Approaching the Theoretical Elastic Strain Limit in Copper Nanowires

Three sets of uniaxial tensile tests have been performed in situ in transmission electron microscopy/high-resolution electron microscopy on Cu nanowires (NWs) to accurately map out the sample size dependence of elastic strain limit. Atomic-resolution evidence was obtained for an exceedingly large recoverable strain (as much as 7.2%) that can be sustained in the lattice of a single-crystalline Cu NW with a diameter of similar to 5.8 nm. This ultrahigh elastic strain is consistent with the predictions from molecular dynamics simulations for nanowires and approaches the ideal elastic limit predicted for Cu by ab initio calculations.