Copper wire and process for making copper wire

Copper wire and method of manufacturing copper wire

This application is a partial continuation of the U.S. Patent Application Serial No. 60/000277 filed on June 16, 1995, and the disclosure of the application is incorporated herein by reference in its entirety.

The present invention relates to a novel form of copper wire and a novel method of manufacturing copper wire. The copper wire is characterized by having a substantially uniform and non-oriented grain structure with almost no columnar grains. The method includes forming an electrodeposited copper foil with low fatigue ductility, cutting the copper foil to form one or more strands, and shaping the strands to make the strands have desired cross-sections and dimensions.

The traditional method of manufacturing copper wire includes the following steps. The electrolytic copper (whether it is electrorefined, electro won, or both) is melted, cast into a rod shape, and hot rolled into a strip shape. The strip is then cold-worked during the drawing die to systematically reduce its size while extending the wire. In a typical operation, a copper bar manufacturer casts molten electrolytic copper into a rod, the cross section of which is essentially trapezoidal with rounded edges and a cross section of about 7 square inches; the rod passes through a preparation stage to trim its corners. Then it passes through 12 rolling stations and comes out in the form of 0.3125" diameter copper strips. The copper strips are then reduced to the desired copper wire size through a standard circular drawing die. Typically, these reduction steps are performed by a series of machines , Plus a final annealing step and in some cases, an intermediate annealing step to soften the processed copper wire.

The traditional copper wire manufacturing method consumes a considerable amount of energy and requires a lot of labor and investment costs. The melting, casting and hot rolling operations will cause the product to be oxidized and potentially contaminated by foreign objects such as refractory materials and roll materials, which may cause problems for the wire puller later, usually due to the problem of wire breakage during drawing.

With the method of the present invention, the copper wire can be manufactured in a simplified and less expensive way than the prior art. The copper source used in the method of the present invention is, for example, copper shot, copper oxide or recycled copper. The method of the present invention does not need to use the steps of manufacturing a copper cathode first, and then melting the cathode, casting and hot rolling to produce the copper strip raw material used in the prior art.

The present invention relates to a copper wire having a substantially uniform and non-directional grain structure with almost no columnar grains. The present invention also relates to a method of manufacturing a copper wire, which includes: cutting a copper foil to form at least a general copper wire. The copper foil is an annealed electrodepositable copper with a substantially uniform and non-directional grain structure that contains almost no columnar grains. The copper foil is characterized by having a fatigue ductility of at least about 25% after being annealed at 177° C. for 15 minutes, and the stranded copper wire is shaped so that the strand has a desired cross-sectional shape and size. The present invention also relates to a method of manufacturing copper wire, which includes flowing an aqueous electrolyte solution between an anode and a cathode and applying an amount of voltage to the anode and the cathode to deposit a copper foil on the cathode, the electrolyte The solution is characterized by having a chloride ion concentration of up to about 5 ppm and an organic additive concentration of up to about 0.2 ppm; cutting the foil to form at least one strand; and forming the strand to make the strand have the desired Cross-sectional shape and size.

In the attached drawing, the same parts and special items are numbered with the same indicator numbers.

Figure 1 is a flow chart illustrating an embodiment of the present invention, in which copper is electrodeposited on a vertically oriented cathode to form a copper foil, the foil is scribed and cut and removed from the cathode to become copper strands, and then The copper wire is shaped to make the copper wire have the desired cross-sectional shape and size; Figure 2 is a flowchart illustrating another embodiment of the present invention, in which copper is electrodeposited on a horizontally oriented cathode to form a copper foil sheet , And then take out the foil from the cathode, cut to form one or more strands of copper wire, and then shape the copper strands to form a copper wire with the desired cross-sectional shape and size; Figures 3-20 illustrate the method according to the present invention. The cross-sectional shape of the finished copper wire; Figure 21 is a photomicrograph of the cross-section of the copper foil sample No. 5 in Example 1 taken at 800× magnification; and Figure 22 is the copper foil No. 8 in Example 1 A photomicrograph of the cross-section of the sample taken at 800× magnification.

The copper wire of the invention has a unique and novel combination of characteristics. In one embodiment, the copper wire has a substantially uniform non-directional crystal grain structure with almost no columnar crystal material. In one embodiment, the copper wire of the present invention is substantially free of twin boundaries. In one embodiment, the copper wire of the present invention is substantially non-porous. The expressions "almost no columnar crystal material", "essentially no twin boundary" and "substantially non-porous" refer to the microscope or transmission electron of the copper wire of the present invention in most cases Microscopy (TEM) analysis has shown that these copper wires have no columnar grains, no twin boundaries or porosity, but coupling may also observe the formation of a small number of columnar crystals, the formation of twin boundaries and the formation of twin boundaries. / Or the fact of porosity. In one embodiment, the copper wire of the present invention does not contain oxide inclusions. An advantage of the copper wire of the present invention is that it can be drawn more easily than prior art copper wires.

In one embodiment, the copper wire of the present invention has an average grain size of up to about 8 microns, and in one embodiment, has an average grain size in the range of about 0.5 to about 8 microns. In one embodiment, the copper wire of the present invention made before any annealing or heat treatment has an average grain size in the range of up to about 5 microns, and in one embodiment, the average grain size is about 0.5 to about In the range of 5 microns, and in one embodiment, in the range of about 1 to about 4 microns.

In one embodiment, the ultimate tensile strength (UTS) of the copper wire of the present invention at 23° C. is in the range of about 60,000 psi to about 95,000 psi, and in one embodiment, it is in the range of about 60,000 psi to about 75,000 psi . In one embodiment, the UTS of the copper wire at 180°C is in the range of about 22,000 psi to about 32,000 psi, and in one embodiment, it is in the range of about 23,000 psi to about 30,000 psi, and in an implementation In the example, it is in the range of about 25,000 psi to about 28,000 psi. In one embodiment, the elongation rate of the copper wire of the present invention at 23° C. is 8% to about 18%, in one embodiment, about 9% to about 16%, and in one embodiment, about 9% to about 14%. In one embodiment, the elongation of the copper wire at 180° C. is about 24% to about 45%, in one embodiment, about 27% to about 41%, and in one embodiment, about 29% to about 45%. About 38%.

