Effect of field‐assisted sintering parameters on microstructure of carbon fiber‒silicon carbide composites

Abstract The objective of this study was to investigate the adaptation of field‐assisted sintering technology (FAST) to a prepreg approach for producing continuous‐fiber C/SiC composites. This study explored the effects of process parameters for FAST on tow infiltration, porosity, and crack propagation in C/SiC composites. The C/SiC composites were produced from prepregs using a nano‐infiltration transient eutectic process (nano‐SiC powder infiltration and transient eutectic phase). Rapid process cycles (cycle times of 10s of minutes) yielded fully dense laminates at sintering temperatures of 1700°C‒1900°C. Microstructural analysis of polished sections revealed 0%‒1% porosity, and bending tests were performed to reveal the effects of process history. Increasing dwell time at the peak sintering temperature did not strongly increase fiber dissolution but increased SiC grain densification in the matrix.