Hardness, electrical resistivity, and modeling of in situ Cu-Nb microcomposites

This paper reports our investigation on the evolution of microstructure, hardness, and electrical conductivity of in situ Cu-16.5 vol.%Nb microcomposites as a function of drawing strain. Both interface area density and lattice distortion were taken into account for analyzing the hardness and resistivity at different levels of plastic strain. A model was developed for describing microstructure dimensions including both spacing and curl of Nb ribbons. Based on this model, a modified Hall-Petch formula was derived. Our results suggest that interface area density and lattice distortion have significant impacts on both hardness and electrical resistivity.