Alloy wire and its preparation method and application

Abstract

The present invention relates to the technical field of tungsten alloy materials, and in particular to an alloy wire, a preparation method thereof, and an application thereof. The alloy wire is made of a tungsten alloy, the components of which include tungsten, aluminum, oxygen, and lanthanum; the lanthanum content is 0.3wt% to 1.2wt%, the oxygen content is 0.10 to 0.95wt%, the mass ratio of the lanthanum to the aluminum is (3 to 10):1, and the remainder is tungsten and unavoidable impurities; when the wire diameter of the alloy wire is 100μm or less, the tensile strength of the alloy wire is above 4600MPa. The present invention provides an alloy wire having higher strength, toughness, and fineness.

Description

Technical Field

[0001] The present invention relates to the technical field of tungsten alloy materials, and in particular to an alloy wire and a preparation method and application thereof. Background Art

[0002] High-carbon steel wire and tungsten wire are known to have relatively high strength and hardness. However, the tensile strength of existing high-carbon steel wire is generally below 4500 MPa, while the diameter is greater than 50 μm, which has reached the processing limit and cannot be processed to a finer diameter.

[0003] Conventional tungsten wire generally has a tensile strength below 4000 MPa, poor toughness, and complex production processes, making it extremely difficult to manufacture effectively. Commercially available tungsten-rhenium wire can reach 5000 MPa with a 25μm diameter, but its push-pull performance is poor and its toughness is insufficient. To improve the overall performance of tungsten alloys, some have proposed doping the tungsten matrix with rare earth oxides to achieve enhanced tensile strength. For example, Chinese patent document CN113186438A discloses an alloy wire, preparation method, and application thereof. The tungsten alloy comprises tungsten and lanthanum oxides, with a lanthanum oxide content of 0.1wt% to 2.0wt%. With a wire diameter of 60μm, the tensile strength is 4200-5300 MPa, and with a wire diameter of 40μm, the tensile strength is 4800-5800 MPa. However, given the increasingly sophisticated processing requirements, further refinement of the wire diameter is needed to improve the tensile strength of the wire. In addition, in order to improve the tensile strength of the wire, the addition amount of rare earth oxides such as lanthanum needs to be increased to a certain higher level. Compared with other ordinary metals, rare earth metals such as lanthanum and yttrium are more expensive and have higher costs.

[0004] Therefore, there is an urgent need for a high-strength and high-toughness thinned wire that is suitable for mass production, has high tensile strength, and has low preparation cost, so that it can meet various practical application requirements in application fields such as cutting of high-hardness materials - such as semiconductor materials sapphire, silicon carbide, silicon wafers, magnetic materials, high-precision equipment, and cables or ropes for high-temperature furnace traction. Summary of the Invention

[0005] In order to solve the problem of the performance defects of the existing high-strength tungsten alloy wire mentioned in the above background technology, the present invention provides an alloy wire, and its technical solution is as follows:

[0006] The alloy wire is made of tungsten alloy, and the components of the tungsten alloy include tungsten, aluminum, oxygen and lanthanum; the lanthanum content is 0.3wt% to 1.2wt%, the oxygen content is 0.10 to 0.95wt%, and the mass ratio of the lanthanum to the aluminum is (3 to 10):1; the remainder is tungsten and unavoidable impurities. When the wire diameter of the alloy wire is 100μm or less, the tensile strength of the alloy wire is above 4600MPa.

[0007] In some embodiments, when the wire diameter of the alloy wire is 60 μm or less, the tensile strength of the alloy wire is greater than 5100 MPa, and the elastic limit strength of the alloy wire is greater than 3000 MPa; and / or, when the wire diameter of the alloy wire is 40 μm or less, the tensile strength of the alloy wire is greater than 5800 MPa, and the elastic limit strength of the alloy wire is greater than 3300 MPa; and / or, when the wire diameter of the alloy wire is 25 μm or less, the tensile strength of the alloy wire is greater than 6000 MPa; the elastic limit strength of the alloy wire is greater than 3600 MPa.

[0008] In some embodiments, the lanthanum element is present in the alloy wire in the form of lanthanum oxide.

[0009] The present invention also provides a method for preparing the alloy wire as described above, which comprises the steps of doping, reducing and pulverizing, pressing, sintering, blanking and pressure processing.

[0010] In some embodiments, the process of the doping step is as follows: blue tungsten powder is uniformly dispersed in deionized water to obtain a blue tungsten suspension, lanthanum oxide powder and aluminum nitrate powder are uniformly dispersed in an alkaline solution with a pH greater than 11 to form a first suspension, and the first suspension is sprayed into the blue tungsten suspension. After spraying, the blue tungsten powder is dried to obtain doped blue tungsten powder; wherein, the preparation method of the blue tungsten powder is: ammonium paratungstate is introduced into a reduction furnace, and reduced at 400-600°C under hydrogen and nitrogen protection to obtain doped blue tungsten powder; wherein, the thickness of the ammonium paratungstate powder layer is less than 10 mm, the hydrogen flow rate in the reduction furnace is 20-40 L / min, the nitrogen flow rate is 80-160 L / min, the oxygen index of the blue tungsten powder is 2.85±0.05, and the ammonium tungsten bronze phase component is greater than 80%.

