Tungsten alloy wire, method for manufacturing the same and use thereof

Abstract

The application relates to the technical field of tungsten alloy materials, in particular to a tungsten alloy wire and a preparation method and application thereof, wherein the tungsten alloy comprises tungsten, cerium, cobalt and oxygen; the content of cerium in the tungsten alloy is 0.4-1.0 wt%; the content of cobalt is 40-500 ppm; and the content of oxygen is 0.07-0.25 wt%; the diameter of the tungsten alloy wire is less than or equal to 100 mu m; and the tensile strength of the tungsten alloy wire is greater than or equal to 4600 MPa. The tungsten alloy wire with high strength is obtained by doping cerium and cobalt with specific proportions in a tungsten matrix, so as to meet the demand of increasingly fine processing.

Description

TECHNICAL FIELD

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

[0002] In the application of high-hardness materials such as semiconductor materials sapphire, silicon carbide, silicon wafer, magnetic material cutting, high-precision instruments and high-temperature furnace traction cables or ropes, materials with high strength and high hardness are needed for processing. However, most high-strength metal wires are limited by wire diameter and tensile strength. For example, the tensile strength of existing high-carbon steel wires is generally less than 4500 MPa, and the diameter is greater than 50 μm. Therefore, it is necessary to find finer wires with higher strength to meet the needs of industrial development.

[0003] Tungsten is a metal with high melting point, high strength and excellent anti-creep performance. Tungsten-based alloys are widely used in national defense, military, aerospace, aviation, automotive, medical, electronic and other fields. In order to improve the comprehensive performance of tungsten alloy, some people propose to realize it by doping rare earth oxides in tungsten matrix. For example, Chinese patent document CN113234980B discloses an alloy wire and a preparation method and application thereof. The tungsten alloy contains tungsten and cerium oxide, and the content of cerium oxide is 0.1wt%-1.5wt%. When the wire diameter of the wire is 60 μm, the tensile strength is 4300-5200 MPa, and when the wire diameter of the wire is 40 μm, the tensile strength is 4900-5900 MPa. In the background of increasing demand for processing, it is still necessary to further refine the wire diameter of the wire and improve the tensile strength of the wire. SUMMARY

[0004] To solve the problem of improving the tensile strength of the existing tungsten alloy wire mentioned in the background art, the present application provides a tungsten alloy wire, which comprises tungsten, cerium, cobalt and oxygen. The content of cerium in the tungsten alloy is 0.4-1.0wt%, the content of cobalt is 40-500ppm, and the content of oxygen is 0.07-0.25wt%. The wire diameter of the tungsten alloy wire is ≤100 μm, and the tensile strength of the tungsten alloy wire is ≥4600 MPa.

[0005] Further, the wire diameter of the tungsten alloy wire is ≤60 μm.

[0006] The elastic limit strength of the tungsten alloy wire is ≥3000 MPa.

[0007] Further, when the wire diameter of the tungsten alloy wire is >50 μm and ≤60 μm, the tensile strength of the wire is ≥5200 MPa.

[0008] When the wire diameter of the tungsten alloy wire is >30 μm and ≤40 μm, the tensile strength of the wire is ≥6000 MPa.

[0009] The tungsten alloy wire has a diameter of 20-30 microns, and the tensile strength of the wire is greater than or equal to 6300 MPa.

[0010] Further, the tungsten alloy contains 0.6-0.8 wt% of cerium, 100-300 ppm of cobalt and 0.12-0.19 wt% of oxygen, the tungsten alloy wire has a diameter of less than or equal to 100 microns, and the tensile strength of the tungsten alloy wire is greater than or equal to 5200 MPa.

[0011] The application also provides a preparation method of the tungsten alloy wire, which comprises doping, reduction, powdering, pressing, sintering, cogging and pressure processing.

[0012] Further, the doping comprises the following steps:

[0013] The blue tungsten powder is uniformly dispersed in deionized water to obtain a blue tungsten suspension, the cerium nitrate powder and the cobalt nitrate powder are uniformly dispersed in an alkaline solution with a pH greater than 11 to form a first suspension, the first suspension is sprayed into the blue tungsten suspension, and drying is performed after the spraying is completed to obtain doped blue tungsten powder; the fine particles are directly and uniformly doped into the blue tungsten powder by preparing a compound suspension containing cerium and cobalt elements, the fine particles are used as heterogeneous crystal nuclei to jointly crystallize and precipitate with tungsten particles, the tungsten alloy powder prepared by the method has more uniform dispersion, the dispersion particles prepared by the method have a wider selection range, and the tungsten material prepared by the method has more stable and reliable performance.

[0014] Further, the blue tungsten powder is prepared by the following method: ammonium paratungstate is fed into a reduction furnace, and reduction is performed at 400-600°C under the protection of hydrogen and nitrogen to obtain 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 content is greater than 80%.

