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Title: Generation of nano aluminium powder through wire explosion process and its characterization

Abstract

The nano aluminium particles were produced in different ambience by the wire explosion process. The influence of pressure in the exploding wire chamber on the size of the particles was analyzed. Certain physico-chemical diagnostic studies, viz., wide angle X-ray diffraction (WAXD), thermo-gravimetric differential thermal analysis (TG-DTA) studies were carried out to characterize the produced nano aluminium powder. The compositions of the material were characterized through the energy dispersive analysis by X-ray (EDAX) results. The size of the particles was measured using transmission electron microscope (TEM) studies and particle size distribution analyses were carried out by adopting log-normal distribution. The mechanism of formation of nano powder by wire explosion technique was explained in detail.

Authors:
 [1];  [2];  [3]
  1. Department of Electrical Engineering, IIT Madras, Chennai-600 036 (India). E-mail: rsarathi@iitm.ac.in
  2. Department of Electrical Engineering, IIT Madras, Chennai-600 036 (India)
  3. Department of Aerospace Engineering, IIT Madras, Chennai-600 036 (India)
Publication Date:
OSTI Identifier:
21003529
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Characterization; Journal Volume: 58; Journal Issue: 2; Other Information: DOI: 10.1016/j.matchar.2006.04.014; PII: S1044-5803(06)00113-6; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM; DIFFERENTIAL THERMAL ANALYSIS; EXPLODING WIRES; EXPLOSIONS; PARTICLE SIZE; PLASMA; TRANSMISSION ELECTRON MICROSCOPY; X-RAY DIFFRACTION

Citation Formats

Sarathi, R., Sindhu, T.K., and Chakravarthy, S.R. Generation of nano aluminium powder through wire explosion process and its characterization. United States: N. p., 2007. Web. doi:10.1016/j.matchar.2006.04.014.
Sarathi, R., Sindhu, T.K., & Chakravarthy, S.R. Generation of nano aluminium powder through wire explosion process and its characterization. United States. doi:10.1016/j.matchar.2006.04.014.
Sarathi, R., Sindhu, T.K., and Chakravarthy, S.R. Thu . "Generation of nano aluminium powder through wire explosion process and its characterization". United States. doi:10.1016/j.matchar.2006.04.014.
@article{osti_21003529,
title = {Generation of nano aluminium powder through wire explosion process and its characterization},
author = {Sarathi, R. and Sindhu, T.K. and Chakravarthy, S.R.},
abstractNote = {The nano aluminium particles were produced in different ambience by the wire explosion process. The influence of pressure in the exploding wire chamber on the size of the particles was analyzed. Certain physico-chemical diagnostic studies, viz., wide angle X-ray diffraction (WAXD), thermo-gravimetric differential thermal analysis (TG-DTA) studies were carried out to characterize the produced nano aluminium powder. The compositions of the material were characterized through the energy dispersive analysis by X-ray (EDAX) results. The size of the particles was measured using transmission electron microscope (TEM) studies and particle size distribution analyses were carried out by adopting log-normal distribution. The mechanism of formation of nano powder by wire explosion technique was explained in detail.},
doi = {10.1016/j.matchar.2006.04.014},
journal = {Materials Characterization},
number = 2,
volume = 58,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
  • Nano tungsten oxide particles are produced by wire explosion process. It is realized that by exploding tungsten conductor in lower pressure of oxygen, unreacted phase of tungsten was present and it could be reduced by increasing the operating pressure and increasing the amount of energy deposited to the exploding conductor. It is realized that the nucleation rate of the particle could be high only at the point of maximum saturation ratio, irrespective of the pressure of the oxygen. The size of the critical nucleus formed is low when the saturation ratio and the nucleation rate are at maximum. The nanomore » metal oxide particle formation by wire explosion process allows one to conclude that the second stage annealing process has a major impact on the final grain size formed. The high speed camera photographs of wire explosion process were used to understand the dynamics of particle formation by wire explosion process. The Transmission Electron Microscopy (TEM) analysis indicates that the nano tungsten oxide (WO{sub 3}) particles are of spherical shape and the analysis of particle size indicates that it follows log normal distribution. - Graphical Abstract: Nano tungsten oxide (WO{sub 3}) particles are produced by wire explosion process. Theoretical analysis indicates that the size of the critical nucleus formed is low when the saturation ratio and the nucleation rate are at maximum. High speed camera photographs of wire explosion process were used to understand the dynamics of particles formed. Research Highlights: {yields}Lower particle size is possible with lower pressure. {yields}Particle size is increased with reduced energy ratio. {yields}Unreacted tungsten content reduces when oxygen pressure increases.« less
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  • Results are presented from experimental studies and numerical simulations of the effect of preliminary wire explosion on the parameters of X-ray emission generated during wire array Z-pinch implosion. The wire array implosion was driven by a current pulse with an amplitude of 0.5 MA and a rise time of 0.5 {mu}s, while the preliminary wire explosion was produced by a current pulse with an amplitude of 0.5-1 kA per wire, a rise time of 100 ns, and a full width at half maximum of {approx}200 ns. The experiments showed that the current prepulse significantly impaired the parameters of X-ray pulses.more » In particular, along with a decrease in the amplitude and an increase in the duration of the X-ray pulse, its spiky structure became more pronounced. The results of numerical simulations with the use of a one-dimensional radiative MHD code are in good agreement with the parameters of Z-pinch emission in experiments with and without a current prepulse.« less
  • An alloy with aluminium as its base element is heat treated to form a multitude of precipitate phases known from different classes of industrial alloys: Al–Cu(–Mg), Al–Mg–Si–Cu, and Al–Zn–Mg. Nanometer-sized needle-shaped particles define the starting point of the phase nucleation, after which there is a split in the precipitation sequence into six phases of highly diverse compositions and morphologies. There are several unique effects of phases from different alloy systems being present in the same host lattice, of which we concentrate on two: the replacement of Ag by Zn on the Ω interface and the formation of combined plates ofmore » the θ′ and C phases. Using atomically resolved scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy, we investigate the formation mechanisms, crystal structures and compositions of the precipitates. - Graphical abstract: Display Omitted - Highlights: • An aluminium alloy composition in-between the 2/6/7xxx systems was investigated. • Six different phases from the three systems coexist in an over-aged state. • All phases with 〈001〉{sub Al} coherencies can nucleate on 6xxx needle precipitates. • Modified theta′ and omega interfaces are observed.« less
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