In one embodiment, the copper wire of the present invention is cold worked to a reduction rate of about 60%, and the tensile strength of the copper wire is in the range of about 65,000 psi to about 90,000 psi, and in one embodiment, it is in the range of about 70,000 psi to about 70,000 psi. In the range of about 75,000 psi, the elongation is about 0% to about 4%, in one embodiment, about 0% to about 2%, and in an embodiment, about 1%.

In one embodiment, the copper wire of the present invention is cold worked to a shrinkage rate of about 60% and then annealed at 200° C. for two hours. The tensile strength of this copper wire is in the range of about 25,000 psi to about 40,000 psi and in one embodiment is in the range of about 27,000 psi to about 30,000 psi, and it has an elongation of at least about 30%, and is In the examples, it is about 30% to about 40%.

In one embodiment, the copper wire of the present invention has a conductivity of at least about 100% IACS (International Annealed Copper Standand), and in one embodiment, about 100% to about 102.7% IACS.

In the first embodiment, the present invention relates to a method of manufacturing a copper wire, which includes flowing an aqueous electrolyte solution between an anode and a cathode and applying an amount of voltage across the anode and the cathode so that the cathode Depositing a copper foil thereon, the electrolyte solution is characterized by having a chloride ion concentration of up to about 5 ppm and an organic additive concentration of up to about 0.2 ppm; cutting the foil to form at least one strand; and forming the strand to Make the strands have the desired cross-sectional shape and size.

The copper foil used in the method of the present invention shows a unique and novel combination of high fatigue ductility electrodeposited copper foil. These copper foils are copper foils that can be annealed at a low temperature, which have a substantially uniform and non-oriented grain structure with almost no columnar grains. The foil is characterized in that it has at least about 25% after being annealed at 177°C for 15 minutes. Fatigue ductility. In one implementation, these foils are annealed foils, which are equivalent to having a fatigue ductility of at least about 65%. The procedure for measuring fatigue ductility is contained in IPC-TM-650 Inspection Method 2.4.2.1. The fatigue ductility is calculated using the following equation.

<maths><img file="TW336325B_D0001.tif" /></maths>In equation (1), Df is fatigue ductility (inch/inch (×100.0%)), Nf is cycles-to-failure, Su is final tensile strength (psi), E is elasticity Modulus (psi), tM is the thickness of the core (inch), t is the thickness of the specimen in microns (inch), and p is the radius of curvature of the mandrel (inch) within 0.005 mm [0.0002 inch].

In one embodiment, these copper foils have high ultimate tensile strength for easy handling and surface quality control, and high elongation at high temperature to reduce cracking. In one embodiment, the copper foil has a controlled low profile. In one embodiment, the copper foil does not contain oxide inclusions.

In one embodiment, these copper foils are characterized by having a substantially uniform non-oriented grain structure with almost no columnar grains. In one embodiment, these foils have almost no twin boundaries. In one embodiment, the copper foils are substantially non-porous. As indicated above, expressions such as "almost no granular crystal grains", "almost no twin boundaries" and "substantially non-porous" mean that in most cases, the copper wire microscope of the present invention or Transmission electron microscopy (TEM) analysis shows that these copper wires have no columnar grains, no twin boundaries or no porosity, but a small amount of columnar crystals may also be observed in the coupling. Facts of formation and/or porosity.

In one embodiment, the copper foils produced have an average grain size in the range of up to about 3 microns before any annealing or heating treatment, and in one embodiment, the average grain size is It is in the range of about 0.5 to about 3 microns, and in one embodiment, it is in the range of about 1 to about 2 microns. In one embodiment, these foils are heat-treated at 177°C for 15 minutes, and these foils have an average grain size of up to about 5 microns, and in one embodiment, about 1 to about 5 microns, and In one embodiment, it is about 2 to about 4 microns. In one embodiment, the foils are heat treated at a temperature exceeding about 200° C. for at least about 30 minutes, and the foils have an average grain size of up to 8 microns, and in one embodiment, about 3 to about 8 Micrometers, and about 4 to about 7 micrometers in one embodiment.

In one embodiment, when these foils are produced, before any annealing or heat treatment, the transverse UTS at 23° C. is in the range of about 60,000 psi to about 95,000 pai, and in one embodiment, it is about 60,000. psi to about 85,000 pai, and in one embodiment, from about 65,000 psi to about 75,000 psi, which uses IPC-TM-650 Test Method 2.4.18. In one embodiment, the transverse UTS of these foils at 180°C is in the range of about 22,000 psi to about 32,000 psi, and in one embodiment, about 23,000 psi to about 30,000 psi, and in one embodiment, It is about 25,000 to about 28,000 psi, which is measured using the aforementioned inspection method. In one embodiment, the lateral elongation of these foils at 23° C. is about 8% to about 18%, and in one embodiment, about 9% to about 16%, and in one embodiment, about 9%. % To about 14%, which is measured using the aforementioned test method. In one embodiment, the transverse elongation of these foils at 180° C. is about 24% to about 45%, and in one embodiment, about 27% to about 41%, and in one embodiment, about 29%. % To about 38%, which is measured using the aforementioned test method.

