Dry-Sliding Tribological Properties of TiAl/Ti2AlC Composites

The microstructure, mechanical and dry-sliding tribological properties of TiAl-based composites with 20 and 40 vol% in situ formed Ti2AlC, produced by hot press sintering process, are investigated. The microstructural characterization reveals that Ti2AlC phase is in the form of spherical particles and large blocks, and the quantity of the blocks increases with Ti2AlC content. This difference in the morphology and distribution of the Ti2AlC phase leads to the discrepancy of the wear resistance of the composites. In contrast to the Ti-46Al-2Cr-2Nb intermetallics, the dry-sliding wear resistance of the TiAl/Ti2AlC composites first declines slightly and then enhances with the Ti2AlC content. Furthermore, the TiAl/40 % Ti2AlC composite shows low wear rate at higher sliding speed.