Microstructure Evolution of Ti-Al-C System Composite

Ti-Al-C composite was fabricated by infiltration-in situ reaction. The as-cast material was prepared by pressing molten pure aluminum into the preform composed of titanium particles and carbon fibers. In situ reacted samples were obtained by heating the as-cast material from 600 to 1000 °C, and holding for 1 h at different temperatures. The morphology and elemental composition of samples were analyzed by scanning electron microscope and Energy dispersive X-ray, respectively. In addition, the phase composition of products was inspected by X-ray diffraction. Results show that TiAl3 and Al4C3 are formed at low temperature; with increasing of temperature, TiAl3 decomposes and TiC precipitates; at high temperature, the oxidation occurs resulting in the formation of Al2O3. The mechanism of Ti-Al-C system composite during in situ reaction procedure is as following: formation-decomposition-precipitation-oxidation.