[0011] In some embodiments, in the doping step, the drying is carried out in stages, which includes at least two temperature stages, and the two temperature stages are divided by 80°C and 100°C. The drying is first carried out at a temperature less than or equal to 80°C, and then at a temperature greater than or equal to 100°C.

[0012] In some embodiments, the staged drying includes a first drying stage and a second drying stage, the temperature of the first drying stage is 50-70°C, and the temperature of the second drying stage is 100-140°C.

[0013] In some embodiments, the process of the pressure processing step is: the alloy rod obtained by the blanking is recrystallized and annealed, and then forged into a tungsten rod with a diameter of 2.5 to 4.0 mm through a multi-pass continuous rotary forging device; the tungsten rod is drawn through drawing dies of different specifications to obtain a tungsten alloy wire of the required diameter; wherein, the tungsten alloy wire needs to be annealed when it is drawn to a diameter of 0.3 to 0.5 mm, and the annealing temperature is 1300 to 1800°C. After annealing, the tungsten alloy wire is cooled in an oxygen environment; the annealed and cooled wire is drawn through drawing dies of different specifications, and the drawing is repeated multiple times to be drawn to the required wire diameter.

[0014] In some embodiments, during the press working, the alloy rod obtained by the blanking is heated to 2000-2600° C. for recrystallization annealing.

[0015] The present invention also provides applications of the tungsten alloy wire described above in the fields of material cutting, cables, screen printing, ropes, or textiles.

[0016] Compared with the prior art, the alloy wire provided by the present invention has the following beneficial effects:

[0017] The present invention provides an alloy wire with higher strength, toughness and fineness, which has the following properties:

[0018] 1. When the wire diameter is 100μm or less, the tensile strength reaches above 4600MPa;

[0019] 2. When the wire diameter of the alloy wire is 60 μm or less, the elastic limit strength of the alloy wire is greater than 3000 MPa; the tensile strength of the alloy wire is greater than 5100 MPa. DETAILED DESCRIPTION

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0021] The present invention provides an alloy wire:

[0022] 1. The plan is:

[0023] The alloy wire is made of tungsten alloy, and the components of the tungsten alloy include tungsten, aluminum, oxygen and lanthanum; the lanthanum content is 0.3wt% to 1.2wt%, the oxygen content is 0.10 to 0.95wt%, the mass ratio of the lanthanum element to the aluminum element is (3 to 10):1, and the remainder is tungsten and unavoidable impurities. Preferably, the tungsten content is 95wt% or more, wherein the lanthanum element exists in the alloy wire in the form of lanthanum oxide.

[0024] Wherein, the tungsten alloy matrix contains lanthanum and aluminum:

[0025] The lanthanum oxide is preferably lanthanum oxide (La2O3). The performance of the alloy wire can be improved by increasing the lanthanum oxide content within a certain content range. On the basis of adding lanthanum oxide, a certain proportion of aluminum is added. Lanthanum oxide plays a role of dispersion strengthening in the tungsten alloy wire. The addition of an appropriate amount of Al is conducive to the formation of uniform dispersed particles, thereby further improving the strength of the tungsten wire under thin wire diameter.

[0026] The smaller the wire diameter of the alloy wire composed of aluminum, lanthanum oxide and tungsten, the relatively stronger the tensile strength; that is, by using tungsten alloy wire composed of aluminum, lanthanum and tungsten, saw wires, cables, etc. with small wire diameter and high tensile strength can be achieved.

[0027] 2. The properties of the prepared tungsten alloy wire are as follows:

[0028] The tensile strength of the alloy wire is above 4600 MPa, and can be above 5100 MPa, or even 5800 MPa or 6000 MPa;

[0029] In addition, the elastic limit strength of the alloy wire is greater than 3000 MPa. For example, the elastic limit strength of the alloy wire may be greater than 3300 MPa, or even greater than 3600 MPa or even greater than 4000 MPa.

[0030] The alloy wire has a diameter of 100 μm or less. For example, the alloy wire may have a diameter of 100 μm, 80 μm, or even 60 μm, 40 μm, 25 μm, 20 μm, or 10 μm. The alloy wire diameter may be uniform or non-uniform, and may also vary by several percentages, such as 1%, depending on the location.

[0031] In particular, the wire diameter of the alloy wire can be 60 μm or less, so the alloy wire is flexible and can be easily bent, thereby allowing the alloy wire to be easily wound.

[0032] Specifically, for example, the wire diameter of the alloy wire is 100 μm or less, and the tensile strength of the alloy wire is 4600 MPa or more;

[0033] The wire diameter of the alloy wire is 60 μm or less, the tensile strength of the alloy wire is 5100 MPa or more, and the elastic limit strength of the alloy wire is 3000 MPa or more;

[0034] The wire diameter of the alloy wire is 40 μm or less; the tensile strength of the alloy wire is 5800 MPa or more; the elastic limit strength of the alloy wire is 3300 MPa or more;

[0035] The wire diameter of the alloy wire is 25 μm or less; the tensile strength of the alloy wire is greater than 6000 MPa; and the elastic limit strength of the alloy wire is greater than 3600 MPa.