[0015] The blue tungsten powder is prepared by using hydrogen-nitrogen mixed gas as a reduction protection medium, and the performance of the discharged blue tungsten powder is controlled by the thickness of the material layer, the hydrogen flow rate and the flow direction. The oxygen index of the blue tungsten is 2.85±0.05, and the proportion of the ammonium tungsten bronze phase in the blue tungsten is greater than 80%. The blue tungsten has coarse particles and many surface cracks, which is beneficial to the entry of the rare earth solution and improves the doping effectiveness, so as to improve the uniformity of the cobalt element in the tungsten wire and improve the comprehensive mechanical properties and processing performance of the tungsten wire.

[0016] Further, the drying comprises at least two temperature stages, and 80°C is used as a dividing line. The drying is first performed at a temperature lower than 80°C, and then performed at a temperature higher than 80°C.

[0017] Further, the drying comprises a first drying stage and a second drying stage, the temperature of the first drying stage is 60-70 DEG C, and the temperature of the second drying stage is 90-120 DEG C.

[0018] The drying adopts a phased drying mode of first low-temperature (lower than 80 DEG C) drying and then high-temperature (higher than 80 DEG C) drying, so that the cerium nitrate and cobalt nitrate particles are slowly precipitated, and the nucleation number is large; and then the large number of cerium nitrate and cobalt nitrate particles cannot be combined and grown, so that the particle size can be greatly refined through the drying mode. By adjusting the doping drying temperature to control the nucleation and crystallization speed of the cerium nitrate and cobalt nitrate, the cerium nitrate and cobalt nitrate crystals on the doped blue tungsten particles are more fine and uniform, and the strengthening effect is better.

[0019] Further, the reducing and powdering comprises reducing the doped blue tungsten powder into alloy powder with an average Fisher particle size of 1.0-4.0 μm.

[0020] Further, the pressure processing is that the alloy rod obtained through the breaking down is subjected to recrystallization annealing, and then is forged to a tungsten rod with a diameter of 2.5-4.0 mm through a multi-pass continuous rotary forging equipment, and the tungsten rod is subjected to rough drawing processing through different specifications of drawing dies to obtain a tungsten alloy rough wire with a diameter of 0.3-0.5 mm.

[0021] Further, in the pressure processing, the alloy rod obtained through the breaking down is heated to 2000-2600 DEG C through a medium / high frequency induction coil for recrystallization annealing.

[0022] Further, the tungsten alloy wire needs to be subjected to annealing treatment when being drawn to a diameter of 0.3-0.5 mm, the annealing temperature is 1300-1800 DEG C, and the tungsten alloy wire is cooled in an oxygen environment after annealing.

[0023] The wire after annealing and cooling is subjected to drawing processing through different specifications of drawing dies, and is repeatedly drawn to a required wire diameter.

[0024] The application further provides an application of the tungsten alloy wire in the fields of material cutting, cable, rope or textile.

[0025] Compared with the prior art, the tungsten alloy wire, the preparation method and the application thereof have the following beneficial effects:

[0026] 1. The wire diameter of the tungsten alloy wire is 100 μm or below, and the tensile strength is greater than or equal to 4600 MPa.

[0027] 2. The wire diameter of the tungsten alloy wire is 60 μm or below, the elastic limit strength of the wire is greater than or equal to 3000 MPa, and the tensile strength of the wire is greater than or equal to 5200 MPa. DETAILED DESCRIPTION

[0028] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below. Obviously, the described embodiments are only some, but not all of the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of the present application.

[0029] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below. Obviously, the described embodiments are only some, but not all of the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of the present application.

[0030] The present application provides a tungsten alloy wire, the tungsten alloy comprising tungsten, cerium, cobalt and oxygen, the content of cerium in the tungsten alloy being 0.4-1.0 wt%, the content of cobalt being 40-500 ppm, the content of oxygen being 0.07-0.25 wt%, the balance being tungsten and inevitable impurities;

[0031] The diameter of the tungsten alloy wire is 100 μm or less, for example, the diameter of the wire is 100 μm, 80 μm, even 60 μm, 40 μm, 25 μm and 20 μm and 10 μm, etc. The diameter of the tungsten alloy wire can be uniform, or not completely uniform, and can also contain a few percentage, for example, 1%, etc. difference according to the position.

[0032] In particular, the diameter of the tungsten alloy wire can be 60 μm or less, so that the tungsten alloy wire has softness, and is easy to bend sufficiently, thus the tungsten alloy wire can be easily wound.

[0033] The tensile strength of the tungsten alloy wire is ≥4600 MPa, for example, 4800 MPa, 5000 MPa, 5500 MPa, etc.

