The aims of this study were to observe the microstructure and the tormed phases of Ti-Al intermetallic compound system composites made by spark plasma-combustion synthesis and to investigate the phase formation mechanism.
During the spark plasma sintering of the Ti:Al=1:1 powders, combustion synthesis was indicated by the abruptly shringkage in sample volume at Al melting point. The microstructure and the formed phase of spark plasma-combustion synthesized composites varied according to Ti particle size. For example, TiAl3 phases were formed when 100μm Ti powders were used, and TiAl, Ti2Al and Ti3Al phases were formed when 10μm Ti powders were used (the sintering temperature was 973K). The formation mechanism of compounds using spark plasma sintering has two processes; combustion synthesis at Al melting point and diffusion in the high temperature region.