Processing of Continuous Carbon Fibre Reinforced ZrB₂-SiC Composite Through In-Situ Matrix Development

C_f-ZrB₂-SiC based ultra-high-temperature ceramic matrix composites (UHTCMCs) are an Emerging material system. This work aims to fabricate a carbon fibre (C_f) reinforced ZrB₂-SiC composite through an in-situ ZrB₂-SiC matrix formation technique, using zircon, B₄C, and phenolic resin as raw materials via the boro/carbo thermal reduction (BCTR) method. In the initial step, a slurry of zircon (ZrSiO₄), B₄C, and phenolic resin was infiltrated into a carbon fibre preform, followed by curing, pyrolysis, and heat treatment at 1600 °C. This resulted in a porous C_f-ZrB₂-SiC composite. This process enables the in-situ formation of a matrix containing uniformly dispersed submicron-sized ZrB₂ & SiC particles in the composite without damaging the fibres. To further increase the density, samples were subjected to two different processing routes: (a) sintering the composite at 2000 °C and (b) chemical vapour infiltration (CVI) of SiC in the composite. The densification behavior and Young’s modulus of the composites were analysed.