Ballistic effectiveness of Zr-containing composite solid propellants as a function of binder nature and mass fraction

This paper considers the effects of binder mass fraction on the properties of energetic formulations based on zirconium and zirconium hydride. These ingredients, replacing aluminum in solid rocket motors with low vehicle performance coefficient, may increase the propellant ballistic effectiveness, thanks to the resulting higher density and notwithstanding their lower specific impulse. The propellant ballistic effectiveness is estimated via the vehicle velocity achieved using the propellant under analysis in a real vehicle. For each specific mission, the binder content can be varied to provide the optimal relationship between energetic and physical-mechanical properties, that is, one may sacrifice energy in favor of rheological and physicomechanical properties (increasing binder mass fraction), or vice versa.