Abstract
Powder metallurgy is expected to be processing technology of titanium aluminides with high strength, which are candidates for lightweight high-temperature materials in near future, because more uniform materials having finer microstructures can be synthesized through powder metallurgical processes than through casting processes. However, the fine microstructures become coarser due to grain growth and therefore the materials become weak during exposure to high temperatures. Reinforcement of titanium aluminides by dispersion of ceramic particles and/or fibers into titanium aluminides matrix is expected to restrain the grain growth by their pinning effect. In this study, a blend of Ti, Al and B powders was mechanically alloyed and sintered by spark plasma activated sintering technique to synthesize TiAl intermetallic material with TiB2 particulate dispersion. As a result, Ti-Al intermetallic powder of non-equilibrium phase was made by mechanical alloying of Ti-Al-B powder mixture and fully dense TiAl-TiB2 composite material was synthesized by sintering the powder at 1223K, 49MPa for 300s.
