Structural and combustion characteristics of samples prepared by electrostatic spraying and physical mixing: a comparative analysis of Al with CuF₂/CuO and PVDF

Nanocomposite thermite materials show great application potential in high-energy-consuming applications. However, significant challenges remain in precisely controlling their nanoscale microstructure and synergistically optimizing their combustion performance. Building upon the high oxidative potential of metal fluorides, using electrostatic spray technology, composite thermite particles were prepared with metal fluoride (CuF₂) and metal oxide (CuO) as oxidizers and polyvinylidene fluoride (PVDF) as a binder. Comparative samples were prepared by physical mixing. With the help of transmission electron microscope (TEM), scanning electron microscope (SEM), energy-dispersive spectrometer (EDS), X-ray diffractometer (XRD), simultaneous thermogravimetry–differential scanning calorimeter (TG-DSC), and combustion performance test system, the microstructure, thermal reaction kinetic traits, combustion performance parameters, energy release law, as well as the morphological traits and component structure of combustion products of the prepared composite materials were systematically characterized and analyzed. The research results show that, compared with physically mixed samples, the composite materials prepared by electrostatic spray form submicron-scale (nano-aluminum powder) and micron-scale structures (micron-aluminum powder) with uniformly dispersed reactants in a nearly spherical shape. This structure enhances interfacial contact, suppresses nanoparticle agglomeration, and promotes more efficient energy release and combustion heat utilization. These samples exhibit larger flame height and area, higher combustion temperature and produce condensed-phase products with a fragmented, porous morphology and fewer metallic residues, indicating more complete reactions. Notably, CuF₂-containing thermites demonstrate significantly higher combustion intensity than conventional thermite formulations. In conclusion, developing high-performance fluorine-containing thermite materials holds considerable academic and practical value for advancing thermite technology.