Properties of ejecta generated at high-velocity perforation of thin bumpers made from different constructional materials

The series of impact experiments were performed to study the properties of ejecta generated at high-velocity perforation of thin bumpers. The bumpers were aluminum plates, fiber–glass plastic plates, and meshes weaved of steel wire. The projectiles were 6.35 mm diameter aluminum spheres (and 3.2 mm diameter aluminum spheres only for several experiments with fiber–glass plastic). The impact velocities ranged from 1.95 to 3.52 km/s. In the experiments the ejecta particles were captured with low-density foam collectors or registered with the use of aluminum foils. The processing of the experimental results allowed us to estimate the total masses, spatial and size distributions, and perforating abilities of the ejecta produced from these different bumpers. As applied to the problem of reducing the near-Earth space pollution caused by the ejecta, the results obtained argue against the use of aluminum plates as first (outer) bumper in spacecraft shield protection.