[0034] In particular, when the diameter of the tungsten alloy wire is >50 μm and ≤60 μm, the tensile strength of the wire is ≥5200 MPa;

[0035] When the diameter of the tungsten alloy wire is >30 μm and ≤50 μm, the tensile strength of the wire is ≥6000 MPa;

[0036] When the diameter of the tungsten alloy wire is ≥20 μm and ≤30 μm, the tensile strength of the wire is ≥6300 MPa.

[0037] The elastic limit strength of the tungsten alloy wire is ≥3000 MPa, such as 3200 MPa, 3500 MPa, 4000 MPa, etc.

[0038] Preferably, the content of cerium in the tungsten alloy is 0.6-0.8 wt%, the content of cobalt is 100-300 ppm, and the content of oxygen is 0.12-0.19 wt%; the diameter of the tungsten alloy wire is ≤100 μm, and the tensile strength of the tungsten alloy wire is ≥5200 MPa.

[0039] The application provides a preparation method of a tungsten alloy wire.

[0040] The steps of the preparation method include doping, reduction powdering, pressing, sintering, blooming and pressure processing, etc.

[0041] The doping includes the following steps:

[0042] The ammonium paratungstate is fed into a reduction furnace, and reduction is performed at 400-600 ℃ under the protection of hydrogen and nitrogen to obtain blue tungsten powder, wherein the thickness of the ammonium paratungstate powder layer is <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 content is >80%.

[0043] The blue tungsten powder is uniformly dispersed in deionized water to obtain a blue tungsten suspension, cerium nitrate powder and cobalt nitrate powder are uniformly dispersed in an alkaline solution with a pH >11 to form a first suspension, and the first suspension is sprayed into the blue tungsten suspension, and drying is performed after the spraying is completed to obtain doped blue tungsten powder.

[0044] The drying includes at least two temperature stages, and the two temperature stages are divided by 80 ℃, and the drying is first performed at a temperature lower than 80 ℃, and then performed at a temperature higher than 80 ℃.

[0045] Preferably, the drying includes a first drying stage and a second drying stage, the temperature of the first drying stage is 60-70 ℃, and the temperature of the second drying stage is 90-120 ℃.

[0046] Reduction powdering: the doped blue tungsten powder is reduced in a four-temperature-zone reduction furnace into alloy powder with an average Fisher particle size of 1.0-4.0 μm.

[0047] Powder pressing: the powder with an average Fisher particle size of 1.0-4.0 μm is pressed into a compact with a single weight of 1.5-5.0 kg by isostatic pressing at a pressure of 160-260 MPa, and the compact is pre-sintered in a hydrogen atmosphere, and the temperature of the pre-sintering is preferably 1200-1400 ℃, so as to increase the strength of the compact.

[0048] sintering, preferably at a temperature of 1800-2400°C and for a time of 5-15 hours, to obtain a sintered billet with a density of 17.5-18.5 g / cm 3 ;

[0049] blooming: using a multi-roller mill to continuously roll the sintered billet with a diameter of 15-25 mm at a heating temperature of 1600-1700°C to obtain an alloy rod with a diameter of 8.0-12.0 mm;

[0050] pressure processing: recrystallization annealing the alloy rod obtained by the blooming, and then forging the alloy rod by a multi-pass continuous rotary swaging device to a tungsten rod with a diameter of 2.5-4.0 mm, and then rough drawing the tungsten rod by different specifications of drawing dies to obtain a tungsten alloy rough wire with a diameter of 0.3-0.5 mm;

[0051] Preferably, in the pressure processing, the alloy rod obtained by the blooming is heated to 2000-2600°C by a medium / high frequency induction coil for recrystallization annealing.

[0052] The tungsten alloy wire needs to be annealed when drawn to a diameter of 0.3-0.5 mm, and the annealing temperature is 1300-1800°C. After annealing, the tungsten alloy wire is cooled in an oxygen environment.

[0053] The wire after annealing and cooling is drawn by different specifications of drawing dies, and repeatedly drawn to the required wire diameter.

[0054] Then, the prepared alloy wire can be subjected to a low-temperature stress relief annealing process at a temperature of 1000°C or below, so as to homogenize the stress distribution and improve the straightness of the alloy wire. The process can be carried out in a heating furnace or other devices, and specifically, the alloy wire can also be subjected to low-temperature stress relief annealing under hydrogen protection.

[0055] Further, the drawn wire can be subjected to electrolytic polishing and cleaning, so that the surface of the wire becomes smooth. The electrolytic polishing process is carried out, for example, by immersing the alloy wire and a carbon rod or other opposite electrode in an electrolyte, and passing electricity between the alloy wire and the opposite electrode.

