Influence of the Density of PETN–Coal Composites on the Threshold Characteristics of Explosive Decomposition in Laser Initiation

• Published in: Combustion, explosion, and shock waves explosion, and shock waves, 2020-03, Vol.56 (2), p.231-236
• Main Authors: Aduev, B. P., Nurmukhametov, D. R., Belokurov, G. M., Kraft, Ya. V., Ismagilov, Z. R.
• Format: Article
• Language: English
• Subjects: Classical and Continuum Physics; Classical Mechanics; Composite materials; Control; Decomposition; Density; Dynamical Systems; Engineering; Inclusions; Lignite; PETN; Physical Chemistry; Physics; Physics and Astronomy; Shock waves; Vibration
• ISSN: 0010-5082; 1573-8345
• DOI: 10.1134/S0010508220020148

This paper presents the results of measuring the thresholds of explosive decomposition of PETN–coal under the action of laser radiation pulses ( λ  = 1064 nm and τ  = 14 ns). Samples whose thickness is 1 mm and whose densities are 1.1 and 1.7 g/cm 3 with inclusions of submicron particles of brown coal (750 nm) are investigated. Matrices in composites with densities of 1.1 and 1.7 g/cm 3 are almost transparent for radiation. A minimum explosive threshold of 1.8 J/cm 2 is reached with a concentration of inclusions of 0.5% (by weight). The explosion is adiabatic. Composites with a density of 1.1 g/cm 3 have a scattering matrix. A minimum explosive threshold of 2.3 J/cm 2 is obtained for a concentration of inclusions of 1%. An extinction rate is estimated:  = 135 cm - 1 . Radiation is absorbed at a depth of < 0.1 mm. Explosive decomposition in an unirradiated section develops according to the shock-wave mechanism of explosive combustion.