Assessment of the terminal velocity of explosively-propelled metal liner using laser-induced breakdown spectroscopy

Organic energetic compounds containing aluminum (OECAl) are hazardous materials, which have extensive applications in industries. For military and commercial high explosives, Gurney velocity is the terminal velocity of explosively-propelled metal liner on the bases of the ratio of the mass of metal to the mass of explosive. Due to the high cost of experimental determination of Gurney velocity, it is suitable to have a low-cost experimental method for reliable estimation of Gurney velocity of OECAl. A novel approach is introduced to use laser-induced breakdown spectroscopy (LIBS) as a highly energetic laser pulse to atomize and excite samples (a plasma) for assessment of the Gurney velocity of OECAl. Five compositions of 1,3,5-trinitro-1,3,5-triazine (RDX)-based aluminized explosives are studied through the LIBS technique to detect their atomic and molecular emissions in the air atmosphere. Plasma emissions of these compositions are recorded where the atomic line of Al as well as molecular bands of AlO and CN have the highest intensities at some wavelengths. Intensities of Al (lambda = 394.38 and 396.16 nm), CN (lambda = 388.29 and 422.70 nm), and AlO (lambda = 467.19, 484.25, and 464.84 nm) peaks are correlated with their Gurney velocities. The intensity of Al at 396.16 nm gives the best linear relationship (r(2) = 0.981) with the Gurney velocity of OECAl samples.