Tuning energy output of PTFE/Al composite materials through gradient structure

As a typical energetic composite, polytetrafluoroethylene (PTFE)/aluminum (Al) has been widely applied in explosives, pyrotechnics, and propellants due to its ultra-high energy density and intense exothermic reaction. In this work, the radial gradient (RG) structure of PTFE/Al cylinders with three different PTFE morphologies (200 nm and 5 μm particles and 5 μm fiber) and content changes are prepared by 3D printing technology. The effect of radial gradient structure on the pressure output of PTFE/Al has been studied. Compared with the morphology change of PTFE, the change of component content in the gradient structure has an obvious effect on the pressure output of the PTFE/Al cylinder. Furthermore, the relationships of the morphology, content of PTFE and the combustion reaction of the PTFE/Al cylinder reveal that the cylinder shows a more complex flame propagation process than others. These results could provide a strategy to improve the combustion and pressure output of PTFE/Al.