Effect of Ag and TiSiC on Tribological Properties of TiAl Matrix Self-lubricating Composites at Room and Increased Temperatures.

Dry sliding tribological properties of TiAl matrix self-lubricating composites (TMSC) containing Ag, TiSiC, Ag and TiSiC were investigated from 25 to 800 °C under ball-on-disk test conditions against SiN counterface under the same conditions of 10 N-0.234 m/s. The results indicated that the tribological properties were strongly dependent on the lubricant additives. TMSC with the addition of Ag and TiSiC (TAT) exhibited the lower friction coefficients (0.32-0.43) and less wear rates (1.23-4.13 × 10 mm Nm) in the wide temperature range of 25-800 °C. The excellent tribological properties of TAT over the wide temperature range were attributed to the synergetic effect of Ag and TiSiC lubricants, silver diffusion forming a rich-silver smooth tribo-film on the frictional surface of TAT at low and moderate temperatures from 25 to 400 °C, while TiSiC oxidation reaction forming rich-oxide tribo-film on the worn surface of TAT at higher temperatures of 600 and 800 °C. [ABSTRACT FROM AUTHOR]