Formation and growth mechanism of TiC terraces during self-propagating high-temperature synthesis from a FeTiC system

TiC terraces were prepared in situ through self-propagating high-temperature synthesis (SHS) reaction with 10 wt.% FeTiC elemental powder mixtures. The formation and growth mechanism of TiC during the SHS process were explored. The results of combustion wave quenching experiment showed that the formation mechanism of TiC could be ascribed to the dissolution of C into FeTi melt and the precipitation of TiC from the saturated melt. The X-ray diffraction, field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analyses revealed that TiC terraces grew through the layer-by-layer mechanism along [100] direction, while thin TiC monolayer was formed by two-dimension (2D) nucleation growth mode.

► TiC terraces were prepared through SHS reaction with FeTiC powder mixtures.
► TiC grains were formed by the dissolution–reaction–precipitation mechanism.
► TiC terraces grew through the layer-by layer mechanism along [100] direction.