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The combustion of metastable intermixed composites (MICs) containing fluoropolymers is yet still not well understood. In this study, five new Al/MO X /PVDF nanocomposites (MO X : WO 2 , WO 3 , CuO, Fe 2 O 3 , Bi 2 O 3) are prepared using a high-energy ball milling method. The thermal decomposition behaviors, combustion characteristics, and combustion products of the MICs are compared using TG-DSC, laser ignition test, and a multifunctional combustion diagnostic system. It is proved that PVDF efficiently promotes the energy release of conventional thermites. All five composites show a higher heat of reaction than Al/MO X in an argon environment by over 30%. Al/WO 3 /PVDF has the fastest combustion propagation speed in the confined combustor (72.5 mm⋅s−1). Due to the low boiling temperature and low thermal conductivity of the product, Al/Bi 2 O 3 /PVDF exhibits the lowest ignition delay (62 ms), the best pressure output performance (27.5 MPa⋅s−1), and the least product agglomeration (D 43 = 15.2 μm). Due to the highest heat of reaction (3829 J⋅g−1), Al/CuO/PVDF has the highest flame temperature (2544 °C). The combustion flame temperature of Al/MO X /PVDF nanocomposites is suggested to be controlled by the heat of reaction, the ignition delay is mainly controlled by the thermal conductivity of the material, and the main factor affecting the high pressure output is the boiling point of the combustion products. This study can provide a theoretical basis for the development and application of MICs. [ABSTRACT FROM AUTHOR]

The ignition and combustion characteristics of kerosene fuels containing polydopamine (PDA)-coated metastable intermixed composite (MIC) nano-aluminum (n-Al)/nano-copper oxide (CuO) are experimentally investigated, with a focus on the mass content of CuO in n-Al@PDA@CuO MICs. The total heat release of n-Al@PDA@CuO (2%) is found to be higher than that of the other n-Al@PDA@CuO samples. During the combustion of n-Al@PDA@CuO (2% and 5%)/kerosene droplets, a yellow flame appears around the agglomerate, which eventually evolves into a yellow light sphere with a diameter of around 5 mm after the kerosene flame extinguishes. Examination of the normalized droplet diameter curves and the morphology of combustion residues shows that the n-Al@PDA@CuO (2%)/kerosene droplet has the best all-around combustion characteristics. A mechanism is proposed for the enhancement of kerosene combustion by n-Al@PDA@CuO. Supporting data from thermogravimetry and differential scanning calorimetry (TG-DSC) measurements are presented. The findings and data in this study are expected to advance the development of new kerosene-based nanofluid fuels that meet the high energy demands of liquid propulsion systems. [ABSTRACT FROM AUTHOR]