Microstructures and strengthening mechanisms of Cu/Ni/W nanolayered composites

(2013) Microstruc-tures and strengthening mechanisms of Cu/Ni/W nanolayered composites. Notice: Changes introduced as a result of publishing processes such as copy-editing and formatting may not be reflected in this document. For a definitive version of this work, please refer to the published source: Abstract Cu/Ni/W nanolayered composites with individual layer thickness ranging from 5 nm to 300 nm were prepared by a magnetron sputtering system. Microstructures and strength of the nanolayered composites were investigated by using nanoindentation method combined with theoretical analysis. Microstructure characterization reveals that the Cu/Ni/W composite consists of typical Cu/Ni coherent interface and Cu/W and Ni/W incoherent interfaces. Cu/Ni/W composites have an ultrahigh strength and a large strengthening ability compared with bi-composites. Summarizing the present results and those reported in the literature, we systematically analyze the origin of the ultrahigh strength and its length scale dependence by taking into account of the constituent layer properties, layer scales and heterogeneous layer/layer interface characteristics including lattice and modulus mismatch as well as interface structure.