Aluminum wire manufacturing method
A method for manufacturing an aluminum wire is provided. The aluminum wire includes an inner-layer conductor having one or a plurality of inner-layer alloy wires including aluminum and an outer-layer conductor having a plurality of outer-layer alloy wires including aluminum and provided on the inner-layer conductor. The method includes an outer-layer twisting step of twisting, over the inner-layer conductor, the outer-layer alloy wires provided on the inner-layer conductor, and an outer-layer rotational compression step of compressing the outer-layer alloy wires twisted in the outer-layer twisting step while being rotated in the same direction as the direction of the twisting in the outer-layer twisting step.
1. A method for manufacturing an aluminum wire comprising an inner-layer conductor having at least one inner-layer alloy wire including aluminum and an outer-layer conductor having a plurality of outer-layer alloy wires including aluminum and provided on the inner-layer conductor, the method comprising:
an inner-layer twisting step of twisting, in a twisting direction, a plurality of inner-layer alloy wires, including the at least one inner-layer alloy wire, to form the inner-layer conductor;
an inner-layer rotational compression step of compressing the plurality of inner-layer alloy wires twisted in the inner-layer twisting step;
an outer-layer twisting step of twisting, in the twisting direction and over the inner-layer conductor, the outer-layer alloy wires provided on the inner-layer conductor that is performed after the inner-layer rotational compression step; and
an outer-layer rotational compression step of compressing the outer-layer alloy wires twisted in the outer-layer twisting step while rotating the outer-layer alloy wires in a same direction as the twisting direction of the twisting in the inner-layer twisting step and the outer-layer twisting step.
2. The method according to claim 1 , wherein a twist pitch in the outer-layer twisting step is 13 mm to 30 mm.
3. The method according to claim 1 , further comprising, prior to the outer-layer twisting step:
a casting step of casting an alloy containing 0.5 mass % to 1.3 mass % of iron and 0 mass % to 0.4 mass % of magnesium, with the remainder including aluminum and impurities;
an annealing step of annealing the alloy cast in the casting step at a temperature of 250° C. to 450° C.; and
a wire drawing step of drawing the alloy obtained in the annealing step to provide the inner-layer alloy wire and the outer-layer alloy wires.
4. The method according to claim 1 , further comprising, prior to the outer-layer twisting step:
a casting step of casting an alloy containing 0.2 mass % to 1.2 mass % of magnesium, 0.1 mass % to 2.0 mass % of silicon, and the remainder including aluminum and impurities;
a first annealing step of appealing the alloy cast in the casting step at a temperature of 400° C. to 630° C.;
a wire drawing step of drawing the alloy obtained in the first annealing step to provide the inner-layer alloy wire and the outer-layer alloy wires; and
a second annealing step of annealing the inner-layer alloy wire and the outer-layer alloy wires obtained in the wire drawing step at a temperature of 100° C. to 300° C.
5. The method according to claim 1 , wherein the at least one inner-layer alloy wire is a first alloy, and wherein the plurality of outer-layer alloy wires is a second alloy that is different than the first alloy.