[0036] Preferably, the mass ratio of the lanthanum element to the aluminum element is (5-7):1; the properties of the tungsten alloy wire are as follows:

[0037] When the wire diameter of the alloy wire is 100 μm or less, the tensile strength of the alloy wire is greater than 5000 MPa, and may also be greater than 5150 MPa.

[0038] When the wire diameter of the alloy wire is 60 μm or less, the tensile strength of the alloy wire is 5500 MPa or more, and may be 5800 MPa or more; the elastic limit strength of the alloy wire is 3250 MPa or more, and may be 3900 MPa or more;

[0039] When the wire diameter of the alloy wire is 40 μm or less, the tensile strength of the alloy wire is 6300 MPa or more, and may be 6500 MPa or more; the elastic limit strength of the alloy wire is 3600 MPa or more, and may be 4100 MPa or more;

[0040] When the wire diameter of the alloy wire is 25 μm or less, the tensile strength of the alloy wire is greater than 6500 MPa, and may be greater than 6900 MPa; the elastic limit strength of the alloy wire is greater than 3900 MPa, and may be greater than 4200 MPa.

[0041] 3. In addition, for the addition of other components in tungsten alloy wire:

[0042] The lanthanum oxide may also be a lanthanum-metal composite oxide, such as LSCO.

[0043] In addition, the tungsten alloy may also contain trace amounts of carbides, other rare elements, metals, and non-metallic elements. For example, the carbides include TiC and ZrC, the other rare elements include rhenium, etc., the non-metallic elements include C, etc., and the metal elements include potassium, molybdenum, iron, etc.; among them, the potassium content is less than 80ppm. The addition of an appropriate amount of potassium can improve the high-temperature performance of the material, but too high a content will affect the processing performance and cause cracks and wire breakage.

[0044] 4. The present invention provides a method for preparing an alloy wire:

[0045] The steps of the preparation method include doping and powdering, pressing, sintering, blanking, pressure processing, etc.

[0046] 4.1 Doping steps:

[0047] The blue tungsten powder is uniformly dispersed in deionized water to obtain a blue tungsten suspension, lanthanum oxide powder and aluminum nitrate powder are uniformly dispersed in an alkaline solution with a pH greater than 11 to form a first suspension, and the first suspension is sprayed into the blue tungsten suspension. After spraying, the mixture is dried to obtain doped blue tungsten powder;

[0048] The preparation method of the blue tungsten powder comprises: feeding ammonium paratungstate into a reduction furnace and reducing it at 400-600° C. under the protection of hydrogen and nitrogen to obtain doped blue tungsten powder; wherein the thickness of the ammonium paratungstate powder layer is less than 10 mm, the hydrogen flow rate in the reduction furnace is 20-40 L / min, the nitrogen flow rate is 80-160 L / min, the oxygen index of the blue tungsten powder is 2.85±0.05, and the ammonium tungsten bronze phase component is greater than 80%;

[0049] The drying adopts a staged drying method, which includes at least two temperature stages, with 80°C and 100°C as the dividing line between the two temperature stages. The drying is first carried out at a temperature less than or equal to 80°C, and then at a temperature greater than or equal to 100°C. The staged heating and drying adopts a low-temperature drying method followed by a high-temperature drying method. That is, the drying is carried out at a temperature less than or equal to 80°C, so that the lanthanum salt particles are slowly precipitated and the number of nuclei is large. The drying is then carried out at a temperature greater than or equal to 100°C, so that the lanthanum salt particles with a large number of particles do not have time to merge and grow, thereby significantly refining the particle size.

[0050] The staged drying includes at least two temperature stages, with 80°C and 100°C as the dividing line between the two temperature stages. The drying is first carried out at 80°C or below, and then at a temperature greater than or equal to 100°C. For example, the drying is first carried out at 50-70°C for 3h-7h, and then at 100-140°C for 4h-6h.

[0051] It is understood that within the two temperature stages divided by 80°C and 100°C, heating and drying can be performed in multiple temperature gradients or multiple temperature stages, for example, first drying at 60°C for 2 hours, then drying at 80°C for 2 hours, and then drying at 120°C.

[0052] It should be noted that the above-described embodiments only express several implementation methods of the present invention. For ordinary technicians in this field, without departing from the concept of the present invention, several adjustments and changes to the temperature stages can be made, which all fall within the scope of protection of the present invention.

[0053] 4.2 Pressure processing steps:

[0054] The alloy rod obtained by the blanking is subjected to recrystallization annealing, and then forged into a tungsten rod with a diameter of 2.5 to 4.0 mm through a multi-pass continuous rotary forging device; preferably, the alloy rod obtained by the blanking is heated to 2000 to 2600° C. through a medium / high frequency induction coil for recrystallization annealing.

