Copper-based alloy wire and methods for manufaturing the same

A manufacturing method of a copper-based alloy wire, comprising:

• providing a pre-formed wire made of a material selected from the group consisting of a copper-gold alloy, a copper-palladium alloy and a copper-gold-palladium alloy;
• step-by-step decreasing the wire diameter of the pre-formed wire to form a final wire with a wire diameter less than that of the pre-formed wire utilizing N steps of cold-work shaping steps, wherein in each of the (N−1)th and Nth steps of the cold-work shaping steps, the deformation is between 1% and 15% compared to an in-process wire from its immediately preceding cold-work shaping step, and wherein N is a positive integer equal to 3 or greater;
• and
• N steps of annealing steps performed on the in-process wire respectively between each of the cold-work shaping steps and after the Nth step of the cold-work shaping steps, wherein
• the (N−1)th step of the annealing steps between the (N−1)th and Nth steps of the cold-work shaping steps is performed at an annealing temperature of between 0.5 Tm and 0.7 Tm during an annealing period of between 1 second and 10 seconds, wherein Tm is the melting point in the Kelvin temperature scale of the material of the pre-formed wire;
• and
• the Nth step of the annealing steps after the Nth step of the cold-work shaping steps is performed at an annealing temperature of between 30K and 50K higher than that of the (N−1)th step of the annealing steps during an annealing period of between 2 seconds and 60 seconds, resulting in the final wire having a polycrystalline structure of a face-centered cubic phase and consisting of a plurality of equi-axial grains, and forming annealing twins in at least some of the grains, wherein the quantity of grains comprising the annealing twins is 10 percent or more of the total quantity of the grains of the final wire.