A kinetic model for the field-activated synthesis of MoSi2/SiC composites: simulation of SPS conditions

Abstract A modeling study was carried out to simulate the direct synthesis of MoSi 2 –SiC composites from the elements using field activation. The study was made to simulate the experimental process of spark plasma synthesis (SPS), which has been utilized previously to simultaneously synthesize and densify materials, including nanophases. The results show a temporal dependence for the formation of the two products. The dependence of the reaction wave dynamics on composition was also investigated. A transition from volume combustion, in which the reactants are converted instantly to the products throughout the entire sample, to a wavelike reaction, in which the conversion front traverses the sample in a finite time, is shown to depend on sample size and product. Conversion fronts traverse the sample as concentric waves propagating outward or inward depending on the composition of the composite and on the die conductivity.