Reaction synthesis of TiC–TiB2/Al composites from an Al–Ti–B4C system

The TiC–TiB2/Al composites were fabricated by self-propagating high-temperature synthesis (SHS) from Al–Ti–B4C compacts. The addition of Al to the Ti–B4C reactants facilitates the ignition occurrence, lowers the reaction exothermicity, and modifies the resultant microstructure. The maximum combustion temperature and combustion wave velocity decrease with the increase in the Al amount. The B4C particle size exerts a significant effect on the combustion wave velocity and the extent of the reaction, while that of Ti has only a limited influence. The reaction products are primarily dependent on the B4C particle size and the Al content in the reactants. Desired products consisting of only the TiC, TiB2, and Al phases could be obtained by a cooperative control of the B4C particle size and the Al content.