In one embodiment, these copper foils are heat-treated or annealed at 177°C for 15 minutes, and the lateral UTS of these foils at 23°C is in the range of about 42,000 psi to about 70,000 psi, and in one embodiment About 44,000 psi to about 65,000 psi, and in one embodiment, about 46,000 psi to about 60,000 psi, which is measured using IPC-TM-650 Test Method 2.4.18. In one embodiment, the transverse UTS of these foils at 180°C is in the range of about 22,000 psi to about 32,000 psi, and in one embodiment, about 23,000 psi to about 30,000 psi, and in one embodiment, It is about 25,000 to about 28,000 psi, which is measured using the aforementioned inspection method. In one embodiment, the lateral elongation of these foils at 23° C. is about 15% to about 31%, and in one embodiment, about 17% to about 27%, and in one embodiment, about 19%. % To about 23%, which is measured using the aforementioned test method. In one embodiment, the lateral elongation of these foils at 180°C is about 24% to about 45%, and in one embodiment, about 27% to about 41%, and in one embodiment, about 29%. % To about 37%, which is measured using the aforementioned test method.

In one embodiment, the copper foil is heat-treated or annealed at a temperature exceeding about 200°C for at least about 30 minutes or longer, and these foils are inspected at 23°C using IPC-TM-650 inspection method 2.4.18 The lateral UTS obtained at this time is in the range of about 36,000 psi to about 48,000 psi, and in one embodiment, about 38,000 psi to about 46,000 psi, and in one embodiment, about 40,000 psi to about 45,000 psi. In one embodiment, the transverse UTS obtained when these foils are inspected using the aforementioned inspection method at 180° C. is in the range of about 22,000 psi to about 32,000 psi, and in one embodiment, it is in the range of about 23,000 psi to about 30,000 psi. In one embodiment, it is about 25,000 psi to about 28,000 psi. In one embodiment, the transverse elongation of these foils obtained by using the aforementioned inspection method at 23° C. is about 23% to about 36%, and in one embodiment, about 25% to about 34%. In one embodiment, it is about 27% to about 32%. In one embodiment, the transverse elongation of these foils is about 25% to about 48% when tested at 180° C. using the aforementioned inspection method, and in one embodiment Medium is about 27% to about 42%, and in one embodiment, it is about 29% to about 38%.

In one embodiment, the transverse fatigue ductility measured by IPC-TM-650 Test Method 2.4.2.1 of these copper foils is in the range of about 15% to about 65% before being subjected to any annealing or heating treatment. Within, and in one embodiment, it is about 15% to about 55%, and in one embodiment, it is about 20% to about 50%. In one embodiment, these foils are heated at 177°C for 15 minutes and the transverse fatigue ductility of these foils is at least 25%, and in one embodiment, it is in the range of about 45% to about 90%, In another embodiment, it is about 55% to about 80%, and in one embodiment, it is about 65% to about 75%. In one embodiment, these foils are subjected to heat treatment at a temperature exceeding about 200°C for at least about 30 minutes, and the transverse fatigue ductility of these foils is at least about 65%, and in one embodiment, it is between 65% and 65%. Within the range of about 120%, in one embodiment, it is about 65% to about 11%, and in one embodiment, it is about 65% to about 100%.

In one embodiment, these copper foils are made and before any annealing or heat treatment, using a 2 mm mandrel in the transverse direction and accepting a load of 84 grams on the foil, which can withstand about 150 to about 270 at break. Bending cycles, and in one embodiment, they endured about 170 to about 270 bending cycles before breaking, and in another embodiment, they endured about 190 to about 250 bending cycles before breaking. In one embodiment, the foils are heat treated at 177°C for 15 minutes and the foils can withstand about 220 to about 360 bending cycles before breaking, and in one embodiment, about 240 to about 340 bending cycles, In one embodiment, about 260 to about 320 bending cycles can be tolerated before breaking. In one embodiment, these foils are subjected to heat treatment at a temperature exceeding about 200°C for at least about 30 minutes and these foils can withstand about 260 to about 500 bending cycles before breaking, and in one embodiment, about 300 To about 440 bending cycles, and in one embodiment, to endure about 340 to about 400 bending cycles before breaking.

The copper foil used in the manufacture of copper wires generally has a matte side original foil thickness of about 1 to about 10 microns, Rtm, and in one embodiment, about 2 to about 8 microns, and in one embodiment, about 3 to about 6 microns . Rtm means the average value of the maximum peak-to-valley vertical distance contained in 5 consecutive sampling lengths, and it can be used with the Surftronic 3 proflometer (proflometer) sold by Lei-Ces Lei-Cester, Rank Taylor Hobson, Ltd., UK. Measurement. The Rtm of these foils on their glossy surface is generally less than about 5 microns, and in one embodiment is in the range of about 2 to about 6 microns, and (in another embodiment) is in the range of about 2 to about 5 microns.

The weight of these copper foils is usually about 1/8 to about 14 ounces per square foot, and in one embodiment, about 1/4 to about 6 ounces/square meter, and in one embodiment, about 3/ 8 to about 6 ounces/square foot, and in one embodiment, about 1/2 to about 2 ounces/square foot. In one embodiment, these foils have a weight of about 1/2 oz/square foot. A foil with a weight of 1/2 ounce per square foot has a nominal thickness of about 17 microns. A foil with a weight of 1 ounce per square foot has a nominal thickness of about 70 microns. In one embodiment, these foils have a thickness in the range of about 10 to about 250 microns. The Rtm of thinner foils tends to be lower than the Rtm of thicker foils. For example, in one embodiment, the weight of 1/2 ounce per square foot of the foil, the matte side of the original foil Rtm is in the range of about 1 to about 4 microns, and in another embodiment, the weight For a foil of 2 ounces per square foot, the original foil Rtm of the matte side is in the range of about 5 to about 7 microns.

In one embodiment, the present invention relates to a method of manufacturing copper wire, which includes using a critical concentration of chloride ions of about 5 ppm or less and preferably 0 level, and about 0.2 ppm or less and more Preferably, the electrolyte solution of 0 organic additives (such as animal glue) is used to electrodeposit copper foil, and then the foil is cut to form one or more strands, and then they are shaped to make the strands have the desired Cross-sectional shape and size.

