Fragment mass distribution of metal cased explosive charges

Effects of naturally fragmenting shells are of interest under various circumstances like predicting a weapon's effectiveness or its ability to inflict collateral damage. The effects of fragments may be unintended when shaped charges or blast charges are used to defeat a target. However, for structural reasons these charges are generally equipped with thin metal casings. On the other hand heavier steel casings are used for ammunition when the fragments are the intentional effective defeat mechanism. Fragmentation of metal casings is an important issue in a variety of problems like weapon effectiveness, safety distances or collateral damage. To be able to describe the intended or unintended effects of naturally fragmenting shells, one needs to know the mass distribution of the fragments produced after detonation of the explosive charge. In the present study the fragmentation behavior of very light and heavier casings has been investigated. The data collection method is outlined and applied to the fragment mass distribution of four different shells. The results are given in diagrams. It was found that an existing fragmentation model adequately predicts the dependence of circumferential fragment size on material strength. Fracture in axial direction should also be considered to predict correct fragment masses, but currently a suitable model for this purpose is not available.