[0056] Example 1

[0057] A tungsten alloy wire, the material element composition of which comprises: cerium 0.4 wt%, cobalt 500 ppm, oxygen 0.091 wt%, and the balance being tungsten and unavoidable impurities. The preparation steps are as follows:

[0058] Step 1, doping: ammonium paratungstate powder is reduced by hydrogen through a 400℃, 450℃, 500℃, 560℃ reverse hydrogen continuous reduction furnace, the ammonium paratungstate powder layer thickness is 8mm, the hydrogen flow is 30L / min, the nitrogen flow is 140L / min, to obtain blue tungsten powder, the oxygen index is 2.87, the ammonium tungsten bronze phase composition is 82%;

[0059] The blue tungsten powder is uniformly dispersed in deionized water to obtain a blue tungsten suspension, wherein the volume ratio of blue tungsten powder to deionized water is 1:15; cerium nitrate powder and cobalt nitrate powder are uniformly dispersed in an alkaline solution with a pH of 12 to form a first suspension, and then the first suspension is sprayed into the blue tungsten suspension through a vacuum pipeline, and after the spraying is completed, drying is performed to obtain doped blue tungsten powder;

[0060] The drying includes a first drying stage and a second drying stage, the temperature of the first drying stage is 65℃, and the temperature of the second drying stage is 100℃;

[0061] Step 2, reduction powder: the doped blue tungsten powder obtained in step 1 is reduced in a four-temperature-zone reduction furnace to an alloy powder with an average Fisher particle size of 1.0-4.0μm;

[0062] Step 3, powder pressing: the alloy powder obtained in step 2 is pressed into a green compact with a single weight of 3.0kg by isostatic pressing at a pressure of 200MPa, and the green compact is pre-sintered at 1300℃ in a hydrogen atmosphere to increase the strength of the green compact;

[0063] Step 4, high-temperature sintering: the green compact obtained in step 3 is high-temperature sintered at 2000℃ for 10 hours to obtain a sintered bar with a density of 18.10g / cm 3 ;

[0064] Step 5, breaking down: the sintered bar with a diameter of 23.0mm is broken down into an alloy rod with a diameter of 8.0mm by continuous rolling at a heating temperature of 1650℃ using a multi-roller rolling mill;

[0065] Step 6, pressure processing: the alloy rod obtained by breaking down is heated to 2400℃ by a middle / high frequency induction coil for recrystallization annealing, and then is forged by a multi-pass continuous rotary swaging equipment to a tungsten rod with a diameter of 4.0mm, and the tungsten rod is processed by rough drawing through different specifications of drawing dies to obtain a tungsten alloy rough wire with a diameter of 0.5mm;

[0066] The tungsten alloy wire needs to be annealed when drawn to a diameter of 0.5mm, the annealing temperature is 1500℃, and the tungsten alloy wire is cooled in an oxygen environment after annealing;

[0067] The wire after annealing and cooling is drawn by different specifications of drawing dies, and repeated multiple times to draw to the required wire diameter.

[0068] Further, annealing is performed on the tungsten wire to eliminate residual stress caused by plastic deformation, so that multi-pass drawing can be smoothly performed.

[0069] Example 2

[0070] A tungsten alloy wire, whose material element composition includes: cerium 0.6wt%, cobalt 40ppm, oxygen 0.137wt%, and the balance is tungsten and inevitable impurities. The preparation steps are as follows:

[0071] Step 1, doping: ammonium paratungstate powder is reduced by hydrogen through a 400℃, 450℃, 500℃, 560℃ reverse hydrogen continuous reduction furnace, the ammonium paratungstate powder layer thickness is 9mm, the hydrogen flow is 20L / min, the nitrogen flow is 160L / min, to obtain blue tungsten powder, the oxygen index is 2.86, and the ammonium tungsten bronze phase composition is 83%;

[0072] The blue tungsten powder is uniformly dispersed in deionized water to obtain a blue tungsten suspension, wherein the volume ratio of blue tungsten powder to deionized water is 1:15; the cerium nitrate powder and the cobalt nitrate powder are uniformly dispersed in an alkaline solution with a pH of 12 to form a first suspension, and then the first suspension is sprayed into the blue tungsten suspension through a vacuum pipeline, and after the spraying is completed, drying is performed to obtain doped blue tungsten powder;

[0073] The drying includes a first drying stage and a second drying stage, the temperature of the first drying stage is 60℃, and the temperature of the second drying stage is 120℃;

[0074] Step 2, reduction powdering: the doped blue tungsten powder obtained in step 1 is reduced in a four-temperature-zone reduction furnace to an alloy powder with an average Fisher particle size of 1.0-4.0μm;

[0075] Step 3, powder pressing: the alloy powder obtained in step 2 is pressed into a single weight of 1.5kg by isostatic pressing at a pressure of 160MPa, and the green compact is pre-sintered at 1200℃ in a hydrogen atmosphere to increase the strength of the green compact;

