Micropyretic/combustion synthesis is a technique whereby a material is synthesized by the propagation of a combustion front across a powder. Heterogeneous distributions of reactants and a diluent are common during micropyretic synthesis when powders are mixed and the conventional modelling treatments thus far have only considered uniform systems. Heterogeneities in a composition are thought to result in local variations of thermophysical/chemical parameters for the reactant, such as density, heat capacity and thermal conductivity. The result is changes in combustion temperature, propagation velocity and the propagation pattern of a combustion front. This study investigates the impact of heterogeneities during micropyretic synthesis with Ni + Al. Correlations of heterogeneities in the reactants and diluent with propagation velocity and combustion temperature are also investigated. In addition, a map, considering concurrent heterogeneities in the reactants and diluent, has been generated to provide a better understanding of the effect of heterogeneities on propagation velocity during micropyretic synthesis.
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