The electrolyte solution is formed by dissolving copper raw materials, which can be copper pellets, copper wires, copper oxide or recycled copper, in a sulfuric acid solution. The copper raw materials, preferably sulfuric acid and water, are all high-purity substances. The electrolyte solution can be purified and filtered before entering the electroforming battery. When a voltage is applied between the anode and the cathode, the electrodeposition of copper occurs at the cathode. The current used is preferably a direct current or an alternating current circuit with current and electrical bias.

The cathode can be vertically or horizontally mounted and in the form of a cylindrical mandrel. The anode is adjacent to the cathode and has a curved shape that matches the curved shape of the cathode to create a uniform gap between the anode and the cathode. The distance between the cathode and the anode is usually about 0.2 to about 2 cm. In one embodiment, the anode is insoluble and made of lead, lead alloy, or titanium coated with platinum group metals (for example, Pt, Pd Ir, Ru) or oxides thereof. The cathode has a smooth surface to accept electrodeposited copper and in one embodiment, the surface is made of stainless steel, chrome-plated stainless steel, titanium, or titanium alloy.

In one embodiment, after the electrodeposited copper foil is formed on a rotating cylindrical cathode that is horizontally mounted, it is peeled off in the form of a thin sheet as the cathode rotates. After cutting the thin copper foil sheet to form one or more copper wires, the copper wire strands are shaped to have the desired cross-sectional shape and size.

In one embodiment, a copper foil is electrodeposited on a vertically-mounted cathode to form a thin cylindrical copper sheath around the cathode. The cylindrical copper sheath is scribed and cut to form a thin copper wire strand, which is peeled off on the cathode, and then subjected to a molding process to have the desired cross-sectional shape and size.

The flow rate of the electrolyte solution through the gap between the anode and the cathode is usually in the range of about 0.2 to about 3 m/sec, and in one embodiment, about 0.5 to about 2.5 m/sec, and in one embodiment, About 0.7 to about 2 meters per second. The concentration of free sulfuric acid contained in the electrolyte solution is usually in the range of about 10 to about 150 g/L, and in one embodiment, in the range of about 40 to about 110 g/L, and in one embodiment about 50. To about 90 grams per liter. The temperature of the electrolyte solution in the electroforming battery is usually in the range of about 40°C to about 80°C, and in one embodiment, about 45°C to about 75°C, and in one embodiment, about 50°C to about 50°C. About 70°C. Copper ion concentration (CaSO₄Included in) is usually in the range of about 50 to about 130 g/L, and in one embodiment, in the range of about 65 to about 115 g/L, and in one embodiment, in the range of about 80 to about 100 Within the range of grams/liter. The current density is critical and is in the range of about 500 to 2000 amperes per square foot, and in one embodiment, in the range of about 500 to about 1700 amperes per square foot, and in another embodiment, in the range of about Within the range of 600 to about 1400 amperes per square foot.

In one embodiment, a vertically mounted cathode is used to electrodeposit copper. The cathode rotates at a tangential speed of up to about 400 m/s, and in one embodiment at a tangential speed of about 10 to about 175 m/s Rotation is about 50 to about 75 meters per second in one embodiment, and 60 to about 70 meters per second in another embodiment. In one embodiment, the electrolyte solution flows upward between the cathode and the anode, which are vertically mounted, and the flow rate is about 0.1 to about 10 m/au, and in one embodiment, it is 1 to about 4 m/sec. , And in an embodiment, it is in the range of about 2 to about 3 meters per second.

The level of undesirable ion (other than chloride ions) contained in the electrolyte solution is generally less than about 10 g/L, and in one embodiment is in the range of about 0.2 to about 5 g/L, and in one embodiment In the range of about 0.4 to about 2 grams per liter. These impurities include phosphate, arsenic, zinc, tin, and undesirable organic impurities.

The concentration of free chloride ions contained in the electrolyte solution in operation is critical and preferably zero, but in practice it is in the range of up to about 5 ppm, and in one embodiment, up to about 3 ppm. In the examples, it is in the range up to about 1 ppm. The chloride ion concentration may be less than about 0.5 ppm, and in one embodiment, less than about 0.2 ppm, in one embodiment, less than about 0.1 ppm, and in one embodiment, less than about 0.05 ppm. Chloride ions can be added to the electrolytic solution in the form of HCL, NaCl or other species containing free chloride ions, but the concentration of these chloride ions must be maintained at the aforementioned level. The term "electrolyte solution in operation" is used here to refer to the electrolyte solution after entering the electroforming cell in operation. Methods for measuring the low chloride ion concentration in the electrolyte solution include the use of nephelometric turbidimetry and agents that can form insoluble precipitates with chloride ions. The turbidity meter can be used to quantitatively analyze the chloride ion content in samples as low as 0.01 ppm.

What is important is that the concentration of the organic additives in the electrolyte solution should be kept within the final range of up to about 0.2 ppm, and in one embodiment, up to about 0.1 ppm. In one embodiment, no organic additive is added, so the concentration of the organic additive is zero. When organic additives are used, they can be one or more gelatins. The gelatin used in the present invention is a homogeneous mixture of water-soluble proteins derived from gelatin. Animal glue is the preferred gelatin. The organic additives can also be selected from the following components: saccharin, caffeine, molasses, guar gum, acacia, thiourea, polyalkylene glycol (e.g. polyethylene glycol, polypropylene glycol, polyblack propylene glycol, Etc.), dithiothreitol, amino acids (such as proline, hydroxyproline, cysteine, etc.), acrylamide, propyl sulfide sulfate, tetraethylthiuram disulfide , Alkylene oxide (for example, ethylene oxide, propylene oxide, etc.), sulfane sulfonate, thioamine disulfide methionyl, or lower derivatives or mixtures of two or more.

