Microstructure evolution, mechanical and tribological properties of Ti₃(Al,Sn)C₂/Al₂O₃ composites

In this paper, in situ formed Ti₃(Al,Sn)C₂/Al₂O₃ composites were fabricated by sintering the mixture of Ti₃AlC₂ and SnO₂. The Al atoms could diffuse out of the Ti₃AlC₂ layered structure to react with SnO₂, resulting in the formation of Ti₃(Al,Sn)C₂ solid solution and Al₂O₃. When the SnO₂ content was 20 wt.%, the sintered Ti₃(Al,Sn)C₂/Al₂O₃ composite exhibited the best overall mechanical properties, because of the optimized cooperative strengthening effect of solution strengthening and Al₂O₃ enhancement. When the SnO₂ content increased up to 30 wt.%, the flexural strength and fracture toughness of Ti₃(Al,Sn)C₂/Al₂O₃ composite dramatically decreased on account of the large accumulation of generated Al₂O₃. Moreover, according to the SiC ball-on-flat wear tests, it was found that the wear resistance of Ti₃(Al,Sn)C₂/Al₂O₃ composites was significantly improved as the SnO₂ content increased.