A high-strength alloy conductor, drag chain cable and preparation method thereof

Abstract

The invention discloses a high-strength alloy wire, a drag chain cable and a preparation method thereof. The Vickers hardness of the copper alloy wire body is 185-200 HV 0.3 , tensile strength of 515-550MPa, elongation at break greater than 7.5%, elastic modulus of 128-135GPa, conductivity greater than 70%IACS; by using silver, nickel, tin, niobium, and copper raw materials, a copper alloy body with high strength, high elasticity, bending resistance, and fatigue resistance is prepared as a conductor. Through the optimization and control of flux and hot-dip tinning process, a tin coating with excellent bonding strength is prepared on the copper alloy conductor; it can withstand repeated bending and twisting tests, and the tin coating does not fall off or crack. The anti-bending performance of the drag chain cable prepared in this way is greatly improved, which can meet the application needs of industry equipment.

Description

Technical Field

[0001] The invention relates to the field of drag chain cables, and in particular to a high-strength alloy conductor, a drag chain cable and a preparation method thereof. Background Art

[0002] Copper and copper alloys are the third most used metals in modern industry and are widely used in electronics, communications, military and other industries. Tinned copper alloy wire refers to a copper alloy wire with a tin metal layer prepared on the surface to prevent the copper alloy from oxidizing. However, due to the particularity of the application environment, in addition to the most basic conductivity and corrosion resistance, the copper alloy wire connections need to be bent frequently, so the requirements for the bending resistance of tinned copper alloy wires are higher, and excellent elastic properties, fatigue resistance and good strength are also required.

[0003] Existing tin-plated copper alloy wires are usually prepared by directly depositing a tin layer on the surface of the copper alloy wire body through chemical plating, electroplating and other processes.

[0004] Chinese patent CN 113118234 A discloses a production process for tin-plated alloy wire for medical equipment. The alloy matrix is ​​smelted in a smelting furnace, and the added refining agent is prepared by silicon powder, rare earth lanthanum powder and modified bentonite. The rare earth lanthanum has strong activity and the silicon powder has excellent fluidity, thereby assisting the modified bentonite to be prepared with the alloy matrix and improving the effect of the modified bentonite with the alloy matrix. The bentonite is calcined and modified in a calcining furnace, and the cobalt sulfate in the soaking agent is infiltrated into the bentonite layer, and then dispersed and activated to improve the dispersibility of the bentonite in the alloy matrix. In the electroplating, the electroplated tin is inserted into the bentonite layer, thereby improving the stability of the electroplated tin and improving the corrosion resistance of the alloy wire. However, it does not involve aspects such as elasticity, fatigue resistance and strength.

[0005] Copper alloy is also the conductor of the drag chain cable. The drag chain cable needs excellent flexibility and resilience, which requires the alloy wire as the conductor to not fail under a large number of bends. With the development of the communications industry, the requirements for the bending resistance of the alloy wire in the drag chain cable are higher, and excellent elasticity, fatigue resistance and good strength are also required.

[0006] Therefore, seeking new process improvements to prepare tin-plated copper alloy wires remains a research focus in the industry. Summary of the invention

[0007] In view of the defects and needs in the prior art, the present invention provides a high-strength alloy wire, a drag chain cable and a preparation method thereof. By studying and improving the preparation of the copper alloy copper wire body and the tinning process, a high-strength alloy wire is prepared, which has high strength, high elasticity, excellent bending resistance and fatigue resistance, and is suitable for the preparation of drag chain cables.

[0008] In order to achieve the purpose of the present invention, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides a method for preparing a high-strength alloy wire, comprising the following steps:

[0010] (1) According to the mass fraction ratio, 5-8% silver, 3-4% nickel, 1-2% tin, 0.5-1% niobium and the balance electrolytic copper raw materials are placed in a melting crucible and heated to 350-400° C. for preheating for 10-20 minutes.

[0011] (2) Turn on the vacuum system to evacuate the closed melting crucible until the vacuum degree is less than 2.0×10 -3 Pa, and then high-purity argon is introduced; the power is turned on again to heat to a temperature of 1280-1320°C and kept warm for 30-40 minutes, and then poured into a cylindrical casting mold and cooled to room temperature to obtain a copper alloy ingot.

[0012] (3) The copper alloy ingot is rolled into a copper alloy rod by a continuous casting machine, drawn into a copper alloy wire by a wire drawing machine, and annealed to obtain a copper alloy conductor.

[0013] (4) The copper alloy wire is passed through a flux tank, a molten tin tank, a negative pressure chamber with a conical opening, a cooling device, and a winding device by using a traction mechanism to obtain a tin-plated high-strength alloy wire.