[0055] The tungsten rod is drawn through drawing dies of different specifications to obtain tungsten alloy wires of required diameters; wherein, the tungsten alloy wires need to be annealed when drawn to a diameter of 0.3 to 0.5 mm, and the annealing temperature is 1300 to 1800° C. After annealing, the tungsten alloy wires are cooled in an oxygen environment; the annealed and cooled wires are drawn through drawing dies of different specifications, and the drawing process is repeated multiple times to respectively draw the wires to the required diameters.

[0056] 4.3 In addition to the above-mentioned doping and pressure processing, the reduction powder making, pressing, sintering, and blanking steps in the preparation method are preferably, but not limited to, implemented in the following manner, namely:

[0057] (1) The process of the reduction powder making step: reducing the doped blue tungsten powder into an alloy powder with an average Fisher particle size of 1.0 to 4.0 μm;

[0058] (2) The powder pressing step comprises isostatically pressing the alloy powder into a compact, and pre-sintering the compact in a hydrogen atmosphere;

[0059] Preferably, the powder having an average Fisher particle size of 1.0 μm to 4.0 μm is pressed into a green compact having a single weight of 1.5 kg to 5.0 kg at a pressure of 160 MPa to 260 MPa by isostatic pressing, and the green compact is pre-sintered in a hydrogen atmosphere at a temperature of preferably 1200-1400° C. to increase the green compact strength;

[0060] (3) The sintering step comprises sintering the compact to obtain a sintered compact;

[0061] The sintering temperature is preferably 1800-2400°C, the sintering time is preferably 5-15 hours, and the density is preferably 17.5-18.5 g / cm 3 Sintered billets;

[0062] (4) The process of the blanking step is to use a multi-roll rolling mill to continuously roll the sintered billet with a diameter of 15 mm to 25 mm into an alloy rod with a diameter of 8.0 mm to 12.0 mm at a heating temperature of 1600 to 1700° C.;

[0063] Furthermore, the drawn wire can be electrolytically polished and cleaned to make the surface of the wire smooth; the electrolytic polishing process is performed, for example, by immersing the alloy wire and a counter electrode such as a carbon rod in an electrolyte and passing electricity between the alloy wire and the counter electrode.

[0064] 5. Compared with conventional tungsten alloy wires, the present invention has the following characteristics and advantages:

[0065] (1) The tungsten alloy matrix contains lanthanum oxide and aluminum:

[0066] On the basis of adding lanthanum oxide, a certain content of aluminum is added; lanthanum oxide plays a role of dispersion strengthening in tungsten alloy wire. The addition of appropriate amount of Al is conducive to the formation of uniform dispersed particles, thereby further improving the strength of tungsten wire under thin wire diameter.

[0067] (2) The present invention optimizes the doping process by combining component formulations:

[0068] In the preparation process of blue tungsten in the present invention, a hydrogen-nitrogen mixed gas is used as a reducing protective medium, and the properties of the discharged blue tungsten powder are controlled by the thickness of the material layer and the size and flow direction of the hydrogen gas. Specifically, the oxygen index and the ammonium tungsten bronze phase ratio of the blue tungsten are controlled, and the blue tungsten is doped. Since the blue tungsten particles are coarse and there are many surface cracks, it is conducive to the entry of the rare earth solution in the subsequent doping step, thereby improving the doping effectiveness and enhancing the tensile properties of the wire.

[0069] Blue tungsten powder is uniformly dispersed in deionized water to form a blue tungsten suspension. Lanthanum compound powder and aluminum compound powder are uniformly dispersed in an alkaline solution with a pH greater than 11 to form a first suspension. The first suspension is then sprayed into the blue tungsten suspension and heated and dried to obtain doped blue tungsten powder. Fine particles are directly and evenly doped into the blue tungsten powder by preparing a suspension of lanthanum and aluminum compounds. The fine particles act as heterogeneous crystal nuclei and co-crystallize with tungsten particles. This produces a tungsten alloy powder with a more uniform dispersion distribution, a wider range of dispersed particles, and more stable and reliable tungsten material performance. When using solid-liquid doping, drying is performed in a staged drying mode, first at low temperature and then at high temperature. This drying method significantly refines the particle size of the lanthanum compound. By adjusting the doping drying temperature to control the nucleation and crystallization rates of the lanthanum compound, the lanthanum particle crystals on the doped blue tungsten particles are finer.

[0070] Therefore, the particle size of lanthanum compounds on the surface of tungsten powder particles and the particle size of lanthanum oxides in sintered billets produced by the present invention are both finer than those produced by traditional methods. The particle size of lanthanum oxides is small and more evenly distributed, and the product performance is more stable.

[0071] (3) The present invention optimizes the pressure process by combining component formulas:

[0072] In the pressure processing step, the present invention performs oxygen cooling treatment on the wire after annealing to increase the content and thickness of the oxide layer on the surface of the tungsten alloy wire, which can effectively improve the wire lubrication layer, thereby improving the drawing conditions, thereby greatly reducing the probability of wire breakage and allowing the wire to be smoothly reduced in diameter.

