Heat Treatment Effect on the Microstructure and Properties of a High-Strength and High-Conductivity Cu–Nb–Cu Microcomposite

Cu-Nb-Cu microcomposite reinforced by Nb tube was successfully fabricated by accumulative drawing and bundling process. When the strength of the Cu-Nb-Cu composite reaches above 1 GPa, the conductivity can reach 67% International Annealed Copper Standard (IACS). The annealing effects on the microstructure and properties of the Cu-Nb-Cu microcomposite have been thoroughly discussed. Annealing temperature at 750 °C can lead to an obvious change of microstructures. Both the partial spheroidization and further coarsening of niobium filaments in Cu-Nb-Cu microcomposite have been revealed. The influences of the microstructure changes on the mechanical and electrical properties have also been analyzed.