Size effects influence on conducting properties of Cu-Nb alloy microcomposites at cryogenic temperature

A comprehensive study has been carried out in relation to the conductivity of heavily deformed Cu-16wt%Nb nanostructured wires at room and cryogenic temperatures. When the true strain exceeds 5, the growth rates of the resistivity qualitatively change the behavior at all temperatures. It is shown that such behavior is defined mostly by interface scattering. At 10 K the stepwise increasing of resistivity has been found, what is speculated as a feature of amorphous regions formation at the interface of Cu/Nb. Simultaneously the superconducting transition temperature (Tcs) falls down due to proximity effect. The deviation of experimental Tcs values from predicted by classical model is discussed.