The copper foil produced in the electroformed battery is a copper foil that can be annealed at a low temperature. In one embodiment, before being converted into copper wires, these copper foils are heat-treated or annealed at a sufficient temperature and a certain period of time to induce stress relaxation and increase fatigue ductility. The heat treatment temperature is usually in the range of about 120°C to about 400°C, and in one embodiment, in the range of about 140°C to about 300°C, and in one embodiment, in the range of about 160°C to about 250°C. The duration of the heat treatment depends on the special method used for the heat treatment. For example, one or more of the following methods can be used for heat treatment: in an air oven, in an inert air oven, in a vacuum, using radiation, and/or direct contact. In addition, the foil strip can be heated by resistance. Heat in a laminator or post-baking after laminating for heat treatment. It is important that the heat treatment time at a specific temperature is long enough so that the crystal structure, defects and dislocations of the copper foil can complete their transformation. For example, a large number of foils need a relatively long heat treatment time in a large batch oven, mainly heating the inner roll on the oven roll and the air trapped between the rolls. On the contrary, the continuous heat treatment requires a relatively short time because it only needs to heat the soap copper foil into the oven to a specific temperature. Generally, the heat treatment time is about 0.001 to about 24 hours, and in one embodiment, about 0.01 to about 6 hours, and in one embodiment, about 0.03 to about 3 hours.

In one embodiment, a rotating cathode is used, and as the cathode rotates, the copper foil is peeled from the cathode. Then use one or several cutting steps to cut the foil to form a plurality of copper strands or copper strips with a cross-section that is nearly rectangular. In one embodiment, two sequential cutting steps are used. In one embodiment, the thickness of the copper foil is in the range of about 0.001 to about 0.050, or about -.004 to about 0.010 inches. The foil is cut or strands with a width of about 0.25 to about 1 inch, or about 0.3 to about 0.7 inches, or about 0.5 inches, and then these strands are cut to have a width of about 1 to about 3 of the thickness of the foil. In one embodiment, the ratio of width to thickness is about 1.5:1 to about 2:1. In one embodiment, a 60 oz foil is cut into strands with a cross section of about 0.008×0.250 inches, and then cut into strands with a cross section of about 0.008×0.012 inches. The strands are then rolled or drawn to make the strands have the desired cross-sectional shape and size.

In one embodiment, copper is electrodeposited on a rotating cathode to become a copper foil in the form of a cylindrical aperture until the thickness of the copper foil attached to the cathode is about 0.005 to about 0.50, or about 0.010 to about 0.030, or about Up to 0.020 inches. Then the electrodeposition is interrupted and the copper surface is washed and dried. After the copper foil is beaten into thin copper strands with a scribing cutter, it is peeled off from the cathode. The scribing machine scribes along the long axis of the cathode when the cathode rotates. The scribing machine preferably cuts the copper foil to within about 0.001 inches of the cathode surface. The width of the cut copper strands is about 0.005 to about 0.050 inches, or about 0.010 to about 0.030 inches, or about 0.020 inches in one embodiment. In one embodiment, the copper strands have a square or substantially square cross-section with a size of about 0.005×0.005 inches to about 0.050×0.050 inches, or about 0.010×0.010 inches to about 0.030×0.030 inches, or about 0.020 inches. ×0.020 inch. Then the copper strands are rolled or drawn to have the desired cross-section and size.

In one embodiment, one or a series of Turks head forming mills are used to roll the copper wire strands, wherein in each forming mill, the wire strands are drawn through two pairs of relatively firmly arranged forming Between the rolls. In one embodiment, these rolls are all dented to produce shapes with rounded edges (for example, rectangles, squares, etc.). It is also possible to use a powered Turk head mill in which the rollers are driven. The speed of the Turk head mill may be about 100 to about 5000 feet/minute, and in one embodiment, about 300 to about 1500 feet/minute, and in one embodiment, about 600 feet/minute.

In one embodiment, the copper wire strands are passed through three Turk head rolling mills in order to convert the wire with a rectangular cross-section into a wire with a square cross-section. In the first rolling mill, the strands were rolled from a 0.005×0.010 inch cross section to a 0.0052×0.0088 inch cross section. In the second rolling mill, the strands were rolled from a 0.0052×0.0088 inch cross section to a 0.0054×.0.0070 inch cross section. In the third rolling mill, the strands were rolled from a cross section of 0.0054×0.0070 inches to a cross section of 0.0056×0.0056 inches.

In one embodiment, the strands are passed through two Turk head rolling mills in sequence. In the first rolling mill, the strands are rolled from a 0.00850.010 inch cross section to 0.0087 × 0.0093 inch cross section to 0.0090 × 0.0090. Inch cross section.

The copper wire strands can be cleaned using known chemical, mechanical or electropolishing techniques. In one embodiment, the copper wire strands cut from the copper foil or scribed and stripped from the cathode are cleaned with their chemical, electro-polishing or mechanical techniques before proceeding to a Turk mill for further shaping. . Chemical cleaning can be accomplished by passing the wire through an etching or pickling bath of nitric acid or thermal (e.g., about 25°C to 70°C) sulfuric acid. Electropolishing can be accomplished through the use of electric current and sulfuric acid. Mechanical cleaning is accomplished by removing burrs or similar rough parts on the surface of the copper wire using a brush or the like. In one embodiment, the wire is degreased with a caustic soda solution, washed, and rinsed with water. , Use hot (for example, about 35 °C) sulfuric acid pickling, electropolishing with sulfuric acid, rinse with water and dry.

In one embodiment, the copper wire strands have a relatively short length (for example, about 500 to about 5000 feet, and in one embodiment, about 1000 to about 3000 feet, and in one embodiment, about 2000 feet), These strands are welded to other strands made in a similar manner using known techniques (for example, punch welding) to produce strands with a relatively long length (for example, a length of more than about 100,000 feet, or more than about 100,000 feet). 200,000 feet up to a length of about 1,000,000 or more).

