Tungsten alloy wire and its manufacturing method, and its use in cutting semiconductor materials

Abstract

This application relates to the technical field of tungsten alloy materials, and more particularly to tungsten alloy wires, methods for manufacturing the same, and their use in cutting semiconductor materials. The tungsten alloy consists of, as elements, L 0.4~1.1 wt%, Z 0.001~0.25 wt%, the remainder being tungsten and unavoidable impurities, where L is one or more of lanthanum, cerium, praseodymium, neodymium, gadolinium, and erbium, and Z contains oxygen and carbon, the wire diameter is 20~60 μm, and linear L or L compounds are present along the axial direction of the wire, with an average radial width D of L or L compounds being 5 nm or less. This invention improves the processing performance of tungsten alloy wires by doping linear L elements between tungsten matrices and controlling the average width of L in the radial direction to 5 nm or less, thereby enabling the wire to have a tensile strength of 5000 MPa or more with a wire diameter of 20 to 60 μm.

Description

[Technical Field]

[0001] This application relates to the technical field of tungsten alloy materials, and more particularly to tungsten alloy wires, methods for manufacturing the same, and their use in cutting semiconductor materials.

[0002] This application claims priority to a Chinese patent application filed with the China National Intellectual Property Office on December 26, 2023, with application number 2023118259397 and title of invention "Tungsten alloy wire, method for manufacturing the same, and use thereof," the entire contents of which are incorporated into this application by reference. [Background technology]

[0003] Tungsten alloys are alloy materials manufactured using powder metallurgy or injection molding techniques, with tungsten, a difficult-to-melt metal, as the hard phase and nickel, iron, copper, or silver as the adhesive phase. They possess excellent thermal, mechanical, electrical, and chemical properties, and are therefore widely used in fields such as automotive, medical, aerospace, military, and defense.

[0004] To further improve the overall mechanical properties of tungsten alloy wires, traditional methods involve doping and dispersing rare earth elements or compounds as a second phase into the tungsten matrix to strengthen the tungsten material. However, solid-liquid phase transitions are prone to occur during high-temperature sintering and recrystallization annealing processes, during which many second-phase particles coalesce and subsequently grow. Furthermore, in current pressure processing processes, uneven forging and wire drawing deformation cause fracture of the second-phase particles, resulting in an inability to effectively improve the strength of the tungsten matrix. Cracks are more likely to occur at the joints between the second-phase particles and the tungsten wire, which not only causes wire breakage but also limits the diameter size of the tungsten wire during deep processing.

[0005] For example, Patent Document 1 discloses an alloy wire having a lanthanum-containing oxide content of 0.1 wt% to 2.0 wt%, a method for manufacturing the same, and its use. The tensile strength of the alloy wire reaches 4800 MPa at a thickness of 40 μm or less. However, due to the large amount of rare earth oxide added, defects in the wire increase sharply, and the rate of wire breakage defects during the manufacturing process increases significantly. Furthermore, due to the aggregation of the rare earth second phase, the alloy wire becomes excessively resistant to deformation, leading to a decrease in the strength increase rate of the wire after thinning and a decrease in processing performance, thus failing to meet engineering requirements. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Chinese Patent Application Publication No. 113186438 Specification [Overview of the project]

[0007] To address the problem of the pre-existing technology where tungsten alloy wires exhibit many cracks and breaks due to the introduction of a second phase, this application provides a tungsten alloy wire, wherein the tungsten alloy consists of, by mass fraction, L 0.4~1.1 wt%, Z 0.001~0.25 wt%, the remainder being tungsten and unavoidable impurities. L is one or more of lanthanum, cerium, praseodymium, neodymium, gadolinium, and erbium, Z contains oxygen and carbon, the wire diameter is 20 to 60 μm, linear L or compounds of L exist along the axial direction of the wire, and the average radial width D of L or compounds of L is 5 nm or less.

[0008] For example, L represents lanthanum, or cerium, or praseodymium, or lanthanum and cerium, or lanthanum and neodymium, or lanthanum and praseodymium, or lanthanum and gadolinium, or cerium and praseodymium, or cerium and neodymium, or praseodymium and gadolinium, or praseodymium and erbium, or neodymium, or lanthanum, cerium and erbium, or lanthanum, praseodymium and neodymium, or cerium, praseodymium and neodymium, or praseodymium, neodymium, gadolinium and erbium, etc. Furthermore, for example, the mass percentage of L is 0.4%~1.1%, or 0.4%~1.0%, or 0.4%~0.8%, or 0.4%~0.6%, or 0.4%~0.5%, or 1.0%~1.1%, or 0.8%~1.1%, but of course, it may also be 0.4%, 0.41%, 0.5%, 0.55%, 0.6%, 0.8%, 0.86%, 1.0%, 1.05%, etc. The mass percentage of Z is 0.001% to 0.25%, or 0.001% to 0.05%, or 0.001% to 0.1%, or 0.001% to 0.2%, or 0.005% to 0.1%, or 0.1% to 0.25%, or 0.1% to 0.2%, or 0.05% to 0.2%, but of course, it may also be 0.0009%, 0.001%, 0.005%, 0.01%, 0.015%, 0.02%, 0.05%, 0.1%, 0.15%, 0.2%, etc.

[0009] The diameter of the wire is 20 to 60 μm, for example, 20 μm, 28 μm, 30 μm, 38 μm, 40 μm, 48 μm, 50 μm, 55 μm, 58 μm, 60 μm, etc., and the tungsten alloy wire may be uniform or not, and may have differences of a few percent, such as 1%, depending on the part.

[0010] Furthermore, "linear" means that in a wire, the size of L or L compound along the axial direction of the wire is much larger than the size along the radial direction of the wire.

[0011] Here, the compound L may be an oxide, such as lanthanum oxide, cerium oxide, praseodymium oxide, neodymium oxide, gadolinium oxide, or erbium oxide, but of course, it may also be a compound in other forms, such as a carbide of L.

[0012] In some embodiments, the average radial width of the tungsten crystal grains in the wire is 80 nm or less, and preferably, in the wire, if γ is the number of L or L compounds / number of tungsten crystal grains, then 3 ≤ γ ≤ 10.

[0013] Preferably, the number of surface defects in the wire is 10 or less per 100m.

[0014] Preferably, the dislocation density in the wire is 5 × 10 9 / mm 2 That's all.

[0015] To ensure the final strength of the resulting tungsten alloy wire, it is necessary to ensure that the wire possesses relatively good overall mechanical properties as well as good workability. For this reason, the ratio γ of the number of L or L compounds in the wire to the number of tungsten crystal grains is between 3 and 10. If γ is less than 3, the wire cannot meet the required breaking strength, and if γ exceeds 10, the workability of the wire deteriorates rapidly, resulting in a sharp increase in cracks and serious wire breakage.

