The Deviatoric Response of an Epoxy Resin to One-Dimensional Shock Loading

Abstract

In a previous paper, it was shown that an experiment might be designed to simultaneously measure the stress‐particle velocity and the shock velocity‐particle velocity properties of an impacted solid. It was shown that in an epoxy, the Hugoniot and the hydrostat diverged which was suggested might be due to variations in shear strength with increasing longitudinal stress. In this paper, this issue is investigated further by embedding manganin stress gauges in such orientation that they are sensitive to the lateral component of the stress during the one‐dimensional shock loading. From measured lateral and known longitudinal stresses, shear strengths are calculated. Results show that this increases with increasing shock stress amplitude. It has also been noticed that behind the shock front at higher stresses, there is a significant decrease in lateral stress. Such behaviour has been observed before in polymethylmethacrylate where it was suggested that this was due to the viscoeleastic/plastic nature of the material. It would thus seem likely that epoxy resins behave in a similar fashion.