Measurement of Mechanical Properties of Explosives

The mechanical properties of explosives control directly their sensitivity due to shock and impact stimuli. The understanding and measurement of these properties are essential for developing insensitive explosives, and in designing hard-target-penetrating munitions. These properties include the strength under high pressure (pressure hardening) and the strength under dynamic loading (strain-rate hardening). Under a recent program support by the HERD at Eglin, we demonstrated the feasibility of a simple method of measuring these critical properties. This method utilizes a copper sleeve to encase the explosive specimen to provide a confining pressure during static or dynamic testing. In static tests, the sleeved specimen is compressed by a standard testing machine. In dynamic test, the sleeved specimen is projected against a stationary anvil, which is equivalent to a reversed Taylor impact test. Preliminary results have shown this method is feasible. In the proposed program, this method will be developed for practical applications.