[0016] Preferably, when the wire diameter is >50 μm and ≤60 μm, the average radial width D of L or the compound L is 5 nm or less, and the tensile strength of the wire is 5000 MPa or more; when the wire diameter is >40 μm and ≤50 μm, the average radial width D of L or the compound L is 4 nm or less, and the tensile strength of the wire is 5500 MPa or more. When the wire diameter of the wire material is > 30 μm and ≤ 40 μm, the average width D in the radial direction of L or the compound of L is 3 nm or less, and the tensile strength of the wire material is 6000 MPa or more. When the wire diameter of the wire material is ≥ 20 μm and ≤ 30 μm, the average width D in the radial direction of L or the compound of L is 2 nm or less, and the tensile strength of the wire material is 7000 MPa or more.

[0017] This application also provides a method for manufacturing the above tungsten alloy wire material, including wet doping, pulverization, pressing, sintering, block rolling, and pressure processing.

[0018] In some embodiments, the wet doping process: uniformly disperse tungsten blue oxide powder in deionized water to obtain a tungsten blue oxide suspension, uniformly disperse the nano-scale compound powder of L in an alkaline solution with pH > 11 to form a second suspension, and then spray the solution containing element Z and the second suspension into the tungsten blue oxide suspension in sequence, heat and dry to obtain doped tungsten blue oxide powder.

[0019] Preferably, after uniformly dispersing the nano-scale compound powder of L in an alkaline solution with pH > 11, stir it at high speed with a stirrer at 1000 - 2000 r / min. Preferably, the solution containing element Z is a salt solution of element Z or a suspension of a compound containing element Z. Preferably, the solution of element Z is diluted until the volume ratio is 1:20 or more. The preferred drying method is rapid vacuum heating drying.

[0020] By preparing a suspension of the compound of element L, fine particles can be directly and uniformly doped into the tungsten blue oxide powder, and these fine particles can be co-crystallized and precipitated with tungsten crystal grains as heterogeneous crystal nuclei, thereby enabling the more uniform dispersion distribution of the tungsten alloy powder that can be manufactured. In this method, it is no longer necessary to use the acid salt form of the element, thereby expanding the selection range of the dispersible particles that can be manufactured, and making the performance of the obtained tungsten material more stable and reliable.

[0021] In some embodiments, the method for manufacturing the blue tungsten oxide powder is as follows. Ammonium paratungstate is fed into a reduction furnace and reduced at 400 - 600 °C under the protection of hydrogen gas and nitrogen gas to obtain blue tungsten oxide powder. Here, the thickness of the ammonium paratungstate powder material layer is less than 10 mm. In the reduction furnace, the flow rate of hydrogen gas is 20 - 40 L / min, the flow rate of nitrogen gas is 80 - 160 L / min, the oxygen index of the blue tungsten oxide powder is 2.85 ± 0.05, and the ammonium tungsten bronze phase component is more than 80%.

[0022] The blue tungsten oxide powder is manufactured using a mixed gas of hydrogen and nitrogen as a reduction protection medium. The performance of the discharged blue tungsten oxide powder is controlled by the thickness of the material layer, the amount and flow direction of hydrogen gas. Doping is carried out so that the oxygen index of the blue tungsten oxide is 2.85 ± 0.05 and the proportion of the ammonium tungsten bronze phase exceeds 80%. The blue tungsten oxide has coarse particles and many cracks on the surface, which is advantageous for the infiltration of the rare earth solution and the improvement of the doping effect. Thereby, the uniformity of the second-phase distribution in the tungsten wire is improved, and the comprehensive mechanical properties and processing performance of the tungsten wire are improved.

[0023] In some embodiments, the powdering process is as follows. The doped blue tungsten oxide powder is reduced to obtain tungsten alloy powder A with a particle size of 1.5 - 2.6 μm and tungsten alloy powder B with a particle size of 3.8 - 4.5 μm respectively. Next, alloy powder A and alloy powder B are uniformly mixed to obtain a mixed powder.

[0024] Preferably, as the reduction method of the alloy powder A, the doped blue tungsten oxide powder is first reduced at 500 - 800 °C in a hydrogen reduction furnace, and then secondary reduction is carried out at 700 - 1000 °C in the hydrogen reduction furnace to obtain tungsten alloy powder A with a particle size of 1.5 - 2.6 μm.

[0025] Preferably, as a method for reducing the alloy powder B, the doping blue tungsten oxide powder is reduced in a hydrogen reduction furnace at 700 to 1100°C to obtain tung alloy powder B with a particle size of 3.8 to 4.5 μm.

[0026] Preferably, the alloy powder A and alloy powder B are uniformly mixed in a mass ratio of 1:(1-2).

[0027] By mixing fine tungsten alloy powder produced by two reduction processes with coarse tungsten alloy powder produced by one high-temperature reduction process in a fixed ratio, it is possible to not only avoid localized doping non-uniformity of the coarse powder during reduction, but also effectively suppress aggregation and concentration of the fine powder after reduction. This reduces the risk of defects and wire breakage in subsequent pressurizing processes due to microscopic non-uniformity of the alloy powder doping.

[0028] In some embodiments, the sintering process is as follows: The pre-sintered material strip obtained by the press is sintered by applying an electric current, and the sintering is carried out in two stages. In the first sintering stage, the material is sintered for 30 to 45 minutes at a current intensity of 60% of the tungsten rod's melting current, and then cooled. In the second sintering stage, the material is sintered for 40 to 80 minutes at a current intensity of 90% to 92% of the tungsten rod's melting current, resulting in a density of 18.6 g / cm³. 3 The above sintered elementary strips are obtained.

[0029] Preferably, the second sintering is carried out in a hydrogen atmosphere, where the purity of the hydrogen gas is over 99.5%.

[0030] Unlike conventional sintering modes involving a single pass of current at high temperature, or sintering modes combining current sintering and medium-frequency indirect sintering, this method employs a two-stage current-high-temperature sintering process. The density of the strips obtained by conventional methods, such as sintering with a single current pass or sintering using a combination of vertical melting and medium frequency, is 17.2-18.4 g / cm³. 3The density only reaches a certain level, which is approximately 92% or less of the theoretical density. Furthermore, the uniformity of the structure differs greatly between the ends and the center, meaning that the uniformity of the tungsten wire fiber size is poor. As a result, the structure becomes uneven in subsequent processing steps of the tungsten alloy material, making the wire prone to breakage. This invention improves the consistency of the structure of the tungsten strip by thoroughly volatilizing impurity elements in the tungsten strip during the first energized sintering, closing the gaps on the surface of the tungsten strip, and by improving the purity of the hydrogen gas during the second energized high-temperature sintering, thereby improving the density of the strip and obtaining a uniform strip with a density of 96% or more. This improves the consistency of the strip structure, improves the consistency of the fibers of the subsequent tungsten alloy wire, and improves the winding performance of the tungsten alloy wire.

