Molecular dynamics study of deformation behavior of crystalline Cu/amorphous Cu 50 Zr 50 nanolaminates

Molecular Dynamics Study of the Nanoindentation Behavior of Cu64Zr36/Cu Amorphous/Crystalline Nanolaminate Composites

“…With further penetration of the amorphous layer, larger plastic zones formed around the indenter, but there was no nucleation of dislocations or stacking faults up to an indentation depth of 45 Å. Hence, none of these plastic zones were a potential origin of dislocation nucleation in the crystalline layer, as previously reported in the literature [ 32 , 33 , 34 , 35 ]. One reason for that could be that in our case, no dominant shear band forms; thus, the local stress fluctuations were too small to generate dislocation slip.…”

“…The system sizes in the directions perpendicular to the indentation direction were chosen to be large enough to avoid spurious effects of the PBC. In the present MD simulations, the modified Finnis–Sinclair-type potential for Cu–Zr binary alloys proposed by Mendelev et al [ 39 ] were used, which had previously been successfully applied to simulate the deformation behaviors of Cu–Zr MGs and their composites [ 25 , 35 , 36 , 37 , 40 ]. The atoms in the indenter were kept fixed (i.e., the indenter was assumed to be an infinitely rigid body).…”

“…Incorporating crystalline phases mitigates the poor failure resistance in MGs, which accommodates plastic strain by dislocation slip, effectively preventing shear band propagation [ 4 , 5 , 6 , 27 , 28 , 29 ]. More recent simulation studies have confirmed that the crystalline phase inserted into the amorphous phase can impede the propagation of SBs, and plays a vital role in the plastic deformation mechanism of ACNLs [ 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 ]. Furthermore, these studies also provide insight into how the microstructure, layer thickness and individual phase properties can be tailored to optimize the mechanical properties of the composites [ 35 , 36 , 37 , 38 ].…”

“…More recent simulation studies have confirmed that the crystalline phase inserted into the amorphous phase can impede the propagation of SBs, and plays a vital role in the plastic deformation mechanism of ACNLs [ 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 ]. Furthermore, these studies also provide insight into how the microstructure, layer thickness and individual phase properties can be tailored to optimize the mechanical properties of the composites [ 35 , 36 , 37 , 38 ]. Although atomic simulation of the nanoindentation behavior and the influence of different factors on mechanical properties have been considered comprehensively, the change of the local stress distribution from the amorphous layer to the crystalline layer and the deformation behavior during the unloading process were not discussed yet.…”

Molecular dynamics study of strengthening mechanism of nanolaminated graphene/Cu composites under compression

“…There is no dislocation reaction happening before point α, so the delayed dislocation nucleation should be attributed to the loading-bearing effect of the incorporated graphene. As ROM can be applied to describe the yield stress 32 , 57 , we used the ROM* taking the GAZ into account to fit the dislocation nucleation stress in Fig. 6(c) .…”