A coupled infiltration kinetics model for fabricating ceramic composites by reactive melt infiltration: A quantitative study using Hf-Zr-Si and Hf-Zr-Ti-Si multi-component alloys

Reactive melt infiltration (RMI) of multi-component alloys offers a promising route to C/multi-component carbide composites (MCC), but a quantitative framework coupling infiltration kinetics with pore evolution is lacking. This work establishes such a model via a modified Washburn equation with time-dependent capillary radius, using Hf-Zr-Si and Hf-Zr-Ti-Si alloys as model systems. Melt properties (surface tension, viscosity, wetting angle) were determined thermodynamically and experimentally. Pore evolution kinetics were quantified by rate constant k_p from reaction layer growth. The model reveals distinct behaviors: Hf-Zr-Si exhibits strong temperature-dependent critical pore size r_limit and rapid pore closure, whereas Hf-Zr-Ti-Si displays stable r_limit and slower sealing, enabling deeper infiltration and higher densities. Experiments with C/C preforms (1.20–1.50 g/cm³) at 1700–2000 °C validate predictions. Microstructural analysis underscores the critical role of temperature in governing carbide homogenization. This work provides a framework for designing RMI processes for advanced C/MCC composites.