Size effect and interfacial strength in nanolaminated Cu/CuxTa100-x composites using molecular dynamics

[Display omitted] •Stacking faults are formed and the 〈112〉 dislocation occurs in the Cu layers.•The FCC structures are mainly transformed into the HCP structures in the Cu layers.•The ESBs are generated at the intersections of interfaces and stacking faults.•The tensile strength presents an agreement with the H-P relation as w1 reduces.•The Cu/Cu60Ta40 shows the best, while the Cu/Cu40Ta60 shows the least plasticity. In this study, molecular dynamics method is used to investigate the plastic deformation phenomena and the mechanical properties of the crystalline/amorphous Cu/CuxTa100-x nanomultilayers (CANMs) through the tension process. The effects of the layer numbers, layer width, components percentages, and cooling rate (CR) in the Cu-Ta metallic glasses (MGs) of the Cu/CuxTa100-x CANMs are considered. The results exposethat in all cases, the deformation occurring in the Cu layers is more catastrophic than that in the Cu-Ta MGs layers. The embryonic shear bands (ESBs) are primarily generated at the intersections between the interfaces and stacking faults, then develop and expand within the Cu-Ta MGs layers to form the shear transformation zones (STZs). The constriction initiations appear at the junctions of the free surfaces and the interfaces in adjacent layers. For the Cu/CuxTa100-x CANMs with different layer numbers, the wider Cu layer better restricts the shear bands (SBs) propagation in the Cu-Ta MGs layers. Moreover, the tensile strength presents an agreement with the Hall-Petch relationship as the layer number reduces. For the cases of the various layer widths, the plastic deformation increases with the decrease in the width of the Cu-Ta MGs layers (w1). The tensile strength shows an agreement with the inverse Hall-Petch relationship as the w1 reduces. For the cases of the various component percentages in the Cu-Ta MGs layers, the Cu/Cu60Ta40 CANMs provides the best plasticity while the Cu/Cu40Ta60 CANMs supplies the least plasticity. The tensile strength is higher with the larger Ta component percentages in the Cu-Ta MGs layers. The structure of the Cu50Ta50 MGs is more stable, leading to the tensile strength of the Cu/Cu50Ta50 CANMs increases as the cooling rate decreases.