[0014] The present application preheats the raw materials and the smelting dry pot before smelting to dry them and thus avoid residual water vapor in the smelting process that affects the quality of the alloy ingot.

[0015] Furthermore, in step (2), during the heating process, the gas pressure in the crucible is 0.6-0.8 MPa and the heating rate is 30-40°C / min; the cooling is carried out in an atmosphere with an argon flow rate of 200-300 sccm, and the cooling rate is 15-20°C / min.

[0016] Too high a cooling rate can easily lead to severe dendrite segregation inside the copper alloy, while too low a cooling rate can easily cause copper to crystallize too quickly, making it difficult to form a uniform internal structure with other components.

[0017] Furthermore, in step (3), according to the application situation, the parameters of the wire drawing machine can be controlled to produce copper alloy wires of different sizes; the diameter of the copper alloy wire can be listed as 0.1 to 2.0 mm, optionally 0.1 to 1.0 mm, or optionally 0.2 to 0.5 mm.

[0018] Furthermore, in step (3), the annealing temperature is 600-800° C. and the annealing time is 7-10 hours. The annealing treatment can make the atoms in the copper alloy diffuse uniformly and further eliminate the dendrite segregation during the pouring and cooling process.

[0019] Furthermore, in step (4), the flux composition is: 60-80 g / L stannous chloride, 40-50 g / L adipic acid, 1-5 g / L lanthanum chloride, 0.3-0.5 g / L alkylphenol polyoxyethylene ether, and the balance anhydrous ethanol; the flux temperature is 40-50°C; and the speed of the copper alloy wire is 1.5-2.0 m / min. The flux composition can effectively remove the oxide layer on the surface of the copper alloy, reduce the stress between the tinned layer and the copper alloy body, and avoid pinhole defects.

[0020] Furthermore, in step (4), the temperature of the molten tin solution is 320-350°C.

[0021] Furthermore, in step (4), the diameter of the tapered outer opening corresponds to the diameter of the copper alloy wire, and preferably, the diameter of the tapered outer opening is set according to the thickness of the coating. In the present application, when the copper alloy wire passes through the tapered outer opening, the molten tin attached thereto will make the thickness of the tin coating more uniform and the tin coating more dense due to the effect of the opening, thereby increasing the adhesion between the tin coating and the copper alloy wire body. On the other hand, the pressure of the negative pressure chamber is 0.1 to 0.3 MPa, which can effectively prevent the generation of tiny bubbles during the condensation of the molten tin.

[0022] In a second aspect, the present invention provides a high-strength alloy wire prepared by the above preparation method, comprising a copper alloy wire body and a tin plating layer; the thickness of the tin plating layer is 100 to 500 μm.

[0023] Furthermore, the Vickers hardness of the high-strength alloy wire is 185-200 HV 0.3 , tensile strength of 515-550MPa, elongation at break greater than 7.5%, elastic modulus of 128-135GPa, and electrical conductivity greater than 70%IACS.

[0024] In a third aspect, the present invention provides a drag chain cable prepared using the above-mentioned high-strength alloy wire as a conductor, wherein the conductor is composed of 6 to 8 strands of high-strength alloy wires concentrically twisted together, and the diameter of the high-strength alloy wire is 0.07 to 0.09 mm.

[0025] Furthermore, the drag chain cable also includes an insulating layer, an inner sheath, a shield and an outer sheath, and a central reinforcement member.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) The present application adopts silver, nickel, tin, niobium and copper raw materials to prepare a copper alloy body with high strength, high elasticity, bending resistance and fatigue resistance as a conductor; it can meet the requirements of the conductor.

[0028] (2) Through the optimization and control of flux and hot-dip tinning process, a tin coating with excellent bonding strength was prepared on the copper alloy wire; it was able to withstand repeated bending and twisting tests without any detachment or cracking of the tin coating.

[0029] (3) High-strength alloy conductors can be used in drag chain cables. The bending resistance of drag chain cables is greatly improved, which can meet the application requirements of industry equipment. DETAILED DESCRIPTION

[0030] The present invention is described in detail by way of examples. The following examples are implemented on the premise of the technical solution of the present invention, and provide detailed implementation methods and specific operation processes, but the protection scope of the present invention is not limited to the following examples.

[0031] Example 1

[0032] A method for preparing a high-strength alloy wire comprises the following steps:

[0033] (1) According to the mass fraction ratio, 5% silver, 3% nickel, 1% tin, 0.5% niobium and the balance electrolytic copper raw materials are placed in a melting crucible and heated to 350° C. for 20 minutes.

