Effect of synthesis on the purity and particle size of ZrB2 powder
In the present investigation, an attempt has been made to prepare ZrB2 powder by self-propagating high temperature synthesis (SHS) technique. The effect of synthesis on the purity and morphology of powder is investigated. A stoichiometric mixture of ZrO2, H3BO3 and Mg powder is synthesised...
Main Authors: | , , , |
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Format: | Article |
Language: | English |
Published: |
Technical Faculty, Bor
2016-01-01
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Series: | Journal of Mining and Metallurgy. Section B: Metallurgy |
Subjects: | |
Online Access: | http://www.doiserbia.nb.rs/img/doi/1450-5339/2016/1450-53391600008G.pdf |
Summary: | In the present investigation, an attempt has been made to prepare ZrB2 powder
by self-propagating high temperature synthesis (SHS) technique. The effect of
synthesis on the purity and morphology of powder is investigated. A
stoichiometric mixture of ZrO2, H3BO3 and Mg powder is synthesised in a
resistance heating tubular furnace with continuous flow of high pure argon
gas. The synthesis is also carried out with NaCl as a diluent. The MgO is
leached out from the as-synthsised powder. Phase analysis of powder is
performed by X-ray diffraction (XRD). Laser beam scattering technique is used
to measure the particle size distribution. The morphology of powder is
characterized by scanning and transmission electron microscopes. The XRD
results show the presence of significant amount of unreacted ZrO2 phase in
the product. The product is mixed with calculated amount of magnesium and
boric acid and the mixture is synthesised further. There is a significant
decrease of unreacted ZrO2 in the product after double synthesis. The SEM
images show the presence of agglomeration of fine particles, whereas the TEM
images show the decrease of particle size after double synthesis. To
understand the synthesis process, the individual synthesis of ZrO2-Mg and
H3BO3-Mg are also performed. |
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ISSN: | 1450-5339 2217-7175 |