Abstract The aim of the present study was elucidating reaction mechanism of the TiO2–Al–C–Fe system during self-propagating high-temperature synthesis. Results showed that the addition of Fe to the 3TiO2+4Al+3C reactants from 1.21 mol to 1.71 mol led to instability of the combustion reaction and the formation of nano-crystalline TiC. Differential thermal analysis and X-ray diffraction analysis results demonstrated that during heating of the 3TiO2–4Al–3C–1.71Fe mixture, four sequential exothermic reactions occurred at 588, 913, 1036 and 1173 °C. They were corresponding to the solid state reaction between Fe and Al, the reaction of Al melt with TiO2, the formation of Ti3Al, and finally, the establishment of TiC and Fe3Al. Moreover, the ignition temperature of the reaction between Ti and C decreased in the presence of Fe. Microstructural examinations of Fe particles showed that the formation of Fe-rich melt accelerated the dissolution of C, Al, and Ti into the molten Fe droplets. Finally, when the melt saturated from C and Ti, TiC particles precipitated through the dissolution-precipitation mechanism.

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