JPH06187821A - Copper alloy wire - Google Patents

Abstract

PURPOSE:To provide a coil winding copper wire excellent in conductivity which allows high speed windup, even if the cross section of a wire material is small, by using copper alloy containing a specified weight ratio of tin and magnesium with an oxygen content of less than specified weight ratio. CONSTITUTION:Weight ratio 22-1000ppm of tin and weight ratio 11-500ppm of magnesium are added to copper to form a copper alloy with an oxygen content of less than 30ppm, and then a super fine wire of the copper alloy of 17-60mum in diameter is annealed at a temperature of 250-350 deg.C after cold plastic working. This copper wire is free from cutting in initiating windup at a high speed of 200m or more per minute and so it is useful as a coil winding. Oil enamel as well as formalin resin and polyurethane enamel are applicable as insulator as usual to cover the outer periphery.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copper alloy wire, and more particularly to a copper alloy wire which has a large tensile strength and conductivity and is suitable as an ultrafine diameter copper wire used for a coil winding or the like.

[0002]

2. Description of the Related Art An enameled wire is mainly used for winding a coil such as a stepping coil for a watch and a coil for a magnetic recording head. Wires with a diameter of 0.06 mm or less are generally called extra-fine wires, and coils using extra-fine wires often have a large number of turns, so the winding is 200 m / min (coil diameter 6.
If it is 5 mm, it is often performed at a high speed of about 10,000 rpm).

Conventionally, oxygen-free copper (abbreviated as OFC) and tough pitch copper (abbreviated as TFC), which have high conductivity, have been widely used as the conductor material of the enamel wire for coil winding.

[0004]

However, oxygen-free copper (OFC) and tough pitch copper (TFC), which have hitherto been used as the conductor material of the enameled wire for coil winding, have high conductivity but a diameter of 0. When used as a conductive material for ultrafine wires of 0.6 mm or less, the winding is 200 m / min (coil diameter 6.5 mm).
If this is done at a high speed of about 10000 rpm), wire breakage is likely to occur at the start of winding work. This is because the cross-sectional area of the wire becomes smaller, the winding speed becomes higher, the tension that is inevitably received at the time of winding becomes larger, and further, a particularly large tension is applied at the start of the winding work. .

For example, the winding of a wire having a small diameter is 100
There is a strong demand for a copper wire for coil winding, which does not cause disconnection due to the tension received at the start of winding work even at a high speed of about 00 rpm.

Therefore, it is an object of the present invention to realize a copper wire for coil winding, which has a small cross-sectional area, does not cause a disconnection at the start of high-speed winding work, and has excellent conductivity. Is.

[0007]

With the copper wire of the present invention, a copper wire for coil winding, which has a small cross-sectional area, does not cause disconnection at the start of high-speed winding work and has excellent conductivity. To achieve this, 22 to 1000 ppm tin alone and 1
A copper wire which contains 1 to 500 ppm of magnesium simple substance, has an oxygen content of less than 30 ppm, and the balance is copper, and is a copper wire (hereinafter, the copper alloy wire is referred to as a copper wire for convenience).
Configured. Annealing is preferably performed after casting and wire drawing.

When the content of tin is 1000 ppm or more, the conductivity is lowered to less than 90% IACS, and the segregation of tin occurs, so that the wire breakage tends to occur.
Even when the content of magnesium is 500 ppm or more, segregation of magnesium easily causes disconnection. On the other hand, when the tin content is 22 ppm or less or the magnesium content is 11 ppm or less, the tensile strength is reduced and the elongation rate under a constant load is also reduced.
The ratio of the tin and magnesium contents is not particularly limited, but is preferably about 4: 1 to 1: 1.

An important feature of the copper alloy wire of the present invention is that it contains a specific amount of tin and a specific amount of magnesium at the same time.
Tin or magnesium alone has low tensile strength. As will be described later in detail, 1 in a high temperature softening test under specified conditions
At the heating temperature at which 0% elongation is obtained, the copper alloy of the present invention has a tensile strength of about 35 kg / mm ² , but tin or magnesium alone does not reach 30 kg / mm ² as in OFC.

The present invention is particularly useful when applied to an ultrafine wire having a diameter of 0.06 mm (60 μm) or less. Particularly, it is useful for a copper wire having a diameter of 17 to 60 μm. The copper wire of the present invention is useful as a coil winding because it does not cut at the start of winding even at high speed winding (for example, linear velocity of 200 m / min or more). In order to use it as a coil winding, it is necessary to coat the outer circumference with an insulator, but as the insulator, one normally used for an enameled wire or the like can be applied. As the insulator, in addition to oil-based enamel, any of formal resin, nylon enamel, polyurethane enamel, polyester enamel, polyesterimide enamel, polyamideimide enamel, polyimide enamel, self-fusing enamel and the like may be used.

[0011]

EXAMPLES Examples will be shown below for further detailed explanation of the present invention. Example 1 One example of the copper wire of the present invention is tin 330 ppm,
It is a copper (alloy) wire having a diameter of 0.05 mm and made of a copper alloy containing 165 ppm of magnesium and 20 ppm of oxygen.

This copper wire is manufactured as follows.
To the copper having an oxygen content of 20 ppm melted in an argon atmosphere, a tin content of 330 ppm and a magnesium content of 165 ppm were adjusted so that a 0.3% tin-copper master alloy and a 0.13% magnesium-copper master alloy were prepared. A copper alloy is prepared by adding an alloy, and the diameter is 20 mm and the length is 250 mm in an argon atmosphere.
It is cast into a cylindrical shape (weight: about 700 g). This is swaged to a diameter of 8.0 mm, and the diameter is 2.8 mm by the conventional method.
After wire drawing at 90 ° C. in an argon atmosphere at a temperature of 350 ° C.
Minute annealing is performed, and cold drawing is performed to a diameter of 0.05 mm.

