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We investigate the deformation behavior of bimetallic and trimetallic nanoscale multilayer metallic composites under biaxial loading using molecular dynamics. Three types of structures were studied: (a) Cu–Ni fcc/fcc bilayer, (b) Cu–Nb fcc/bcc bilayer, and (c) Ni–Cu–Nb fcc/fcc/bcc trilayer. A configuration with a dislocation structure inside is generated by initially loading a perfect structure to a high strain to nucleate dislocations, then completely unloading it and loading it again. The comparison between the deformation behavior of bilayer and trilayer structures revealed that the Cu–Ni is more ductile, the Cu–Nb is stronger, and the trilayer structure exhibits both high strength and ductility.

We investigate the pseudoelastic behavior at room temperature of composite nanowires using molecular dynamics simulations. The nanowires are composed of a nickel core surrounded by a copper shell, leading to high coherency stresses. The coherency and surface stresses cause the nanowires to undergo a lattice reorientation, by twinning, from ⟨001⟩ to ⟨110⟩ during relaxation. Nanowires of different cross-sectional areas (varying from 2.17×2.17 up to 2.9×2.9 nm2) were studied. In all cases, under tensile loading, the nanowires reorient to ⟨001⟩ and then under unloading reorient back to ⟨110⟩, thus exhibiting pseudoelastic behavior. This behavior is more pronounced in composite nanowires with a coherent interface than for single crystal nanowires.