Abstract: Varying rules of tensile strength, electrical conductivity and iron-rich phase evolution of Cu-20wt%Fe in-situ composite strips under different finished product annealing processes were studied by means of tensile test, electrical conductivity test, SEM microstructure observation and energy spectrum analysis. The results show that after annealing, some iron-rich phases with small thickness can be dissolved into copper matrix. With the increase of annealing temperature, the dissolution of iron-rich phase increases, and the residual flat and long iron-rich phases eventually distribute intermittently. With the extension of annealing time, the tensile strength of the strip first decreases significantly to 380-440 MPa, then the decline rate slows down significantly, even fluctuates up slightly, and finally tends to be stable, meanwhile, the tensile strength decreases with the increase of annealing temperature. The conductivity of the strip increases rapidly to 31%IACS-37%IACS with the extension of annealing time, then changes slowly, fluctuates slightly, and finally tends to be stable. The ideal finished product annealing process for Cu-20wt%Fe in-situ composite strip is at 450 ℃ for 60 min.

Key words: Cu-20wt%Fe, in-situ composite, strip, microstructure, tensile strength, electrical conductivity