[0034] (2) Turn on the vacuum system to evacuate the closed melting crucible until the vacuum degree is less than 2.0×10 -3 Pa, and then high-purity argon is introduced; the power is turned on again to heat to a temperature of 1280°C and keep warm for 30 minutes, then poured into a cylindrical casting mold and cooled to room temperature to obtain a copper alloy ingot; wherein: the gas pressure in the crucible during the heating process is 0.6MPa and the heating rate is 30°C / min; cooling is carried out in an atmosphere with an argon flow rate of 200sccm, and the cooling rate is 15°C / min.

[0035] (3) The copper alloy ingot is rolled into a copper alloy rod by a continuous casting machine, drawn into a copper alloy wire by a wire drawing machine, and annealed to obtain a copper alloy conductor; wherein the annealing temperature is 600° C. and the annealing time is 7 hours.

[0036] (4) A traction mechanism is used to pass the copper alloy wire through a flux tank, a molten tin tank, a negative pressure chamber with a conical opening, a cooling device, and a reel to obtain a tinned copper alloy wire; the flux composition is: 60 g / L stannous chloride, 40 g / L adipic acid, 1 g / L lanthanum chloride, 0.3 g / L alkylphenol polyoxyethylene ether, and the balance is anhydrous ethanol; the flux temperature is 40°C; the speed of the copper alloy wire is 1.5 m / min; the temperature of the molten tin liquid is 320°C; and the pressure of the negative pressure chamber is 0.1 MPa.

[0037] Example 2

[0038] A method for preparing a high-strength alloy wire comprises the following steps:

[0039] (1) According to the mass fraction ratio, 8% silver, 4% nickel, 2% tin, 1% niobium and the balance electrolytic copper raw materials are placed in a melting crucible and heated to 400°C for preheating for 10 minutes.

[0040] (2) Turn on the vacuum system to evacuate the closed melting crucible until the vacuum degree is less than 2.0×10 -3 Pa, and then high-purity argon is introduced; the power is turned on again to heat to a temperature of 1320°C and keep warm for 40 minutes, then poured into a cylindrical casting mold and cooled to room temperature to obtain a copper alloy ingot; wherein: the gas pressure in the crucible during the heating process is 0.8MPa and the heating rate is 40°C / min; cooling is carried out in an atmosphere with an argon flow rate of 300sccm, and the cooling rate is 20°C / min.

[0041] (3) The copper alloy ingot is rolled into a copper alloy rod by a continuous casting machine, drawn into a copper alloy wire by a wire drawing machine, and annealed to obtain a copper alloy conductor; wherein the annealing temperature is 800° C. and the annealing time is 10 h.

[0042] (4) A traction mechanism is used to pass the copper alloy wire through a flux containing tank, a molten tin tank, a negative pressure chamber with a conical opening, a cooling device, and a reel to obtain a tinned copper alloy wire; the flux composition is: 80% stannous chloride, 50g / L adipic acid, 5g / L lanthanum chloride, 0.5g / L alkylphenol polyoxyethylene ether, and the balance is anhydrous ethanol; the flux temperature is 50°C; the speed of the copper alloy wire is 2.0m / min; the temperature of the molten tin liquid is 350°C; and the pressure of the negative pressure chamber is 0.3MPa.

[0043] Example 3

[0044] A method for preparing a high-strength alloy wire comprises the following steps:

[0045] (1) According to the mass fraction ratio, 6% silver, 3.5% nickel, 1.5% tin, 0.7% niobium and the balance electrolytic copper raw materials are placed in a melting crucible and heated to 380° C. for 15 minutes.

[0046] (2) Turn on the vacuum system to evacuate the closed melting crucible until the vacuum degree is less than 2.0×10 -3 Pa, and then high-purity argon is introduced; the power is turned on again to heat to a temperature of 1320°C and kept warm for 40 minutes, and then poured into a cylindrical casting mold and cooled to room temperature to obtain a copper alloy ingot; wherein: the gas pressure in the crucible during the heating process is 0.7MPa and the heating rate is 35°C / min; the cooling is carried out in an atmosphere with an argon flow rate of 250sccm, and the cooling rate is 17°C / min.

[0047] (3) The copper alloy ingot is rolled into a copper alloy rod by a continuous casting machine, drawn into a copper alloy wire by a wire drawing machine, and annealed to obtain a copper alloy conductor; wherein the annealing temperature is 700° C. and the annealing time is 8 h.

[0048] (4) A traction mechanism is used to pass the copper alloy wire through a flux tank, a molten tin tank, a negative pressure chamber with a conical opening, a cooling device, and a reel to obtain a tinned copper alloy wire; the flux composition is: 70% stannous chloride, 45g / L adipic acid, 35g / L lanthanum chloride, 0.4g / L alkylphenol polyoxyethylene ether, and the balance anhydrous ethanol; the flux temperature is 45°C; the speed of the copper alloy wire is 1.8m / min; the temperature of the molten tin liquid is 330°C; and the pressure of the negative pressure chamber is 0.2MPa.

