• Title/Summary/Keyword: electrical explosion

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Nanoscale Metal Powders Production by Electrical Explosion of Wire (전기선폭발법에 의한 나노금속분말의 제조)

  • 권영순;김흥회;이창규;임근희;박상하;정순호;김지순
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2003.03a
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    • pp.17-17
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    • 2003
  • 선폭법[전기선 폭발 법, Electrical Explosion of wire(EEW)]은 $10^{10A}$$m^2$ 이상의 고밀도 전류를 금속와이어에 인가하여 순간적으로 폭발시키는 기술로서 고밀도 대 전류가 금속와이어를 통과할 때, 저항발열에 의해 와이어가 미세한 입자나 금속증기 형태로 폭발하는 현상을 이용하여 나노분말을 합성하는 방법으로 나노 금속분말 뿐만 아니라 분위기 제어에 의한 산화물, 질화물, 탄화물 및 합금분말 둥 다양한 분말을 제조할 수 있는 장점이 있다. 또한 다른 제조법에 비해 양산화에 가장 근접한 기술로 알려져 있으며, 러시아가 세계적 기술수준으로 가장 앞선 것으로 알려져 있으며, 미국, 독일 및 일본 둥에서 1995년 이후 선폭 기술을 이용하여 나노분말 제조를 산업화하였다.다.

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A Study for Development and Characteristics of Electrostatic Eliminator for Charged Particles (대전된 분체의 정전기제거장치 개발 및 특성에 관한 연구)

  • Jung, Yong-Chul;Kim, Joon-Sam;Lee, Dong-Hoon
    • Journal of the Korean Society of Safety
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    • v.21 no.3 s.75
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    • pp.22-30
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    • 2006
  • On this study, we developed the electrostatic eliminator for charged particles in manufacturing process. The characteristics of the electrostatic eliminator were investigated, which is two kinds. The first one is Electrical Corona Discharged Type Ionizer. The second one is Photo Ionizer in using soft X-ray. From the experiment, we have obtained the following results. In case of Electrical Corona Discharged Ionizer, neutralization efficiency of charged particles were approximately saturated to 98% over 6.0kV, but as it is non-explosion proof, can not be used in flammable particle treatment process. While in case of photo Ionizer in using soft X-Ray, neutralization efficiency of charged particles were approximately 95%, and more its structure is explosion proof, could be used in flammable particle treatment process.

Fabrication of Fecralloy Foil Coated by Fecralloy Nanoparticles Using Electrospray Processing (정전 분무 공정을 이용한 Fecralloy 나노 입자가 코팅된 Fecralloy Foil의 제조)

  • Yun, Jung-Yeul;Yang, Sang-Sun;Koo, Hye-Young;Lee, Hye-Moon
    • Journal of Powder Materials
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    • v.18 no.6
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    • pp.526-531
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    • 2011
  • Fecralloy is the promising materials for high temperature exhaust filtering system due to the excellent its oxidation resistance property. In this research, Fecralloy nanoparticles coated Fecralloy thin foil was prepared by a single nozzle electrospray system in order to increase surface area of Fecralloy foil. Fecralloy nanoparticles were fabricated by electrical wire explosion method in ethanol using Fecralloy wires as a source material. Electrospray modes with applied D.C voltages to Fecralloy colloidal solution were investigated to make a stable cone-jet mode. Coated layers with and without additional heat treatment were observed by FE-SEM (field emission-scanning electron microscope) and tape test for evaluating their adhesion to substrate were performed as well.

Mechanism and Characteristics of Nano-dispersed Powder by Pulsed Discharge Method

  • Kwon, Young-Soon;Ilyin, Alexander P.
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2003.10a
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    • pp.27-32
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    • 2003
  • The phenomenon of electrical explosion of conductors is considered in the context of the changes in the energy and structural states of the metal at the stages of energy delivery and relaxation of the primary products of EEC. It is shown that these changes are related to the forced interaction of an intense energy flux with matter and to the subsequent spontaneous relaxation processes. The characteristics of nano-sized metal powders are also discussed.

