A production process for oxidation-resistant doped tungsten bars

Abstract

The invention discloses a production process of an anti-oxidation doped tungsten bar. The anti-oxidation doped tungsten bar is prepared by hydration reaction of aluminum nitrate and urea on the surface of an acid-washed tungsten bar. In the high-temperature process of the anti-oxidation doped tungsten bar, a modified additive is high-temperature cracked and carbonized, and a polysiloxane structure is cracked to produce silicon dioxide, which reacts with sodium carbonate to produce sodium silicate. At the same time, a multi-hole carbon layer is formed inside the tungsten bar, and the carbon layer is doped with cobalt, sulfur and boron elements, which can inhibit the growth of tungsten grains, refine the tungsten grains, and reduce the infiltration of oxygen. Then, hydrofluoric acid is treated to remove the generated sodium silicate, so that concave holes are generated on the surface of the tungsten bar. The acid-washed tungsten bar is immersed in a mixed solution of aluminum nitrate, urea and deionized water, so that the surface of the tungsten bar is covered with a water film containing aluminum ions and hydroxide ions. Then, under high-temperature conditions, an oxide film is formed on the surface of the tungsten bar to further improve the anti-oxidation effect of the tungsten bar.

Description

Technical Field

[0001] The invention relates to the technical field of tungsten bar preparation, and in particular to a production process of an oxidation-resistant doped tungsten bar. Background Art

[0002] Tungsten and tungsten alloys have been widely used in cutting-edge science, defense industry and civil industry due to their high melting point, high density, high strength, excellent wear resistance, small thermal expansion coefficient, good electrical and thermal conductivity. The main application areas are cemented carbide, electrode materials, cathode materials for electron tubes, aircraft counterweights and shock-absorbing materials, defense shells, etc., and shielding materials for X-ray protection in the medical industry. After being processed into wire, tungsten metal has high melting point and boiling point, low vapor pressure, slow evaporation rate increase with temperature, low expansion coefficient, close to the thermal expansion coefficient of glass, good airtightness when sealed with glass, and important features for electric vacuum and electric light source. It is widely used in lighting, gas discharge light source and cathode of electron tube, but its easy oxidation property seriously limits its application range in harsh environments. Summary of the invention

[0003] The purpose of the present invention is to provide a production process for oxidation-resistant doped tungsten bars, so as to solve the problem that the tungsten bars are prone to oxidation after long-term use, which affects the use effect.

[0004] The purpose of the present invention can be achieved through the following technical solutions:

[0005] A production process of an oxidation-resistant doped tungsten bar comprises the following steps:

[0006] Step A1: adding ammonium paratungstate into a reduction furnace, reacting for 15-20 minutes at a hydrogen flow rate of 300-500 L / h and a temperature of 450-460° C. to obtain blue tungsten oxide, mixing blue tungsten oxide, modified dopant, sodium carbonate and DMF, introducing nitrogen protection, ultrasonically treating for 1-1.5 hours at a frequency of 20-30 kHz and a temperature of 20-25° C., heating to 160-170° C., removing DMF to obtain a mixture, and cold pressing the mixture at a pressure of 200-250 MPa to obtain a pretreated tungsten bar;

[0007] Step A2: adding the pretreated tungsten bar into a reduction furnace, at a temperature of 550-600°C and a hydrogen flow rate of 3.5-4L / h, high temperature treatment for 10-15min, heating to 610-660°C, high temperature treatment for 10-15min, heating to 710-760°C, high temperature treatment for 10-15min, heating to 770-810°C, high temperature treatment for 10-15min, heating to 1100-1125°C, at a hydrogen flow rate of 2000L / h, heat preservation treatment for 1-1.5h, to obtain a modified tungsten bar;

[0008] Step A3: Wash the modified tungsten bar with hydrofluoric acid and dry it to obtain an acid-washed tungsten bar, mix aluminum nitrate, urea and deionized water, stir for 1-1.5 hours at a speed of 120-150r / min and a temperature of 80-85°C, immerse the acid-washed tungsten bar therein, ultrasonically treat it for 2-3 hours at a frequency of 30-40kHz, take it out and place it at a temperature of 200-210°C, and keep it warm for 20-25 hours to obtain an antioxidant doped tungsten bar.

[0009] Furthermore, the amount ratio of the blue tungsten oxide, modified dopant, sodium carbonate and DMF described in step A1 is 1250g:3g:2g:30mL.

