Ultra-high-temperature materials demonstrate excellent performance, with high-melting-point carbides like titanium carbide (TiC) widely used across industries. With advancing technology, demands for material performance are increasing. Although nano-scale carbides offer advantages, conventional preparation methods face significant challenges. In this study, nano-TiC powder was synthesized using combustion synthesis in the TiO₂-C-Mg system with NaCl as a diluent. This approach effectively mitigates excessive grain growth caused by high combustion temperatures, enabling large-scale production of high-purity nano-TiC. NaCl addition significantly reduces TiC particle size. When NaCl content reaches 100 wt.%, the average particle size decreases from 178 nm to 74 nm, with a specific surface area of 15.203 m²/g. Particle refinement results from NaCl’s dual effects during formation and growth stages. NaCl lowers adiabatic temperature via endothermic phase transformation and creates a liquid-phase environment that enhances diffusion and undercooling, promoting nucleation while suppressing grain growth. This study offers technical guidance for scalable production of nano-TiC with controlled particle size.

Keywords: Salt-assisted combustion, TiC nanopowders, Controllable particle size, Formation mechanism.