)

  • 천민우;김태곤;박용필
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 춘계학술대회 논문집
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    • pp.94-97
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    • 2005
  • Bismuth high Tc superconducting thin films are fabricated via a co-deposition process by an ion beam sputtering with an ultra low growth rate, and sticking processing of the respective elements are evaluated. The sticking processing of bismuth element in bismuth high Tc superconducting thin film formation was observed to show a unique temperature dependence; it was almost a constant value of 0.49 below about $730^{\circ}C$ and decreased linearly over about $730^{\circ}C$. This temperature dependence can be elucidated from the evaporation and sublimation rates of bismuth oxide, $Bi_2O_3$, from the film surface. It is considered that the liquid phase of the bismuth oxide plays an important role in the bismuth phase formation in the co-deposition process.

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박판을 이용한 Z-굽힘 가공의 전개 길이에 관한 연구 (A study on the unfolding length of Z-bending machining using thin plate)

  • 박용순;최계광
    • Design & Manufacturing
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    • 제15권3호
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    • pp.19-25
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    • 2021
  • The bending process of a press die is to bend a flat blank to the required angle. There are V-bending, U-bending, Z-bending, O-bending etc. for bending processing, and the basic principle of calculating the unfolding length of die processing is used as the neutral plane length. Since the constant of the length value of the neutral surface is different depending on the type of bending, it is impossible to accurately calculate it. In particular, Z-bending processing is performed twice, and it is set on the upper and lower surfaces of the blank, and bending processing occurs at the same time as the upward and downward bending, and the elongation of the material occurs and the material increases. It is not possible to check with the calculated value, and it occurs in many cases where the mold is modified after start-up. This study aims to minimize die modification by developing a formula to calculate the development length of Z-bend.

공구강의 내 마모성을 높여주는 레이저 클래딩 기술동향 (Trend of Laser Cladding Technology in Material Processing)

  • 길상철;김환태;김상우
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2008년도 추계학술대회 논문집
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    • pp.321-324
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    • 2008
  • The increasing interest in the surface modification by the laser cladding technology in the material processing is placing stringent demands on the manufacturing techniques and performance requirements, and the manufacture employs the high quality and efficiency laser cladding technology. This paper covers recent technical trends of laser cladding technology including the COMPENDEX DB analysis.

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PTA 오버레이 공정을 이용한 산업설비부품의 표면경화기술 (The Hardfacing Technology by PTA Overlaying Process)

  • 길상철;김환태;김상우
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2009년도 추계학술대회 논문집
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    • pp.358-361
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    • 2009
  • The increasing interest in the surface modification technology by the plasma transferred arc overlaying process in the material processing is placing stringent demands on the manufacturing techniques and performance requirements, and the manufacture employs the high quality and efficiency plasma transferred arc overlaying technology. This paper covers recent technical trends of plasma transferred arc overlaying technology including the COMPENDEX DB analysis.

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