Simulation of the resistivity of heavily cold worked Cu-20 wt.%Nb wires

Abstract

Fiber reinforced in-situ metal matrix composites (MMCs) consisting of Cu and 20 wt.% Nb were produced by large strain wire drawing. The microstructure of the composite wires was investigated by use of optical and scanning electron microscopy. The resistivity of the MMC wires was examined as a function of strain and temperature and compared to that of pure Cu and Nb. A strong degradation of the electrical conductivity of the MMC after heavy deformation was experimentally observed. In this strain regime the fibre diameters and spacings are comparable with the mean free path of the conduction electrons. Corresponding simulations, accounting for inelastic scattering of conduction electrons at internal phase boundaries as primary and scattering at dislocations as secondary contribution to the total resistivity of the composite, were carried out.