A high-temperature corrosion-resistant stranded conductor and its manufacturing method

Abstract

The present invention relates to the technical field of high-temperature conductors, and particularly to a high-temperature corrosion-resistant stranded conductor and a manufacturing method thereof. Among them, a high-temperature corrosion-resistant stranded conductor is composed of a plurality of composite wire filaments stranded together. The composite wire filament is composed of a highly conductive core wire and a high-temperature corrosion-resistant alloy wrapped around the outside of the core wire, enabling the stranded conductor to maintain strength and transmit signals in a high-temperature atmospheric environment of 1000 °C for a long time; the highly conductive core wire is copper or a copper alloy; by using a plurality of composite wires to form a stranded conductor through stranding, the composite wire is composed of a highly conductive core wire and a high-temperature corrosion-resistant alloy wrapped around the outside of the core wire, so that when the wire material works at a temperature of 600 °C to 1000 °C for a long time, it still maintains high strength, electrical conductivity and excellent anti-oxidation and corrosion characteristics, solving the technical problem that conventional conductors cannot work normally in a high-temperature environment in the prior art.

Description

Technical Field

[0001] The present invention relates to the technical field of high-temperature conductors, and in particular to a high-temperature corrosion-resistant stranded conductor and a manufacturing method thereof. Background Art

[0002] Conductors will be oxidized at high temperatures, and as the temperature rises to a certain range, the strength of the conductor drops sharply and the resistance increases. In a high-temperature environment, it is often required that the oxidation rate of the conductor is slow, otherwise the conductor will be corroded and broken. In some high-temperature atmospheric environments, the temperature even exceeds 1000°C, and the conductor also needs to play a role in conducting electricity. Therefore, it is necessary to solve the problems of high-temperature corrosion resistance, conductivity, and strength of the conductor at the same time.

[0003] Chinese Patent CN118155913B discloses a stranded conductor and a manufacturing method of a stranded wire that maintains high strength and high conductivity in a high-temperature environment, which relates to the technical field of high-temperature conductors. The stranded conductor is composed of several composite wire filaments twisted together. The composite wire includes a nickel-tantalum-tungsten core wire, a high-conductivity alloy tube wrapped outside the nickel-tantalum-tungsten core wire, and a coating layer provided outside the conductive alloy tube. By using several composite wires to twist into a stranded conductor, and the composite wire is composed of a nickel-tantalum-tungsten core wire, a high-conductivity alloy tube wrapped outside the nickel-tantalum-tungsten core wire, and a coating layer provided outside the conductive alloy tube, it is realized that when the wire works for a long time at a temperature of 600°C to 700°C, it still maintains high strength, conductivity, and fatigue resistance characteristics, and solves the problem that the current heat-resistant conductor has low conductivity or low strength in a high-temperature environment.

[0004] However, this technical solution is mainly applicable to working conditions where the conductor requires high conductivity and strength in a high-temperature environment below 600°C to 700°C. However, for high-temperature conditions above 700°C, this conductor cannot work properly. In particular, there is no conductor material available on the market that can still maintain good strength, signal transmission performance, and anti-oxidation and corrosion characteristics when working for a long time under high-temperature conditions of 800°C to 1000°C. Summary of the Invention

[0005] The purpose of the present invention is to provide a high-temperature corrosion-resistant stranded conductor for the deficiencies of the prior art. By using several composite wire filaments to twist into a stranded conductor, the composite wire filaments are composed of a highly conductive core wire and a high-temperature corrosion-resistant alloy wrapped outside the core wire, so that when the wire works for a long time at a high temperature of 600°C to 1000°C, it still maintains high strength, conductivity, signal transmission performance, and excellent anti-oxidation and corrosion characteristics, and solves the technical problem that conventional conductors cannot work properly in a high-temperature environment in the prior art.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A high-temperature corrosion-resistant stranded conductor, which is composed of several composite wire filaments stranded together. The composite wire filament is composed of a highly conductive core wire and a high-temperature corrosion-resistant alloy wrapped around the core wire, enabling the stranded conductor to maintain strength and transmit signals in a high-temperature atmospheric environment below 1000°C for a long time;

