Effect of Ti/Si ratio on the products of laser igniting self-propagating high-temperature synthesis in Cu–Ti–Si system

The production of titanium silicide, from elemental powder compacts was successfully synthesized by laser ignited self-propagating high-temperature synthesis (SHS) of Cu–Ti–Si system in this study. Effects of Ti/Si ratio on the combustion characteristics, combustion temperature, the composition and microstructure of final products were studied. The results showed that the combustion process was preceded by the fast propagation of a self-sustained combustion front, followed by vigorous bulk combustion, furthermore, the combustion temperature increased with the increasing of Ti/Si ratio. When Ti/Si ratio is 1:2, the polygon-like shape TiSi2 phase was the dominant phase, minor amounts of Ti5Si3 and Cu3Si were detected in the final product; when Ti/Si ratio is over 1:2, the amounts of TiSi2 and Ti5Si3 phases decreased and increased, respectively. Especially, the cobblestone-like shape Ti5Si3 as the dominant phase was identified in the final product when Ti/Si ratio is 5:3.

► The SHS process includes: preheat, ignition, self-propagating, thermal explosion. ► The peak value temperature increases with the increasing of Ti/Si ratio. ► The Ti5Si3 lattice planes increase when Ti/Si ratio increases. ► Ti5Si3 phases increases and the microcracks disappear when Ti/Si ratio increases.