Al/Ti 基纳米复合燃料热反应性及燃烧性能

To effectively promote the intermetallic reaction between Al and Ti, two types of core-shell structured nanocomposite fuels have been prepared by using the high-energy ball milling method, namely Al/Ti@ AP/NC and Al/Ti@ PVDF/CL-20. The quality of the coating layers of AP/NC and PVDF/CL-20 on the surface of Al/Ti is inspected by scanning electron microscopy (SEM). The thermal reactivity, heat of reaction and combustion performances of Al/Ti-based composite fuels are evaluated by DSC/TG thermal analyses, a bomb calorimeter, and a customized combustion diagnostic system. The morphologies and compositions of the condensed combustion products (CCPs) are characterized by SEM and X-ray diffraction (XRD) techniques, respectively. Results show that the core-shell structured Al/Ti@AP/NC and Al/Ti@PVDF/CL-20 could be obtained by high-energy ball milling method. The thermal decomposition of the energetic composites is enhanced with the introduction of Al/Ti. Furthermore, the intermetallic reaction between Al and Ti, burning rate, and the combustion wave temperature could be enhanced with the inclusions of AP/NC or PVDF/CL-20. In particular, for the composite fuel coated with AP/NC, the burning rate (246.6 mm·s ^-1) is increased by 9.5 times and the combustion wave temperature (1 703.2 ℃) is 59.3% higher compared to that of pure Al/Ti (the burning rate and combustion wave temperature are 23.5 mm·s ^-1 and 1 069.3 ℃, respectively). The compositions of the CCPs depend on the types of energetic coating layers, which are dominated with AlTi₂ C and Ti(O_0.19 C_0.53 N_0.32), indicating that chemical reactions occur between Al/Ti and energetic composites during the combustion process.