Abstract Ti‐Si targets are used in cutting tool coatings and semiconductor gate dielectrics. This study investigated densification mechanisms, phase evolution, and reactive sintering kinetics of Ti‐25at%Si targets fabricated by spark plasma sintering using blended Ti and TiSi 2 powders. Significant shrinkage was observed between 600°C and 900°C with minor solid‐state reactions. At 1000°C, reactions intensified, promoting further densification. The creep model determines the stress exponent ( n ) and apparent activation energies, revealing the transition from a grain boundary diffusion‐dominated densification mechanism under high effective stress ( n = 1.5, activation energy 108 ± 4 kJ/mol) to a dislocation‐climb‐assisted densification mechanism under low effective stress ( n = 3, activation energy 205 ± 14 kJ/mol). Transmission electron microscopy confirms dislocation climb, while grain boundary diffusion is supported by the formation of new phases (such as Ti 5 Si 3 ) generated through diffusion reactions. The Johnson–Mehl–Avrami kinetic equation was used to fit the reactive sintering experimental data around 1000°C, yielding an Avrami exponent of 1.16 ± 0.15, indicating that the reaction proceeds via two‐dimensional nucleation and growth. The activation energy for Ti 5 Si 3 formation, calculated using the Arrhenius equation, is 60 ± 7 kJ/mol, which is lower than the 205 kJ/mol obtained from the direct reaction between Ti and Si.
Li et al. (Tue,) studied this question.