Synthesis and Characterization of Novel Al-Matrix Composites Reinforced with Ti3SiC2 Particulates

In this paper, we report for the first time, the synthesis and characterization of novel Ti3SiC2 reinforced Al-matrix composites. All the composites were cold pressed and sintered in the temperature range of 700-750 A degrees C for 5-30 min in an inert Ar atmosphere. Microstructure analysis by scanning electron microscopy and phase analysis by x-ray diffraction confirmed that there was minimal interfacial reaction between Ti3SiC2 particles and Al. The addition of Ti3SiC2 enhanced the mechanical performance of the composites. For example, the pure Al samples had a yield strength of 97 +/- A 6 MPa, where as the volume fraction of Ti3SiC2 was increased to 5 and 10 vol.% in the composites, the yield strength increased significantly to 212 +/- A 27 and 273 +/- A 52 MPa, respectively. As the volume fraction of Ti3SiC2 was further increased to 20 and 35 vol.%, the yield strength mildly increased to 278 +/- A 48 MPa, and then decreased to 134 +/- A 20 MPa, respectively. The decrease in yield strength after 35 vol.% Ti3SiC2 addition in the Al matrix was attributed to the presence of higher amount of porosity in these samples. The addition of Ti3SiC2 particles also had a beneficial effect on the tribological performance of these composites against alumina substrates.