Abstract The present study explores the densification and mechanical properties of novel Al 4 O 4 C ceramics, which are enhanced by the incorporation of Y 2 O 3 additives and the utilization of spark plasma sintering. A significant observation was the presence of a native oxide layer on the surface of the Al 4 O 4 C powder, predominantly composed of Al 2 O 3 . Following sintering at 1723 K, Al 4 O 4 C was established as the primary phase, with Al 2 O 3 and Y 3 Al 5 O 12 (YAG) identified as secondary phases. Comprehensive experimental analysis, complemented by molecular dynamics simulations, revealed the mechanism of YAG on the grain growth behavior of Al 4 O 4 C. The findings demonstrated that an optimal Y 2 O 3 content of 3 wt% resulted in a maximum flexural strength of 272 MPa, a fracture toughness of 2.01 MPa·m 1/2 , and a Vickers hardness of 15.1 GPa. This research offers valuable insights into the densification process and the enhanced mechanical properties of ternary carbides, paving the way for their further applications.
Cheng et al. (Tue,) studied this question.