[0008] The highly conductive core wire is copper or a copper alloy;

[0009] The components of the high-temperature corrosion-resistant alloy are in a weight ratio of nickel 60% - 75%, chromium 10.0% - 20.0%, molybdenum 5% - 15%, the total amount of tantalum and niobium 0.5% - 10%, tungsten 0.5% - 10%, aluminum 2.0% - 7.0%, titanium 0.1% - 1.0%, iron 0.1% - 2.0%, and the balance is inevitable trace impurities, and the total weight of the impurities is not more than 0.5%, and the oxygen content is lower than 9 ppm.

[0010] As an improvement, the components of the high-temperature corrosion-resistant alloy are in a weight ratio of nickel 60% - 75%, chromium 10.0% - 20.0%, molybdenum 6% - 10%, tantalum 2% - 3%, niobium 1.5%, tungsten 4% - 5%, aluminum 2.0% - 7.0%, titanium 0.1% - 1.0%, iron 0.1% - 2.0%, and the balance is inevitable trace impurities, and the total weight of the impurities is not more than 0.5%, and the oxygen content is lower than 9 ppm.

[0011] As an improvement, the cross-sectional area of the core wire in the composite wire filament accounts for 20% - 50% of the total area.

[0012] As an improvement, the diameter of the composite wire filament is 0.08 - 0.5 mm.

[0013] As an improvement, the tensile strength of the composite wire filament at 20°C is greater than 400 MPa, the conductivity is greater than 20%, and the elongation is greater than 2%.

[0014] As an improvement, the comprehensive tensile strength of the composite wire filament under high-temperature working conditions: the tensile strength at 1000°C is not less than 50 MPa, the tensile strength at 900°C is not less than 80 MPa, the tensile strength at 800°C is not less than 150 MPa, and the tensile strength at 600 - 750°C is not less than 300 MPa.

[0015] As an improvement, the copper alloy is a copper-silver alloy, and the components of the copper-silver alloy are in a weight ratio of: silver 1% - 6%, and the balance is copper and inevitable impurities, and the total weight of the impurities is not more than 0.05%, and the oxygen content is lower than 9 ppm; the tensile strength of the highly conductive core wire after annealing is not less than 300 MPa, and the conductivity is greater than 80%; the conductivity of the composite wire filament under high-temperature working conditions is not less than 10%.

[0016] As an improvement, the core wire is made of copper; the conductivity of the composite wire single filament under the working condition of 600-1000 °C is not less than 15%.

[0017] Another object of the present invention is to provide a manufacturing method of a high-temperature corrosion-resistant stranded conductor in view of the deficiencies of the prior art. By manufacturing a core wire, manufacturing a high-temperature corrosion-resistant alloy tube, manufacturing a composite wire, and manufacturing a high-temperature corrosion-resistant stranded wire by means of stranding, the production of an ultra-fine-sized high-temperature-resistant stranded conductor is realized, meeting the requirements that the conductor maintains high strength, conductivity, and excellent oxidation and corrosion resistance under the high-temperature working condition of 600-1000 °C, so as to realize the normal use of the stranded conductor under high-temperature and corrosive working conditions, and solve the technical problem that the conductor in the prior art cannot work normally under high-temperature and corrosive working conditions.

[0018] To achieve the above object, the present invention provides the following technical solutions:

[0019] A manufacturing method of a high-temperature corrosion-resistant stranded conductor, comprising the following steps:

[0020] S1. Manufacture a core wire;

[0021] S2. Manufacture a high-temperature corrosion-resistant alloy tube:

[0022] 2.1. Tube making: Obtain a high-temperature corrosion-resistant alloy tube blank by vacuum casting and piercing, and perform necessary heat treatment;

[0023] 2.2. Ring rolling: Ring roll the tube blank to reduce its diameter and wall thickness and refine the grains to obtain a rolled tube;

[0024] 2.3. Drawing: Draw the corrosion-resistant alloy tube blank after ring rolling to further reduce its diameter to obtain a drawn tube;