In one embodiment, the copper wire strands are drawn through a die to make the wire strands have a circular cross-section. The die can be shaped (for example, square, oval, rectangular, etc.) a row of round pass die (Shaped-to-round pass die), in which the incoming strands are in contact with the pull cone along the plane position Die head, and come out of the die head along the plane position. The included die angle, in one embodiment, is pure 8, 12, 16, 24 or other angles known in the art. In one embodiment, before drawing, these strands are cleaned and welded (as discussed above). In one embodiment, a wire strand having a square cross-section of 0.0056×0.0056 inches is drawn through a die in a single pass so that the copper wire has a circular cross-section and a cross-sectional diameter of 0.0056 inches (AWG 35). After that, the copper wire can be drawn through other cross heads to reduce its diameter.

Generally, the copper wire can have any cross-sectional shape that is customarily available. These include those illustrated in Figure 3-20. These include circular cross-sections (Figure 3), squares (Figure 57), squares (Figure 4), flat shapes (Figure 8), flat shapes with rib-like protrusions (Figure 18), stadium shapes (Figure 6), and more Angular (Figure 13-16), cross (Figure 9, 11, 12 and 19), star (Figure 10), semicircle (Figure 17), oval (Figure 20), etc. The edges of these shapes can be sharp (e.g., Figures 4, 5, 13-16), or rounded (e.g., Figures 6-9, 11, and 12). These copper wires can be formed by one or a series of Turk mills to produce the desired shape and size. The cross-sectional diameter or main dimension is in the range of about 0.0002 to about 0.02 inches, and in one embodiment, about 0.001 to about 0.01 inches, and in one embodiment, about 0.001 to about 0.005 inches.

In one embodiment, the copper wire has a circular cross-section and its diameter is in the range of about 0.0002 to about 0.02 inches, and in one embodiment, the diameter is about 0.001 to about 0.01 inches, and in one embodiment The medium is about 0.001 to about 0.005 inches.

In one embodiment, the copper wire has a circular cross-section and its diameter is in the range of about 0.0002 to about 0.02 inches, and in one embodiment, the diameter is about 0.001 to about 0.01 inches, and in one embodiment The medium is about 0.001 to about 0.005 inches.

In one embodiment, the copper wire is coated with one or more of the following paints:<tables><img file="TW336325B_D0002.tif" /></tables>(4) Tin ASTM B33

The application of these coatings is to (a) maintain the weldability required for the connection line application, (b) provide a barrier between the metal and the insulating material such as rubber, which can react with the metal and adhere to it (thus making it difficult to remove the insulator from The copper wire is stripped to make electrical connections) or (c) to prevent oxidation of the metal during high-temperature use.

Tin-lead alloy paint and about tin paint are the most commonly used; nickel and silver are used for specialized applications and high-temperature applications.

The copper wire can be coated by hot dipping in a molten metal bath, electroplating or cladding. In one embodiment, a continuous process is used: it can be applied "on line" followed by a wire drawing operation.

Strands can be made by twisting or braiding several wires together to form a flexible cable. For a given current carrying capacity, different deflection can be achieved by changing the number, size and arrangement of individual wires. Solid wires, concentric round strands, rope strands and bundled strands can provide incremental deflection; in the last three categories, the use of a large number of thinner wires can produce greater deflection.

Stranded wires and cables can be made on machines called "bunchers" or "stranders". Use customary bunchers to pattern small diameter wires (34 AWG up to 10 AWG). Individual threads are discharged from the spool next to the equipment and passed through the spindle arm rotating around the winding spool to tighten the threads. The rotation speed of the arm relative to the winding speed can control the length of lay in the bundle. For small portable flexible cables, individual wires are usually 30 to 44 AWG, and there can be as many as 30,000 wires in each cable.

A tubular wood gatherer with up to 18 pay-off reels can be used inside the unit. The thread is released from each spool in the form of keeping it in the horizontal plane, guided along a tubular space and twisted with other threads through the rotation of the empty tube. At the take-up end, the strands pass through a closed die to form the final bundle configuration. The completed strand is wound on a bobbin that is also held in the machine.

In one embodiment, the wire is insulated or coated or covered. There are three types of insulation or jacket materials that can be used. They are polymers, enamel, and paper-and-oil.

In one embodiment, the polymerization used is polyvinyl chloride (PVC), polyethylene, ethylene propylene rubber (EPR). Silicone rubber, polytetrafluoroethylene (PTFE) and fluorinated ethylene propylene (FEP). When durability is of the utmost importance, for example, parachute ropes used for loading spacecraft, use polyamide coatings. In addition, natural rubber can be used. In situations where good flexibility must be maintained, such as welding or mining ropes, synthetic rubber can be used.

There are many kinds of PVC can be used. They include several types with flame resistance. PVC has good dielectric strength and flexibility, and is particularly useful because it is one of the least expensive conventional insulation and jacket materials. It is mainly used for communication wires, control cables, building wires and low-voltage cables. PVC insulation is often selected for applications that require continuous operation at low temperatures up to about 75°C.

Polyethylene can be used for those who need better electrical properties because of its low and stable dielectric constant. It can resist abrasion and solvents, and it is mainly used for connecting wires, communication wires and high-voltage cables. Cross-linked polyethylene (XLPE) made by adding organic peroxide to polyethylene and vulcanizing the mixture can obtain better heat resistance, better mechanical properties, better aging characteristics, and will not cause environmental stress. crack. Special ingredients can provide flame resistance in cross-linked polyethylene. Its general maximum continuous operating temperature is about 90°C.

PTEF and FEP can be used to insulate jet wires, electronic equipment wires and special-grade control cables. Among them, heat resistance, solvent resistance and high reliability are all important. These cables can be operated at temperatures up to about 250°C.

