Preparation of spherical Al-Ti alloy powder and investigation of its ignition and combustion characteristics

This study investigates the combustion properties of aluminum-titanium (AlTi55) alloy powder as a promising alternative metal fuel that addresses the shortcomings of traditional titanium (Ti)-based ignition powders. The AlTi55 alloy, prepared using high-speed dish spherical centrifugal atomization with a mass ratio of 45 wt% Al to 55 wt% Ti, underwent systematic analyses of its physicochemical characteristics, calorific value, and thermal oxidation kinetics. The results show that the calorific value of AlTi55 is 21.78 kJ/g, surpassing Ti's value of 19.86 kJ/g by 1.92 kJ/g. The Kissinger activation energy for AlTi55 is 146.78 kJ/mol, lower than Ti's 150.23 kJ/mol, indicating superior thermal stability. Kinetic combustion analysis demonstrated that, when tested with ammonium perchlorate (AP), potassium perchlorate (KP), and copper oxide (CuO), AlTi55 exhibits longer ignition delay times and sustained combustion, reflecting enhanced oxidative resistance. The oxidation resistance of AlTi55 is intermediate between Al and Ti, alleviating ignition delay while avoiding Ti's oxidation inefficiencies. Laser particle size analysis revealed a median diameter (D₅₀) of 35.21 µm, along with a uniform distribution suitable for practical applications. The primary phase is a single γ-AlTi, consistent with the binary phase diagram. Notably, AlTi55’s ignition temperature (1548.57 K) exceeds Ti's (1154.64 K), confirming its stability at high temperatures. The findings indicate that AlTi55 not only mitigates ignition delays and enhances energy release stability but also presents significant potential for future applications in ignition powders. This research contributes valuable insights to the field of Al-Ti alloy fuels.