Study on HMX/HTPB Propellant With Low Al Powder Content

The formulation of the HMX/HTPB propellant with low Al powder content was studied. In order to obtain the excellent comprehensive performance of reduced smoke, high density, high modulus, high burning rate and low pressure exponent, the formulation was tailored through using mass fraction less than 10% of Al powder and partly replacing AP with HMX to achieve the aim of reduced smoke, through using HTPB/TDI/MAPO/STR binder system to obtain high modulus, and through adjusting AP blend, selecting burning catalysts, and so on to achieve the good performance among which the mass fraction of non-volatile substance is at least 88.5%, the density at 20 ℃ is at least 1.78 g/cm3, the σm is at least 3.1 MPa, the burning rate is at least 40 mm/s, the initial viscosity of the slurry is lower and the flowability and levelling characteristics are well. Through the ground test of BSFΦ127 standard engine,the combustion of HTPB/AP/Al/HMX tetra-component propellant is stable under the internal ballistic p-t curve below 30 MPa. The combustion of the propellant does not sharply rise to lead to the abnormal phenomenon of pressure. It is realized from the ground test of the engine that the mixed specific impulse of the obtained charge grain is up to 2 456.7 N·s/kg.