Probing the difference in improving the ignition and combustion of micro/nano-sized aluminum powder modified by VitonA

Aluminum (Al) powder is commonly used in solid propellants because of its high energy density. However, Al powder is prone to agglomeration during combustion, resulting in lower combustion efficiency. The energy-containing composites of micro/nano-sized Al powder modified by the hexafluoropropylene and vinylidene fluoride dipolymers (VitonA) were fabricated by an evaporation solvent method, and the morphology, thermal behavior, and ignition and combustion (IAC) properties were investigated. The IAC performance of the nano-sized aluminum (nAl) is improved obviously when the coating concentration of VitonA reaches 15%, and higher combustion intensity is attained, which confirms the occurrence of the preignition reaction between nAl and fluoropolymer. Although the IAC properties of micro-sized Al (μAl) powder are also improved by VitonA, there is different impact mechanism of VitonA on the nAl and μAl. These results provide guidance for inhibiting the agglomeration of Al powder and improving its combustion efficiency.