Abstract
Utilizing a large two-stage light gas gun, 3-cm-diameter spheres were impacted into Al 2024-T351 targets. The fragments were collected from the floor of the impact chamber and were analyzed. In particular, there is interest as to the fragment size distribution and the fragment shape distribution. The fragments were sorted in size, and those from roughly 0.1 g to 35 g were individually tabulated. This allowed the development of a fragment size distribution for these fragments. Then, all the fragments were optically analyzed to provide a quantitative characterization of their shape. The fragments are predominately flat, a shape that appears to correlate with an intersecting shear plane mechanism for the fragment formation in the crater formation. The fragment distribution shows that there are two different fragment formation mechanisms, which it is concluded are due to fragments formed in the interior of the crater entirely of interacting shear planes vs. those whose formation is influenced by the target free surface. The results are compared to other work on fragmentation.
