Application of aluminum-based micro-cell composite fuel in HTPB propellant

Abstract

To study the combustion performance of aluminum-based micro-cell composite fuel aluminum@ammonium perchlorate(Al@AP), in hydroxyl-terminated polybutadiene (HTPB) solid propellant, the Al@AP was added to HTPB solid propellant instead of Al powder and part of AP. Firstly, the ignition and energy performance of Al@AP were investigated and the effects of Al@AP on the combustion, process and mechanical properties of HTPB solid propellant were studied by means of sphere explosion test system, adiabatic oxygen bomb calorimeter test, standard test engine test, residual active Al test, viscosity test, and tensile test. In addition, the combustion mechanism of Al@AP in HTPB solid propellant was analyzed. The results indicate that Al@AP composites offer faster ignition response than simple physical blends, and the heat of HTPB solid propellant increases from 7 385 J·g^-1 to 7 834 J·g^-1 when 21.3% Al@AP was used instead of aluminium powder. The amount of residue decreases from 3.88% to 2.10% in mass fraction, the content of active Al in residue decrease from 6.14% to 2.57%, and the particle size d₅₀ of residue decrease from 298 μm to 62 μm. The combustion efficiency of HTPB solid propellant improves from 94.0% to 94.6%. The mechanical and process properties of HTPB propellant containing Al@AP can satisfy the application.

Keywords

Al@AP composite fuel / hydroxyl-terminated polybutadiene (HTPB) solid propellant / combustion performance

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