Abstract:Cu-1Sn and Cu-1Sn-0.5P alloy casting rods with a diameter of 12.5 mm were prepared by downward continuous casting process, in view of the insufficient weldability and small resistance adjustment range of Cu-Sn alloy system used in new energy vehicles. The cast rods were drawn into 2.6 mm wires by multi-pass cold drawing with a single inverted disc drawing machine. The microstructure evolution, mechanical properties and electrical conductivity of Cu-1Sn and Cu-1Sn-0.5P alloys were comprehensively compared and analyzed by metallographic microscope, scanning electron microscope, tensile test and resistivity meter. Compared with Cu-1Sn alloy, the addition of P element formed a P-rich phase in Cu-1Sn-0.5P alloy and deformed into fiber-reinforced structure during cold drawing. The tensile strength of Cu-1Sn-0.5P alloy wire increased from 577.5 MPa to 796.1 MPa due to the hindering effect of solid solution P atoms and P-rich second phase dislocations in the copper matrix. However, the plasticity decreased slightly while the elongation decreased from 1.0% to 0.67%, and the reduction of area decreased from 65.8% to 36.0%. Finally, the conductivity of Cu-1Sn-0.5P alloy wire decreased from 52.3%IACS to 24.6%IACS due to the increase of electron scattering caused by the addition of P element. However, after cold drawing, the conductivity increased by 2.45%IACS.