[0025] 2.4. Polishing and cleaning: Polish and clean the inner wall of the drawn tube blank;

[0026] S3. Manufacture a composite wire:

[0027] 3.1. Tube threading: Insert the core wire obtained in step S1 into the high-temperature corrosion-resistant alloy tube obtained in step 2.4 to obtain an initial composite wire;

[0028] 3.2. Drawing: Perform a drawing treatment on the initial composite wire obtained in step 3.1 to make the core wire fit tightly with the high-temperature corrosion-resistant alloy tube;

[0029] 3.3. Bright annealing: Perform a bright annealing treatment on the product obtained in step 3.2;

[0030] 3.4. Repeat step 3.2 and step 3.3 in sequence until a composite wire single filament with the required outer diameter is obtained;

[0031] 3.5. Heat treatment: Heat treat the monofilaments of the composite wire under inert gas protection;

[0032] S4. Manufacture high-temperature corrosion-resistant stranded wire:

[0033] 4.1. Stranding: Strand several monofilaments of the composite wire obtained in step 3.5 to obtain a high-temperature corrosion-resistant stranded wire conductor;

[0034] 4.2. Heat treatment: Heat treat the high-temperature corrosion-resistant stranded wire conductor under inert gas protection.

[0035] As an improvement, in step S1, the steps of manufacturing the core wire with a copper-silver alloy are as follows:

[0036] 1.1. Continuous casting: Anaerobically melt the copper-silver alloy and continuously cast it to obtain a copper-silver alloy rod;

[0037] 1.2. Hot rolling: Hot roll the copper-silver alloy rod, rapidly cool it after reducing its diameter, and obtain a silver-copper rod blank with refined grains;

[0038] 1.3. Wire drawing: Draw the hot-rolled silver-copper alloy fine-grained rod blank through wire drawing to obtain an alloy rod with a certain diameter;

[0039] 1.4. Polishing and cleaning: Polish the copper-silver alloy rod and clean its surface.

[0040] As an improvement, in step S1, the steps of manufacturing the core wire with copper are as follows:

[0041] 1.1. Continuous casting: Anaerobically melt copper and continuously cast it to obtain a copper rod;

[0042] 1.2. Hot rolling: Hot roll the copper rod, rapidly cool it after reducing its diameter, and obtain a silver-copper rod blank with refined grains;

[0043] 1.3. Wire drawing: Draw the hot-rolled copper fine-grained rod blank through wire drawing to obtain a copper rod with a certain diameter;

[0044] 1.4. Polishing and cleaning: Polish the copper rod and clean its surface.

[0045] As an improvement, the total drawing deformation rate in step 3.2 does not exceed 40% each time.

[0046] As an improvement, the diameter size of the monofilaments obtained in step 3.4 is 0.08 - 0.5 mm, and more preferably 0.08 - 0.25 mm.

[0047] The beneficial effects of the present invention are as follows:

[0048] (1) By compounding a high-temperature corrosion-resistant alloy outside the highly conductive core material, the present invention enables the conductor to not only meet the normal signal transmission under high-temperature conditions but also work properly for a long time under high-temperature conditions, solving the technical problem that the conductor material in the prior art cannot work for a long time under high-temperature conditions.

[0049] (2) Through the conductor with a composite structure, the present invention enables the ultra-fine-sized conductor to maintain a high conductivity while also maintaining high strength and corrosion resistance to meet the normal signal transmission under high-temperature conditions.

[0050] (3) Through the ultra-fine-structured conductor material, the present invention saves the occupied space and weight during use, and is particularly suitable for working conditions with limited space requirements and weight requirements and long-term high-temperature working conditions.

