Annealing effects on the microstructure, electrical, and magnetic properties of jelly-rolled Cu–Nb composite wires

We report on the annealing effects on the microstructure, electrical, and magnetic properties of jelly-rolled Cu –xvol %Nb (x = 25, 33, 50, 63) composite wires, a promising material to be used in high-field magnets. During annealing at temperatures as high as 850 °C, noticeable changes take place in the microstructure, including recovery and recrystallization of copper and niobium, followed by partial spheroidization and further coarsening of niobium filaments. The influence of these microstructural changes on the electrical and magnetic properties of jelly-rolled Cu–Nb composite wires is discussed.