[0073] Example 1

[0074] The tungsten alloy is composed of lanthanum, aluminum, oxygen, tungsten, and inevitable impurities; the lanthanum content is 1wt%, the aluminum content is 0.333wt%, the oxygen content is 0.787wt%, and the balance is tungsten and inevitable impurities; the preparation steps are as follows:

[0075] Step 1, doping:

[0076] Preparation of blue tungsten: Ammonium paratungstate powder is reduced with hydrogen in a reverse hydrogen continuous reduction furnace at 400°C, 450°C, 500°C, and 560°C (with four temperature zones, and the time for the ammonium paratungstate powder to pass through each temperature zone is 10 minutes). The thickness of the ammonium paratungstate powder layer is 8mm, the hydrogen flow rate is 30L / min, and the nitrogen flow rate is 140L / min. Blue tungsten powder is obtained, with an oxygen index of 2.87 and an ammonium tungsten bronze phase composition of 82%.

[0077] The obtained blue tungsten powder is uniformly dispersed in deionized water to obtain a blue tungsten suspension, wherein the volume ratio of the blue tungsten powder to the deionized water is 1:15; an appropriate amount of nano-scale powders of lanthanum oxide and aluminum nitrate are uniformly dispersed in a sodium hydroxide solution with a pH of 13, and stirred at a high speed of 1500r / min in a high-speed emulsification device to form a first suspension, which is sprayed into the blue tungsten suspension through a vacuum pipe. After the spraying is completed, the blue tungsten suspension is heated and dried, first at a low temperature of 70°C for 4 hours and then at a high temperature of 110°C for 4 hours to obtain a doped blue tungsten powder;

[0078] Step 2, reduction: the material obtained in step 1 is reduced into alloy powder with a particle size of 1.0 to 4.0 μm in a four-temperature zone reduction furnace;

[0079] Step 3: Mixing: Place the materials obtained in step 2 into a powder mixer according to different particle sizes. Mix at a speed of 8 rpm for 80 minutes.

[0080] Step 4, powder pressing: The powders of different particle sizes are pressed into green compacts weighing 3.0 kg at a pressure of 200 MPa using isostatic pressing. The green compacts are then pre-sintered at 1300°C in a hydrogen atmosphere to increase their strength.

[0081] Step 5: High temperature sintering: sinter at 2000℃ for 10h to obtain a density of 18.10g / cm 3 Sintered billets;

[0082] Step 6, blanking: using a multi-roll rolling mill to continuously roll the 20 mm diameter sintered billet into a 10 mm alloy rod at a heating temperature of 1600-1700°C;

[0083] Step 7, press working: The alloy rod obtained in step 6 is heated to 2400° C. by a high-frequency induction coil for recrystallization annealing, and then forged into a tungsten rod with a diameter of 3.0 mm by a multi-pass continuous rotary forging device;

[0084] Step 8: Drawing the tungsten rod through drawing dies of different specifications, repeating the drawing process multiple times with a compression ratio of 35% to 60%, to obtain a tungsten alloy thick wire with a diameter of 0.5 mm;

[0085] Step 9, annealing: annealing the obtained tungsten alloy wire when it is processed to φ0.5mm. After annealing, the tungsten alloy wire is cooled in an oxygen environment. The annealing temperature is 1600°C when the φ0.5mm is large.

[0086] Step 10: Drawing the annealed wire through wire drawing dies of different specifications, and repeating the drawing process multiple times to obtain the desired wire diameter;

[0087] Step 11, electrolytic cleaning: The tungsten alloy wire obtained in step 10 is first electrolyzed in a 22wt% potassium hydroxide solution, which includes 12 sets of AC electrolytic sheets, and then sequentially electrolyzed in 6 sets of 6wt% potassium hydroxide solution, which includes 5 sets of DC electrolytic sheets. The electrolysis speed is 180m / min. After electrolysis, the surface is cleaned with deionized water to obtain white thin tungsten wires of different wire diameters.

[0088] Example 1.2

[0089] The only difference from Example 1.1 is that the components of the tungsten alloy consist of lanthanum, aluminum, oxygen, tungsten and inevitable impurities; the lanthanum content is 0.3wt%, the aluminum content is 0.075wt%, the oxygen content is 0.19wt%, and the balance is tungsten and inevitable impurities; the other preparation processes and conditions are consistent with Example 1.1.

[0090] Example 1.3

[0091] The only difference from Example 1.1 is that the components of the tungsten alloy consist of lanthanum, aluminum, oxygen, tungsten and inevitable impurities; the lanthanum content is 1.2wt%, the aluminum content is 0.12wt%, the oxygen content is 0.428wt%, and the balance is tungsten and inevitable impurities; the other preparation processes and conditions are consistent with Example 1.1.

[0092] Example 1.4

[0093] The only difference from Example 1.1 is that the components of the tungsten alloy consist of lanthanum, aluminum, oxygen, tungsten and inevitable impurities; the lanthanum content is 1wt%, the aluminum content is 0.2wt%, the oxygen content is 0.542wt%, and the balance is tungsten and inevitable impurities; the other preparation processes and conditions are consistent with Example 1.1.