[0031] In some embodiments, the pressure processing step is as follows: The alloy rod obtained by the bract rolling is recrystallized and annealed, then forged using a multi-pass continuous rotary forging apparatus to obtain a tungsten rod with a diameter of 2.5 to 4.0 mm, and the tungsten rod is subjected to thick wire drawing using wire drawing dies of different specifications, with the wire drawing pass repeated multiple times to achieve a compression ratio of 35% to 60%, thereby obtaining a thick tungsten alloy wire rod with a diameter of 0.3 to 0.5 mm.

[0032] By processing tungsten alloy wire at a high compression ratio of 35% to 60%, the fibers of the resulting wire develop more, which is advantageous for the linearization of L elements and their compounds during processing, thereby improving the breaking strength of the wire.

[0033] In some embodiments, during the pressure processing, the alloy rod obtained by the bract rolling is heated to 2000-2600°C using a medium-to-high frequency induction coil to recrystallize and anneal.

[0034] In some embodiments, the tungsten alloy wire needs to be annealed when drawn to a diameter of 0.3 to 0.5 mm, with an annealing temperature of 1300 to 1800°C. After annealing, the tungsten alloy wire is cooled in an oxygen atmosphere and repeatedly drawn to obtain tungsten alloy wires of different diameter specifications. When the tungsten alloy wire is drawn to a diameter of 0.3 mm or less, the annealing process is discontinued. The annealed and cooled wires are drawn using drawing dies of different specifications, and the drawing process is repeated until the desired wire diameter is reached.

[0035] By annealing the wire and then subjecting it to oxygen cooling, the content and thickness of the oxide layer on the surface of the tungsten alloy wire can be increased, effectively improving the lubrication layer of the wire. This improves the wire drawing conditions, ensuring the feasibility of drawing the wire at a high compression ratio, and thereby significantly reducing the probability of wire breakage.

[0036] This application also provides the use of the above-mentioned tungsten alloy wire in the fields of cutting, cut protection, cables, screen printing, ropes, or spinning.

[0037] This application also provides the use of the above-mentioned tungsten alloy wire in cutting semiconductor materials. [Effects of the Invention]

[0038] Compared to conventional technology, the tungsten alloy wire according to this application has the following advantages.

[0039] This invention strengthens a tungsten material with one or more rare earth elements / compounds as the second phase, controls the L element to linearly dope between the tungsten matrices, and sets the average radial width of L to less than 5 nm. This significantly reduces cracks and breaks caused by the second phase particles during subsequent pressurizing processes, which is advantageous for ensuring the mechanical strength of the tungsten alloy wire. The wire has a tensile strength of 5000 MPa or more, especially at a diameter of 60 μm, and the processing performance of the tungsten alloy wire is also improved. [Brief explanation of the drawing]

[0040] [Figure 1] This is a schematic diagram showing the measurement of the average radial width of L or L compound relating to the present application. [Modes for carrying out the invention]

[0041] To more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that may be used in describing the embodiments or the prior art will be briefly described below. The drawings in the following description are some embodiments of the present invention, and it will be apparent to those skilled in the art that other drawings can be obtained based on these drawings without any creative effort.

[0042] To clarify the purpose, technical solutions, and advantages of the embodiments of this application, the technical solutions in the embodiments of this application will be described clearly and completely below. Clearly, the embodiments described are a part of the embodiments of this application, but not all of them. All other embodiments that a person skilled in the art could obtain without creative effort based on the embodiments of this application are within the scope of protection of this application.

[0043] This application provides a tungsten alloy wire, wherein the tungsten alloy is, as an element, by mass fraction, L 0.4~1.1 wt%, Z 0.001~0.25 wt%, consisting of the remainder being tungsten and unavoidable impurities. The aforementioned L is one or more of the following: lanthanum, cerium, praseodymium, neodymium, gadolinium, and erbium. The aforementioned Z includes oxygen and carbon. The wire has a diameter of 20 to 60 μm, and a linear L or L compound exists along the axial direction of the wire, with an average radial width D of the L or L compound being 5 nm or less.

[0044] Inevitable impurities are understood to be other elements introduced during the manufacturing process.

[0045] The average radial width of tungsten crystal grains is 80 nm or less. In the aforementioned wire, if γ is the number of L or L compounds divided by the number of tungsten crystal grains, then 3 ≤ γ ≤ 10.

[0046] When the wire diameter of the aforementioned wire is >50 μm and ≤60 μm, the average radial width D of L or the compound of L is 5 nm or less, and the tensile strength of the wire is 5000 MPa or more. When the wire diameter of the aforementioned wire is >40 μm and ≤50 μm, the average radial width D of L or the compound of L is 4 nm or less, and the tensile strength of the wire is 5500 MPa or more. When the wire diameter of the aforementioned wire is >30 μm and ≤40 μm, the average radial width D of L or the compound of L is 3 nm or less, and the tensile strength of the wire is 6000 MPa or more. When the wire diameter of the aforementioned wire is ≥20 μm and ≤30 μm, the average radial width D of L or the compound of L is 2 nm or less, and the tensile strength of the wire is 7000 MPa or more. The number of surface defects in the aforementioned wire is 10 or less per 100m. In the aforementioned wire, the dislocation density is 5 × 10 9 / mm 2 That's all.