The copper wire thus obtained was subjected to a tensile test at a crosshead speed of 20 mm / min. The tensile strength was 72 kgf / mm ² and the elongation was 1.5%.

Further, the obtained copper wire has a temperature of 20 to 500.
After performing isothermal annealing at ℃ for 1 hour, the tensile test was conducted in the same manner. The results are shown in FIGS. 1 (A) and 1 (B) together with a comparative example using OFC described later. In addition, the electrical conductivity of the copper wire that was annealed at the same temperature was measured.

As can be seen from FIG. 1 (B), the copper wire obtained above has an elongation of 10% when annealed at a temperature of about 315 ° C., and as shown in FIG. 1 (A), at this temperature. The tensile strength of the annealed sample was 35 kgf / mm ² (all are interpolated in the graph). Also, the temperature is about 300 ℃ and 3
The conductivity of the copper wire annealed at 25 ° C. is 98.4% IAC
It was S.

[Comparative Example] The same as Example 1 except that tin or magnesium was not added, and the diameter was 0.0.
I made a 5mm copper wire. The addition amount of tin or magnesium is as shown in Table 1.

As in Example 1, a tensile test was conducted after isothermal annealing at a temperature of 20 to 500 ° C. for 1 hour.
From the results of the tensile test, the same method as in Example 1 (see FIG.
(See (A) and (B)), the annealing temperature at which the elongation rate reached 10% for each copper wire and the tensile strength of the sample annealed at that temperature were obtained. The results are shown in Table 1.

[0018]

[Conventional Example] An OFC copper wire having a diameter of 0.05 mm was manufactured in the same manner as in Example 1 except that neither tin nor magnesium was added. As a result of performing the same tensile test as in Example 1, the tensile strength was 62 kgf / mm ² , and the elongation rate was 1.5%. After the isothermal annealing at a temperature of 20 to 500 ° C. for 1 hour, the result of the tensile test is shown in FIG.
As shown in (A) and (B). The elongation reaches 10% at the annealing temperature of about 155 ° C., but as shown in FIG. 1A, the tensile strength of the sample annealed at this temperature was about 27.5 kgf / mm ² . That is, the growth rate is 1
The tensile strength when treated to 0% is 30 kgf /
Not reach mm ² .

[Example 2] An OFC copper wire having a diameter of 0.05 mm was manufactured in the same manner as in Example 1 except that the weight ratio of tin and magnesium was kept at 2: 1 and the addition amount was changed. .

As in Example 1, a temperature of 20 to 500 ° C.
After isothermal annealing for 1 hour at a constant tension of 31 kgf / mm
^The elongation (rate) occurring at ² was plotted as a function of the tin addition amount X (magnesium addition amount X / 2). The graph obtained is shown in FIG.

As is clear from FIG. 2, when the weight ratio of tin and magnesium is 2: 1, the tin addition amount X is 22 p.
If it is less than pm (the amount of magnesium added is less than 11 ppm), the elongation generated at a tension of 31 kgf / mm ² is less than 10%. The electrical conductivity measured for a copper wire having a diameter of 0.05 mm was 90% IACS or more when the tin addition amount X was in the range of 22 to 1000 ppm (magnesium addition amount of 11 ppm to 500 ppm).

[0023]

INDUSTRIAL APPLICABILITY The copper (alloy) wire of the present invention is extremely useful as a coil winding, and even when the cross-sectional area of the wire is small, at the start of winding work performed at a high speed (for example, a linear speed of 200 m / min or more) Does not cause wire breakage and has high conductivity.

[Brief description of drawings]

FIG. 1 (A) is a graph showing the relationship between temperature and tensile strength in isothermal annealing of an example of a copper wire according to the present invention and a conventional example, and FIG. 1 (B) is a graph of a copper wire according to the present invention. It is a graph which shows the relationship between the temperature in an isothermal annealing and the elongation rate in a tensile test of an Example and a prior art example.

FIG. 2 is a graph showing the relationship between the amount of tin added and the elongation generated at a constant tension of 31 kgf / mm ² in another example of the copper wire according to the present invention.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuaki Onuki 3550 Kitayo-cho, Tsuchiura-shi, Ibaraki Hitachi Cable Ltd. (72) Inventor Koichi Tamura 3550 Kidayo-cho, Tsuchiura-shi, Ibaraki Hitachi Cable Ltd. Inside the Metal Research Laboratory (72) Inventor Yuji Kajikawa 1500 Kawajiri-cho, Hitachi City, Ibaraki Prefecture Toraura Factory, Hitachi Cable Co., Ltd.

Claims (5)

[Claims] 1. Tin in a weight ratio of 22 to 1000 ppm,
A copper alloy wire comprising a copper alloy containing 11 to 500 ppm by weight of magnesium and less than 30 ppm of oxygen by weight, with the balance being copper. 2. The copper alloy wire according to claim 1, which has a diameter of 17 to 60 μm. 3. The copper alloy wire according to claim 1, which is for coil winding. 4. The copper alloy wire according to claim 1, wherein the copper alloy is annealed after cold plastic working. 5. The copper alloy has a temperature of 2 after cold plastic working.
The copper alloy wire according to claim 1 or 2, which is annealed at 50 ° C to 350 ° C.