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Zirconium diboride (ZrB2) is the material suitable for high performance
applications. It has high melting point and high hardness value. On the other hand, recently,
mechanical activation and mechanical milling have been extensively used for synthesis of
advanced materials. In this present research, nanocrystalline ZrB2 was produced using
mixtures of zirconium dioxide, boric acid and pure magnesium as raw materials via
mechanochemical process. The phase transformation and structural evolution characterization
during process were utilized by X-ray diffractometry (XRD), scanning electron microscopy
(SEM) and transmission electron microscopy (TEM) techniques. A thermodynamic appraisal
showed that the reaction between ZrO2, H3BO3 and Mg is highly exothermic and should be
self-sustaining. XRD analyses exhibited that the nanocrystalline ZrB2 was formed after 60 h
milling time. The results indicate that increasing milling time up to 40 h had no significant
effect other than refining the crystallite size.
Keywords: mechanochemical; nanocrystalline; transmission electron microscopy; Zirconium diboride; Zirconium dioxride |
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