[0051] In summary, the present invention has the advantages that it can work properly under the working conditions of 600 - 1000 °C, and is particularly suitable for working conditions with restrictions on the conductor wire diameter, installation space, and conductor weight and requiring the conductor to still have stable medium and low-frequency signal transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a schematic cross-sectional structure diagram of a single filament of the composite wire of the present invention;

[0053] Figure 2 It is a schematic diagram of the microscope view of the cross-section of a single filament of the composite wire of the present invention;

[0054] Figure 3 It is a schematic diagram of the microscope view of the surface of a single filament of the composite wire in Example 1 of the present invention after working for a long time under the working condition of 1000 °C;

[0055] Figure 4 It is a schematic diagram of the microscope view of the surface of a single filament of the composite wire in Example 2 of the present invention after working for a long time under the working condition of 1000 °C;

[0056] Figure 5 It is a schematic diagram of the microscope view of the surface of a single filament of the composite wire in Comparative Example 1 of the present invention after working for a long time under the working condition of 1000 °C;

[0057] Figure 6 It is a schematic diagram of the microscope view of the surface of a single filament of the composite wire in Comparative Example 3 of the present invention after working for a short time under the working condition of 1000 °C;

[0058] Figure 7 It is a schematic process flow diagram of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0059] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0060] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. are based on the orientation or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more unless otherwise specifically defined.

[0061] Embodiment 1

[0062] As Figures 1 - 3 shown, this embodiment provides a high-temperature corrosion-resistant stranded conductor, which is composed of a plurality of composite wire filaments stranded together. The composite wire filament is composed of a highly conductive core wire 1 and a high-temperature corrosion-resistant alloy 2 wrapped outside the core wire 1, so that the stranded conductor can maintain strength and transmit signals in a high-temperature atmospheric environment below 1000°C for a long time;

[0063] The highly conductive core wire 1 is copper or a copper alloy, and preferably a copper-silver alloy in this embodiment. The composition of the copper-silver alloy is by weight: silver 1% - 6%, and the balance is copper and inevitable impurities, and the total weight of the impurities is not more than 0.05%, and the oxygen content is lower than 9 ppm; the tensile strength of the highly conductive core wire 1 after annealing is not less than 300 MPa, and the conductivity is greater than 80%;

[0064] The composition of the high-temperature corrosion-resistant alloy 2 is by weight: nickel 60% - 75%, chromium 10.0% - 20.0%, molybdenum 5% - 15%, the total amount of tantalum and niobium 0.5% - 10%, tungsten 0.5% - 10%, aluminum 2.0% - 7.0%, titanium 0.1% - 1.0%, iron 0.1% - 2.0%, and the balance is inevitable trace impurities, and the total weight of the impurities is not more than 0.5%, and the oxygen content is lower than 9 ppm.

[0065] Furthermore, the cross-sectional area ratio of the core wire 1 in the composite wire single filament to the total area is 20% - 50%.

[0066] It should be noted that if the cross-sectional area ratio of the core wire 1 is too large, high conductivity can be achieved during the signal transmission of a thinner conductor, but the long-term working condition of high-temperature corrosion resistance cannot be achieved; if the cross-sectional area ratio of the core wire 1 is too small, the requirement for conductivity in signal transmission cannot be achieved, but the high-temperature corrosion resistance performance is excellent. Therefore, a suitable ratio selection needs to be made according to the actual working conditions. In some embodiments, the cross-sectional area ratio of the core wire 1 in the composite wire single filament to the total area is 30% - 50%.

[0067] In this embodiment, the tensile strength of the composite wire single filament at 20°C is greater than 400 MPa, the conductivity is greater than 20%, and the elongation is greater than 2%.

[0068] The conductivity of the composite wire single filament under high-temperature working conditions is not less than 10%.

[0069] The diameter of the composite wire single filament is 0.08 - 0.5 mm, preferably 0.08 - 0.25 mm, to realize the production of ultra-fine high-temperature resistant wires, which are particularly suitable for wire conductors used for signal transmission at ultra-high temperatures.

