Reaction synthesis of titanium silicides via self-propagating reaction kinetics

Self-propagating exothermic reactions in the titanium-silicon system induced by mechanical milling, shock loading, and thermal ignition of elemental powder mixtures have been investigated. After an induction period of 3 h, the 5Ti + 3Si powder mixture abruptly reacted during milling to form single-phase Ti ₅Si ₃ via a mechanically induced self-propagating reaction (MSR). Moreover, the formation of porous Ti ₅Si ₃ solid indicated that the melting of powder particles had occurred during the mechanical alloying process. The Ti + Si powder mixture also reacted via the MSR mode, but the end-product was multiphase. Shock and combustion synthesis (thermal-explosion mode) experiments essentially produced the same result.