Modulation of strength and plasticity of multiscale Ni/Cu laminated composites

The multiscale Ni/Cu laminated composites with different layer-thickness ratios and grain sizes were designed and prepared by the dual-bath electrodeposition technique. Strength and ductility of the multiscale Ni/Cu laminated composites were investigated by tensile tests at room temperature. The experimental results show that the ultrafine-grained Ni/coarse-grained Cu laminated composites with a thickness ratio of 20:1 have a good synergy of strength and ductility. For this Ni/Cu laminated composite, not only could the large strain hardening ability and the good plastic deformation stability of the thick ultrafine-grained Ni layers be obtained, but also the ductility of the ultrathin coarse-grained Cu layers and the resistance to the development of strain localization of the ultrafine-grained Ni layers did not become degraded. Basic mechanisms for optimizing the strength and the ductility in the multiscale Ni/Cu laminated composites are discussed.