A molecular dynamics investigation into deformation mechanism of nanotwinned Cu/high entropy alloy FeCoCrNi nanolaminates

High-entropy alloys (HEA) present high hardness, but low tensile ductility. Here, deformation behaviour of the nanotwinned Cu/HEA FeCoCrNi nanolaminates prepared by the previous experiment is investigated using atomic simulations. The result shows the nucleation and glide of lattice dislocations in the Cu layers dominate the initial plastic deformation in Cu/HEA multilayers, and these gliding dislocations are deposited at the twinning boundary. With the increasing strain, the dislocations are activated in HEA layer, and deposited in the Cu-HEA interface, finally facilitate slip transmission from the HEA layer to the Cu layer. The flow stress decreases and keeps a constant value with increasing nanotwinned Cu/HEA FeCoCrNi layer number, which depends upon the slip transmission and interfacial dislocation to govern strain hardening.