Synthesis of nano-sized titanium diboride in a melt of anhydrous sodium tetraborate

Abstract

X-ray powder diffraction, scanning electron microscopy, infrared spectroscopy, and elemental analysis were used to study the interaction of titanium powder with finely powdered boron of particle size 10-20 μm in Na 2 B 4 O 7 ionic melt, in the temperature range 973-1088 K, at the 5-10 h contact duration. The TiB 2 formation was shown to occur at the temperatures 1018 K or above, that is, at the borax melting temperature. According to the scanning electron microscopy, theTiB 2 powder consists of the 70-75 nm particles, and its coherent scattering region calculated from the XRD data amounts to 55 nm.

Low‐temperature preparation of titanium diboride fine powder via magnesiothermic reduction in molten salt

“…[1][2][3] Such a unique combination of excellent properties makes TiB 2 a promising candidate material for a variety of applications, for example, in impact resistant armors, cutting tools, high-temperature wear-resistant parts, electrodes in metal smelting cells, neutron absorbers, and electrocatalysts for renewable energy. 3,4 A number of techniques/methodologies have been investigated for TiB 2 preparation, including direct elemental reaction via self-propagating high-temperature synthesis (SHS), 5 high-energy ball milling (HEBM) 6 or in a sodium borate melt, 7 carbo/borothermic or borocarbide reduction, [8][9][10][11][12] metallothermic reduction via HEBM, [13][14][15] SHS 16 or volume combustion synthesis, 17 solvo/hydrothermal method, [18][19][20] molten salt electrolysis, 21 laser-induced vapor phase reaction, 22 and aluminum melt reaction. 23 Unfortunately, these techniques suffer from various disadvantages, for example, use of expensive raw materials (eg, elemental boron and titanium), requirement of specialty reaction vessels and high processing temperature and long processing time, and contamination from milling media due to prolonged milling.…”

Preparation of hafnium diboride nanopowders in an anhydrous Na2B4O7 ionic melt

“…As shown earlier [10][11][12], reactions between tita nium (zirconium) and boron powders in an anhydrous Na 2 B 4 O 7 ionic melt at a temperature of 800°C lead to the formation of TiB 2 and ZrB 2 nanopowders. It was of interest to investigate distinctive features of synthe sis in ionic melts with application to the preparation of HfB 2 nanopowders.…”

Nanostructured titanium, zirconium and hafnium diborides: the synthesis, properties, size effects and stability

“…The lattice constants of particles of TiB 2 and ZrB 2 nanopowders synthesized by different methods 24,40,41,43 slightly deviate from the tabulated (recommended) values (see Table 1). This can be due to the presence of impurities and defects originating from deformation (e.g., ball milling).…”