[0047] This application provides a method for manufacturing tungsten alloy wire, including wet doping, powdering, pressing, sintering, bloc rolling, and pressure processing. The wet doping step: Blue tungsten oxide powder is uniformly dispersed in deionized water to obtain a blue tungsten oxide suspension, L nanoscale compound powder is uniformly dispersed in an alkaline solution with pH > 11 to form a second suspension, then the solution containing element Z and the second suspension are sequentially sprayed onto the blue tungsten oxide suspension, and after spraying is complete, rapid vacuum heating and drying is performed to obtain doped blue tungsten oxide powder. Method for producing the blue tungsten oxide powder: Ammonium paratungstate is sent to a reduction furnace and reduced at 400-600°C under the protection of hydrogen and nitrogen gases to obtain blue tungsten oxide powder. Here, the thickness of the ammonium paratungstate powder material layer is less than 10 mm, the flow rate of hydrogen gas in the reduction furnace is 20-40 L / min, the flow rate of nitrogen gas is 80-160 L / min, the oxygen index of the blue tungsten oxide powder is 2.85 ± 0.05, and the ammonium tungsten bronze phase component is more than 80%. The aforementioned powdering: The doped blue tungsten oxide powder is subjected to primary reduction in a hydrogen reduction furnace at 500-800°C, and then to secondary reduction in a hydrogen reduction furnace at 700-1000°C to obtain tung alloy powder A with a particle size of 1.5-2.6 μm. The doped blue tungsten oxide powder is reduced in a hydrogen reduction furnace at 700-1100°C to obtain tung alloy powder B with a particle size of 3.8-4.5 μm. A mixed powder is obtained by uniformly mixing alloy powder A and alloy powder B in a mass ratio of 1:(1-2). The aforementioned sintering: The pre-sintered tungsten rod obtained by the press is sintered by applying an electric current, and the sintering is carried out in two stages. In the first sintering, it is sintered for 30 to 45 minutes at a current intensity of 60% of the tungsten rod's melting current, and then cooled. In the second sintering, it is sintered for 40 to 80 minutes at a current intensity of 90% to 92% of the tungsten rod's melting current, resulting in a density of 18.6 g / cm³. 3 The above sintered elementary strips were obtained, Preferably, the second sintering is carried out in a hydrogen atmosphere, where the purity of the hydrogen gas is over 99.5%. The aforementioned pressure processing: The alloy rod obtained by the aforementioned bract rolling is heated to 2000-2600°C in a medium-high frequency induction coil to recrystallize and anneal, and then forged using a multi-pass continuous rotary forging apparatus to form a tungsten rod with a diameter of 2.5-4.0 mm. The aforementioned tungsten rod is subjected to thick wire drawing using wire drawing dies of different specifications, and the wire drawing pass is repeated multiple times to achieve a compression ratio of 35% to 60%, thereby obtaining thick tungsten alloy wire with a diameter of 0.3 to 0.5 mm. The tungsten alloy wire must be drawn to a diameter of 0.3 to 0.5 mm and then annealed at a temperature of 1300 to 1800°C. After annealing, the tungsten alloy wire is cooled in an oxygen atmosphere. After annealing and cooling, the wire is drawn using drawing dies of different specifications, and the drawing process is repeated until the desired wire diameter is reached.

[0048] Furthermore, the pressing and bract rolling steps in the above steps preferably employ the following embodiments, but are not limited thereto. That is, Pressing: Using a hydrostatic method, the mixed powder is pressed at a pressure of 140-240 MPa to form compacts weighing 1.5-6 kg each. These compacts are then pre-sintered at a low temperature of 1200-1400°C for 10-30 minutes in a hydrogen atmosphere to increase their strength.

[0049] Ball rolling: Using a cluster rolling mill, sintered strips with a diameter of 15-25 mm are continuously rolled at 1600-1700°C to ball-roll them into alloy rods with a diameter of 8.0-12.0 mm.

[0050] The manufacturing method further includes a post-treatment step of electrolytic cleaning to facilitate subsequent electroplating work.

[0051] Therefore, this application provides the tungsten alloy elemental compositions of the examples and comparative examples shown in Table 1 below.

[0052] [Table 1] (Unit: wt%) Here, "-" indicates the absence of the element in question.

[0053] Example 1.1 This embodiment is a tungsten alloy wire manufactured in accordance with the present invention, the elemental composition of which includes 0.4 wt% lanthanum, 0.4 wt% cerium, 0.01 wt% carbon, 0.16 wt% oxygen, the remainder being tungsten and unavoidable impurities.

[0054] The manufacturing steps are as follows: Step 1. Production of blue tungsten oxide: Ammonium paratungstate powder was subjected to hydrogen gas reduction in a countercurrent hydrogen continuous reduction furnace at 400°C, 450°C, 500°C, and 560°C. With a material layer thickness of 8 mm, a hydrogen gas flow rate of 30 L / min, and a nitrogen gas flow rate of 140 L / min, blue tungsten oxide powder with an oxygen index of 2.87 and an ammonium tungsten bronze phase component of 82% was obtained.

[0055] Step 2. Wet doping: The blue tungsten oxide powder obtained in Step 1 was uniformly dispersed in deionized water to obtain a blue tungsten oxide suspension, where the volume ratio of blue tungsten oxide powder to deionized water was 1:15. An appropriate amount of carbon powder and deionized water were uniformly mixed in a mass ratio of 1:20 to obtain a first suspension. An appropriate amount of nanoscale powder of lanthanum oxide and cerium oxide was uniformly dispersed in a pH 13 sodium hydroxide solution and stirred at a high speed of 1500 r / min in a high-speed emulsifier to form a second suspension. Next, the first and second suspensions were sprayed onto the blue tungsten oxide suspension via a vacuum tube. After spraying was complete, rapid vacuum heating and drying was performed to obtain doped blue tungsten oxide powder. All remaining steps were the same as in Example 1.1.

[0056] Step 3. Powdering: The doped blue tungsten oxide powder obtained in Step 2 was subjected to primary reduction in a 3-temperature hydrogen reduction furnace at 500°C, 650°C, and 750°C, and then to secondary reduction in a 4-temperature hydrogen reduction furnace at 700°C, 810°C, 870°C, and 920°C to obtain tung alloy powder A with a particle size of 2.0 μm. The doped blue tungsten oxide powder obtained in Step 2 was reduced in a four-temperature hydrogen reduction furnace at 720°C, 820°C, 870°C, and 950°C to obtain tung alloy powder B with a particle size of 4.1 μm. Alloy powder A and alloy powder B were placed in a 1:1.5 ratio into a high-energy powder mixer and mixed for 120 minutes until uniformly mixed, resulting in a mixed powder with a particle size of 3.0 μm.

[0057] Step 4. Pressing: Using a hydrostatic method, the mixed powder obtained in Step 3 was pressed at a pressure of 160 MPa to form a compact weighing 3 kg. The compact was then pre-sintered in a hydrogen atmosphere at 1300°C for 20 minutes to obtain a pre-sintered particle strip.

[0058] Step 5. Sintering: The pre-sintered tungsten rod obtained in Step 4 is sintered by applying current, and the sintering is carried out in two stages. In the first sintering, it is sintered for 40 minutes at a current intensity of 60% of the tungsten rod's cutting current, then cooled, the vertical cutting cover is purged and dried. In the second sintering, it is sintered for 60 minutes at a current intensity of 91% of the tungsten rod's cutting current, resulting in a density of 18.68 g / cm³. 3 A sintered element strip was obtained.

[0059] Step 6. Ball Rolling: Using a cluster rolling mill, the sintered strips with a diameter of 20 mm were continuously rolled at a heating temperature of 1600°C to form 8.0 mm alloy rods.