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Phase Transformation by the Oxidation of Air-passivated W and Mo Nanopowders Produced by an Electrical Explosion of Wires

  • Kwon, Young-Soon;Kim, Ji-Soon;A. Gromov, Alexander;Hong, Moon-Hee
    • Journal of Powder Materials
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    • v.11 no.2
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    • pp.130-136
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    • 2004
  • The passivation and oxidation process of tungsten and molybdenum narlopowders, produced by electrical explosion of wires was studied by means of FE-SEM, XPS. XRD, TEM, DIA-TGA and sire distribution analysis. In addition, the phase transformation of W and Mo nanopowders under oxidation in air was investigated. A chemical process is suggested for the oxidation of W and Mo nano-particles after a comprehensive testing of passivated and oxidized powders.

Preparation and Analysis of Cu Nanopowder by Wire Explosion in Distilled Water (증류수 중 전기폭발에 의한 Cu 나노분말 제조 및 분석)

  • Cho, Chu-Hyun;Jin, Yun-Sik;Kang, Chung-Il;Lee, Gyung-Ja;Rhee, Chang-Kyu
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.7
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    • pp.1272-1275
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    • 2010
  • The Cu powder was prepared in distilled water. It has a wide range of size distribution. The submicron-sized particles in the Cu powder were removed by using continuous type centrifugal separator. The average particle size after classification was approximately 50nm. The XRD analysis showed that pure Cu phase and oxide phase ($Cu_2O$)weremixedinthepowderpreparedbythismethod.

Characterization and Stability of Silver Nanoparticles in Aqueous Solutions

  • Bac, L.H.;Gu, W.H.;Kim, J.C.;Kim, B.K.;Kim, J.S.
    • Journal of Powder Materials
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    • v.19 no.1
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    • pp.55-59
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    • 2012
  • In this work, the silver nanoparticles have been synthesized by electrical explosion of wire in three liquid mediums: deionized water (DIW), polyvinylpyrrolidone (PVP) and sodium dodecyl benzene sulfonate (SDBS) solutions. Absorption in the UV-visible region of these suspensions was measured in the range of 300-800 nm. A surface plasmon peak was observed at ~400 nm in all suspensions in measured wavelength range. Particle size was analyzed by transmission electron microscope. It showed that the particles had nearly spherical shape in all samples. The average particle sizes prepared in DIW, PVP and SDBS solution were 37, 31 and 27 nm, respectively. Stability of the suspensions was estimated by multiple light scattering method. The presence of PVP and SDBS surfactants in the exploding medium resulted in enhanced stability of the silver suspensions.

A Study on the Optimal Flash-Point of WDF Production (유화유 생산의 적정 인화점에 관한 연구)

  • Lee, Jin;Kim, Hwaseong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.33 no.4
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    • pp.310-314
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    • 2020
  • Although waste oil derived fuel (WDF) production technology was developed under a government initiative ~10 years ago, it became stagnant owing to the small size of participating companies, residents' rejection of foul odor, and the nature of the technology for recycling waste that was avoided. However, this subject is under the spotlight again because of recent developments, such as garbage crisis. In particular, plastic is the most difficult waste to dispose of, with more than 4 million tons of plastic waste produced every year according to statistics from the Ministry of Environment. The most effective method for treating plastic waste is to produce WDF through low temperature thermal decomposition. The WDF includes several volatile ingredients that mostly limit the use of fuel for boilers, owing to safety concerns. In particular, flash point is legally stipulated because of secondary contamination in the distribution process and the risk of fire and explosion. It is required that external shipments (distribution) should be maintained in the range of at least 30~60℃ (excluding explosion prevention facilities) for diesel power generation. Therefore, this study seeks to find the flash point that is best suited to WDFs produced from plastic waste.

Development of ESS Based on VRFB-LFPB Hybrid Batteries (VRFB-LFPB 하이브리드 배터리 기반의 ESS 개발에 관한 연구)

  • Cheon, Young Sik;Park, Jin Soo;You, Jinho;Lee, Jin
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.31 no.1
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    • pp.61-67
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    • 2018
  • High-power lithium batteries are suitable for equipment with high power output needs, such as for ESS's initial start-up. However, their management cost is increased by the installation of air-conditioning to minimize the risk of explosion due to internal temperature rise and also by a restriction on the number of charge/discharge cycles. High-capacity flow batteries, on the other hand, have many advantages. They can be used for over 20 years due to their low management costs, resulting from no risk of explosion and a high number of charge/discharge cycles. In this paper, we propose an ESS based on hybrid batteries that uses a lithium iron phosphate battery (LiFePO) at the initial startup and a vanadium redox flow battery (VRFB) from the end of the transient period, with a bi-directional PCS to operate two batteries with different DC voltage levels and using an efficient energy management control algorithm.