[0076] Step 4, high-temperature sintering: the green compact obtained in step 3 is high-temperature sintered at 1800℃ for 5 hours to obtain a sintered bar with a density of 18.5g / cm 3 ;

[0077] Step 5, breaking down: the sintered bar with a diameter of 15.0mm is broken down into an alloy rod with a diameter of 9.0mm by continuous rolling at a heating temperature of 1600℃ using a multi-roller rolling mill;

[0078] Step 6, pressure processing: the alloy rod obtained by the cogging is heated to 2000℃ by a middle / high frequency induction coil for recrystallization annealing, and then is forged to a tungsten rod with a diameter of 4.0mm by a multi-pass continuous swaging equipment, the tungsten rod is processed by rough drawing through different specifications of drawing dies to obtain a tungsten alloy rough wire with a diameter of 0.4mm;

[0079] The tungsten alloy wire needs to be annealed when being drawn to a diameter of 0.4mm, the annealing temperature is 1300℃, and the tungsten alloy wire is cooled in an oxygen environment after annealing;

[0080] The wire after annealing and cooling is drawn by different specifications of drawing dies, and is repeatedly drawn to the required wire diameter.

[0081] In addition, the tungsten wire is annealed to eliminate the residual stress caused by plastic deformation, so that the multi-pass drawing process can be smoothly implemented.

[0082] Example 3

[0083] A tungsten alloy wire, the material element composition of which comprises: cerium 0.6wt%, cobalt 200ppm, oxygen 0.137wt%, and the balance is tungsten and unavoidable impurities. The preparation steps are as follows:

[0084] Step 1, doping: ammonium paratungstate powder is reduced by hydrogen at 400℃, 450℃, 500℃, and 560℃ in a reverse hydrogen continuous reduction furnace, the thickness of the ammonium paratungstate powder layer is 9mm, the hydrogen flow is 40L / min, and the nitrogen flow is 80L / min, to obtain blue tungsten powder, the oxygen index of which is 2.9, and the ammonium tungsten bronze phase content is 83%;

[0085] The 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; the cerium nitrate powder and the cobalt nitrate powder are uniformly dispersed in an alkaline solution with a pH of 12 to form a first suspension, and then the first suspension is sprayed into the blue tungsten suspension through a vacuum pipeline, and after the spraying is completed, drying is performed to obtain doped blue tungsten powder;

[0086] The drying includes a first drying stage and a second drying stage, the temperature of the first drying stage is 70℃, and the temperature of the second drying stage is 90℃;

[0087] Step 2, reduction powdering: the doped blue tungsten powder obtained in step 1 is reduced in a four-temperature-zone reduction furnace to an alloy powder with an average Fisher particle size of 1.0-4.0μm;

[0088] Step 3, powder pressing: the alloy powder obtained in step 2 is pressed into a compact with a single weight of 5.0 kg by isostatic pressing at a pressure of 260 MPa, and the compact is pre-sintered at 1400℃ in a hydrogen atmosphere to increase the strength of the compact;

[0089] Step 4, high-temperature sintering: the compact obtained in step 3 is high-temperature sintered at 2400℃ for 15 hours to obtain a sintered bar with a density of 17.5 g / cm 3 ;

[0090] Step 5, breaking down: the sintered bar with a diameter of 25.0 mm is broken down into a tungsten rod with a diameter of 12.0 mm by continuous rolling using a multi-roller rolling mill at a heating temperature of 1700℃;

[0091] Step 6, pressure processing: the tungsten rod obtained by breaking down is recrystallized annealed by heating to 2600℃ using a medium / high frequency induction coil, and then is forged to a tungsten rod with a diameter of 4.0 mm by a multi-pass continuous swaging equipment, and the tungsten rod is processed by rough drawing through different specifications of drawing dies to obtain a tungsten alloy rough wire with a diameter of 0.3 mm;

[0092] The tungsten alloy wire needs to be annealed when drawn to a diameter of 0.3 mm, and the annealing temperature is 1800℃, and the tungsten alloy wire is cooled in an oxygen environment after annealing;

[0093] The wire after annealing and cooling is drawn by different specifications of drawing dies, and is repeatedly drawn to the required wire diameter.

[0094] In addition, the tungsten wire is annealed to eliminate the residual stress caused by plastic deformation, so that the multi-pass drawing process can be smoothly implemented.

[0095] Example 4

[0096] A tungsten alloy wire, the material element composition of which comprises: cerium 0.75wt%, cobalt 200ppm, oxygen 0.171wt%, and the balance is tungsten and unavoidable impurities. The preparation steps are the same as those of example 1.

