The mechanism of instability and localized reaction in the explosively driven collapse of thick walled Ni-Al laminate cylinders

Thick-walled cylinders constructed from alternating concentric layers of Ni and Al foils were explosively collapsed. The prevalent mode of the high strain, high strain rate plastic deformation was the cooperative buckling of the foils originating in the interior layers. This phenomenon was reproduced in numerical simulations. Its mechanism is qualitatively different than that of shear localization seen in all previously investigated homogeneous solid and granular materials and from the independent buckling of single thin-walled cylinders. Localized chemical reactions were observed in the apex areas of the Ni foils, consistent with the localization of temperature due to high strain plastic deformation.