[0094] Example 1.5

[0095] The only difference from Example 1.1 is that the components of the tungsten alloy consist of lanthanum, aluminum, oxygen, tungsten and inevitable impurities; the lanthanum content is 1 wt %, the aluminum content is 0.143 wt %, the oxygen content is 0.436 wt %, and the balance is tungsten and inevitable impurities; the other preparation processes and conditions are consistent with Example 1.1.

[0096] Comparative Example 1.1

[0097] The only difference from Example 1.1 is that in the annealing step, the obtained tungsten alloy wire is annealed when it is processed to φ0.5 mm, and then cooled in air; other preparation conditions are consistent with Example 1.1.

[0098] Comparative Example 1.2

[0099] The only difference between it and Example 1.1 is that: in the doping step, the first suspension is sprayed into the blue tungsten suspension through a vacuum pipe, and after the spraying is completed, it is steam-dried at a temperature of 110°C for 4 hours to obtain doped blue tungsten powder; other preparation conditions are consistent with Example 1.1.

[0100] Comparative Example 1.3

[0101] The only difference between it and Example 1.1 is that: in the doping step, appropriate amounts of nano-scale powders of lanthanum oxide and aluminum nitrate are evenly dispersed in deionized water, and then added to the above-mentioned blue tungsten suspension and stirred evenly, first dried at a low temperature of 70°C for 4 hours and then dried at a high temperature of 110°C for 4 hours to obtain doped blue tungsten powder; other preparation conditions remain consistent with Example 1.1.

[0102] Comparative Example 1.4

[0103] In the doping step, ammonium paratungstate is sequentially reduced with hydrogen in a continuous hydrogen reduction furnace at 400°C, 450°C, 500°C, and 560°C (four temperature zones are provided, and the time for the ammonium paratungstate powder to pass through each temperature zone is 10 minutes). The hydrogen flow rate is 60 L / min, and the obtained blue tungsten powder has an oxygen index of 2.80 and an ammonium tungsten bronze phase accounting for 58%. Other preparation conditions are consistent with those in Example 1.1.

[0104] Comparative Example 1.5

[0105] The only difference from Example 1.1 is that the components of the tungsten alloy consist of lanthanum, aluminum, oxygen, tungsten and inevitable impurities; the lanthanum content is 0.06wt%, the aluminum content is 0.333wt%, the oxygen content is 0.625wt%, and the balance is tungsten and inevitable impurities; the other preparation processes and conditions are consistent with Example 1.1.

[0106] Comparative Example 1.6

[0107] The only difference from Example 1.1 is that the components of the tungsten alloy consist of lanthanum, aluminum, oxygen, tungsten and inevitable impurities; the lanthanum content is 2.3wt%, the aluminum content is 0.333wt%, the oxygen content is 1.012wt%, and the balance is tungsten and inevitable impurities; the other preparation processes and conditions are consistent with Example 1.1.

[0108] Comparative Example 1.7

[0109] The only difference from Example 1.1 is that the components of the tungsten alloy consist of lanthanum, aluminum, oxygen, tungsten and inevitable impurities; the lanthanum content is 1 wt %, the aluminum content is 0.067 wt %, the oxygen content is 0.296 wt %, and the balance is tungsten and inevitable impurities; the other preparation processes and conditions are consistent with Example 1.1.

[0110] Comparative Example 1.8

[0111] The only difference from Example 1.1 is that the components of the tungsten alloy consist of lanthanum, aluminum, oxygen, tungsten and inevitable impurities; the lanthanum content is 1 wt %, the aluminum content is 1 wt %, the oxygen content is 2.018 wt %, and the balance is tungsten and inevitable impurities; the other preparation processes and conditions are consistent with Example 1.1.

[0112] Comparative Example 1.9

[0113] The only difference from Example 1.1 is that the components of the tungsten alloy consist of lanthanum, oxygen, tungsten and inevitable impurities; the lanthanum content is 1 wt %, the oxygen content is 0.173 wt %, and the balance is tungsten and inevitable impurities; aluminum nitrate is not added during the doping process in step 1, and the other preparation processes and conditions are consistent with Example 1.1.

[0114] Comparative Example 1.10

[0115] The only difference from Example 1.2 is that the components of the tungsten alloy consist of lanthanum, oxygen, tungsten and inevitable impurities; the lanthanum content is 0.3wt%, the oxygen content is 0.052wt%, and the balance is tungsten and inevitable impurities; aluminum nitrate is not added during the doping process in step 1, and the other preparation processes and conditions are consistent with Example 1.1.

[0116] Comparative Example 1.11

[0117] The only difference from Example 1.1 is that the components of the tungsten alloy consist of lanthanum, oxygen, tungsten and inevitable impurities; the lanthanum content is 1.33wt%, the oxygen content is 0.23wt%, and the balance is tungsten and inevitable impurities; aluminum nitrate is not added during the doping process in step 1, and the other preparation processes and conditions are consistent with Example 1.1.

[0118] Comparative Example 1.12

[0119] The only difference from Example 1.1 is that the components of the tungsten alloy consist of yttrium, aluminum, oxygen, tungsten and inevitable impurities; the yttrium content is 1 wt %, the aluminum content is 0.333 wt %, the oxygen content is 0.884 wt %, and the remainder is tungsten and inevitable impurities; yttrium oxide is used instead of lanthanum oxide during the doping process in step 1, and the other preparation processes and conditions are consistent with Example 1.1.