[0010] Furthermore, the dosage ratio of aluminum nitrate, urea and deionized water in step A3 is 5.3 mmol:6 mmol:20 mL.

[0011] Further, the modified dopant is prepared by the following steps:

[0012] Step B1: octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, tetramethylammonium hydroxide, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and dimethyl sulfoxide are uniformly mixed, nitrogen is introduced for protection, and the reaction is carried out for 3-5 hours at a speed of 120-150 r / min and a temperature of 90-95° C. to obtain a diamine-terminated polysiloxane;

[0013] Step B2: Mix diamine-terminated polysiloxane, 3,5-dihydroxybenzaldehyde and dimethyl sulfoxide evenly, react for 3-5 hours at a speed of 120-150 r / min and a temperature of 70-80° C. to obtain modified polysiloxane; mix 1,4-phenylenediboric acid, methyl methacrylate and tetrahydrofuran evenly, stir and add magnesium sulfate at a speed of 120-150 r / min and a temperature of 20-25° C., and react for 20-25 hours to obtain a modifier;

[0014] Step B3: The modified polysiloxane, the modifier, chloroplatinic acid and DMF are mixed evenly, and the reaction is carried out for 8-10 hours at a rotation speed of 150-200 r / min and a temperature of 50-60°C to obtain a modified ligand; the modified ligand, phloroglucinol, cobalt nitrate hexahydrate, ammonia water, formaldehyde and DMF are mixed, and the reaction is carried out for 15-20 hours at a rotation speed of 200-300 r / min and a temperature of 30-40°C. The supernatant is removed by centrifugation, and the substrate is washed to neutrality to obtain a modified additive.

[0015] Furthermore, the molar ratio of octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, tetramethylammonium hydroxide and 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane in step B1 is 2.2:0.2:3:2.

[0016] Furthermore, the molar ratio of the diamine-terminated polysiloxane and 3,5-dihydroxybenzaldehyde in step B2 is 1:2, and the molar ratio of 1,4-phenylenediboric acid, glyceryl methacrylate and magnesium sulfate is 1:2:2.1.

[0017] Furthermore, the molar ratio of Si-H on the modified polysiloxane described in step B3 to the modifier is 2:1, the amount of chloroplatinic acid used is 1.5‰ of the mass of the modifier, and the amount ratio of the modified ligand, phloroglucinol, cobalt nitrate hexahydrate, ammonia water, formaldehyde and DMF is 1.5mmol:3mmol:6mmol:6mL:2.8mL:20mL.

[0018] The beneficial effects of the present invention are as follows: an antioxidant doped tungsten bar prepared by the present invention is prepared by using ammonium paratungstate as a raw material and reducing it with hydrogen at low temperature to obtain blue tungsten oxide, mixing the blue tungsten oxide, a modified dopant and sodium carbonate and cold pressing them to obtain a pretreated tungsten bar, reducing the pretreated tungsten bar with hydrogen at high temperature to obtain a modified tungsten bar, washing the modified tungsten bar with hydrofluoric acid and drying it to obtain a pickled tungsten bar, and hydrating aluminum nitrate and urea on the surface of the pickled tungsten bar to obtain an antioxidant doped tungsten bar.

[0019] The modified dopant is prepared by ring-opening octamethylcyclotetrasiloxane and tetramethylcyclotetrasiloxane as raw materials, and then polymerizing with 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane to obtain diamine-terminated polysiloxane. The diamine-terminated polysiloxane is reacted with 3,5-dihydroxybenzaldehyde to make the amino group on the diamine-terminated polysiloxane react with the aldehyde group on the 3,5-dihydroxybenzaldehyde to obtain a modified polysiloxane. 1,4-phenylenediboronic acid and methyl methacrylate are reacted with each other to obtain a modified polysiloxane. The esters of oil are reacted to make the boric acid group on 1,4-phenylenediboronic acid and the hydroxyl group on methacrylate glycerol be grafted to prepare a modifier, the modified polysiloxane and the modifier are reacted to make the Si-H bond on the modified polysiloxane and the double bond on the modifier be grafted to prepare a modified ligand, the modified ligand, pyroglycol and cobalt nitrate hexahydrate are reacted to make the pyroglycol and pyroglycol on the modified ligand coordinate with cobalt ions to form a metal organic framework to prepare a modified additive.