[0097] Example 5

[0098] A tungsten alloy wire, the material element composition of which comprises: cerium 0.8wt%, cobalt 300ppm, oxygen 0.183wt%, and the balance is tungsten and unavoidable impurities. The preparation steps are the same as those of example 1.

[0099] Example 6

[0100] A tungsten alloy wire, the material element composition of which comprises: cerium 1.0wt%, cobalt 100ppm, oxygen 0.229wt%, and the balance is tungsten and unavoidable impurities. The preparation steps are the same as those of example 1.

[0101] Comparative Example 1.1

[0102] A tungsten alloy wire having a material elemental composition comprising cerium 0.6 wt%, oxygen 0.137 wt%, and the balance being tungsten and unavoidable impurities. The preparation steps are the same as Example 3 except that no cobalt nitrate powder is added to the blue tungsten suspension.

[0103] Comparative Example 1.2

[0104] A tungsten alloy wire having a material elemental composition comprising cerium 0.75 wt%, oxygen 0.171 wt%, and the balance being tungsten and unavoidable impurities. The preparation steps are the same as Example 1 except that no cobalt nitrate powder is added to the blue tungsten suspension.

[0105] Comparative Example 1.3

[0106] A tungsten alloy wire having a material elemental composition comprising cerium 1.0 wt%, oxygen 0.229 wt%, and the balance being tungsten and unavoidable impurities. The preparation steps are the same as Example 1 except that no cobalt nitrate powder is added to the blue tungsten suspension.

[0107] Comparative Example 1.4

[0108] A tungsten alloy wire having a material elemental composition comprising yttrium 1.0 wt%, cobalt 100 ppm, oxygen 0.3 wt%, and the balance being tungsten and unavoidable impurities. The preparation steps are the same as Example 1 except that cerium nitrate is replaced with yttrium nitrate in Step 1.

[0109] Comparative Example 1.5

[0110] A tungsten alloy wire having a material elemental composition comprising cerium 1.0 wt%, iron 100 ppm, oxygen 0.229 wt%, and the balance being tungsten and unavoidable impurities. The preparation steps are the same as Example 1 except that cobalt nitrate is replaced with iron nitrate in Step 1.

[0111] Comparative Example 1.6

[0112] A tungsten alloy wire having a material elemental composition comprising cerium 1.0 wt%, nickel 100 ppm, oxygen 0.229 wt%, and the balance being tungsten and unavoidable impurities. The preparation steps are the same as Example 1 except that cobalt nitrate is replaced with nickel nitrate in Step 1.

[0113] Comparative Example 1.7

[0114] A tungsten alloy wire having a material elemental composition comprising cerium 1.1 wt%, cobalt 100 ppm, oxygen 0.253 wt%, and the balance being tungsten and unavoidable impurities. The preparation steps are the same as Example 1.

[0115] Comparative Example 1.8

[0116] A tungsten alloy wire, the material element composition of which comprises: cerium 1.0 wt%, cobalt 510 ppm, oxygen 0.229 wt%, the balance being tungsten and unavoidable impurities. The preparation steps are the same as those of Example 1.

[0117] Comparative Example 2.1

[0118] The material element composition is the same as that of Example 1, and the difference between the comparative example and Example 1 is that:

[0119] In Step 1, the cerium nitrate powder and the cobalt nitrate powder are dissolved in deionized water, and then added to the blue tungsten suspension for sufficient stirring at a stirring speed of 40 r / min, and the doped blue tungsten powder is obtained by drying;

[0120] The remaining steps are the same as those of Example 1.

[0121] Comparative Example 2.2

[0122] The material element composition is the same as that of Example 1, and the difference between the comparative example and Example 1 is that:

[0123] In Step 1, the temperature of the first drying stage is 90°C, and the temperature of the second drying stage is 130°C;

[0124] The remaining steps are the same as those of Example 1.

[0125] Comparative Example 2.3

[0126] The material element composition is the same as that of Example 1, and the difference between the comparative example and Example 1 is that:

[0127] In Step 6, the tungsten alloy wire after annealing is cooled in an air environment;

[0128] The remaining steps are the same as those of Example 1.

[0129] It should be noted that the specific parameters or some commonly used reagents in the above examples are specific embodiments or preferred embodiments under the concept of the present application, but not a limitation thereof; those skilled in the art can make adaptive adjustments within the concept and protection scope of the present application.

[0130] Performance test

[0131] The different specifications of the wire obtained in the examples and comparative examples are tested for tensile strength and elastic limit strength by the following method.

[0132] The test method is as follows: a standard tensile testing machine is used to clamp a tungsten wire with a length of 200 mm, one end is loaded at a constant speed to obtain the tensile strength data and the elastic limit strength;

[0133] The tensile strength is calculated by the following formula (1):

[0134] σ = F / S …… (1)

[0135] Wherein, F is the breaking force, N; S is the original cross-sectional area, mm;

[0136] The test evaluation results are shown in Table 1.

