Investigation of Phase Evolution of TiC-TiB2 Nanostructure Fabricated by MASHS (RESEARCH NOTE)

Nanocomposite of titanium diboride/titanium carbide was fabricated by combustion synthesis of mechanically milled reactant powders. The stoichiometric mixture of Ti and B4C as starting materials milled for 1, 3, 6 and 9 h. Milled powders pressed to form pellets then green compacts were placed in a tube furnace that preheated to 1100 oC in inert atmosphere (Ar).The samples were investigated by XRD and SEM analysis after different milling times and synthesis process. TiC and TiB2 were not formed during milling process. But analysis of synthesized samples showed TiC was the first formed phase and followed by TiB2, whereas other phases were not detected in the samples that pre- milled for 6 and 9 h. The increasing of milling time helped significantly to improve distribution of TiB2 in products. The crystallite size of TiB2 and TiC in the composite based on milled powder for 9 h calculated 46.2 nm and 34.6 nm respectively.