[0120] Comparative Example 1.13

[0121] The only difference from Example 1.1 is that the components of the tungsten alloy consist of zirconium, aluminum, oxygen, tungsten and inevitable impurities; the zirconium content is 1 wt %, the aluminum content is 0.333 wt %, the oxygen content is 0.966 wt %, and the balance is tungsten and inevitable impurities; zirconium oxide is used instead of lanthanum oxide during the doping process in step 1; other preparation processes and conditions are consistent with Example 1.1.

[0122] It should be noted that the specific parameters or some commonly used reagents in the above embodiments are specific embodiments or preferred embodiments under the concept of the present invention, and are not intended to limit the present invention; those skilled in the art can make adaptive adjustments within the concept and protection scope of the present invention.

[0123] The tensile strength and elastic limit strength of wires of different specifications (0.1 mm, 0.06 mm, 0.04 mm, and 0.025 mm) obtained in the examples and comparative examples were tested using the following methods.

[0124] The tensile strength test method is as follows: a standard tensile testing machine is used to clamp a 200 mm long tungsten wire and load one end at a constant speed to obtain tensile strength data and elastic limit strength;

[0125] The tensile strength is calculated by the following formula (1):

[0126] σ=F / S……(1)

[0127] Where, F is the breaking force, N; S is the original cross-sectional area, mm.

[0128] The tensile strength and elastic limit strength test results of the embodiments and comparative examples are shown in Table 1 below:

[0129] Table 1

[0130]

[0131]

[0132] It should be noted that in Table 1, “\” indicates wire specifications that cannot be further processed.

[0133] As can be seen from Table 1, the alloy wire provided by the present invention has better performance due to the addition of aluminum and lanthanum in a specific ratio. With further process optimization, large-scale production of alloy wires with finer specifications, higher strength and better toughness can be achieved.

[0134] Therefore, the alloy wire provided by the present invention or the alloy wire prepared by the preparation method provided by the present invention can be used in the cutting processing field used for conventional tungsten wire, such as sawing wire, and making metal mesh by weaving the wire into warp and weft.

[0135] The saw wire can be used for cutting a variety of materials, such as hard surface materials such as silicon wafers, magnetic materials, and semiconductor materials, and the semiconductor materials include sapphire, silicon carbide and other materials, or used in conjunction with related cutting devices for cutting. Due to its excellent performance in the application of cutting wire, it can effectively improve its cutting quality and cutting efficiency. The metal mesh can be used for screen printing, for inspection probes, or for catheter wires, etc.

[0136] It should be noted that:

[0137] In practical applications in the field of cutting, the alloy wire provided by the present invention can be used as a busbar, and diamond particles or the like can be electroplated or brazed thereon for use in cutting hard surface materials including silicon wafers, sapphire, silicon carbide and other third-generation semiconductor materials, magnetic materials, and the like;

[0138] Screen printing is widely used in the manufacture of printed circuit boards, thick-film integrated circuits, solar cells, resistors, capacitors, piezoelectric elements, photosensitive elements, thermistors, liquid crystal display elements, etc., and the metal mesh formed by the alloy wire provided by the present invention can also be used for screen printing to replace stainless steel wire, for example, to replace small-sized screens below 18μm.

[0139] Moreover, based on the high tensile strength, elastic limit strength, good electrical conductivity and mechanical properties of the alloy wire provided by the present invention, the alloy wire can be suitable for the application of alloy wires in the field of cables and ropes for medical / industrial precision instruments, for example, in the application of cables / ropes on various mechanical equipment. Such cables can provide the highest strength and longest life, such as in minimally invasive surgical instruments or articulated systems, bearing high loads and bending loads.

[0140] The alloy wire provided by the present invention can well meet the technical requirements of the "pulling system" rope, such as high strength, high tension, non-magnetic, high temperature resistance, and excellent verticality, so that it can be used in smelting, casting, single crystal furnace and other smelting industries, such as high-temperature furnace traction ropes;

[0141] At the same time, due to its excellent flexibility and wear resistance as well as excellent tensile strength and fatigue resistance, the alloy wire can be used to make micro-mechanical wire ropes used in modern surgical robots.

[0142] In addition, the above alloy wires can be used to drive the movement of human arms, elbows and wrists, and tungsten alloy wires can be used to drive the skeletal muscles of surgeons.

[0143] Moreover, as the loads that wire ropes bear in the application of medical robots and medical devices have become increasingly heavier, their structures have been continuously optimized and improved. The previously commonly used 1×7, 7×7, and 7×19 structures have been replaced by more sophisticated and complex twisted wire ropes (such as 7×37, 19×19, and 19×37). Not only have they improved the tensile strength of their predecessors, but they have also added high modulus and excellent flexibility to meet the more stringent application requirements of today's surgical instruments. What's more worth mentioning is that the production of a wire rope with a half-millimeter diameter and a 19×37 structure requires a filament with a diameter of only 0.0005 inches = 12.7μm, a fineness that is almost invisible to the naked eye.

