A combined resistivity transmission electron microscopy (TEM) study has been done on heavily drawn Cuhyphen;20 volthinsp;percnt; Nb alloys (sohyphen;calledinsitualloys). The results show that electron scattering at Cuhyphen;Nb interfaces makes the major contribution to resistivity in heavily drawn wire. The dislocation contribution is small and constant at deformation strains greater than around 4, apparently as a result of dynamic recovery/recrystallization of the Cu matrix which occurs during roomhyphen;temperature drawing. Results of this study and other recent TEM dislocation studies indicate that the dislocation density in heavily drawn Cuhyphen;20 volthinsp;percnt; Nb material does not exceed 1011cmminus;2. It is demonstrated here that the 1013hyphen;thinsp;cmminus;2dislocation density predicted by the resistivity study of Karasek and Bevk lsqb;J. Appl. Phys.52, 1370 (1981)rsqb; is high because the interface scattering contribution is more strongly reduced by coarsening than they assumed. It is shown that resistivity measurements provide a means of evaluating an average Cu channel diameter in the aligned composite alloys formed at large deformation strains.
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