JPH02243733A - Copper alloy wire rod - Google Patents

Abstract

PURPOSE:To facilitate semisoftening treatment and to improve the mechanical strength and electrical conductivity in the wire rod by specifying the contents of Ag, Zr, Cu and oxygen. CONSTITUTION:The copper alloy wire rod is formed with the compsn. constituted of, by weight, 0.05 to 0.2% Ag, 0.003 to 0.01% Zr and the balance Cu. Then, the content of oxygen is regulated to <=10ppm. The above copper alloy wire rod has excellent mechanical strength and electrical conductivity and is preferably used for an extra fine wire of <=0.1mm wire diameter.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a copper alloy wire used as a thin copper wire or a winding core wire for a magnetic head, and in particular, to a copper alloy wire material having excellent mechanical strength, conductivity, and heat resistance. The present invention also relates to a copper alloy wire material that reduces die wear during wire drawing and is suitable for use in ultra-fine wires having a wire diameter of θ, 1 or less.

[Prior Art] Recently, with the development of electronic equipment, in the field of fine copper wire and winding core wire for magnetic heads (core wire for magnet wire), ultrafine copper wire with a wire diameter of 0.1 W or less, especially 50 μm or less, has been developed. Demand for ultra-fine copper wire is rapidly increasing.

By the way, as copper wires become thinner, wire breakage becomes more likely to occur during winding. For this reason, ultrafine copper wire (aSdrawn)
In addition to the excellent conductivity and appropriate softness (elongation) required of ordinary thin copper wires, it is also required to have high breaking strength.

Conventionally, in order to obtain appropriate elongation and high breaking strength, ultrafine copper wire has been subjected to semi-softening treatment after being drawn. In this case, if the complete softening temperature of the ultra-fine copper wire is low, the composition of the ultra-fine copper wire will change from a semi-softened state to a completely softened state when enamel is baked on the circumferential surface of the ultra-fine copper wire in a subsequent process. Therefore, desired breaking strength cannot be obtained.

For this reason, conventional ultrafine copper wires include copper alloy wires containing Zr, copper alloy wires containing Ag or sb, etc., copper alloy wires containing Sn, etc., and precipitated copper alloy wires such as Cr copper. Copper alloy wire with a high softening temperature is used.

[Problems to be Solved by the Invention] However, the above-mentioned copper alloy wire has the following problems.

First, in the case of a copper alloy wire containing Zr, the complete softening temperature is too high, so annealing to obtain semi-softening characteristics is difficult.

In addition, in the case of copper alloy wire containing Ag or sb, etc.
Although the complete softening temperature is appropriate, the annealing temperature range in which a semi-softened state can be obtained is narrow, so variations in the semi-softening characteristics after the semi-softening treatment are likely to occur.

Furthermore, in the case of a copper alloy containing Sn or the like, it is difficult to obtain the desired conductivity (95% IAC!S or more).

Furthermore, in the case of precipitated copper alloys such as Cr copper, even if they are completely softened and modified to make them easier to stretch, their breaking strength is high, but the dies used for wire drawing are subject to severe wear, and It is difficult to obtain conductivity of

The present invention has been made in view of such problems, and includes:
It is easy to undergo semi-softening treatment, has excellent mechanical properties such as breaking strength and elongation after treatment, and has excellent electrical conductivity.Furthermore, die wear during wire drawing is comparable to that of pure copper. The purpose of the present invention is to provide a copper alloy wire material that can suppress

[Means for Solving the Problems] The copper alloy wire according to the present invention contains Ag from 0.05 to 0.2.
Zr is contained in a proportion of 0.003 to 0.01% by weight, the remainder being Cu and unavoidable impurities, and the oxygen content is regulated to 10 ppm or less.

[Function] As mentioned above, the ultrafine copper wire made of an Ag-containing copper alloy has excellent mechanical strength such as breaking strength and elongation, and also has excellent electrical conductivity. However, the range of annealing conditions under which this ultra-fine copper wire can be semi-softened is extremely narrow. That is, when the annealing temperature is held constant, the appropriate annealing time range is extremely narrow, and when the annealing time is held constant, the appropriate annealing temperature range is extremely narrow. For this reason, variations in quality are likely to occur during the annealing process for semi-softening treatment.

On the other hand, an ultrafine copper wire made of a Zr-containing copper alloy has the advantage that the range of appropriate annealing conditions for semi-softening treatment is wide. but,
As mentioned above, since the complete softening temperature is too high, it is necessary to increase the annealing temperature or lengthen the annealing time for semi-softening treatment.

