Effect of strain rate on the ductility of a nanostructured aluminum alloy

Nanostructured materials normally exhibit enhanced ductility at higher strain rate. In this paper we report the observation that a cryomilled nanostructured 5083 Al alloy exhibits the opposite behavior, i.e., higher ductility at lower strain rates. This phenomenon was rationalized by a diffusion-mediated stress relaxation mechanism that effectively delayed crack initiation events.