Cyclic deformation induced strengthening and unusual rate sensitivity in Cu/Ru nanolayered films

In this work, we have systematically investigated the effect of cyclic deformation on the strength and rate sensitivity of Cu/Ru multilayers with different individual layer thickness (h) by nanoindentation tests. It was found that cyclic deformation remarkably enhances the hardness of Cu/Ru multilayers comparing with the specimens by monotonic loading. The rate sensitivity (m) of multilayer exhibits an anomalous size dependence after nanoscale...