Based on the above-mentioned Ag-containing copper alloy, in order to eliminate its drawbacks, the present inventors added Zr, which has the effect of widening the range of appropriate annealing conditions. An ultrafine copper wire with a diameter of 30 μm was formed and annealing experiments were repeated. As a result, the alloy obtained by adding Zr in the content described in the claims to a copper alloy containing Ag in the content described in the claims also has the superior properties of the Ag-containing copper alloy. It has been found that the range of appropriate annealing conditions for semi-softening treatment can be widened without impairing mechanical properties and electrical conductivity. In this way, the present invention is designed to complement the characteristics of both Ag and Zr by adding both elements in a predetermined composition.

Next, the reasons for limiting the composition of each component of the copper alloy material according to the present invention will be explained.

L If the Ag content is less than 0.05% by weight, the effect of increasing the complete softening temperature cannot be obtained, and the enamel will be in a completely softened state when baked after semi-softening treatment, so it will be difficult to achieve the desired breaking strength. can't get it.

On the other hand, when the Ag content exceeds 0.2% by weight, the cost of Ag increases significantly and the conductivity of the ultrafine copper wire deteriorates. Therefore, the Ag content is 0.05 to 0.2
Weight%.

7.x If the Zr content is less than 0.003% by weight, the effect of Zr addition cannot be obtained and the range of appropriate annealing conditions cannot be expanded. On the other hand, when the Zr content exceeds 0.01% by weight, the conductivity of the ultrafine copper wire deteriorates and the annealing temperature becomes high, making annealing difficult. As a result, the Zr content is 0.
0.003 to 0.01% by weight.

acid! When the oxygen content exceeds ]Oppm, Z in the alloy wire
When combined with r, oxides such as Z r O2 increase, and wire breakage tends to occur during the process of wire drawing into ultra-fine copper wire.

For this reason, the oxygen content is regulated to 10 ppm or less.

[Example] Next, examples of the present invention will be described.

A copper alloy having the components shown in Table 1 below was melted in vacuum or in the atmosphere to obtain a copper alloy rod having a diameter of 20+ am.

Table 1 The rods of Examples 1 to 3 and Comparative Examples 1 to 6 were drawn to form ultrafine copper wires. As a result, the copper alloy rods of Examples 1 to 3 and Comparative Examples 1 to 5 could be continuously drawn into ultrafine copper wires with a wire diameter of 30 μm from 1 kg rods without breaking. On the other hand, in the case of the copper alloy rod of Comparative Example 6, the wire diameter of the 1 kg rod was 50 μm.
When drawing an ultra-fine copper wire of 500 m, wire breakage occurred four times.

Furthermore, the wear of the die during drawing of the copper alloy wires of Examples 1 to 3 and Comparative Examples 1 to 6 was comparable to that of pure copper.

Next, repeated annealing experiments were conducted on the ultrafine copper wires of Examples 1 to 3 and Comparative Examples 1 to 5, each having a wire diameter of 30 μm.
Breaking strength is 32kgf/- or more and elongation rate is 10%
The annealing temperature at which the above mechanical strength can be obtained was investigated.

However, at this time, a heating furnace with a furnace length of 90 cm was used, and the ultrafine copper wires of Examples 1 to 3 and Comparative Examples 1 to 5 were inserted into the heating furnace at a wire speed of 60 m/min.

As a result, the annealing temperature range in which the above-mentioned desired mechanical strength can be obtained is shown in Table 2 below. Further, the electrical conductivity of the semi-softened ultrafine copper wire obtained by this annealing is also shown in Table 2.

Table 2: The annealing temperature to obtain a semi-softened state is 30°C within the temperature range of 400 to 500°C.
It is preferable that there is a temperature range greater than or equal to the above.

Moreover, it is preferable that the conductivity is 95%lAC3 or more. Examples 1 to 3 all satisfied these desired conditions, and were able to reliably obtain extremely excellent mechanical and electrical properties.

On the other hand, Comparative Examples 1 to 6, which fall outside the scope of the claims of the present invention, were not satisfactory in any one or more of wire drawability, appropriate annealing temperature, processing temperature range, and electrical conductivity.

[Effect of the invention] As explained above, the copper alloy wire according to the present invention has a
5 to 0.2% by weight or more of Ag and 0.003 to 0.2% by weight.
Since it contains 0.1% by weight of Zr and the amount of oxygen is regulated to IOppm or less, semi-softening treatment can be easily performed. As a result, an ultrafine copper wire having excellent mechanical strength such as breaking strength and elongation as well as electrical conductivity can be obtained. Also,
There is also extremely little wear on the dies used to draw ultra-fine copper wire.

Claims (1)

[Claims] (1) 0.05 to 0.2% by weight of Ag and 0.00% by weight
A copper alloy wire material having a composition containing 3 to 0.01% by weight of Zr, the remainder being Cu and unavoidable impurities, and controlling the oxygen content to 10 ppm or less.