These polymer compounds can be applied to the wires by using extrusion methods. An extruder is a machine that transforms thermoplastic polymer pellets or powder into continuous coatings. The insulating ingredients are loaded in the hopper and then fed into the long and heated room. A continuously rotating screw feeds the pellets into the hot zone, where the polymer softens and becomes fluid. At the end of the chamber, the molten ingredients are forced to pass from the small die on the moving line through the die opening together with the line. When the insulator-added wire leaves the extruder, it is cooled by water and then wound on the bobbin. The wires covered with ERP and XLPE are best passed through a vulcanization chamber before cooling to complete the cross-linking process.

Film-coated wires, usually thin magnetic wires, are generally made of copper wires coated with a thin flexible enamel film. These insulated copper wires are used in electromagnetic coils of electrical devices and must be able to withstand high damaging voltages. The temperature grade ranges from about 105°C to about 220°C, depending on the composition of the enamel paint. Available enamels are those based on polyvinyl acetal, polyester and epoxy resin.

The equipment used for enamel coating of wires is designed to insulate a large number of wires at the same time. In one embodiment, the wire is passed through an enamel coater, and a liquid enamel with a controlled thickness is deposited on the wire. The wires are then moved through a series of ovens to harden the coating, and the finished wires are collected on spools. To create a heavy enamel coating, it may be necessary to pass the wires through the system several times. Powder coating method can also be used. This type of method can avoid the solvent emission that is characteristic of hardened traditional enamel paints, thus making it easier for manufacturers to comply with OSHA and EPA standards. Electrostatic sprayers, fluidized bodies, etc. can be used to apply these powder coatings.

So far referring to the illustrated embodiment, and first, Figure 1 shows a method of manufacturing a copper wire, in which copper is electrodeposited on a cathode to form a thin cylindrical copper sheath that covers the cathode; then the The cylindrical copper sheath is used to form a thin copper wire strand, which is stripped from the cathode and subjected to a molding process to make the wire have the desired cross-sectional shape and size (for example, a circular cross-section with a cross-sectional diameter of About 0.0002 to about 0.02 inches). The device used in this method includes an electroformed cell 10 containing a container 12, a cylindrical anode 14 in a vertical device, and a cathode 16 in a vertical device. The container 12 contains an electrolyte solution 18. In addition, it also includes a scribing cutter 20, a Turk head forming mill 22, a die 24 and a spool 26. The cathode 16 is shown as a virtual image immersed in the electrolyte 18 contained in the container 12. When the cathode 16 is immersed in the container 12, the anode 14 and the cathode 16 are coaxially arranged, and the cathode 16 is installed in the anode 14. The distance between the anode 14 and the cathode 16 is in the range of about 0.0 to about 2 cm in one embodiment. The anode 16 runs at a rate of up to about 400 m/sec, in one embodiment about 10 to about 175 m/sec, in one embodiment, about 50 to 75 m/sec, and in one embodiment, 60 to about 70 m/sec. Tangent speed rotation in the range of m/s. The electrolyte solution 18 flows upward at a velocity in the range of about 0.1 to about 10 meters/second, and in one embodiment, about 1 to about 4 meters/second, and in one embodiment, about 2 to about 3 meters/second. Between the cathode 16 and the anode 14.

A voltage is applied between the anode 14 and the cathode 16 to promote the electrodeposition of copper on the cathode. In one embodiment, the current used is a direct current, and in one embodiment, it is an alternating current with a direct current bias. The copper ions in the electrolyte 18 obtain electrons on the peripheral surface 17 of the cathode 16, and the metal copper is plated out in the form of a cylindrical sheath 28 surrounding the surface 17 of the cathode 16. The electrodeposition of copper on the cathode 16 will continue until the thickness of the copper sheath 28 reaches a desired level, for example, about 0.005 to about 0.050 inches. Then stop the electrodeposition. Remove the cathode from the container 12. The copper sheath 28 is washed and dried. The scoring cutter 20 is then activated to cut the copper sheath 28 into thin continuous strands 30. The scribing cutter 20 moves along the spiral 32 when the cathode 16 is driven by the supporting and driving element 34 to rotate about its central axis. The rotating blade 35 cuts the copper sheath 28 to within about 0.001 inches of the surface 17 of the cathode 16. After that, the wire strand 36 having a rectangular cross-section is peeled off from the cathode 16 and advanced through the Turk head rolling mill 22, where it is rolled to transform the cross-sectional shape of the wire strand into a square. The wire is then drawn through the die 24, where the cross-sectional shape is transformed into a circular cross-section. After that, the thread is wound on the spool 26.

This procedure will deplete the copper ions and organic additives in the electrolyte solution 18 if they are used. These ingredients must be supplemented continuously. The electrolyte solution 18 is extracted from the container 12, flows through the line 40 and circulates through the filter 42, the macerator 44 and the filter 46, and then leads to the container 12 through the line 48. The sulfuric acid is led from the container 50 to the macerator 44 through the line 52. The copper system from the source 54 is guided into the macerator 44 along a route 56. In one embodiment, the copper system introduced into the macerator 44 is in the form of copper pellets, copper wire scraps, copper oxide or recycled copper. In the macerator 44, sulfuric acid and air dissolve copper to form a solution containing copper ions.

When the organic additives are useful, they are added to the circulating solution in the line 40 from the container 58 via the line 60, or added from the container 64 to the circulating solution in the line 48 via the line 62. The addition rate of these organic additives is within the range of up to about 0.1 mg/min/KA in one embodiment, and up to about 0.07 mg/min/KA in one embodiment. In one embodiment, no organic additives are added.

The illustrated embodiment disclosed in FIG. 2 is the same as the embodiment disclosed in FIG. 1 except for the following: the electroformed battery 10 in FIG. 1 is replaced by the electroformed battery 110 in FIG. 2; the container 12 is The container 112 is replaced; the cylindrical anode 14 is replaced by a curved anode 14; the vertically installed cylindrical cathode 16 is replaced by a horizontally installed cylindrical cathode 116; and the scribe cutter 20, spiral 32 and support The driving element 34 is replaced by the roller 118 and the longitudinal breaker 120.

