Blasting fragmentation of spherical shells under internal explosion loading

Experimental data on the fragmentation, scattering, and penetration into barriers of fragments of thin-walled spherical shells made of soft steel or an aluminum alloy, which are loaded internally by blasting a sphere-shaped explosive charge, are presented. The speeds, number, and average sizes of fragments formed of shells of different sizes as well as the maximum depths of penetration of fragments into barriers made of a number of homogeneous and heterogeneous materials have been determined. Some peculiarities of the fragmentation of spherical shells under internal blast loading have been elucidated. An attempt has been made to describe the characteristic (average) fragment size by a formula derived from the balance of elastic energy and the work of fracture. Thicknesses of fragmentation protective layers of some structural materials have been chosen, which enable catching fragments of soft steel or an aluminum alloy which are formed by the explosion of particular sphere-shaped explosive charges.