[0060] Step 7. Pressurization: The alloy rod obtained in Step 6 was heated to 2400°C using a high-frequency induction coil to recrystallize and anneal it, and then forged using a multi-pass continuous rotary forging machine to form a tungsten rod with a diameter of 3.0 mm.

[0061] Step 8. The tungsten rod was drawn using drawing dies of different sizes, and the drawing pass was repeated multiple times to achieve a compression ratio of 35% to 60%, resulting in thick tungsten alloy wire with a diameter of 0.5 mm.

[0062] Step 9. Annealing: The tungsten alloy wire obtained in Step 8 was processed to a diameter of φ0.5 mm and then annealed. After annealing, the tungsten alloy wire was cooled in an oxygen atmosphere. At a diameter of φ0.5 mm, the annealing temperature was 1600°C.

[0063] Step 10. The annealed wire obtained in Step 9 was drawn using drawing dies of different specifications, and the drawing process was repeated multiple times to draw wires to diameters of 58 μm, 48 μm, 38 μm, 28 μm, and 20 μm, respectively.

[0064] Step 11. Electrolytic cleaning: First, the tungsten alloy wire obtained in Step 10 was electrolytically treated with a 22 wt% potassium hydroxide solution containing 12 sets of AC electrolytic sheets. Next, it was sequentially electrolytically treated with six groups of 6 wt% potassium hydroxide solutions containing 5 sets of DC electrolytic sheets at an electrolytic rate of 180 m / min. After electrolysis, the surface was washed with deionized water to obtain white tungsten fine wires of different diameters.

[0065] Example 1.2 The difference between this embodiment and Example 1.1 is that the elemental composition of the material includes 0.2 wt% lanthanum, 0.2 wt% cerium, 0.01 wt% carbon, 0.08 wt% oxygen, the remainder being tungsten and unavoidable impurities. The remaining manufacturing steps were the same as in Example 1.1.

[0066] Example 1.3 The difference between this embodiment and Example 1.1 is that the elemental composition of the material includes 0.55 wt% lanthanum, 0.55 wt% cerium, 0.03 wt% carbon, 0.22 wt% oxygen, the remainder being tungsten and unavoidable impurities. The remaining manufacturing steps were the same as in Example 1.1.

[0067] Comparative Example 1.1 The elemental components of the material include 0.8 wt% of lanthanum, 0.138 wt% of oxygen, and the balance of tungsten and inevitable impurities.

[0068] The manufacturing steps are as follows. Step 1. Doping: An appropriate amount of lanthanum nitrate solution was uniformly doped into blue tungsten oxide powder. After thorough stirring, it was dried at a low temperature of 80 °C for 4 hours and then dried according to the mode of drying at a high temperature of 120 °C.

[0069] Step 2. Reduction: For the material obtained in Step 1, the doped powder was primary-reduced in a four-temperature-zone reduction furnace to form alloy powder with appropriate particle size.

[0070] Step 3. Powder mixing: The material obtained in Step 2 was put into a powder mixer according to the particle size. The powder was mixed for 80 minutes at a rotation speed of 8 revolutions per minute.

[0071] Step 4. Powder pressing: By the hydrostatic pressure method, the powder with different particle sizes was pressed at a pressure of 200 MPa to form a green compact with a single weight of 3.0 kg. The green compact was preliminarily sintered at a low temperature under a hydrogen atmosphere to enhance the strength of the green compact.

[0072] Step 5. High-temperature sintering: High-temperature sintering was carried out to obtain a sintered bar with a density of 18.10 g / cm 3 ³.

[0073] Step 6. Block rolling: Using a cluster rolling mill, continuous rolling was carried out at a heating temperature of 1650 °C to block-roll a sintered bar with a diameter of 23.0 mm into an alloy rod with a diameter of 8.0 mm.

[0074] Step 7. Pressing process: Multi-pass rotary forging was used. Then, wire drawing was carried out with wire drawing dies of different specifications, and wire drawing was repeated multiple times to form alloy wire with diameters of 58 μm, 48 μm, 38 μm, 28 μm, and 20 μm respectively.

[0075] Comparative Example 1.2 The elemental composition of the material includes 0.8 wt% cerium, 0.183 wt% oxygen, the remainder being tungsten and unavoidable impurities.

[0076] The manufacturing steps are as follows: Step 1. Doping: A suitable amount of lanthanum nitrate solution was uniformly doped onto the blue tungsten oxide powder, and after thorough stirring, the powder was dried according to a mode that involved drying at a low temperature of 80°C for 4 hours, followed by drying at a high temperature of 120°C.

[0077] Step 2. Reduction: The material obtained in Step 1 was subjected to primary reduction of the doped powder in a four-temperature reduction furnace to obtain an alloy powder with an appropriate particle size.

[0078] Step 3. Powder Mixing: The materials obtained in Step 2 were placed in a powder mixer according to their particle size. The powder was mixed at a rotation speed of 8 revolutions per minute for 80 minutes.

[0079] Step 4. Powder Pressing: Using a hydrostatic method, powders with different particle sizes were pressed at a pressure of 200 MPa to form compacts weighing 3.0 kg each. The compacts were then pre-sintered at a low temperature under a hydrogen atmosphere to increase their strength.

[0080] Step 5. High-temperature sintering: High-temperature sintering is performed to achieve a density of 18.10 g / cm³. 3 A sintered element strip was obtained.

[0081] Step 6. Ball Rolling: Using a cluster rolling mill, the sintered strips with a diameter of 23.0 mm were ball-rolled into 8.0 mm alloy rods by continuous rolling at a heating temperature of 1650°C.

[0082] Step 7. Pressure processing: Multi-pass rotary forging was used. Subsequently, the wire was drawn using wire drawing dies of different specifications, and the drawing process was repeated multiple times to produce alloy wires with diameters of 58 μm, 48 μm, 38 μm, 28 μm, and 20 μm, respectively.

[0083] Comparative Example 1.3 (Z element content exceeds 0.25 wt%) The difference from Example 1.1 is that the elemental composition of the material includes 0.4 wt% cerium, 0.4 wt% lanthanum, 0.1 wt% carbon, 0.16 wt% oxygen, the remainder being tungsten and unavoidable impurities. The remaining manufacturing steps were the same as in Example 1.1.

[0084] Comparative Example 1.4 (Total content of the second phase of element L is over 1.1 wt%) The difference from Example 1.1 is that the elemental composition of the material includes 0.6 wt% cerium, 0.6 wt% lanthanum, 0.01 wt% carbon, 0.24 wt% oxygen, the remainder being tungsten and unavoidable impurities. The remaining manufacturing steps were the same as in Example 1.1.