[0020] During the high-temperature process, the modified additive of the antioxidant doped tungsten bar will be cracked and carbonized at high temperature, and the polysiloxane structure therein will be cracked to produce silicon dioxide, which will then react with sodium carbonate to produce sodium silicate. At the same time, a multi-porous carbon layer will be formed inside the tungsten bar, and the internal layer is doped with cobalt, sulfur and boron elements, which can inhibit the growth of tungsten grains, refine the tungsten grains, and reduce the infiltration of oxygen. Then, through hydrofluoric acid treatment, hydrofluoric acid can remove the produced sodium silicate, so that concave holes are generated on the surface of the tungsten bar. The pickled tungsten bar is immersed in a mixture of aluminum nitrate, urea and deionized water, so that the surface of the tungsten bar is covered with a water film containing aluminum ions and hydroxide ions. Then, under high temperature conditions, an oxide film is formed on the surface of the tungsten bar, which can further enhance the antioxidant effect of the tungsten bar. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0022] Figure 1 It is an electron microscope picture of the modified additive in the present invention.

[0023] Figure 2 This is an electron microscope image of the surface of the modified tungsten bar in the present invention.

[0024] Figure 3 It is the XRD analysis diagram of the modified additive in the present invention. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in 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. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example 1

[0026] A production process of an oxidation-resistant doped tungsten bar comprises the following steps:

[0027] Step A1: adding ammonium paratungstate into a reduction furnace, reacting for 15 minutes at a hydrogen flow rate of 300 L / h and a temperature of 450° C. to obtain blue tungsten oxide, mixing blue tungsten oxide, modified dopant, sodium carbonate and DMF, introducing nitrogen protection, ultrasonically treating for 1 hour at a frequency of 20 kHz and a temperature of 20° C., heating to 160° C., removing DMF to obtain a mixture, and cold pressing the mixture at a pressure of 200 MPa to obtain a pretreated tungsten bar;

[0028] Step A2: adding the pretreated tungsten bar into a reduction furnace, at a temperature of 550°C and a hydrogen flow rate of 3.5 L / h, high temperature treatment for 10 min, heating to 610°C, high temperature treatment for 10 min, heating to 710°C, high temperature treatment for 10 min, heating to 770°C, high temperature treatment for 10 min, heating to 1100°C, at a hydrogen flow rate of 2000 L / h, heat preservation treatment for 1 h, to obtain a modified tungsten bar;

[0029] Step A3: Wash the modified tungsten bar with hydrofluoric acid and dry it to obtain an acid-washed tungsten bar. Mix aluminum nitrate, urea and deionized water, stir for 1 hour at a speed of 120r / min and a temperature of 80°C, soak the acid-washed tungsten bar therein, ultrasonically treat it for 2-3 hours at a frequency of 30kHz, take it out and place it at a temperature of 200°C, and keep it warm for 20 hours to obtain an antioxidant doped tungsten bar.

[0030] The amount ratio of the blue tungsten oxide, modified dopant, sodium carbonate and DMF described in step A1 is 1250g:3g:2g:30mL.

[0031] The dosage ratio of aluminum nitrate, urea and deionized water in step A3 is 5.3 mmol:6 mmol:20 mL.

[0032] The modified dopant is prepared by the following steps:

[0033] Step B1: octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, tetramethylammonium hydroxide, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and dimethyl sulfoxide are uniformly mixed, nitrogen is introduced for protection, and the reaction is carried out at a speed of 120 r / min and a temperature of 90° C. for 3 hours to obtain a diamine-terminated polysiloxane;

[0034] Step B2: Evenly mix diamine-terminated polysiloxane, 3,5-dihydroxybenzaldehyde and dimethyl sulfoxide, and react for 3 hours at a speed of 120 r / min and a temperature of 70° C. to obtain a modified polysiloxane; evenly mix 1,4-phenylenediboric acid, methyl methacrylate and tetrahydrofuran, and stir and add magnesium sulfate at a speed of 120 r / min and a temperature of 20° C. to react for 20 hours to obtain a modifier;

[0035] Step B3: The modified polysiloxane, the modifier, chloroplatinic acid and DMF are mixed evenly, and the reaction is carried out at a speed of 150 r / min and a temperature of 50°C for 8 hours to obtain a modified ligand; the modified ligand, phloroglucinol, cobalt nitrate hexahydrate, ammonia water, formaldehyde and DMF are mixed, and the reaction is carried out at a speed of 200 r / min and a temperature of 30°C for 15 hours, the supernatant is removed by centrifugation, and the substrate is washed to neutrality to obtain a modified additive.

[0036] The molar ratio of octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, tetramethylammonium hydroxide and 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane in step B1 is 2.2:0.2:3:2.

