Experimental study of macro-micro dynamic behaviors of 5A0X aluminum alloys in high velocity deformation

Investigation of macro-micro dynamic mechanical behavior of aluminum alloys is crucial to understand and model high velocity forming processes, e.g. the electromagnetic forming. Therefore, this work presents the experimental investigation of the macro-micro dynamic deformation behavior and related mechanisms of 5A0X alloys. With increasing strain rate, notable hardening and serrated flow curves are observed for both 5A06 and 5A02 alloys; the flow softening ratio increases from 10.59% to 15.56% for 5A06 alloy, while increasing up to 34.55% at a strain rate of 3000 s−1 for 5A02 alloy. High velocity deformation enhances the ductility of both the alloys via slowing down the neck development rather than suspending the onset of necking. Comparative study in dynamic tensile/compressive behavior of 5A06 alloy indicates a similar hardening rule in these two loading conditions, however, more obvious softening is found in tension than that in compression. The difference can be attributed to the different microstructure-related characteristics, namely, the diffuse necking related to void evolution in tension and the adiabatic shear bands (ASB) in compression. In addition, a mathematical model is used in this work to corroborate the occurrence of ASBs and to predict the half width of ASBs, which is proved reliable by experiments.