Preparation and characterisation of carbon fibre-reinforced laminated woodceramics

To improve the structure and basic performance, carbon fibre-reinforced woodceramics with a laminated structure were prepared by using liquefied wood and carbon powder as matrix materials and carbon fibre as a reinforcing material through structure and process designs with the establishment of a unit structure model thereof. Basic performance tests indicated that the sintering temperature and content of liquefied wood played important roles. The apparent density first reduced, later increased and then decreased with increasing sintering temperature; the apparent porosity decreased with increasing liquefied wood content. Scanning electron microscopy showed that the woodceramics presented a clear laminated structure and tight joints between glassy carbon (GC) and the embedded carbon fibres. There was an interface layer found between the amorphous carbon and GC. Meanwhile, it still partially retained the natural structural characteristics of wood. Raman spectrum detection verified that raising the sintering temperature could increase the number of graphite crystallites and the orderliness of their arrangement. Transmission electron microscopy showed that the specimens formed at higher temperatures presented clear lattice fringes. In addition, the laminated structure and the application of reinforced carbon fibre greatly enhanced the bending strength, elastic modulus, and fracture toughness.