[0070] Among them, as Figure 7 shown, this embodiment also provides a method for manufacturing a high-temperature corrosion-resistant stranded conductor, including the following steps:

[0071] S1. Manufacture the core wire 1;

[0072] S2. Manufacture the high-temperature corrosion-resistant alloy tube 2:

[0073] 2.1. Tube manufacturing: Obtain a high-temperature corrosion-resistant alloy 2 tube blank through vacuum casting and piercing. The outer diameter of the tube is 40 - 80 mm, the wall thickness is 5 - 8 mm, and necessary heat treatment is carried out. The heat treatment temperature is 1100°C;

[0074] 2.2. Ring rolling: Ring roll the tube blank to reduce its diameter and wall thickness and refine the grains to obtain a rolled tube; By means of ring rolling, the grains of the alloy tube are refined, the strength and hardness of the alloy tube blank are improved, and the fatigue resistance, corrosion resistance and processing performance are improved; Preferably, the outer diameter of the tube after ring rolling is 20 mm, and the wall thickness is 2 - 3 mm;

[0075] 2.3. Drawing: Draw the corrosion-resistant alloy tube blank after ring rolling to further reduce its diameter to obtain a drawn tube; Preferably, the outer diameter of the tube after drawing is 8 mm, and the wall thickness is 1.5 - 2 mm;

[0076] 2.4. Polishing and cleaning: Polish and clean the inner wall of the drawn tube blank;

[0077] S3. Manufacture of composite wire:

[0078] 3.1 Pipe threading: Thread the copper-silver alloy core wire 1 obtained in step 1.4 into the high-temperature corrosion-resistant alloy 2 pipe obtained in step 2.4 to obtain an initial composite wire;

[0079] 3.2 Drawing: Perform drawing on the initial composite wire obtained in step 3.1 to make the core wire 1 fit tightly with the high-temperature corrosion-resistant alloy 2 pipe;

[0080] 3.3 Bright annealing: Perform bright annealing on the product obtained in step 3.2, and the annealing temperature is 800-900 °C;

[0081] 3.4 Repeat step 3.2 and step 3.3 in sequence until a composite wire single wire with the required outer diameter is obtained;

[0082] 3.5 Heat treatment: Perform heat treatment on the composite wire single wire under inert gas protection. The heat treatment method is annealing treatment, the temperature is 900 °C, and the holding time is 2 hours;

[0083] S4. Manufacture of high-temperature corrosion-resistant stranded wire:

[0084] 4.1 Stranding: Strand several composite wire single wires obtained in step 3.5 to obtain a high-temperature corrosion-resistant stranded wire conductor;

[0085] 4.2 Heat treatment: Perform heat treatment on the high-temperature corrosion-resistant stranded wire conductor under inert gas protection, and the heat treatment temperature is 400-500 °C.

[0086] Preferably, the total drawing deformation rate in each step of step 3.2 does not exceed 40%.

[0087] Preferably, in step S1, the steps of manufacturing the core wire 1 with copper-silver alloy are as follows:

[0088] 1.1 Continuous casting: Anaerobically melt the copper-silver alloy and continuously cast it to obtain a copper-silver alloy rod. Preferably, the size of the copper-silver alloy rod is 20 mm;

[0089] 1.2 Hot rolling: Hot roll the copper-silver alloy rod at a hot rolling temperature of 550-650 °C to reduce its diameter to 8 mm and rapidly cool it to room temperature to obtain a refined-grain silver-copper rod blank;

[0090] 1.3 Wire drawing: The hot-rolled copper-silver alloy fine-grain rod blank is wire-drawn to obtain an alloy rod with a certain diameter, where the diameter is wire-drawn from 8 mm to 4 mm;

[0091] 1.4 Polishing and cleaning: Polish and clean the surface of the copper-silver alloy rod.

[0092] Example 2

[0093] In this embodiment, the highly conductive core wire 1 is pure copper.

[0094] The conductivity of the composite wire single filament under high-temperature working conditions is not less than 15%.

[0095] Among them, in the manufacturing method steps, in step S1, the steps of manufacturing the core wire 1 with copper are as follows:

[0096] 1.1. Continuous casting: Oxygen-free melting of copper and continuous casting to obtain a copper rod with a diameter of 20 mm.

[0097] 1.2. Hot rolling: Hot rolling the copper rod, rapidly cooling it after reducing its diameter to obtain a silver copper rod blank with refined grains; preferably, the hot rolling temperature is 550-650 °C, reducing its diameter to 8 mm and rapidly cooling it to room temperature.

