Pressureless sintered Al4O4C ceramics with Y2O3 addition

Al 4 O 4 C ceramics were prepared via pressureless sintering, and the effects of Y 2 O 3 content on their densification and mechanical properties were studied. When sintered at 1800 °C for 3 h, Al 4 O 4 C was identified as the major phase, while Y 3 Al 5 O 12 formed as a secondary phase. The in situ YAG effectively enhanced the densification of the ceramics and contributed to the improvement in their mechanical properties. The results indicate that the optimization of Y 2 O 3 content plays a crucial role in achieving favorable mechanical performance. Specifically, the bending strength peaked at 197.3 MPa with 3 wt% Y 2 O 3 , while the highest Vickers hardness and fracture toughness of 14.3 GPa and 2.6 MPa·m 1/2 were obtained with 5 wt% Y 2 O 3 . This study lays a foundation for the future research and application of Al 4 O 4 C ceramics.