Unraveling the effects of interface orientation and crystallography on the deformation mechanisms of accumulative roll-bonded Cu-Nb-multilayered nanocomposites using molecular dynamics.

Abstract

This work elucidates the effect of interface orientation, loading mode, and crystallography on the deformation mechanisms of Cu-Nb-multilayered nanocomposites. Molecular dynamics simulations of deformation behavior of accumulative roll-bonded Cu-Nb-multilayered nanocomposites (MNCs) were performed at room temperature conditions and at a constant strain rate under iso-stress and iso-strain conditions. Interface deformation mechanisms involving nucleation of partial dislocation at the interface and gliding in the Cu layer were observed under iso-stress and iso-strain conditions. Uniaxial stress-strain curves were analyzed for tension and compression under iso-stress and iso-strain loading conditions. The stress-strain plots were explored to understand the elastic, yield, and post-yielding behavior of Cu-Nb MNCs. Under compression with interface orientation normal to the loading direction, twin nucleated via gliding of partial dislocations. Under tension in the iso-stress case, only slip-assisted deformation was observed. Conversely, the deformation behavior under compression and tension was via slip and twinning, respectively, for iso-strain conditions.