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Gamma-based titanium aluminides have great potential in the automotive industries (e.g. valves in a car engine),but tribological property could be one of the crucial factors in determining the life and performance of a titanium aluminide part. A surface modification technique, namely ceramic conversion (CC) treatment has been developed to improve the tribological properties of a γ-based titanium aluminide (Ti-48Al-2Nb-2Cr-B), and the surface properties were fully characterised. The results indicate that ceramic conversion treatment can produce an oxide layer consisting of a top TiO2 surface followed by a mixture of TiO2 and Al2O3. Such hardened layer has significantly improved the load-bearing capacity and wear resistance of the intermetallics, as evidenced by an increase of scuffing load up to 4 times and a wear rate reduction of two orders of magnitude. The coefficient of friction has also been reduced from 0.5-0.7 for the untreated to an average of 0.22 for the CC-treated alloy under dry sliding contact conditions.