Relationship between Field Direction and Wave Propagation in Activated Combustion Synthesis

Abstract

Using experimental and modeling studies, the effect of field direction on the field‐activated combustion synthesis of SiC was investigated. Field application imposed in a direction perpendicular to wave propagation resulted in enhancement: the wave velocity increased linearly with an increase in field strength. For field application parallel to wave propagation, two cases were considered: confined and nonconfined areas of impacted energy from an ignition source. In the confined case both experimental (using laser ignition) and simulation studies were made. Both showed the establishment of a two‐front combustion with waves moving to opposite sides in a direction perpendicular to the field. In the nonconfined case, initial waves propagated in a direction parallel to the field but were independent of field strength. The results are interpreted in terms of a model in which the current is confined to the combustion zone, adding another source of heat to the combustion process, at a rate of σE2 (J·cm‐3·s‐1).