[0085] Comparative Example 2.1 (Deionized water used as the solvent for element L) The elemental composition of the material is the same as in Example 1.1. The differences between Comparative Example 2.1 and Example 1.1 are as follows: The blue tungsten oxide powder obtained in Step 1 was uniformly dispersed in deionized water to obtain a blue tungsten oxide suspension, where the volume ratio of blue tungsten oxide powder to deionized water was 1:15. An appropriate amount of carbon powder and deionized water were uniformly mixed in a mass ratio of 1:20 to obtain a first suspension. An appropriate amount of lanthanum nitrate and cerium nitrate crystalline powder were uniformly dispersed in deionized water and stirred at a high speed of 1500 r / min in a high-speed emulsifier to form a second suspension. Next, the first and second suspensions were added to the blue tungsten oxide suspension, stirred thoroughly, and dried to obtain doped blue tungsten oxide. The stirring speed was 40 r / min and the drying temperature was 160°C. The remaining steps were all the same as in Example 1.1. The remaining steps were the same as in Example 1.1.

[0086] Comparative Example 2.2 (Alloy powder was manufactured by primary reduction) The elemental composition of the material is the same as in Example 1.1. The differences between Comparative Example 2.2 and Example 1.1 are as follows: Step 3, Powdering: The doped blue tungsten oxide powder obtained in Step 2 was reduced in a four-temperature hydrogen reduction furnace at 650°C, 750°C, 850°C, and 930°C at a reduction rate of 20 minutes / boat to obtain tung alloy powder with a particle size of 3.0 μm. The remaining steps were the same as in Example 1.1.

[0087] Comparative Example 2.3 (Using a compression ratio of 10% to 30% for a typical wire drawing path) The elemental composition of the material is the same as in Example 1.1. The differences between Comparative Example 2.3 and Example 1.1 are as follows: Step 8. The tungsten rod was drawn using drawing dies of different sizes, and the drawing pass was repeated multiple times to achieve a compression ratio of 10% to 30%, thereby obtaining thick tungsten alloy wire with a diameter of 0.5 mm. The remaining steps were the same as in Example 1.1.

[0088] Comparative Example 2.4.1 (Cooling in an air atmosphere after annealing) The elemental composition of the material is the same as in Example 1.1. The differences between Comparative Example 2.4.1 and Example 1.1 are as follows: Step 9. Annealing: The tungsten alloy wire obtained in Step 8 was processed to a diameter of φ0.5 mm and then annealed. After annealing, the tungsten alloy wire was cooled in an air atmosphere. At a diameter of φ0.5 mm, the annealing temperature was 1600°C. The remaining steps were the same as in Example 1.1.

[0089] Comparative Example 2.4.2 (Cooling in an air atmosphere after annealing) The elemental composition of the material is the same as in Example 1.1. The differences between Comparative Example 2.4.2 and Example 1.1 are as follows: Step 9. Annealing: The tungsten alloy wire obtained in Step 8 was processed to a diameter of φ0.5 mm and then annealed. After annealing, the tungsten alloy wire was cooled in an air atmosphere. At a diameter of φ0.5 mm, the annealing temperature was 1650°C. The remaining steps were the same as in Example 1.1.

[0090] Comparative Example 2.4.3 (Cooling in an air atmosphere after annealing) The elemental composition of the material is the same as in Example 1.1. The differences between Comparative Example 2.4.3 and Example 1.1 are as follows: Step 9. Annealing: The tungsten alloy wire obtained in Step 8 was processed to a diameter of φ0.5 mm and then annealed. After annealing, the tungsten alloy wire was cooled in an air atmosphere. At a diameter of φ0.5 mm, the annealing temperature was 1700°C. The remaining steps were the same as in Example 1.1.

[0091] Comparative Example 2.4.4 (Cooled in an air atmosphere after annealing) The elemental composition of the material is the same as in Example 1.1. The differences between Comparative Example 2.4.4 and Example 1.1 are as follows: Step 9. Annealing: The tungsten alloy wire obtained in Step 8 was processed to a diameter of φ0.5 mm and then annealed. After annealing, the tungsten alloy wire was cooled in an air atmosphere. At a diameter of φ0.5 mm, the annealing temperature was 1550°C. The remaining steps were the same as in Example 1.1.

[0092] Microstructure and performance testing Tensile strength tests were conducted on the tungsten alloy wires obtained in the examples and comparative examples, and their properties were evaluated using a transmission electron microscope. The gamma values ​​were calculated, and the test results are shown in Tables 2 and 3.

[0093] The tungsten alloy wires obtained in the examples and comparative examples were cut into sheets along the axial direction of the tungsten alloy wire using a focused ion beam cutting apparatus. These sheets were placed in a high-resolution transmission electron microscope and characterized in different modes. The number of linear second phases, the number of tungsten crystal grains, and the grain boundary angles of the tungsten crystal grains were observed within the sample sheet, and the γ value and the percentage of tungsten crystal grains with grain boundary angles of 15° or less were calculated. Formula for calculating the gamma value: γ = Number of linear second phases / Number of tungsten crystal grains The proportion of grain boundary angles of tungsten grains less than or equal to 15° = Number of grain boundary angles of tungsten grains less than or equal to 15° / (Number of grain boundary angles of tungsten grains less than or equal to 15° + Number of grain boundary angles greater than 15°) × 100%

[0094] In this tensile strength test, a 200 mm long tungsten wire was clamped using a standard tensile testing machine, and a load was applied to one end at a constant speed to obtain fracture force data.

[0095] Tensile strength is calculated using the following formula: σ = F / S Here, F is the breaking force (N) and S is the area of ​​the original cross-section (mm).

[0096] [Table 2] JPEG2026517725000004.jpg103170 Here, " / " indicates that there is no corresponding data.

[0097] The number of surface defects, the average diameter of tungsten grains, the average radial width of L or L compound, and the dislocation density of the tungsten alloy wires obtained in the examples and comparative examples were measured, and the measurement results are shown in Table 3.

[0098] The method for measuring the number of surface defects is as follows: Surface defects are detected in the obtained tungsten alloy wire using an eddy current flaw detection device, and defects are defined as those in which the depth of the detection signal exceeds 15% of the diameter. The method for measuring the average radial width of tungsten crystal grains is as follows: A sheet is cut along the axial direction of the wire using a focused ion beam cutting device, and this sheet is set in a scanning electron microscope equipped with a backscatter diffractometer (EBSD) to collect the morphology of the tungsten crystal grains of the sample under test. The width of the upper and lower grain boundaries is measured using conventional measurement software to obtain the average radial width of the tungsten crystal grains, and the average value of the measured widths of multiple tungsten crystal grains is calculated and taken as the average radial width of the tungsten crystal grains.

