Effects of orientation on the strength of the aluminum alloy 7010-T6 during shock loading: Experiment and simulation

Abstract

The shock response of the aluminum alloy 7010-T6, induced by the technique of plate impact, has been investigated as a function of orientation to the loading axis to the rolling direction. Measurements of the Hugoniot elastic limit (HEL) and spall strength show that the material is stronger in the longitudinal orientation than the short transverse, in keeping with the mechanical properties measured at quasistatic strain rates. Furthermore, a comparison of the HELs to the 0.2% proof stresses suggests that there is a degree of strain-rate sensitivity in the longitudinal orientation, whilst the short transverse appears strain-rate insensitive. Thus, there exists the possibility that strain-rate sensitivity itself is orientation dependent in this alloy. Comparison of the ratios of spall strength according to orientation, to the equivalent quasistatic yield strengths provides further evidence of this hypothesis. A simulation using finite-element modeling has shown that while the model can reproduce the dependency of the HEL on orientation, the degree of success with the spall strength has not been so great.