<p>Silicon carbide (SiC) ceramic materials were fabricated via the combination of direct ink writing (DIW) and reactive melting infiltration (RMI) techniques. The effects of the carbon black-to-silicon carbide (C-to-SiC) ratio on the rheological properties of the slurry, as well as the microstructure and mechanical performance of the resulting SiC ceramics were systematically investigated. The experimental results demonstrate that, as the carbon black content increases from 9vol% to 18vol%, the viscosity, yield stress, and equilibrium modulus of the slurry all exhibit a corresponding increase, contributing to enhanced dimensional precision of the green body. After high-temperature heat treatment, the linear shrinkage in the vertical direction decreases from 8.59% to 6.88%. The prepared SiC ceramic materials display densities in the range of 2.70 – 2.85 g/cm³ and porosities ranging from 0.39vol% to 3.99vol%, indicating an improvement in densification. With the increase in carbon black content, the free silicon content in the ceramics decrease, while the residual carbon content increase. Mechanical testing results reveal that the SiC ceramics fabricated from slurries with 12vol% and 15vol% carbon black content achieve the highest flexural strength and modulus, reaching 287.74 MPa and 274.10 GPa, respectively. A reasonable C-to-SiC ratio helps to generate more SiC content (especially nanoscale β-SiC) and retain less residual Si, thereby forming a finer microstructure. Combined with less residual C, higher mechanical properties can be obtained.</p>