REACTION SYNTHESIS OF TITANIUM SILICIDES VIA SELF-PROPAGATING REACTION-KINETICS

Self-propagating exothermic reactions in the titanium-silicon system i nduced by mechanical milling, shock loading, and thermal ignition of e lemental powder mixtures have been investigated, After an induction pe riod of 3 h, the 5Ti + 3Si powder mixture abruptly reacted during mill ing to form single-phase Ti5Si3 via a mechanically induced self-propag ating reaction (MSR). Moreover, the formation of porous Ti5Si3 solid i ndicated that the melting of powder particles had occurred during the mechanical alloying process. The Ti + Si powder mixture also reacted v ia the MSR mode, but the end-product was multiphase. Shock and combust ion synthesis (thermal-explosion mode) experiments essentially produce d the same result.