In the electroplating battery 110, a voltage is applied between the anode 114 and the cathode 116 to promote the electrodeposition of copper on the cathode. In one embodiment, the current used is direct current, and in another embodiment, alternating current with a direct current bias is used. The copper ions in the electrolyte solution acquire electrons on the peripheral surface 117 of the cathode 116, whereby metallic copper is plated on the peripheral surface 117 in the form of a copper foil layer. The cathode is rotated around its axis and the foil layer is extracted from the cathode surface 117 in the form of a continuous metal sheet 122. The electrolyte is circulated and replenished in the same manner as described above for the embodiment disclosed in FIG. 1.

After the copper foil 122 is peeled off from the cathode 116, it passes through the roller 118 and passes through the slitter 120, where it is split into a plurality of continuous strands 124 having a rectangular or substantially rectangular cross-sectional shape. In one embodiment, the copper foil 122 is advanced to the slitter 120 in a continuous process. In one embodiment, after the copper foil is peeled off from the cathode 116, it is stored in the form of a roll, and is introduced through the slitter only later. The rectangular strands 124 advance from the slitter 120 through the Turk head mill 22, where they are rolled into strands 126 having a square cross-section. The strands 126 are then drawn through the die 24, where they are drawn to form a copper wire 128 having a circular cross-section. Finally, the copper wire 128 is wound on the spool 26.

The following examples are proposed to illustrate the purpose of the present invention. Unless otherwise indicated, in the following examples and throughout the specification and the scope of the patent application, all parts and percentages are by weight, all temperatures are in degrees Celsius, and all pressures are atmospheric.

<u style="single">Example 1</u>

The foil sample in the following table is obtained by using a copper ion concentration of 105 g/l, a free sulfuric acid concentration of 80 g/l &lt;a chloride ion concentration of 0.1 ppm, an addition rate of animal glue of 0.07 mg/min/1,000 and Produced by an electrolyte solution with a current density of 1100 amps/square foot. These samples have been heat-treated or not heat-treated as indicated below. The number of bending cycles was measured using a 2 mm mandrel attached to the foil with a load of 84 grams in the transverse direction. The foil sample has a nominal weight of 1 oz/square foot. The fatigue ductility is calculated using equation (1).

<tables><img file="TW336325B_D0003.tif" /></tables><tables><img file="TW336325B_D0004.tif" /></tables>

Figures 2 and 3 are photomicrographs of cross-sections of Examples 5 and 8 taken at 800× magnification, respectively. These photomicrographs. These photomicrographs revealed a substantially uniform and non-directional grain structure with almost no columnar grains. After cutting these foil samples, they are advanced through a Turk head rolling mill, and then drawn through a die to form a line sample with a circular cross-section.

<u style="single">Example 2</u>

The foil samples in the following table are the electrolyte solution containing 103 g/L copper ion concentration, 60 g/L free sulfuric acid concentration, 2.8 ppm chloride ion concentration, and zero organic additive concentration, that is, no organic additive is added. Made. The number of bending cycles was measured using a 2 mm diameter mandrel with a load of 84 grams transversely connected to the foil sample. The foil sample has a nominal weight of 1 oz/square foot. All inspections are carried out in horizontal direction according to IPC MF-150F.

<tables><img file="TW336325B_D0005.tif" /></tables><tables><img file="TW336325B_D0006.tif" /></tables><tables><img file="TW336325B_D0007.tif" /></tables>After cutting these foil samples, they are sent to a Turk head rolling mill and a die wire is drawn to form a wire pattern with a circular cross-section.

<u style="single">Example 3</u>

The foil sample contained in the table below has a nominal weight of 1 oz/square foot. The annealed samples were heat treated at 200-250°C for 30 minutes. The low-temperature annealing foil sample is heat-treated at 177°C for 15 minutes, which is the cycle required for the 8th grade copper foil using IPC MF 150F. The samples were inspected in the transverse machine direction. The number of bending cycles is measured by using a mandrel with a diameter of 2 mm and a load of 84 grams transversely connected to the foil sample.

<tables><img file="TW336325B_D0008.tif" /></tables><tables><img file="TW336325B_D0009.tif" /></tables>

After cutting these foil samples, they are sent through a Turk head rolling mill and then drawn through a die to form a wire sample with a circular cross-section.

<u style="single">Example 4</u>

The electrodeposited copper foil having a width of 84" inches, a thickness of 0.058" inches, and a length of 600 feet, as disclosed in Sample No. 5 of Example 1, above, was collected on a roll. Use a series of slitters to reduce the foil from an original width of 84" to approximately a 0.25" wide tape. The first slitter reduces the width from 84" to 24", the second slitter reduces the width from 24" to 2", and the third reduces 2" to 0.25 inches. The 0.25" belt is further Split into 0.012" wide bands. These bands, or cut and cut copper wires, have a cross section of 0.008×0.012". These copper wires are prepared for metal forming and forming operations. These include degreasing washing, water rinsing, pickling, electropolishing, water rinsing, and drying. The single strands are welded together and wound on a spool for release to the next processing step. Clean the strands and remove gouges. Then use a combination of rollers and drawing die to shape them into a circular chess section. The first pass uses a miniaturized Turk head forming mill to reduce the 0.012" side edge to about 0.010-0.11". The next pass passes through the second Turk head rolling mill, where this size is further compressed into 0.008-0.010", and the entire cross section becomes a square. Both passes are large compressed relative to the above size, and their transverse dimensions (perpendicular to The cross-sectional dimension in the compression direction) increases and the length of the wire increases. Each of its passes rounds the edge. Then the wire passes through a drawing die, where it is rounded and stretched to have 0.00795", AWG 32 The diameter.

Although the present invention has been explained in relation to its preferred embodiments, those skilled in the art can understand various modifications of the present invention after reading this specification. Therefore, it should be understood that the present invention disclosed in this article intends to cover their modifications so as to be included in the scope of the appended patent application.