ON THE CORRELATION OF MICROSTRUCTURE AND ELECTROMAGNETIC PROPERTIES OF HEAVILY COLD-WORKED CU-20WT-PERCENT NB WIRES

Fibre or ribbon reinforced in situ metal matrix composites (MMCs) cons isting of Cu and 20 wt% Nb were produced by large strain wire drawing. The microstructure of the composites was investigated by means of opt ical and electron microscopy. The normal and superconducting propertie s of the MMC wires in the presence of external magnetic fields were ex amined and compared to the electromagnetic properties of pure Cu wires . The findings are discussed on the basis of the microstructural chang es during deformation. The current results substantiate that the amoun t of internal boundaries and the filament spacing have considerable in fluence on the normal and superconducting properties of Cu-20%Nb.