Experimental Investigation of Reaction-Induced Pressure Perturbations in PTFE/Al Composites During Shock Compression

In this study, reaction mechanisms of polytetrafluoroethylene/Al materials under shock compression were investigated. The reaction-induced pressure perturbations in PTFE/Al materials were identified by comparing pressure profiles with those of inert PTFE/LiF counterparts. The pressure rebounded to a range of 10.2-16.9 GPa under an incident shock pressure range of 11.5-22.6 GPa. The pressure perturbation amplitude induced by reaction gradually attenuated with increasing propagation distance. The delay time between the observed pressure perturbations and the incident shock front arrival ranged from 0.84 to 1.71 μs and showed a decreasing trend with increasing incident shock pressure and decreasing aluminum particle size. The results suggest that the reaction ignition and energy release of PTFE/Al materials change from closely following the shock front to being delayed by hundreds of microseconds behind the shock front when shock compression intensity decreases from GPa to MPa levels.