[0144] In addition, based on the characteristics of the alloy wire provided by the present invention, such as lightness, high strength, and high toughness, it can also be applied to technical fields such as textiles, such as cut-resistant protective gloves and protective clothing. The alloy wire has great advantages in being used in cut-resistant safety protective products. The common specifications used in the existing process for directly weaving tungsten wire and yarn into gloves are 18.5μm, 30μm, and 40μm. The alloy wire provided by the present invention can also be processed to finer specifications, the finest of which can reach 3μm, making the product have better softness and lighter weight. While improving the protection level, it is more comfortable and flexible to wear and suitable for a variety of labor safety protection occasions. The strength of high-strength fine tungsten wire is more than twice that of stainless steel wire. The excellent design can increase the cut resistance level by at least 2 levels, so that its grade assessment reaches the high protection level of American standard A6-A9 and European standard F level. The alloy wire provided by the present invention can meet the corresponding requirements in terms of diameter, tensile strength and toughness.

[0145] Finally, it should be noted that:

[0146] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An alloy wire, characterized in that: The alloy wire is made of tungsten alloy, and the components of the tungsten alloy include tungsten, aluminum, oxygen and lanthanum; The lanthanum content is 0.3wt% to 1.2wt%, the oxygen content is 0.10wt% to 0.95wt%, the mass ratio of the lanthanum element to the aluminum element is (3 to 10):1, and the balance is tungsten and unavoidable impurities; When the wire diameter of the alloy wire is 60 μm or less, the tensile strength of the alloy wire is 5100 MPa or more; And / or, when the wire diameter of the alloy wire is 40 μm or less, the tensile strength of the alloy wire is 5800 MPa or more; And / or, when the wire diameter of the alloy wire is 25 μm or less, the tensile strength of the alloy wire is greater than 6000 MPa.

2. The alloy wire according to claim 1, characterized in that: When the wire diameter of the alloy wire is 60 μm or less, the tensile strength of the alloy wire is 5100 MPa or more, and the elastic limit strength of the alloy wire is 3000 MPa or more; And / or, when the wire diameter of the alloy wire is 40 μm or less, the tensile strength of the alloy wire is 5800 MPa or more, and the elastic limit strength of the alloy wire is 3300 MPa or more; And / or, when the wire diameter of the alloy wire is 25 μm or less, the tensile strength of the alloy wire is greater than 6000 MPa; the elastic limit strength of the alloy wire is greater than 3600 MPa.

3. The alloy wire according to claim 1, wherein: The lanthanum element exists in the alloy wire in the form of lanthanum oxide.

4. A method for preparing the alloy wire according to any one of claims 1 to 3, characterized in that: Including doping, reduction powder making, pressing, sintering, blanking and pressure processing steps; The process of the doping step is as follows: The blue tungsten powder is uniformly dispersed in deionized water to obtain a blue tungsten suspension, lanthanum oxide powder and aluminum nitrate powder are uniformly dispersed in an alkaline solution with a pH greater than 11 to form a first suspension, and the first suspension is sprayed into the blue tungsten suspension. After spraying, the mixture is dried to obtain doped blue tungsten powder; The preparation method of the blue tungsten powder is as follows: ammonium paratungstate is introduced into a reduction furnace and reduced at 400-600°C under hydrogen and nitrogen protection to obtain doped blue tungsten powder; wherein the thickness of the ammonium paratungstate powder layer is less than 10mm, the hydrogen flow rate in the reduction furnace is 20-40L / min, the nitrogen flow rate is 80-160L / min, the oxygen index of the blue tungsten powder is 2.85±0.05, and the ammonium tungsten bronze phase component is greater than 80%; In the doping step, the drying is carried out in stages, which includes at least two temperature stages, with 80° C. and 100° C. as the dividing line between the two temperature stages, first heating and drying at less than or equal to 80° C., and then heating and drying at greater than or equal to 100° C.; The process of the pressure processing step is as follows: the alloy rod obtained by the blanking is subjected to recrystallization annealing, and then forged into a tungsten rod with a diameter of 2.5 to 4.0 mm through a multi-pass continuous rotary forging device; the tungsten rod is drawn through drawing dies of different specifications to obtain a tungsten alloy wire of the required diameter; The tungsten alloy wire needs to be annealed when it is drawn to a diameter of 0.3 to 0.5 mm, and the annealing temperature is 1300 to 1800°C. After annealing, the tungsten alloy wire is cooled in an oxygen environment. The annealed and cooled wire is drawn through wire drawing dies of different specifications, and the drawing process is repeated multiple times to draw the wire to the required diameter. During the pressure working, the alloy rod obtained by the blanking is heated to 2000-2600° C. for recrystallization annealing.

5. The method for preparing the alloy wire according to claim 4, wherein: The staged drying includes a first drying stage and a second drying stage. The temperature of the first drying stage is 50-70°C, and the temperature of the second drying stage is 100-140°C.

6. Use of the tungsten alloy wire according to any one of claims 1 to 3 in the fields of material cutting, cable, screen printing, rope or textile.

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