INCREASE OF THE STABILITY OF THE PROCESS OF PYROTECHNIC MIXTURES COMBUSTION THROUGH THE ADDITION OF ORGANIC SUBSTANCES

Abstract

Ignition and subsequent fire-hazardous destruction of products are usually preceded by external thermal effects to which they are subjected. This leads to premature ignition and explosive development of burning charges based on compacted mixtures of oxidizing powders and metal combustibles and further fire-hazardous destruction. Prevention of forced fire-hazardous destruction of products in the event of external thermal effects becomes of significant practical importance. Prevention methods should be based on studies of the development processes of the combustion of pyrotechnic mixture charges in various external conditions. Prevention of forced fire-hazardous destruction of products in the event of external thermal effects acquires significant practical importance. Prevention methods should be based on studies of the development processes of the combustion of pyrotechnic mixture charges in various external conditions. Currently, the issue of the influence of various technological parameters and external conditionson the processes of development of combustion of two-component pyrotechnic mixtures has been sufficiently investigated. However, there are no systematic studies of the influence on the combustion process of the indicated mixtures of additives of various organic substances, which, as shown by separate studies for paraffin, stearin, naphthalene, anthracene additives, not only contribute to the improvement of the technology of manufacturing their charges, but also lead to a slowdown in the combustion process of the mixtures with further its stabilization. The purpose of the work is to establish the regularities of the influence of additives of various organic substances in the composition of pyrotechnic mixtures of oxidizing powders and metal fuels on the speed and stability of the development of their combustion. A wide class of organic substances has been established, the introduction of which in the form of small additives (up to 10%) into the composition of pyrotechnic mixtures based on powders of metalfuels and oxidizers leads to a decrease in the speed and increase in the resistance of their combustion process to external influences (increased heating temperatures, external pressures) for different ranges of changes in technological parameters of mixtures (ratio and dispersion of components, compaction coefficient). With a decrease in the coefficient of excess oxidant in the mixture, the dependence of the burning rate on the amount of the additive increases, regardless of its dispersion. Additions of stearin and thiocol in the mixture of Al + NaNO3 and Zr + NaNO3, on the contrary, lead to an increase in the burning rate of these mixtures, which is due to an increase in the reactivity of Al and Zrin the presence of gaseous decomposition products of stearin and thiocol at elevated heating temperatures, which contribute to a sharp decrease in ignition temperature of metal fuel particles and lead to a decrease in the stability of the combustion process of mixtures, especially under conditions of increase dexternal pressure (an increase in the index in the combustion law with an increase in the amount of the additive).