Ultra-fast response behavior of aluminum hydride (AlH₃) in a quasi-detonation environment

Aluminum hydride (AlH₃), as a potential new metal fuel, has attracted extensive attention in the field of hydrogen storage materials, propellants and energetic materials due to its excellent properties. In this paper, a new organic liquid phase reduction method was used to prepare AlH₃, and the microstructure and composition of the prepared samples were characterized by SEM–EDS, XRD, FT-IR, XPS, etc. The main crystal phase of the prepared AlH₃ was α-AlH₃, with high quality and no other impurities. The thermal decomposition behavior and non-isothermal reaction kinetics of AlH₃ were investigated by TG-DSC. The results show that there are three exothermic stages in the heating process of AlH₃: dehydrogenation of AlH₃, first oxidation of Al, and second oxidation of Al. The activation energy of the dehydrogenation of AlH₃ is 77.8675 kJ/mol (Kissinger method) and 81.4862 kJ/mol (Ozawa method), respectively. The morphology evolution of AlH₃ particles during the heating process (300–3000 K) was simulated using a reaction kinetics method based on the ReaxFF force field. The response behavior of AlH₃ in the instantaneous high-temperature detonation environment was investigated using the high-energy laser-induced shock wave technique. Under the impact of a high-energy laser (1006 mJ), the AlH₃ sample undergoes an ultra-fast reaction and generates a large amount of plasma. The expansion of the plasma pushes the surrounding air to form a supersonic shock wave and propagates forward. The shock wave propagation velocity of AlH₃ is 690.99 m/s in the range of 2.1–12.35 μs, and the higher the laser energy, the faster the shock wave propagation velocity. This study provides the basis for the application of AlH₃. Graphical Abstract: [Figure not available: see fulltext.].