Rapid NITE sintering of high strength and toughness SiCf/SiC composites by an internal Joule heating of 3D conductive carbon networks

SiC f /SiC ceramic matrix composites (CMCs) are prime candidates for hot-section components in next-generation aero-engines due to their exceptional high-temperature strength and low density. However, the rapid and efficient densification of components remains the critical bottleneck that severely hinders their widespread engineering applications. In this work, a rapid nano-infiltration and transient eutectic-phase (NITE) sintering method to fabricate high performance SiC f /SiC composites. By utilizing the internal Joule heating of 3D conductive carbon networks, rapid densification under low pressure was successfully achieved. The influence of sintering aid content on the microstructure and mechanical properties of the composites was investigated. SiC f /SiC composites can be densified with 12 wt% sintering aids within 10 min. The sintering aids are present at the grain boundaries in the form of an Al-Y-O amorphous phase and Y 3 Al 5 O 12 crystals. The extremely short sintering time prevents damage to the fibers and the fiber interfaces, thereby enabling the fabrication of composites with favorable mechanical properties. The optimum flexural strength and fracture toughness of the SiC f /SiC composites are 411.41 ± 37.42 MPa and 13.51 ± 0.84 MPa m 1/2 , respectively. This work can provide new strategies and guidance for the rapid fabrication of various ceramic matrix composites with excellent mechanical properties.