An experimental study on the impact damage of explosives

Damage not only deteriorates the mechanical properties of explosives, but also influences the sensitivity, combustion and even detonation properties of explosives. The study of formation mechanisms and evolution rule of damage, and the influences of damage on explosives is of great importance for safety evaluation of explosive materials. An experimental study of impact damage in cast Composition B and hot pressed PBXN-5 is presented in this paper. A long-pulse low-velocity gas gun with a gas buffer is used to induce dynamic damage in samples. The projectile velocities and stress history in impact loading are recorded. The microstructure evolution before and after impact are examined by use of Scanning Electronic Microscopy (SEM) and Polarized Light Microscopy (PLM). In addition, the densities and ultrasonic attenuation of undamaged and damaged explosives are measured. The results show that both Composition B and PBXN-5 exhibit brittle damage characteristics. However, due to the difference in compositions, PBXN-5 exhibits better resistance to dynamic loading than Composition B.