Fabrication of (SiC_f+SiC_w)/SiC composites by CVI combined with tape casting

Abstract SiC ceramics toughened by both continuous SiC fibers and SiC whiskers were firstly prepared and studied in this work. SiC fiber fabrics were laminated with SiC_w green bodies which were fabricated by tape casting one by one. Then the laminated SiC_f+SiC_w preformance was densified by chemical vapor infiltration (CVI). Results showed that the composites toughened by both SiC fibers and SiC whiskers have outstanding bending strength, fracture toughness and fracture work as 383±19 MPa, 11.2±0.3 MPa m^1/2 and 4.9±0.16 kJ/m², respectively. Introducing SiC fibers into laminated SiC_w/SiC composites could increase the strength and toughness of the composites by the pull-out of SiC fibers in SiC_f+SiC layers and increasing crack propagation path between different layers. Cracks deflect in different layers and interface could extend the crack propagation path and increase the energy consumption capacity, thereby the fracture toughness and fracture work were increased.