[0098] 1.3. Wire drawing: The hot-rolled copper fine-grained rod blank is drawn into a copper rod with a certain diameter through wire drawing; preferably, the diameter after wire drawing is 4 mm.

[0099] 1.4. Polishing and cleaning: Polishing the copper rod and cleaning its surface.

[0100] The rest is the same as in Embodiment 1.

[0101] Embodiment 3

[0102] In this embodiment, the components of the high-temperature corrosion-resistant alloy 2 are in a weight ratio of 60%-75% nickel, 10.0%-20.0% chromium, 6%-10% molybdenum, a total of 0.5%-10% tantalum and niobium, 0.5%-10% tungsten, 2.0%-7.0% aluminum, 0.1%-1.0% titanium, 0.1%-2.0% iron, the balance being inevitable trace impurities, the total weight of the impurities not exceeding 0.5%, and the oxygen content being less than 9 ppm.

[0103] The highly conductive core wire 1 is a copper-silver alloy, wherein the weight ratio of silver in the copper-silver alloy is 6%; the cross-sectional area of the core wire 1 accounts for 50% of the total area.

[0104] In this embodiment, the diameter of the composite wire single filament is 0.16 mm. The rest is the same as in Embodiment 1.

[0105] Embodiment 4

[0106] In this embodiment, the components of the high-temperature corrosion-resistant alloy 2 are in a weight ratio of 60%-75% nickel, 10.0%-20.0% chromium, 6%-10% molybdenum, 2%-3% tantalum, 1.5% niobium, 4%-5% tungsten, 2.0%-7.0% aluminum, 0.1%-1.0% titanium, 0.1%-2.0% iron, the balance being inevitable trace impurities, the total weight of the impurities not exceeding 0.5%, and the oxygen content being less than 9 ppm.

[0107] The highly conductive core wire 1 is a copper-silver alloy, wherein the weight ratio of silver in the copper-silver alloy is 6%; the cross-sectional area of the core wire 1 accounts for 40%-50% of the total area.

[0108] In this embodiment, the diameter of the single filament of the composite wire is 0.1 mm. The rest is the same as in Embodiment 1.

[0109] Comparative Example 1

[0110] In this embodiment, the components of the high-temperature corrosion-resistant alloy 2 are in a weight ratio of 60% - 75% nickel, 10.0% - 20.0% chromium, a total of 0.5% - 10% tantalum and niobium, 0.5% - 10% tungsten, 2.0% - 7.0% aluminum, 0.1% - 1.0% titanium, 0.1% - 2.0% iron, and the balance is inevitable trace impurities, the total weight of the impurities is not more than 0.5%, and the oxygen content is less than 9 ppm.

[0111] The highly conductive core wire 1 is a copper-silver alloy, wherein the weight ratio of silver in the copper-silver alloy is 6%; the cross-sectional area of the core wire 1 accounts for 50% of the total area.

[0112] In this embodiment, the diameter of the single filament of the composite wire is 0.16 mm. The rest is the same as in Embodiment 1.

[0113] Comparative Example 2

[0114] In this embodiment, the components of the high-temperature corrosion-resistant alloy 2 are in a weight ratio of 60% - 75% nickel, 10.0% - 20.0% chromium, 5% - 15% molybdenum, a total of 0.5% - 10% tantalum and niobium, 2.0% - 7.0% aluminum, 0.1% - 1.0% titanium, 0.1% - 2.0% iron, and the balance is inevitable trace impurities, the total weight of the impurities is not more than 0.5%, and the oxygen content is less than 9 ppm.

[0115] The highly conductive core wire 1 is a copper-silver alloy, wherein the weight ratio of silver in the copper-silver alloy is 6%; the cross-sectional area of the core wire 1 accounts for 50% of the total area.

[0116] In this embodiment, the diameter of the single filament of the composite wire is 0.16 mm. The rest is the same as in Embodiment 1.