[0037] The molar ratio of the diamine-terminated polysiloxane to 3,5-dihydroxybenzaldehyde in step B2 is 1:2, and the molar ratio of 1,4-phenylenediboric acid, glyceryl methacrylate and magnesium sulfate is 1:2:2.1.

[0038] The molar ratio of Si-H on the modified polysiloxane described in step B3 to the modifier is 2:1, the amount of chloroplatinic acid used is 1.5‰ of the mass of the modifier, and the amount ratio of the modified ligand, phloroglucinol, cobalt nitrate hexahydrate, ammonia water, formaldehyde and DMF is 1.5mmol:3mmol:6mmol:6mL:2.8mL:20mL. Example 2

[0039] A production process of an oxidation-resistant doped tungsten bar comprises the following steps:

[0040] Step A1: adding ammonium paratungstate into a reduction furnace, reacting for 15 minutes at a hydrogen flow rate of 400 L / h and a temperature of 455° C. to obtain blue tungsten oxide, mixing blue tungsten oxide, modified dopant, sodium carbonate and DMF, introducing nitrogen protection, ultrasonically treating for 1.5 hours at a frequency of 25 kHz and a temperature of 25° C., heating to 165° C., removing DMF to obtain a mixture, and cold pressing the mixture at a pressure of 225 MPa to obtain a pretreated tungsten bar;

[0041] Step A2: adding the pretreated tungsten bar into a reduction furnace, at a temperature of 580°C and a hydrogen flow rate of 4 L / h, high temperature treatment for 15 min, heating to 635°C, high temperature treatment for 10 min, heating to 730°C, high temperature treatment for 15 min, heating to 790°C, high temperature treatment for 10 min, heating to 1120°C, at a hydrogen flow rate of 2000 L / h, heat preservation treatment for 1.5 h, to obtain a modified tungsten bar;

[0042] Step A3: Wash the modified tungsten bar with hydrofluoric acid and dry it to obtain an acid-washed tungsten bar. Mix aluminum nitrate, urea and deionized water, stir for 1 hour at a speed of 120 r / min and a temperature of 85°C, soak the acid-washed tungsten bar therein, ultrasonically treat it for 3 hours at a frequency of 35 kHz, take it out and place it at a temperature of 205°C, and keep it warm for 25 hours to obtain an antioxidant doped tungsten bar.

[0043] The amount ratio of the blue tungsten oxide, modified dopant, sodium carbonate and DMF described in step A1 is 1250g:3g:2g:30mL.

[0044] The dosage ratio of aluminum nitrate, urea and deionized water in step A3 is 5.3 mmol:6 mmol:20 mL.

[0045] The modified dopant is prepared by the following steps:

[0046] Step B1: octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, tetramethylammonium hydroxide, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and dimethyl sulfoxide are uniformly mixed, nitrogen is introduced for protection, and the reaction is carried out at a speed of 150 r / min and a temperature of 90° C. for 4 hours to obtain a diamine-terminated polysiloxane;

[0047] Step B2: Evenly mix diamine-terminated polysiloxane, 3,5-dihydroxybenzaldehyde and dimethyl sulfoxide, and react for 4 hours at a speed of 150 r / min and a temperature of 75° C. to obtain a modified polysiloxane; evenly mix 1,4-phenylenediboric acid, methyl methacrylate and tetrahydrofuran, and stir and add magnesium sulfate at a speed of 120 r / min and a temperature of 25° C. to react for 20 hours to obtain a modifier;

[0048] Step B3: The modified polysiloxane, the modifier, chloroplatinic acid and DMF are mixed evenly, and the reaction is carried out at a speed of 150 r / min and a temperature of 55°C for 9 hours to obtain a modified ligand; the modified ligand, phloroglucinol, cobalt nitrate hexahydrate, ammonia water, formaldehyde and DMF are mixed, and the reaction is carried out at a speed of 200 r / min and a temperature of 35°C for 20 hours, the supernatant is removed by centrifugation, and the substrate is washed to neutrality to obtain a modified additive.

[0049] The molar ratio of octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, tetramethylammonium hydroxide and 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane in step B1 is 2.2:0.2:3:2.

[0050] The molar ratio of the diamine-terminated polysiloxane to 3,5-dihydroxybenzaldehyde in step B2 is 1:2, and the molar ratio of 1,4-phenylenediboric acid, glyceryl methacrylate and magnesium sulfate is 1:2:2.1.

