The variation in lateral and longitudinal stress gauge response within an RTM 6 epoxy resin under one-dimensional shock loading

Abstract

The dynamic response of a commercially important epoxy resin (RTM 6) has been studied using plate impact experiments in the impact velocity regime of 80-960 m/s. Both longitudinal and lateral manganin stress gauges were employed to study the development of orthogonal components of stress both during and after shock arrival. In light of recent work raising doubts about the interpretation of lateral gauge data, lateral response within the RTM 6 resin was also used to investigate the physical phenomena being measured by the embedded lateral gauges. U S -u P and σ X -u P Hugoniot relationships were in good agreement with data for similar polymer materials from the literature. Derivation of shear strength behaviour both during and after shock arrival showed evidence of strengthening behind the shock front, attributed to compression of the cross-linked epoxy resin polymer chains. Comparison of the change in lateral stress behind the shock to the behaviour of an epoxy resin possessing a similar U S -u P Hugoniot from the literature showed a different response; likely attributable to enhanced cross-linking present in this second resin. This result suggests that the embedded lateral gauges were, at least in part, measuring a physical response behind the shock within the resin. A Hugoniot elastic limit of 0.88 ± 0.04 GPa was derived and found to be of the same order of magnitude as results found elsewhere for similar materials.

A study on the strength of an armour-grade aluminum under high strain-rate loading

“…In this case, however, the observed plateaus and subsequent gradients in lateral stress had significantly shorter durations than those observed by Millett et al, 4 fully damp-out, suggests a gauge response. 4,13,15,24,25 Winter and Harris 22 and Winter et al 23 employed a combination of simulation and experiment to investigate the propagation of shocks through both a so-called matrix material and a matrix material with an embedded fluid layer ͑analogous to an encapsulated gauge͒. 8; the relatively lazy rise time on this gauge appears to have smoothedout any initial effects.…”

“…8; the relatively lazy rise time on this gauge appears to have smoothedout any initial effects. While a significant body of work suggesting that lateral gauges do record material phenomena behind the shock exists in the literature, 4,13,15,24,25 it is clear from Winter and Harris 22 and Winter et al 23 that substantial doubt as to the validity of this approach remains. 4,13,15,24,25 Winter and Harris 22 and Winter et al 23 employed a combination of simulation and experiment to investigate the propagation of shocks through both a so-called matrix material and a matrix material with an embedded fluid layer ͑analogous to an encapsulated gauge͒.…”

Investigation of the high-strain rate (shock and ballistic) response of the elastomeric tissue simulant Perma-Gel®

“…4/ Table 3. While elsewhere such behaviour has been tentatively linked to steric-based strengthening effects behind the shock [33,36,37], here further observation suggests that the deviation is in fact relatively insignificant. In Fig.…”

Molecular dynamics simulations of shock waves in cis-1,4-polybutadiene melts

“…While there are many experimental (e.g., Refs. [15][16][17][18][19][20][21][22] and computational engineering (e.g., Refs. [23][24][25][26][27] studies of polymers and polymer-based composites subjected to shock wave excitation, there are relatively few atomic-level computational studies, [28][29][30][31][32][33][34][35][36] which is understandable given the complexities of polymeric materials and the relatively large spatial and temporal scales over which post-shock relaxation in them occurs.…”