Characterizing the fragmentation ring on witness plates

Hole-saw ring patterns on the witness plate are studied systematically. Aluminum alloy 1100 and 6061, inconel, teflon, and lead of different thicknesses were utilized for target material. The ring patterns are observed at D(sub p)/T = 1.98 to 4.02 for aluminum 1100 target, at D(sub p)/T = 1.55 to 10.51 for aluminum 6061 target, at D(sub p)/T = 4.41 to 9 98 for inconel target, at D(sub p)/T = 1.33 to 3.94 for teflon target, and at D(subp)/T = 12.5 to 20.89 for lead target. The ring diameter showed a decreasing trend when D(sub p)/T ratio increased. An analytical model is introduced. The crater distributions on the ring were investigated. The majority of the craters are in the neighborhood of 1100 micrometers to 1400 micrometers size. Many broken string like craters were observed on the ring as well as inside the ring.