Production of nanocrystalline TiB2powder through self-propagating high temperature synthesis (SHS) of TiO2-H3BO3-Mg mixture

Abstract

Nanocrystalline TiB2 powders are produced through self-propagating high temperature synthesis (SHS) technique by igniting the stoichiometric mixture of titanium oxide (TiO2), boric acid (H3BO3) and magnesium (Mg) powder. Different percentages of NaCl are added to the mixture as SHS diluent in order to control the particle size of the TiB2. The synthesised and purified powder is characterised by X-ray diffraction and electron microscopes respectively. The SEM images show the presence of agglomeration of fine spherical particles. The TEM images reveal the formation of nanocrystalline TiB2 particles. The particle size is found to decrease with the addition of NaCl. The TEMimagesreveal the presence of crystallographic defects in the powder. In order to find out the reaction mechanism of TiO2–H3BO3–Mg system, the synthesis of TiO2–Mg and H3BO3–Mg mixtures is performed in inert atmosphere and phase analysis of TiO2–Mg and H3BO3–Mg mixtures reveal the reaction mechanism.