Synthesis and characterization of nano-structured TiB2 processed by milling assisted SHS route

TiB2 was synthesized via milling assisted self-propagating high-temperature synthesis (SHS) route using TiO2, H3BO3 and Mg powders as starting materials. The milling products were compacted and subjected to a hot filament on their top to initiate SHS. Effects of the milling time and addition of NaCl as a process diluent on the phase composition and morphology of the products were investigated. X-ray diffraction analysis indicated the formation of nano-crystalline TiB2 with mean crystallite size of 31 nm after acid leaching process at room temperature. Addition of 2 mol of NaCl in the same sample decreases the mean crystallite size to 27 nm. SEM and TEM micrographs showed that the mean particle size of TiB2 decreased from 200 nm in the un-milled sample to about 50 nm in the 5-hour mechanically activated (MA) sample.