[0137] Table 1

[0138]

[0139]

[0140] Wherein: '' indicates that it cannot be processed to this specification, and there is no relevant data.

[0141] From the performance test results in Table 1, it can be seen that the tungsten alloy wire provided by the application has a tensile strength of 4600 MPa or more below 100 μm by doping cerium and cobalt in the tungsten matrix, and cobalt has a dispersion solid solution strengthening effect therein, and the addition of cobalt helps to further refine the tungsten alloy wire, and as the wire diameter decreases, the tensile strength increases, and when the wire diameter is 25 μm, the tensile strength can reach 6300 MPa or more; and the strength of the tungsten alloy wire without adding cobalt is significantly lower than that of the tungsten-cerium alloy wire with cobalt when further refined to a specification below 100 μm.

[0142] Therefore, by using the alloy wire provided by the application, due to the addition of cerium and cobalt elements in a specific ratio, an alloy wire with better performance is obtained, and under the optimization of further process, an alloy wire with finer specification, higher strength and better toughness can be mass-produced.

[0143] Therefore, the alloy wire provided by the application or the alloy wire prepared by the preparation method provided by the application can be used in the cutting processing field of conventional tungsten wire, such as sawing wire, metal mesh manufacturing by weaving the wire into warp and weft, etc.

[0144] Wherein, the sawing wire can be used for cutting various materials, such as silicon wafer, magnetic material, semiconductor material and other hard surface materials, and the semiconductor material includes sapphire, silicon carbide and other materials for cutting, or cooperates with related cutting devices to cut off, based on its excellent performance in cutting wire application, it can effectively improve the cutting quality and cutting efficiency, and the metal mesh can be used for silk screen printing, probe for inspection, or wire of catheter, etc.

[0145] It should be noted that the alloy wire provided by the present application can be used as a bus in the field of cutting, and particles such as diamonds can be electroplated or brazed thereon for cutting processing of hard surface materials including third-generation semiconductor materials such as silicon wafers, sapphire, silicon carbide, and magnetic materials.

[0146] Based on the fact that screen printing is widely used in the manufacture of printed circuit boards, thick film integrated circuits, solar cells, resistors, capacitors, piezoelectric elements, photosensitive elements, thermosensitive elements, liquid crystal display elements, etc., the metal mesh formed by the alloy wire provided by the present application can also be used for screen printing to replace stainless steel wires, such as replacing screen meshes with a size of 18 μm or less.

[0147] Furthermore, the alloy wire provided by the present application has high tensile strength, elastic limit strength, and push-pull toughness, good electrical conductivity and mechanical properties, and can be applied to the application of alloy wires in the field of medical / industrial precision instrument cables and ropes, such as the application of cables / ropes on various mechanical equipment, which can provide the highest strength and the longest service life, such as in minimally invasive surgical instruments or articulated systems, which can withstand high load and bending load

[0148] In the single crystal, polycrystalline silicon furnace lifting system, with the increase of the hoisting weight of the single crystal, polycrystalline silicon furnace, the outer diameter of the steel wire rope used in the single crystal silicon furnace is increased from 1.8 mm to 4.5 mm, but under the premise of cutting off the load of 30% or less of the steel wire, in order to improve the purity and service life of single crystal silicon, and to implant "magnetic field" into the single crystal, polycrystalline silicon furnace, the traditional process uses steel wire rope, but the steel wire rope cannot be applied to the magnetic field, which will cause the crystal direction of the finished single crystal rod to be not parallel, and the Fe-rich and high C content of the steel wire rope will easily cause the single crystal silicon to exceed the standard of main impurities, which seriously affects the requirement of high purity; and with the continuous increase of the quality of single crystal rod, the tension and service life of the rope in the single crystal, polycrystalline silicon furnace at 1500℃ are also increasing.

[0149] Therefore, the alloy wire provided by the present application can well meet the technical requirements of high strength, high tension, non-magnetic, high temperature resistance, and excellent verticality of the "lifting system" rope, so that it can be applied to smelting and casting, single crystal furnace and other smelting industries, such as high temperature furnace traction rope, etc.

[0150] 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 as a material for making micro mechanical wire for modern surgical robots.

[0151] In addition, the alloy wire can be used to drive the movement of human arms, elbows and wrists, and the movement of the surgeon's bone muscles is driven by the tungsten alloy wire instead of the surgeon's own body as in the past, so that the robot can reduce the burden of the surgeon and make the surgeon not feel tired and tired after performing multiple operations.

