A time-resolved x-ray diffraction study of Ti₅Si₃ product formation during combustion synthesis

Time-resolved x-ray diffraction (TRXRD) was performed during Ti₅Si₃ synthesis by the self-propagating high-temperature synthesis mode for different Ti size fractions. It was determined that the time for product formation (ca. 15 s) was independent of Ti particle size. However, the formation of Ti₅Si₄ phase occurred when relatively large titanium particles were used. A simultaneous measurement of the temperature and TRXRD allowed us to attribute the shifting of XRD peaks at high temperature to thermal expansion of the Ti₅Si₃ product. The thermal expansion coefficients differ for different crystal planes, and their numerical values compare well with those reported previously in the literature.