Laser-Induced Combustion and Shock Wave Expansion Dynamics of Energetic Metal Particles

Laser-induced Air Shock from Energetic Materials (LASEM) is an experimental technique utilized for characterizing the reactive behavior of energetic materials on a laboratory scale. It presents a cost-effective and efficient alternative to full-scale detonation testing, as it requires significantly lesser quantities of fuel (in the order of milligrams) compared to large-scale detonation experiments, which demand several hundred grams to kilograms of energetic materials/fuels.

To conduct LASEM experiments, we employ a high-pressure, optically accessible, custom-built constant volume vessel. A nanosecond-pulsed laser with a pulse width of 6 ns and a wavelength of 1064 nm is focused on a glass slide uniformly coated with metal nanoparticles, namely nano-aluminum, nano-titanium, and micro-magnesium. High-speed filtered imaging is employed to study the laser-induced shock dynamics and combustion processes of these metal nanoparticles. The propagation speed of the laser-induced shock wave is recorded using high-speed Schlieren imaging at a frame rate of million frames per second. Additionally, the air is replaced with argon to isolate the shock dynamics from the combustion processes.

Preliminary findings from the literature indicate a promising correlation between laser-induced shock velocity and the detonation velocities of traditional explosives such as TNT, RDX, HMX, and CL20. By extending LASEM to characterize metal nanoparticles, this study aims to contribute valuable insights into the energetic behavior of these materials. Understanding the shock dynamics and combustion processes of metal-based propellants is crucial for various applications, including propulsion systems and pyrotechnics.