[0152] Moreover, as the load borne by the wire rope in the application of medical robots and medical devices is increasing, its structure is continuously optimized and improved. The commonly used 1x7, 7x7 and 7x19 structures have been replaced by more precise and complex twisted wire ropes (such as 7x37, 19x19 and 19x37). Not only the tensile strength is improved on the basis of the previous structure, but also the high modulus and excellent flexibility are increased, which can meet the more stringent application requirements of surgical instruments. More importantly, the wire rope with a diameter of half a millimeter and a 19x37 structure needs to use a filament with a diameter of only 0.0005 inches = 12.7 microns. Such fineness is almost invisible to the naked eye.

[0153] In addition, the alloy wire provided by the application has the characteristics of lightness, high strength, high toughness and the like, and can also be applied to the technical field of textiles, such as cut-resistant protective gloves, protective clothing and the like. The alloy wire has great advantages when used in cut-resistant safety protective products. The common specifications used by the existing process to directly weave tungsten wire and yarn into gloves are 18.5 microns, 30 microns and 40 microns. The alloy wire provided by the application can be processed to a finer specification, and the thinnest can reach 3 microns, so that the product has more excellent softness and is lighter and thinner. While improving the protection level, it is more comfortable and flexible to wear, and is suitable for various labor safety protection occasions. The strength of the high-strength thin tungsten wire is more than twice that of stainless steel wire. Excellent design can increase the cut-resistant level by at least 2 levels or more, so that the level evaluation reaches the high protection level of A6-A9 of the American standard and F of the European standard.

[0154] The alloy wire provided by the application can meet the corresponding requirements in terms of diameter, tensile strength and toughness. Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the application, but not to limit them; although the application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the application.

Claims

1. A method for preparing tungsten alloy wire, characterized in that: This includes doping, reduction powdering, pressing, sintering, blanking, and pressure processing; The doping includes the following steps: Blue tungsten powder is uniformly dispersed in deionized water to obtain a blue tungsten suspension. Cerium nitrate powder and cobalt nitrate powder are uniformly dispersed in an alkaline solution with pH > 11 to form a first suspension. The first suspension is then sprayed onto the blue tungsten suspension. After spraying, the solution is dried to obtain doped blue tungsten powder. The preparation method of the blue tungsten powder is as follows: ammonium paratungstate is fed into a reduction furnace and reduced at 400-600℃ under the protection of hydrogen and nitrogen to obtain blue tungsten powder. The thickness of the ammonium paratungstate powder layer is <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 composition is >80%. The drying process includes at least two temperature stages, with 80°C as the dividing line. The drying process is first carried out at a temperature below 80°C, and then at a temperature above 80°C. The drying process includes a first drying stage and a second drying stage, wherein the temperature of the first drying stage is 60-70°C and the temperature of the second drying stage is 90-120°C. The pressure processing is as follows: the alloy rod obtained from the billet is recrystallized and annealed, and then forged into a tungsten rod with a diameter of 2.5 to 4.0 mm by a multi-pass continuous rotary forging equipment. The tungsten rod is then rough drawn by drawing dies of different specifications to obtain tungsten alloy coarse wire with a diameter of 0.3 to 0.5 mm. During the pressure processing, the alloy rod obtained from the billet is heated to 2000-2600°C by a medium / high frequency induction coil for recrystallization annealing. The tungsten alloy wire needs to be annealed when it is drawn to a diameter of 0.3-0.5 mm at an annealing temperature of 1300-1800℃. After annealing, the tungsten alloy wire is cooled in an oxygen environment. After annealing and cooling, the wire is drawn through drawing dies of different specifications, and the drawing process is repeated multiple times to draw the wire to the required diameter. The tungsten alloy comprises tungsten, cerium, cobalt and oxygen, wherein the cerium content is 0.6 to 1.0 wt%, the cobalt content is 100 to 300 ppm and the oxygen content is 0.12 to 0.19 wt%.

2. The method for preparing tungsten alloy wire according to claim 1, characterized in that: The reduction powder preparation includes reducing the doped blue tungsten powder into alloy powder with an average Fisher particle size of 1.0 to 4.0 μm.

3. A tungsten alloy wire, prepared according to the method for preparing tungsten alloy wire according to claim 1 or 2, characterized in that: When the diameter of the tungsten alloy wire is >50μm and ≤60μm, the tensile strength of the wire is ≥5200MPa; When the diameter of the tungsten alloy wire is >30μm and ≤50μm, the tensile strength of the wire is ≥6000MPa; When the diameter of the tungsten alloy wire is ≥20μm and ≤30μm, the tensile strength of the wire is ≥6300MPa; The diameter of the tungsten alloy wire is ≤60μm; The elastic limit strength of the tungsten alloy wire is ≥3000MPa.

4. The application of the tungsten alloy wire as described in claim 3 in the fields of material cutting, cables, screen printing, ropes or textiles.

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