• Journal of Powder Materials
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• v.11 no.1
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• pp.60-68
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• 2004

Pulsed wire evaporation (PWE) method is known as the promising production-technique for nanopowders. In this study, we developed and modified the previous single wire explosion equipment to the simultaneous two-wire explosion one for the fabrication of alloy or mixture of nano metallic powder. First of all, both the theoretical and empirical background of pulsed wire explosion of single wire were summarized, and compared with our experimental results for Cu and Al single wlre explosion. After then, the simultaneous wire evaporation equipment was designed, constructed, and tested. The current and voltage behavior were well matched between the calculated ones from the circuit equations, and the experimental results from simultaneous explosion of Cu and Al wire.

• Particle and aerosol research
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• v.6 no.1
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• pp.37-46
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• 2010

Cu nano-colloid was prepared by wire electric explosion process under de-mineralized water and anhydrous ethanol. To control the properties of Cu nano-colloid, experimental conditions such as diameter of Cu wire and applied voltage were changed. The optimal Cu nano-colloid was prepared when the 0.1mm diameter of Cu wire with the applied voltage of 2000 V was used. The shape of Cu particles in colloid was spherical and the XRD result revealed that the phase of Cu particles was cubic phase. About 20nm Cu nanoparticles with high crystallinity were successfully prepared using wire explosion process under anhydrous ethanol and they showed more than 100 hours dispersion stability.

• Journal of Powder Materials
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• v.14 no.1 s.60
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• pp.38-43
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• 2007

Cu-Zn alloy nano powders were fabricated by the electrical explosion of Zn-electroplated Cu wire along with commercial brass wire. The powders exploded from brass wire were composed mainly of ${\alpha},{\beta},\;and\;{\gamma}$ phases while those from electroplated wires contained additional Zn-rich phases as ${\varepsilon}$, and Zn. In case of Zn-elec-troplated Cu wire, the mixing time of the two components during explosion might not be long enough to solidify as the phases of lower Zn content. This along with the high vapor pressure of Zn appears to be the reason for the observed shift of explosion products towards the high-Zn phases in electroplated wire system.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 1999.10a
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• pp.8-8
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• 1999

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2057-2059
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• 2005

Silver nanosized powder have been synthesized using wire explosion technology. The discharge system of 10kw (10uF, 20kV, 0.5 shots/s) was set up for mass production of 300g/h. The high purity silver powder was collected and separated by cyclone and fabric filters.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.9
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• pp.452-455
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• 2006

The technology of wire explosion have been used to product nanopowders. A new concept was proposed to produce metallic nanosized powders, which is wire explosion in liquid media. We have exploded the Ag or Cu wires of diameter of O.3mm, 40mm long, in the de-ionized water or acetone, respectively. Electrical energy of 1.1kJ was stored in 10uF capacitor and released to the wires through a triggered spark gap switch. The process was observed by high-speed camera. Those images showed that the powders were generated by vapor condensation in the shell formed by shock wave in the water. The particles were directly dispersed into the water with collapse of the shell. The sizes of Ag and Cu nanopowders were evaluated to 35nm and 17nm, respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.1
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• pp.27-37
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• 1997

The aim of the present study is to investigate experimentally the mechanism of an exploding wire in water and also to observe the bubble motion induced by an exploding wire. The experiment of an exploding wire is carried out in a water tank. As a metallic wire, a tungsten wire of 0.2mm in diameter and 10mm in length is employed. The electric energy of 50-300J is fed to the wire from a capacitor of 100$\mu$F charged up to 1-2.5kV. The explosion is recorded by a CCD camera with the resolution of 1$\mu$sec. The explosion process of metallic wire is divided into three phases. Phase 1 : As the voltage is applied to the wire, the temperature increases due to Joule heating and the wire emits light. Phase 2 : Then the wire melts and the cylindrical plasma is formed between the electrodes. Up to this stage, strong light emission is observed. Phase 3 : The light emission goes out and a vapor bubble begins to grow spherically. The radius of a bubble oscillates in time, but the amplitude of oscillation diminishes in several cycles.

• Journal of Powder Materials
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• v.23 no.6
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• pp.409-413
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• 2016

Electrical wire explosion in liquid media is a promising method for producing metallic nanopowders. It is possible to obtain high-purity metallic nanoparticles and uniform-sized nanopowder with excellent dispersion stability using this electrical wire explosion method. In this study, Ni-Fe alloy nanopowders with core-shell structures are fabricated via the electrical explosion of Ni-Fe alloy wires 0.1 mm in diameter and 20 mm in length in de-ionized water. The size and shape of the powders are investigated by field-emission scanning electron microscopy, transmission electron microscopy, and laser particle size analysis. Phase analysis and grain size determination are conducted by X-ray diffraction. The result indicate that a core-shell structured Ni-Fe nanopowder is synthesized with an average particle size of approximately 28 nm, and nanosized Ni core particles are encapsulated by an Fe nanolayer.

• Particle and aerosol research
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• v.8 no.2
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• pp.83-88
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• 2012

The electrical wire explosion process in liquid media is promising for nano-sized metal and/or alloy particles. The hybrid Pt/Fe-Cr-Al and Pt/Ni-Cr-Fe nanoparticles for exhaust emission control system are synthesized by electrical wire explosion process in liquid media. The alloy powders have spherical shape and nanometer size. According to the wire component, while Pt/Fe-Cr-Al nanoparticles are shown the well dispersed Pt on the Fe-Cr-Al core particle, Pt/Ni-Cr-Fe nanoparticles are shown the partially separated Pt on the Ni-Cr-Fe core particle. Morphologies and component of two kinds of hybrid nano catalyst particles were characterized by transmission electron microscope and energy dispersive X-ray spectroscopy analysis.

• Journal of Powder Materials
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• v.13 no.3 s.56
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• pp.187-191
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• 2006

Al-Cu alloy nano powders were produced by the electrical explosion of Cu-plated Al wires. The composition and phase of the alloy could be controlled by varying the thickness of Cu deposit on Al wire. When the Cu layer was thin, Al solid solution and $CuAl_2$ were the major phases. As the Cu layer becomes thicker, Al diminished while $Al_4Cu_9$ phase prevailed instead. The average particle size of Al-Cu nano powders became slightly smaller from 63 nm to 44 nm as Cu layer becomes thicker. The oxygen content of Al-Cu powder decreased linearly with Cu content. It is well demonstrated that the electrodeposition combined with wire explosion could be simple and economical means to prepare variety of alloy and intermetallic nano powders.