[0117] Comparative Example 3

[0118] Adopt the technical solution of Embodiment 3 in the patent publication number CN118155913A to make a stranded conductor that maintains high strength and high conductivity in a high-temperature environment. After the stranded conductor in this comparative example works for a short time above 800 °C, its signal transmission performance is detected to fail, as Figure 6 shown, under the working condition of 1000 °C, the surface state after working for a short time. It can be seen from the attached drawing that the surface of the conductor has completely become charred, and the conductor is severely damaged and cannot be used normally.

[0119] The tensile properties and endurance properties of the stranded conductors of Examples 1 to 4 and Comparative Examples 1 to 3 were tested by conventional testing methods in the art, as shown in Table 1 and Table 2 below.

[0120] Table 1 Tensile property test.

[0121]

[0122] Table 2 Endurance life test.

[0123]

[0124] Since molybdenum can improve the high-temperature oxidation resistance of the alloy and tungsten can effectively inhibit the formation of voids during the creep process of the alloy under high-temperature conditions, as Figures 3 to 4 shown, combining Table 1 and Table 2 above, it can be seen that the surface quality of the composite wire single filaments in Examples 1 to 4 of the present invention after long-term operation under the condition of 1000 °C, and from the figure, it can also be seen that the surface morphology of the conductor remains intact, having excellent high-temperature corrosion resistance, and the conductor can work normally without signal interruption, and its strength and conductivity can meet the normal working requirements under the condition of 1000 °C.

[0125] From Figure 5 it can be seen that after the composite wire single filaments in Comparative Example 1 work for a long time under the condition of 1000 °C, the surface morphology of the conductor shows regular slight oxidation damage; under the same test conditions, the surface morphology of the composite wire single filaments in Comparative Example 2 is similar to Figure 5 that, and their endurance lives are much shorter than those of Examples 1 to 4.

[0126] In addition, from Figure 6 it can be seen that after the composite wire single filaments in Comparative Example 3 work for a short time under the condition of 1000 °C, parts of the conductor surface are incomplete and cannot work normally.

[0127] In addition, the comprehensive tensile strength of the composite wire single filaments in Examples 1 to 4 of the present invention is not less than 300 MPa under the high-temperature conditions of 600 - 750 °C.

[0128] In summary, the stranded conductors in the present invention, especially in the high-temperature environment of 800 - 1000 °C, have the advantages of saving space and weight, and can maintain high conductivity, corrosion resistance and relatively stable signal transmission performance.

[0129] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A high temperature corrosion resistant stranded conductor, characterized in that: The stranded conductor is composed of a plurality of composite wire monofilaments twisted together, wherein the composite wire monofilaments are composed of a highly conductive core wire (1) and a high-temperature corrosion-resistant alloy (2) wrapped around the core wire (1), so that the stranded conductor can maintain strength and transmit signals for a long time in a high-temperature atmospheric environment below 1000°C; The highly conductive core wire (1) is made of copper or a copper alloy; The composition of the high temperature corrosion resistant alloy (2) is 60% to 75% nickel, 10.0% to 20.0% chromium, 5% to 15% molybdenum, 0.5% to 10% of the total amount of tantalum and niobium, 0.5% to 10% of tungsten, 2.0% to 7.0% aluminum, 0.1% to 1.0% titanium, 0.1% to 2.0% iron, and the remainder is inevitable trace impurities, the total weight of which is not more than 0.5%, and the oxygen content is less than 9 ppm.

2. A high temperature corrosion resistant stranded conductor according to claim 1, characterized in that: The composition of the high temperature corrosion resistant alloy (2) is, by weight, 60% to 75% nickel, 10.0% to 20.0% chromium, 6% to 10% molybdenum, 2% to 3% tantalum, 1.5% niobium, 4% to 5% tungsten, 2.0% to 7.0% aluminum, 0.1% to 1.0% titanium, 0.1% to 2.0% iron, and the remainder is inevitable trace impurities, the total weight of which is no more than 0.5%, and the oxygen content is less than 9 ppm.