[0051] The molar ratio of Si-H on the modified polysiloxane described in step B3 to the modifier is 2:1, the amount of chloroplatinic acid used is 1.5‰ of the mass of the modifier, and the amount ratio of the modified ligand, phloroglucinol, cobalt nitrate hexahydrate, ammonia water, formaldehyde and DMF is 1.5mmol:3mmol:6mmol:6mL:2.8mL:20mL. Example 3

[0052] A production process of an oxidation-resistant doped tungsten bar comprises the following steps:

[0053] Step A1: adding ammonium paratungstate into a reduction furnace, reacting for 20 minutes at a hydrogen flow rate of 500 L / h and a temperature of 460° C. to obtain blue tungsten oxide, mixing blue tungsten oxide, modified dopant, sodium carbonate and DMF, introducing nitrogen protection, ultrasonically treating for 1.5 hours at a frequency of 30 kHz and a temperature of 25° C., heating to 170° C., removing DMF to obtain a mixture, and cold pressing the mixture at a pressure of 250 MPa to obtain a pretreated tungsten bar;

[0054] Step A2: adding the pretreated tungsten bar into a reduction furnace, at a temperature of 600° C. and a hydrogen flow rate of 4 L / h, high temperature treatment for 15 min, heating to 660° C., high temperature treatment for 15 min, heating to 760° C., high temperature treatment for 15 min, heating to 810° C., high temperature treatment for 15 min, heating to 1125° C., at a hydrogen flow rate of 2000 L / h, heat preservation treatment for 1.5 h, to obtain a modified tungsten bar;

[0055] Step A3: Wash the modified tungsten bar with hydrofluoric acid and dry it to obtain an acid-washed tungsten bar. Mix aluminum nitrate, urea and deionized water, stir for 1.5 hours at a speed of 150 r / min and a temperature of 85°C, soak the acid-washed tungsten bar therein, ultrasonically treat it for 3 hours at a frequency of 40 kHz, take it out and place it at a temperature of 210°C, and keep it warm for 25 hours to obtain an antioxidant doped tungsten bar.

[0056] The amount ratio of the blue tungsten oxide, modified dopant, sodium carbonate and DMF described in step A1 is 1250g:3g:2g:30mL.

[0057] The dosage ratio of aluminum nitrate, urea and deionized water in step A3 is 5.3 mmol:6 mmol:20 mL.

[0058] The modified dopant is prepared by the following steps:

[0059] Step B1: octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, tetramethylammonium hydroxide, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and dimethyl sulfoxide are uniformly mixed, nitrogen is introduced for protection, and the reaction is carried out at a speed of 120-150 r / min and a temperature of 95° C. for 5 hours to obtain a diamine-terminated polysiloxane;

[0060] Step B2: Evenly mix diamine-terminated polysiloxane, 3,5-dihydroxybenzaldehyde and dimethyl sulfoxide, and react for 5 hours at a speed of 150 r / min and a temperature of 80° C. to obtain a modified polysiloxane; evenly mix 1,4-phenylenediboric acid, methyl methacrylate and tetrahydrofuran, and stir and add magnesium sulfate at a speed of 150 r / min and a temperature of 25° C. to react for 25 hours to obtain a modifier;

[0061] Step B3: The modified polysiloxane, the modifier, chloroplatinic acid and DMF are mixed evenly, and the reaction is carried out at a speed of 200 r / min and a temperature of 60°C for 10 hours to obtain a modified ligand; the modified ligand, phloroglucinol, cobalt nitrate hexahydrate, ammonia water, formaldehyde and DMF are mixed, and the reaction is carried out at a speed of 300 r / min and a temperature of 40°C for 20 hours, the supernatant is removed by centrifugation, and the substrate is washed to neutrality to obtain a modified additive.

[0062] The molar ratio of octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, tetramethylammonium hydroxide and 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane in step B1 is 2.2:0.2:3:2.

[0063] The molar ratio of the diamine-terminated polysiloxane to 3,5-dihydroxybenzaldehyde in step B2 is 1:2, and the molar ratio of 1,4-phenylenediboric acid, glyceryl methacrylate and magnesium sulfate is 1:2:2.1.

[0064] The molar ratio of Si-H on the modified polysiloxane described in step B3 to the modifier is 2:1, the amount of chloroplatinic acid used is 1.5‰ of the mass of the modifier, and the amount ratio of the modified ligand, phloroglucinol, cobalt nitrate hexahydrate, ammonia water, formaldehyde and DMF is 1.5mmol:3mmol:6mmol:6mL:2.8mL:20mL.

