Enhanced stability and combustion performance of AlH3 in combination with commonly used oxidizers.

[Display omitted] • Homogeneous composites have been obtained by in-situ recrystallization method. • Stability of AlH 3 and reactivity of oxidizers in composites are both improved. • VST results indicate the involved mixture systems are all compatible. • Composites have higher flame radiation intensity and shorter ignition delay time. Aluminum hydride (AlH 3), as a promising fuel, has been utilized to improve the energy performance of propellants. Moreover, the inherent compatibility and mutual interaction between AlH 3 and the commonly used oxidizers of solid propellants are the basics of propellant formulation design. Herein, the homogenous composites of AlH 3 /oxidizer have been prepared by the in-situ recrystallization method, and then their thermal stability, compatibility, and ignition performance have been investigated. The initial decomposition temperatures (T i) of AlH 3 in composites are increased by at least 16 °C, whereas the thermal decomposition peak temperatures (T p) of involved oxidizers are lower than that of their pure state. The compatibility tests showed that AlH 3 is compatible with the mentioned oxidizers. In particular, the induction time of the dehydrogenation of AlH 3 in presence of these oxidizers is improved by almost 1.2 times that of raw AlH 3 , which means that the oxidizers have an unexpected strong stabilization effect on AlH 3 due to strong hydrogen bonding. Moreover, the optimized contents of AlH 3 in AlH 3 /HMX, AlH 3 /CL-20, and AlH 3 /AP composites have been determined to be 45 %, 40 %, and 33 %, which have the maximum flame temperatures of 1275.3, 1440.4, and 1616.8 °C, respectively. Besides, AlH 3 /CL-20 has the strongest flame radiation intensity (18.5 K) and shortest ignition delay time (32.2 ms) among the involved composites. [ABSTRACT FROM AUTHOR]