Strengthening and tribological surface self-adaptability of Ti3AlC2 by incorporation of Sn to form Ti3Al(Sn)C2 solid solutions

Ti3Al1.2−xSnxC2 (x=0, 0.2, 0.4) solid solutions were synthesized using a two-time hot-pressing sintering method. The lattice parameter a was observed to increase slowly while the lattice parameter c remained almost unchanged with an increase in the Sn content in a Ti3Al1.2−xSnxC2 solid solution. Significant strengthening was observed after incorporation of 0.2Sn and 0.4Sn to form Ti3Al(Sn)C2 solid solutions. The flexural strengths of these compounds were measured to be 560 MPa and 620 MPa, respectively; these values are 51% and 67% higher, respectively, than the strength of Ti3AlC2. Tribological surface self-adaptability after the incorporation of Sn was also investigated at a sliding speed of 30 m/s under normal loads of 20~80 N. The results showed that the friction coefficient could be adapted to fall within the range of 0.13~0.33 after the incorporation of different amounts of Sn. Tribological surface self-adaptability mechanisms were also discussed.