An inorganic salt strategy to fabricate C/C-ZrC-SiC composites with enhanced mechanical and ablation resistance by PIP method

s To reduce the cost of C/C-ZrC-SiC composites, an inorganic salt strategy was proposed for fabricating these composites using the PIP method. The precursor solution, composed of zirconium tetrachloride, tetraethoxysilane, and furfuryl alcohol, exhibits lower viscosity, facilitating more efficient infiltration into the C/C matrix and reducing porosity in the final composite. Fine ZrC and SiC particles, with an average particle size of 2.03 μm, were homogeneously distributed within the composite matrix. The resulting material demonstrated a flexural strength of 193.2 MPa, along with linear and mass ablation rate of 0.03 μm/s and 0.10 mg/s, respectively. The uniform distribution of fine ZrC and SiC particles within the dense matrix significantly enhances mechanical properties and ablation resistance. During ablation, these particles promote the formation of a protective oxide scale consisting of a dense outer ZrO 2 layer and an inner SiO 2 layer. The dense ZrO 2 layer effectively retards oxygen diffusion into the composite, providing excellent resistance to mechanical erosion, while the continuous SiO 2 layer minimizes the ingress of oxidizing gases, further enhancing ablation resistance. This study demonstrates that the inorganic salt strategy can be used to fabricate C/C-ZrC-SiC composites at a lower cost while achieving superior properties, offering a promising approach for producing C/C-UHTCs composites.