Low-content addition of rGO refines SiC fiber pore structure for strength and toughness enhancement

Optimizing the composition-structure and enhancing the strength and toughness of silicon carbide (SiC) fibers is critical for effective reinforcements in ceramic matrix composites (CMCs). Herein, reduced graphene oxide/SiC-o (rGO/SiC-o) fibers with 1.0 wt% rGO with modulated oxygen contents were fabricated via the polymer-derived ceramic (PDC) method. Key findings demonstrate that rGO inhibits SiC x O y amorphous phase decomposition during the preparation process, suppresses pore growth to refine the microstructure of fibers. Concurrently, graphene-matrix interlocking and crack-bridging/pull-out mechanisms synergistically enhance mechanical performance. As a consequence, rGO/SiC-o-I fibers exhibit 16.8 % higher elongation at break and 24.4 % greater breaking energy than rGO-free counterparts. • rGO/SiC-o fibers with low rGO addition were fabricated by PDC method. • rGO effectively refines the pore structure of SiC fibers during pyrolysis. • The fabricated rGO/SiC-o fibers have more excellent strength and toughness.