• 제목/요약/키워드: reactive processing

검색결과 276건 처리시간 0.024초

Crystallization Vitrification and Phase Separation

  • Kim, Sung-Chul
    • 유변학
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    • 제1권1호
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    • pp.12-19
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    • 1989
  • Polymer fluid flow and polymerization reaction occur simultaneously during the reactive polymer processing. The viscosity and physical properties change as thereaction proceeds and the crystallization and vitrifica-tion occur as the T,,,and the Tg of the polymerizing fluid exceeds the reaction temperature within the mold.

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반응소결법에 의해 제조된 Fe-Al합금 예비성형체의 특성에 미치는 제인자의 영향 (Effects of Several Factors on the Characteristics of Fe-Al Alloy Preform Manufactured by Reactive Sintering Process)

  • 주형곤;박성혁;주성민;최답천
    • 한국주조공학회지
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    • 제17권1호
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    • pp.58-66
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    • 1997
  • The main aim of the present study is to investigate the effects of several processing parameters on the characteristics of Fe-Al alloy preform manufactured by reactive sintering process. The processing parameters include preform composition of 25, 40, 50, 60 and 75at.%Al, compacting pressure of 10, 20 and $30kg/cm^2$, and mean Al particle size of 29, 66 and $187{\mu}m$. Mean Fe particle size was $39{\mu}m$. The density of preform processed under same compacting pressure was not affected by changing Al composition. The preform with Al compositions of 25, 40, 50 and 60at.% Al swelled after reactive sintering process, thus having lower density than the green compacts. The preform with Al compositions of 75at.%Al, however, shrinked after reactive sintering process, thus having higher density than the green compacts. Ignition temperature increased with increasing compacting pressure, and increased with increasing Al composition at the fixed compacting pressure. And adiabatic temperature decreased with increasing compacting pressure at the fixed Al composition, and increased with increasing Al composition at the fixed compacting pressure. The size of compound particles increased with increasing Al composition. Especially, The size of compound particles increased largely in the case of 75at.%Al. It was observed that 50at.%Al preform have three dimentional network structure having a homogeneous and fine decreasing Al particle size.

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DC Reactive Magnetron Sputtering법에 의한 Ti-Al-V-N 박막의 성장거동 (Growth behavior of Ti-Al-V-N Films Prepared by Dc Reactive Magnetron Sputtering)

  • 손용운;정인화;이영기
    • 한국재료학회지
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    • 제9권7호
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    • pp.688-694
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    • 1999
  • Ti-6Al-4V 합금을 타겟트로 사용하여 유리 기판위에 dc reactive magnetron sputtering법으로 $N_2$/(Ar+N_2)$ 비, 기전력 및 시간등의 여러 가지 증착 조건에서 Ti-6Al-4V-N 필름을 증착하였고, 각각의 증착 조건에 따른 결정구조 및 우선방위 거동은 X-선 회절장치를 사용하여 조사하였다. Ti-6Al-4V-N 필름은 본질적으로 fcc 결정구조의 $\delta$-TiN에 Al과 V이 결함으로서 고용된 변형된 형태의 $\delta$-TiN구조이고, TiN의 격자상수(4.240 )보다 작은 값을 나타내었는데, 이는 Ti(1.47 )에 비하여 상대적으로 원자반경이 작은 Al(1.43 )과 V (1.32 )이 Ti의 격자위치에 치환된 결과이다. 그리고 Ti-6Al-4V-N 필름은 $_N2$가스 분압이 감소됨에 따라 (111) 우선방위 성장거동을 하였을 뿐만아니라 증착시간의 증가에 따라 뚜렷한 (111) 우선방위 성장거동을 나타내었다. 그리고 증착속도 및 결정입도의 거동 또한 여러 가지 증착 조건에 크게 의존한다

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Recent Advances and Trends in Reactive Polyurethane Adhesives

  • Krebs, Michael
    • 접착 및 계면
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    • 제7권4호
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    • pp.53-59
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    • 2006
  • The paper highlights technical advances and introduces recent innovations such as smart curing laminating adhesives for flexible packaging with low migration rates of aromatic isocyanates and amines. Latent reactive one-part systems on the basis of surface deactivated solid isocyanates open up new dimensions for heat setting adhesives and waterborne PU dispersions. The new generation of Purmelt Micro Emission adhesives contains less than 0.1% of MDI monomer, thereby drastically reducing the emission of hazardous isocyanate vapors during processing and setting a significantly improved technical standard in occupational safety. Once again, polyurethane adhesives have demonstrated their unique ability to adapt to new process, product, safety and environmental requirements.

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Enhanced hybrid Robot Architecture applied a human being nervous system

  • Choi, Dong-Hee;Kim, Hong-Seok;Park, Hong-Seong
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.2342-2345
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    • 2005
  • Robot control system considers various requirements. Firstly, it needs adaptation for unpredictable and dynamic environment. Secondly, it needs way to make do not injurious action to human because live with a person. Thirdly, it needs processing about aim of robots. In this paper proposed that these requirements effective robot control architecture. Robot control architecture can divide Deliberative, Reactive, Hybrid. Recently, robot control architecture that come Deliberative and use hybrid architecture that apply advantage of Reactive architecture is studied much. Hybrid control purpose to combine the real-time response of Reactive with the rationality of Deliberative. Our purpose is enhancement of hybrid architecture that is studied in these days. Proposed architecture that applied human's nervous system can reduce relativity between each module of existent architecture and drive response speed guarantee and safe robot action.

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구조 인텐서티법을 이용한 에어컨 실외기의 제진재 적용 (Damping Patch Placement on Outdoor Unit of Air-conditioner by Using Structural Intensity Technique)

  • 김규식;진심원;정인화;이정우;강연준
    • 한국소음진동공학회논문집
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    • 제14권7호
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    • pp.577-585
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    • 2004
  • In this paper, reactive shearing structural intensity method is extended to damping patches placement on outer panels of outdoor unit of air-conditioner to reduce its structural borne noise. The structural intensity is calculated from the normal velocities of structures that are measured by using a laser scanning vibrometer, and $textsc{k}$-space (wave-number domain) signal processing is used to obtain the spatial derivatives in formulation of structural intensity. This method is applied to the outdoor unit of air-conditioner on shaker-exciting mode and operating mode. and then damping patches are placed over area of high reactive shearing structural intensity for reducing the radiated noise. Experimental results show the largest reduction of sound pressure level of an outdoor unit by appling small damping patches to optimal position.