Drop Hammer Impact Ignition Experiment and Effect of Additives on Energy Release Characteristics of PTFE-Based Reactive Materials

To solve the problem of low energy release efficiency of fluoropolymer-based reactive materials, four PTFE (Polytetrafluoroethylene) -based reactive structural materials with different contents were prepared by adding traditional energetic materials (RDX, 1,3,5-Trinitrohexahydro-1,3,5-triazine) and alloy metals (aluminum magnesium, aluminum magnesium zinc). In addition, in order to reduce the high cost of the existing high-speed impact energy release testing device, the formulation optimization of PTFE-based aluminum alloy reactive material was efficiently carried out using a small-scale drop hammer impact test in this paper. The self-designed impact energy release testing device was established for the overpressure measurement of PTFE-based aluminum alloy reactive materials. The impact response processes of PTFE-based aluminum alloy reactive material were recorded with high-speed photography. The energy release characteristics were quantified using overpressure measurements. Based on the chemical reaction properties and microstructural characterization of the PTFE-based reactive materials, the ignition mechanism of aluminum alloy reactive materials was analyzed under drop hammer impact load. The results show that the quantitative characterization of the overpressure changes of reactive materials in a quasi-enclosed space before and after reaction can reflect their energy release efficiency under low-velocity impact by using the drop hammer impact energy release testing device. The order of impact response overpressure values for four PTFE-based reactive materials has been conducted. The aluminum alloy reactive material containing RDX explosive has the highest overpressure value and the highest energy release efficiency in terms of drop hammer impact response. Based on the ignition mechanism and energy release characteristics of these four PTFE-based reactive materials, it was found that the addition of alloy metal powder can reduce impact sensitivity, but when activated, it can effectively enhance the damage effect.