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The response of an epoxy resin has been investigated using the methods of plate impact to generate planar shock waves. In particular, the Hugoniot, both in stress–particle velocity and shock velocity–particle velocity space, and the variation of shear strength with impact stress, have been investigated. Comparison of the results of this investigation with those of previous workers shows good agreement. Measurements of lateral stress, which have been used to determine the shear strength have indicated that shear strength increases with longitudinal stress in the range investigated. Further, lateral stresses have been shown to decrease behind the shock front, implying an increase of strength of this material during shock loading. It would seem possible that this is a manifestation of the viscoplastic nature of epoxy based resins.

Lateral stresses generated by shock loading in tantalum have been determined using manganin stress gauges. These have been used in combination with the measured longitudinal impact stresses to determine the shear strength behind the shock. Results show that with an increase in impact stress, the shear strength in tantalum also increases. Analysis shows that during shock loading the lateral stress in tantalum increases behind the shock front. Since the longitudinal stress is nominally constant until arrival of the release, this implies that the shear strength is reducing behind the shock front. The shock-wave response of tantalum is discussed in the context of a previous weak-shock wave-profile analysis of tantalum, and in terms of the defect generation and storage response of pure face-centered- versus body-centered-cubic metals.