Experimental study of reaction properties of aluminum/polytetrafluoroethylene powder under laser ablation

Metal particle size and environment will affect the reaction properties of aluminized polytetrafluoroethylene (Al/PTFE) reactive material. This study experimentally investigated the reaction properties of Al/PTFE with different Al particle sizes through time-resolved self-emitting imaging and emission spectroscopy under nanosecond laser ablation in air and an inert argon environment. The results show that the laser ablation causes a continuous combustion characteristic and a long energy release time in Al/PTFE. Furthermore, the reaction properties of Al/PTFE are closely related to the particle size of Al powder. The emission intensities and durations increase as Al particle size decreases, but it no longer conforms to this rule when Al particle size decreases to nanometers. This inconsistency may be due to the oxidation of Al powder and agglomeration of nano-Al powder. The experiments in different gas environments proved that the reactivity of Al/PTFE in the inert gas environment is not as good as that in air because of the lack of the oxidation reaction between Al and oxygen from the air.