[0065] Comparative Example 1

[0066] Compared with Example 1, this comparative example uses modified tungsten bars instead of anti-oxidation doped tungsten bars, and the remaining steps are the same.

[0067] Comparative Example 2

[0068] Compared with Example 1, no modifier was added in this comparative example, and the remaining steps were the same.

[0069] Comparative Example 3

[0070] Compared with Example 1, no modified ligand was added in this comparative example, and the remaining steps were the same.

[0071] Comparative Example 4

[0072] Compared with Example 1, this comparative example uses cobalt chloride instead of the modified dopant, and the other steps are the same.

[0073] The tungsten bars prepared in Examples 1-3 and Comparative Examples 1-4 were placed on a balance to measure their mass. The tungsten bars were then placed in a pure oxygen environment at 800° C. for 10 hours, and the amount of oxidation increase was measured. The test results are shown in the following table.

[0074] Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Oxidation increase mg 0.13 0.11 0.09 0.37 0.18 0.35 0.25

[0075] It can be seen from the above table that the present invention has a good antioxidant effect.

[0076] The above contents are merely examples and explanations of the concept of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A production process for oxidation-resistant doped tungsten bars, characterized by: The specific steps include: Step A1: adding ammonium paratungstate into a reduction furnace, introducing hydrogen, reacting to obtain blue tungsten oxide, mixing blue tungsten oxide, modified dopant, sodium carbonate and DMF, introducing nitrogen for protection, ultrasonically treating, heating to remove DMF, obtaining a mixture, and cold pressing the mixture to obtain a pretreated tungsten bar; Step A2: adding the pretreated tungsten bar into a reduction furnace, introducing hydrogen, and subjecting the tungsten bar to high temperature treatment to obtain a modified tungsten bar; Step A3: washing the modified tungsten bar with hydrofluoric acid and drying it to obtain an acid-washed tungsten bar, and then immersing the acid-washed tungsten bar in aluminum nitrate, urea and deionized water, ultrasonically treating the tungsten bar, taking it out and keeping it at high temperature to obtain an anti-oxidation doped tungsten bar; The modified dopant is prepared by the following steps: Step B1: octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, tetramethylammonium hydroxide, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and dimethyl sulfoxide are uniformly mixed, nitrogen is introduced for protection, and a reaction is carried out to obtain a diamine-terminated polysiloxane; Step B2: Mix diamine-terminated polysiloxane, 3,5-dihydroxybenzaldehyde and dimethyl sulfoxide to obtain modified polysiloxane, mix 1,4-phenylenediboric acid, methyl methacrylate and tetrahydrofuran, stir and add magnesium sulfate to react to obtain a modifier; Step B3: The modified polysiloxane, the modifier, chloroplatinic acid and DMF are mixed and reacted to obtain a modified ligand, the modified ligand, phloroglucinol, cobalt nitrate hexahydrate, ammonia water, formaldehyde and DMF are mixed and reacted, the supernatant is removed by centrifugation, and the substrate is washed to neutrality to obtain a modified dopant.

2. The production process of an oxidation-resistant doped tungsten bar according to claim 1, characterized in that: The amount ratio of the blue tungsten oxide, modified dopant, sodium carbonate and DMF described in step A1 is 1250g:3g:2g:30mL.

3. The production process of an oxidation-resistant doped tungsten bar according to claim 1, characterized in that: The dosage ratio of aluminum nitrate, urea and deionized water in step A3 is 5.3 mmol:6 mmol:20 mL.

4. The production process of an oxidation-resistant doped tungsten bar according to claim 1, characterized in that: The molar ratio of octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, tetramethylammonium hydroxide and 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane in step B1 is 2.2:0.2:3:

2.

5. The production process of the oxidation-resistant doped tungsten bar according to claim 1, characterized in that: The molar ratio of the diamine-terminated polysiloxane to 3,5-dihydroxybenzaldehyde in step B2 is 1:2, and the molar ratio of 1,4-phenylenediboric acid, glyceryl methacrylate and magnesium sulfate is 1:2:2.

1.

6. The production process of the oxidation-resistant doped tungsten bar according to claim 1, characterized in that: The molar ratio of Si-H on the modified polysiloxane and the modifier in step B3 is 2:1, and the usage ratio of the modified ligand, phloroglucinol, cobalt nitrate hexahydrate, ammonia water, formaldehyde and DMF is 1.5mmol:3mmol:6mmol:6mL:2.8mL:20mL.

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