Ignition and Combustion of Mechanically Activated Powder Compositions (Review). I. Ignition
A. S. Rogachev
Merzhanov Institute of Structural Macrokinetics and Materials Science, Russian Academy of Sciences, Chernogolovka, Russia
Keywords: ignition, preliminary mechanical activation, SHS, thermites, sensitivity to heat and shock
Abstract
This paper presents a critical review of experimental results and theoretical models for the effect of mechanical activation on the ignition of powder mixtures in gasless and filtration combustion and the ignition of thermite compositions. It is shown that all available data clearly indicate an increase in the sensitivity of powder compositions for thermal initiation, but in the case of shock initiation, the sensitivity does not always increase. The change in the sensitivity is due to the combined effect of two factors: an improvement in the contact between reactants and a decrease in the activation energy of the chemical reaction. It is proposed to use the mechanical activation factor taking into account the change in contact area and activation energy to describe the sensitivity of activated compositions.
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