Mechanical Properties of Cold-Welded CoCrFeCuNi Nanowires with Side-by-Side Contact: A Molecular Dynamics Study

Cold welding at the nanoscale is a promising technique for bottom-up fabrication and assembly of nanostructured materials. Herein, the cold welding process of the CoCrFeCuNi high-entropy-alloy (HEA) nanowires in the form of side-by-side contact using molecular dynamics simulation is inestigated. The effects of overlap length, crystal orientation, and temperature are taken into consideration. The results demonstrate that strength is positively correlated with the overlap length. Fracture strain first increases up to a maximum and then decreases with the increase in overlap length. When the temperature increases from 300 to 900 K, the ultimate stress of the welded nanowires decreases from 1.18 to 0.87 GPa, and the welding stress decreases from -0.54 to -0.26 GPa. The crystal orientation significantly influences the deformation mechanism. For samples welded by nanowires with the same crystal orientation, the primary deformation mechanisms are twinning and dislocation slip. However, for samples welded by nanowires with different crystal orientations, the deformation is primarily mediated by the grain boundary slip. The research can enhance the understanding of the cold welding behavior for low-dimensional materials and is hopeful to provide some valuable guidance for the bottom-up fabrication and assembly of HEA nanocomponents.