3. The high temperature corrosion resistant stranded conductor according to claim 1, characterized in that: The cross-sectional area of ​​the core wire (1) in the composite wire monofilament accounts for 20% to 50% of the total area.

4. The high temperature corrosion resistant stranded conductor according to claim 1, characterized in that: The diameter of the composite line monofilament is 0.08-0.5 mm.

5. The high temperature corrosion resistant stranded conductor according to claim 1, characterized in that: The tensile strength of the single filament of the composite wire at 20° C. is greater than 400 MPa, the conductivity is greater than 20%, and the elongation is greater than 2%.

6. The high temperature corrosion resistant stranded conductor according to claim 1, characterized in that: The comprehensive tensile strength of the monofilament of the composite line under high temperature conditions is as follows: the tensile strength at 1000°C is not less than 50MPa, the tensile strength at 900°C is not less than 80MPa, the tensile strength at 800°C is not less than 150MPa, and the tensile strength at 600-750°C is not less than 300MPa.

7. The high temperature corrosion resistant stranded conductor according to claim 1, characterized in that: The copper alloy is a copper-silver alloy, and the composition of the copper-silver alloy is as follows by weight: silver 1% to 6%, the remainder is copper and inevitable impurities, the total weight of the impurities is not more than 0.05%, and the oxygen content is less than 9 ppm; the highly conductive core wire (1) has a tensile strength of not less than 300 MPa after annealing, and a conductivity greater than 80%; the conductivity of the composite wire single wire under the working condition of 600-1000°C is not less than 10%.

8. The high temperature corrosion resistant stranded conductor according to claim 1, characterized in that: The core wire (1) is copper; the electrical conductivity of the composite wire single wire under the working condition of 600-1000°C is not less than 15%.

9. A method for manufacturing a high temperature corrosion resistant stranded conductor, characterized in that: The following steps are involved: S1, manufacturing core wire (1); S2. Manufacturing of high temperature corrosion resistant alloy (2) pipes: 2.

1. Tube making: The high temperature corrosion resistant alloy (2) tube blank is made by vacuum casting and perforation, and necessary heat treatment is performed; 2.2 Ring rolling: Ring rolling the tube billet to reduce its diameter and wall thickness, and refine the grains to obtain a rolled tube; 2.

3. Drawing: Drawing the corrosion-resistant alloy tube billet after ring rolling to further reduce its diameter to obtain a drawn tube; 2.

4. Polishing and cleaning: polish and clean the inner wall of the drawn tube blank; S3. Manufacturing composite line: 3.

1. Pipe threading: the core wire (1) obtained in step S1 is threaded into the high temperature corrosion resistant alloy (2) pipe obtained in step 2.4 to obtain an initial composite wire; 3.

2. Drawing: The initial composite wire obtained in step 3.1 is subjected to drawing treatment so that the core wire (1) and the high temperature corrosion resistant alloy (2) tube are closely attached; 3.3, bright annealing: bright annealing the product obtained in step 3.2; 3.4, repeating steps 3.2 and 3.3 in sequence until a composite wire monofilament with a desired outer diameter is obtained; 3.

5. Heat treatment: heat treatment of the composite wire monofilament under inert gas protection; S4. Manufacturing high temperature corrosion resistant stranded wire: 4.

1. Twisting: Twisting a plurality of composite wire monofilaments obtained in step 3.5 to obtain a high temperature corrosion resistant twisted wire conductor; 4.

2. Heat treatment: subject the high temperature corrosion resistant stranded conductor to inert gas protection heat treatment; The composition of the high temperature corrosion resistant alloy (2) is 60% to 75% nickel, 10.0% to 20.0% chromium, 5% to 15% molybdenum, 0.5% to 10% of the total amount of tantalum and niobium, 0.5% to 10% of tungsten, 2.0% to 7.0% aluminum, 0.1% to 1.0% titanium, 0.1% to 2.0% iron, and the remainder is inevitable trace impurities, the total weight of which is not more than 0.5%, and the oxygen content is less than 9 ppm.

10. The manufacturing method according to claim 9, characterized in that: In step 3.2, the total deformation rate of each drawing does not exceed 40%.

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