[0099] The method for measuring the average radial width of L or L compounds is as follows: As shown in Figure 1, a sheet is cut along the axial direction of the tungsten alloy wire 1 using a focused ion beam cutting device. This sheet is set in a high-resolution transmission electron microscope, and first, the morphology is observed in bright-field and dark-field modes. A surface scan is performed at a position with significant morphological contrast, and a line scan is performed at a position perpendicular to the axial direction of the tungsten alloy wire to obtain information on elemental distribution and elemental composition. Among the detected samples, positions with significant morphological contrast and significantly different elemental distributions (i.e., positions of aggregation regions of each element in the second phase) are photographed with a transmission electron microscope to obtain high-resolution images of the second phase, and these high-resolution images are Fourier transformed to obtain lattice diffraction spectra. Using the obtained diffraction spectra of the second phase, the physical phases corresponding to each diffraction spectrum are identified by combining them with information on the elemental composition of the second phase. After confirming that the phase structure at the position is an L or L compound by comparing it with a physical phase card, the width of the L or L compound is measured using software. In Figure 1, 10 represents the tungsten matrix, and 20 represents L or a compound of L. The average width of L or a compound of L is calculated by measuring the width of multiple Ls and averaging them. Note that for ease of explanation, Figure 1 shows a partial cross-section of the tungsten alloy wire sheet, rather than the entire sheet.

[0100] The dislocation density test method was as follows: A sheet was cut along the axial direction of a tungsten alloy wire using a focused ion beam cutting apparatus. This sheet was then placed in a high-resolution transmission electron microscope to directly observe the lattice pattern and obtain dislocations. The number of dislocation lines passing through the cross-sectional area per unit area was calculated to obtain the dislocation density.

[0101] [Table 3] Here, " / " indicates that there is no matching data.

[0102] From the test results in Tables 2 and 3, the following was found: The tungsten alloy wire according to the embodiment of this application has a tensile strength of 5000 MPa or more for wire diameters of 20 to 60 μm, and the tensile strength increases accordingly as the wire diameter decreases. At a wire diameter of 28 μm, the tensile strength reaches 7000 MPa or more. The number of surface defects in the wire is less than 10 per 100 m in all cases. At 28 μm, L or L compounds are present linearly, and their average radial width is less than 4 nm in all cases, the average radial width of the tungsten crystal grains is less than 80 nm, and the dislocation density of the wire is 5 × 10⁻¹⁶ 9 / mm 2 If the number of L or L compounds in the wire is greater than γ, then 3 ≤ γ ≤ 10.

[0103] The following was found from comparing Comparative Examples 1.1 and 1.2 with Example 1.1. Compared to existing processes, the method for manufacturing tungsten alloy wire according to the present invention can effectively improve the tensile strength of the wire. This is because, during high-temperature sintering and recrystallization annealing, the second phase of element L coalesces and grows, increasing the average radial width of the element L. Furthermore, during subsequent pressurizing, the second phase particles cause more cracks and breaks, affecting the mechanical strength and workability of the tungsten alloy wire. With the rapid increase in cracks, the number of breaks during wire drawing increases significantly. From the data in Table 3, it was found that with the rapid increase in the number of surface defects in the wire, the workability of the wire decreases, and as a result, the average length of wire per coil decreases significantly.

[0104] The following was found from comparing Comparative Example 1.3 with Example 1.1. When the Z element content in the tungsten alloy exceeds 0.25 wt%, the Z element forms a solid solution with W, effectively increasing the lattice strain of tungsten, accelerating the deformation rate of the tungsten wire, and thereby improving the tensile strength of the tungsten wire. However, if the amount of Z element introduced is too high, the dislocation density of the tungsten alloy wire increases significantly during the deformation process, resulting in rapid work hardening of the tungsten alloy wire, making it difficult to process the wire to a diameter of 60 μm or less.

[0105] The following was found from comparing Comparative Example 1.4 with Example 1.1. If the total content of the two L-elements in the tungsten alloy exceeds 1.1 wt%, the amount of the second phase in the tungsten alloy wire is too high. The ratio γ of the number of second phases to the number of tungsten crystal grains becomes too high, resulting in insufficient bonding between the crystal grains of the tungsten alloy wire. Furthermore, the increase in the number of second phases significantly increases the difficulty of dislocation sliding, making it difficult to process the tungsten alloy wire, and preventing it from being processed to a thickness of 60 μm or less.

[0106] The following was found from comparing Comparative Example 2.1 with Example 1.1. Compared to the embodiments of this application, when deionized water is used as the solvent for element L in the wet doping step, the size of the tungsten crystal grains and the average width of L in the radial direction increase at the same wire diameter level. This is because the dispersibility of the element L compound in the doping process is insufficient, leading to localized concentration of element L during nucleation of the tungsten powder in the subsequent reduction process. After high-temperature sintering, these element L compounds grow by engulfing each other, resulting in a significant decrease in the actual strengthening and refinement effect of the tungsten crystal grains and a substantial increase in the number of surface defects in the manufactured tungsten alloy wire.

[0107] The following was found from comparing Comparative Example 2.2 with Example 1.1. In the powdering step, when the alloy powder is prepared by primary reduction, the average width of L in the radial direction increases significantly, resulting in a significant decrease in the tensile strength of the wire compared to Example 1.1, and a significant increase in the number of surface defects in the manufactured tungsten alloy wire. This is because tungsten alloy powder produced by high-temperature primary reduction is prone to localized non-uniform doping during reduction and aggregation / concentration after reduction, leading to microscopic non-uniformity in the subsequent doping of the alloy powder, which causes defects in the subsequent pressurizing process and reduces the risk of wire breakage.

[0108] The following was found from comparing Comparative Example 2.3 with Example 1.1. In the pressurizing step, when a compression ratio of 10-30% from the conventional wire drawing pass is applied, the average radial width L of the resulting wire of each standard is relatively large, and the average grain size width of tungsten crystals increases significantly. As a result, cracks and breaks caused by second-phase particles increase in the subsequent pressurizing process, which in turn affects the tensile strength. As is clear from this, in this application, a large compression ratio of 35% to 60% is adopted for processing the tungsten alloy wire, which leads to greater fiber development in the resulting wire, which is advantageous for the linearization of L elements and their compounds during processing, and also increases the deformation rate of the tungsten grain boundaries, thereby improving the tensile strength of the wire.

[0109] The number of surface defects and the average length of the tungsten alloy wires obtained in Examples and Comparative Examples 2.4.1 to 2.4.4 were measured, and the measurement results are shown in Table 4.

