Fabrication of SiC_f/Ti₃SiC₂ composites with high thermal conductivity by spark plasma sintering

Compared to densification process for SiC matrix to obtain nuclear-grade SiC fiber-reinforced SiC matrix (SiC_f/SiC) composites, it would be time-saving and less expensive to employ spark plasma sintering (SPS) process for the densification of nuclear-grade SiC fiber-reinforced Ti₃SiC₂ matrix (SiC_f/Ti₃SiC₂) composites. In this work, Ti₃SiC₂ matrix was densified by SPS process to replace SiC matrix for the fabrication of SiC_f/Ti₃SiC₂ composites. By introducing β-SiC layer on the fiber, interfacial reaction between SiC fibers and Ti₃SiC₂ matrix was effectively avoided. Microstructure and thermal properties of as-obtained SiC layer coated SiC fiber-reinforced Ti₃SiC₂ matrix (SiC_f-CS/Ti₃SiC₂) composite were studied. Results showed that the densification of SiC_f-CS/Ti₃SiC₂ composite was improved by infiltration behavior of Ti₃SiC₂. With decrease in porosity, SiC_f-CS/Ti₃SiC₂ composite exhibited thermal conductivity of 24.3 W m⁻¹ K⁻¹ at room temperature, with excellent stability (21.5 W m⁻¹ K⁻¹ at 1000 °C). Moreover, thermal transport property of SiC_f-CS/Ti₃SiC₂ composite was also improved compared to that of SiC_f/Ti₃SiC₂ composite. Findings of this work would be helpful for the development of SiC_f/Ti₃SiC₂ composites for various applications.