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.