Ballistic Studies with Intermetallic and Thermite Projectiles in Oxidizing and Inert Environments

A High-velocity Impact-ignition Testing System (HITS) was developed to study the dynamic response of thermite and intermetallic projectiles under high strain impact. Projectiles were launched up to 1300 m/s from a .410 caliber powder gun into test chambers filled with air or argon atmospheres. Projectiles entering the test chambers impacted a steel witness plate after either penetrating a 1.6 mm thick steel plate, penetrating two 3.2 mm thick aluminum plates, or experiencing no penetration. Penetration, impact, and reaction were recorded using two high-speed cameras and pressure transducers captured quasi-static pressure curves. Several key results include the following: intermetallic projectiles produced significantly lower quasi-static pressure in argon environments than thermite projectiles. Across all tests, intermetallic projectiles were less sensitive to ignition than the thermite, however both projectiles generated similar quasi-static pressures at 1300 m/s impact. For both intermetallic and thermite projectiles, when impacting without penetration, reaction mechanisms depend more on the fragmentation behavior than the projectile’s material composition.