[0110] [Table 4]

[0111] The following was found by comparing Comparative Examples 2.4.1 to 2.4.4 with Example 1.1. If the mass percentage of surface oxides in the wire during the annealing step is less than 1%, the tungsten alloy wire will have an insufficient surface lubrication layer, requiring multiple wire drawing processes after annealing. As a result, the surface hardening rate of the wire will increase significantly, and the number of surface defects will increase substantially. Ultimately, it will become impossible to stably produce products of the required length. In this application, the mass percentage of surface oxides in the tungsten alloy wire is 1% or more.

[0112] Finally, I would like to explain the following. The embodiments described above are used solely to illustrate the technical solutions of the present application and are not intended to limit them. While the present application has been described in detail with reference to the embodiments described above, those skilled in the art should understand that the technical solutions described in the embodiments above may be modified, or some or all of their technical features may be replaced with equivalents. These modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. It is a tungsten alloy wire, The tungsten alloy consists of, as elements, L 0.4 to 1.1 wt%, Z 0.001 to 0.25 wt%, the remainder being tungsten and unavoidable impurities, by mass fraction. The aforementioned L is one or more of the following: lanthanum, cerium, praseodymium, neodymium, gadolinium, and erbium. The aforementioned Z includes oxygen and carbon, A tungsten alloy wire characterized in that the wire diameter is 20 to 60 μm, a linear L or L compound exists along the axial direction of the wire, and the average radial width D of the L or L compound is 5 nm or less.

2. In the aforementioned wire, the average width of the tungsten crystal grains in the radial direction is 80 nm or less. The tungsten alloy wire according to claim 1, characterized in that, in the wire, if γ is the number of L or compounds of L divided by the number of tungsten crystal grains, then 3 ≤ γ ≤ 10.

3. In the aforementioned wire, the dislocation density is 5 × 10 ９ / mm ２ The tungsten alloy wire according to claim 1, as described above.

4. When the wire diameter of the aforementioned wire is >50 μm and ≤60 μm, the average radial width D of L or the compound of L is 5 nm or less, and the tensile strength of the wire is 5000 MPa or more. When the wire diameter of the aforementioned wire is >40 μm and ≤50 μm, the average radial width D of L or the compound of L is 4 nm or less, and the tensile strength of the wire is 5500 MPa or more. When the wire diameter of the aforementioned wire is >30 μm and ≤40 μm, the average radial width D of L or the compound of L is 3 nm or less, and the tensile strength of the wire is 6000 MPa or more. When the wire diameter of the aforementioned wire is ≥ 20 μm and ≤ 30 μm, the average radial width D of L or the compound of L is 2 nm or less, and the tensile strength of the wire is 7000 MPa or more. The tungsten alloy wire according to claim 1, characterized in that the number of surface defects in the wire is 10 or less per 100m.

5. A method for producing a tungsten alloy wire according to any one of claims 1 to 4, characterized by comprising wet doping, powdering, pressing, sintering, bloc rolling, and pressure processing.

6. The wet doping step: Blue tungsten oxide powder is uniformly dispersed in deionized water to obtain a blue tungsten oxide suspension, nanoscale compound powder L is uniformly dispersed in an alkaline solution with pH > 11 to form a second suspension, then the solution containing element Z and the second suspension are sequentially sprayed onto the blue tungsten oxide suspension, heated and dried to obtain doped blue tungsten oxide powder. The aforementioned powdering step: The doping blue tungsten oxide powder is reduced to obtain alloy powder A with a particle size of 1.5 to 2.6 μm and alloy powder B with a particle size of 3.8 to 4.5 μm, respectively. Then, alloy powder A and alloy powder B are uniformly mixed to obtain a mixed powder. The aforementioned sintering process: The pre-sintered tungsten rod obtained by pressing is sintered by applying an electric current, and this sintering is carried out in two stages. In the first sintering stage, it is sintered for 30 to 45 minutes at a current intensity of 60% of the tungsten rod's melting current, and then cooled. In the second sintering stage, it is sintered for 40 to 80 minutes at a current intensity of 90% to 92% of the tungsten rod's melting current, resulting in a density of 18.6 g / cm³. ３ The above sintered elementary strips were obtained, The method for manufacturing a tungsten alloy wire according to claim 5, characterized in that the aforementioned pressurizing process is: the alloy rod obtained by the bract rolling is recrystallized and annealed, then forged using a multi-pass continuous rotary forging apparatus to obtain a tungsten rod with a diameter of 2.5 to 4.0 mm, the tungsten rod is subjected to thick wire drawing using wire drawing dies of different specifications, the wire drawing pass is repeated multiple times to achieve a compression ratio of 35% to 60%, and a thick tungsten alloy wire with a diameter of 0.3 to 0.5 mm is obtained.

7. In the wet doping process, the method for producing the blue tungsten oxide powder involves sending ammonium paratungstate to a reduction furnace and reducing it at 400-600°C under the protection of hydrogen and nitrogen gases to obtain the blue tungsten oxide powder, wherein the thickness of the ammonium paratungstate powder material layer is less than 10 mm, the flow rate of hydrogen gas in the reduction furnace is 20-40 L / min, the flow rate of nitrogen gas is 80-160 L / min, the oxygen index of the blue tungsten oxide powder is 2.85 ± 0.05, and the ammonium tungsten bronze phase component is more than 80%. The method for producing a tungsten alloy wire according to claim 6, characterized in that, in the pulverization step, the method for reducing alloy powder A is to first reduce the doped blue tungsten oxide powder in a hydrogen reduction furnace at 500 to 800°C, and then perform a secondary reduction in the hydrogen reduction furnace to obtain alloy powder A with a particle size of 1.5 to 2.6 μm, and the method for reducing alloy powder B is to reduce the doped blue tungsten oxide powder in a hydrogen reduction furnace at 700 to 1100°C to obtain alloy powder B with a particle size of 3.8 to 4.5 μm, and the alloy powder A and alloy powder B are uniformly mixed in a mass ratio of 1:(1 to 2).

8. The method for manufacturing a tungsten alloy wire according to claim 6, characterized in that, in the pressure processing step, the alloy rod obtained by the bract rolling is heated to 2000 to 2600°C in a medium / high frequency induction coil to recrystallize and anneal, and when drawing the tungsten alloy wire to a diameter of 0.3 to 0.5 mm, it is necessary to perform annealing, the annealing temperature is set to 1300 to 1800°C, and after annealing, the tungsten alloy wire is cooled in an oxygen atmosphere, and after annealing, the drawing is repeated multiple times to obtain tungsten alloy wires of different diameter specifications.

9. Use of tungsten alloy wire according to any one of claims 1 to 4 in the fields of cutting, cut protection, cables, screen printing, ropes, or spinning.

10. Use of a tungsten alloy wire according to any one of claims 1 to 4 in cutting semiconductor materials.

Images