The deformation behavior of nanostructured metallic multilayers has been extensively investigated because of their superior mechanical properties, primarily via nanoindentation and micropillar compression experiments. Here, we report tensile measurements on a Cu/Co nanolaminate with 4 nm layer spacing. The nanolaminate was synthesized using magnetron sputtering at room temperature and tensile loading-unloading cycles were performed on freestanding samples parallel to the Cu/Co interface using MEMS devices. Cross-sectional TEM and XRD measurements showed the presence of a coherent Cu/Co interface. The nanolaminates exhibit a flow strength as high as 2 GPa and failure strains of 3-4%. Interestingly, significant inelastic strain recovery was observed both during and after unloading, with further recovery occurring upon heating. In addition, the stress-strain slope during the initial stages of unloading was considerably higher than the expected elastic modulus, suggesting the presence of a super modulus effect due to the large coherency strain.
5:00 PM–7:00 PM Apr 23, 2019 (US - Arizona)
PCC North, 300 Level, Exhibit Hall C-E