[0049] Before the tinning step, the copper alloy wire obtained in step (3) of Examples 1 to 3 was cut to measure its relevant properties, and the measured and calculated data are recorded in Table 1. At the same time, the relevant properties of the obtained tinned high-strength alloy wire were tested, and the measured and calculated data are recorded in Table 2.

[0050] Table 1

[0051]

[0052]

[0053] It can be seen from the data in Table 1 that the copper alloy body prepared in the present application has high strength, high elastic modulus, and good electrical conductivity; the performance of the copper alloy is significantly improved.

[0054] Table 2

[0055]

[0056] It can be seen from the data in Table 2 that the bonding strength between the tin plating and the copper alloy prepared in the present application is as high as 20 MPa, indicating that the bonding between the two is firm; and no plating shedding was found after 500 bending tests; this also shows that the tin-plated copper alloy wire of the present application has excellent bending resistance and can meet high-frequency bending application scenarios.

[0057] The conductivity of the tinned copper alloy wire is lower than that of the copper alloy wire itself. This is because the conductivity of the tin plating layer is poor, resulting in a decrease in the overall conductivity.

[0058] The above implementation modes are only used to illustrate the present invention, but not to limit the present invention. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also belong to the scope of the present invention. The patent protection scope of the present invention should be defined by the claims.

Claims

1. A method for preparing a tinned copper alloy wire, characterized in that: The following steps are involved: (1) according to the mass fraction ratio, 5-8% silver, 3-4% nickel, 1-2% tin, 0.5-1% niobium, and the balance of electrolytic copper raw materials are placed in a melting crucible, and heated to 350-400° C. for preheating for 10-20 minutes; (2) Turn on the vacuum system to evacuate the closed melting crucible until the vacuum degree is less than 2.0×10 -3 Pa, and then high-purity argon is introduced; the power is turned on again to heat to a temperature of 1280-1320°C and kept warm for 30-40 minutes, and then poured into a cylindrical casting mold and cooled to room temperature to obtain a copper alloy ingot; (3) rolling the copper alloy ingot into a copper alloy rod, drawing it into a copper alloy wire by a wire drawing machine, and annealing it to obtain a copper alloy wire; (4) using a traction mechanism to pass the copper alloy wire through a flux holding tank, a molten tin liquid tank, a negative pressure chamber with a tapered opening, a cooling device, and a winding device to obtain a tinned copper alloy wire; In step (4), the soldering flux is composed of: 60-80 g / L stannous chloride, 40-50 g / L adipic acid, 1-5 g / L lanthanum chloride, 0.3-0.5 g / L alkylphenol polyoxyethylene ether, and the balance anhydrous ethanol; the soldering flux temperature is 40-50° C.; the speed of the copper alloy wire is 1.5-2.0 m / min; In step (4), the temperature of the molten tin liquid is 320-350° C.; In step (4), the pressure of the negative pressure chamber is 0.1-0.3 MPa.

2. The method for preparing the tinned copper alloy wire according to claim 1, characterized in that: In step (2), during the heating process, the gas pressure in the crucible is 0.6-0.8 MPa and the heating rate is 30-40°C / min; the cooling is carried out in an atmosphere with an argon flow rate of 200-300 sccm, and the cooling rate is 15-20°C / min.

3. The method for preparing the tinned copper alloy wire according to claim 1, characterized in that: In step (3), the annealing temperature is 600-800° C. and the annealing time is 7-10 hours.

4. A high-strength alloy wire, characterized in that: The high-strength alloy wire is prepared by the preparation method according to any one of claims 1 to 3, and the high-strength alloy wire comprises a copper alloy wire body and a tin plating layer; the thickness of the tin plating layer is 100 to 500 μm.

5. The tinned copper alloy wire according to claim 4, characterized in that: The Vickers hardness of the copper alloy wire body is 185-200 HV 0.3 , tensile strength of 515-550MPa, elongation at break greater than 7.5%, elastic modulus of 128-135GPa, and electrical conductivity greater than 70%IACS.

6. A drag chain cable prepared with the high-strength alloy wire according to any one of claims 4 to 5 as a conductor, characterized in that: The conductor is composed of 6 to 8 strands of high-strength alloy wires twisted concentrically, and the diameter of the high-strength alloy wire is 0.07 to 0.09 mm.

7. The drag chain cable according to claim 6, characterized in that: The drag chain cable also includes an insulation layer, an inner sheath, a shield and an outer sheath, and a central reinforcement member.

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