Preparation and R-curve properties of laminated Si/SiC ceramics from paper

Laminated Si/SiC ceramics were synthesized from paper via impregnation with phenolic resin, followed by lamination and carbonization of the paper-resin laminates and subsequent infiltration and reaction with liquid silicon at a temperature of 1550 °C for 10-90 min. Due to the capillarity infiltration and in situ reaction with liquid silicon, intrinsic micro- and macrostructure in the carbon preform was retained within the final ceramics. The XRD, TGA, and microscopy analysis indicated that the final material exhibited a distinguished laminar structure with alternating arrangement of SiC and silicon layers. The thick SiC layer was composed of beta-SiC and a little of free silicon and un-reacted carbon. Studies on the evaluation of R-curves behavior by the indentation-strength method indicated a strong R-curve behavior for the Si/SiC composites.