Mechanistic investigation of electric field-activated self-propagating reactions:: experimental and modeling studies

The mechanism of electric field-activated self-propagating reactions is investigated using the combustion Front quenching technique. In particular, previously published experimental results obtained through the field-activated combustion synthesis (FACS) of beta -SiC, TaC, Ti3Al and B4C-TiB2 are re-examined and compared. Pre-combustion and combustion stages involved during synthesis wave propagation are postulated for all systems. Subsequently, modeling results aimed at simulating the process where an electric field-activated, self-propagating reaction takes place are presented. In particular, a one-dimensional model of FAGS technique is developed to simulate the rapid quenching of the reaction during its progress as the applied field is turned off. A rate expression which accounts for the influence of temperature, particle size, compaction density, reactant stoichiometry, and inert content is included in the model. (C) 2001 Elsevier Science Ltd. All rights reserved.