ИСТИНА

Combustion behavior of triaminoguanidine nitrate (TAGN) has been investigated in wide pressure range and the detailed combustion mechanism of TAGN has been proposed. Temperature profiles in the TAGN combustion wave were measured with thin tungsten-rhenium microthermocouples. It has been shown that the surface temperature in combustion of TAGN, as well as for other onium salts, is controlled by process of dissociation. The burning rate at low pressure range is governed by processes in the condensed phase. The kinetic parameters of the burning rate controlling chemical reaction have been estimated and it has been shown that TAGN thermal decomposition reaction in the molten layer at the surface temperature controls the TAGN combustion. At pressure interval of 1-20 atm the heat release in the condensed phase provides completely amount of heat required for warming-up and melting, heat flux from the gas phase is spent only for evaporation of non-decomposed TAGN and has no effect on burning rate. The determined kinetic parameters of leading chemical reaction at combustion of TAGN allow explaining why TAGN exhibits high affectivity as activator of combustion of various AN-based propellant compositions. Having essentially low thermal stability in comparison with AN, TAGN in AN-based mixtures acts as an additional heat source in the molten layer of AN.