A rare earth zirconium hafnium alloy material, a preparation method and application thereof

Abstract

The application provides a rare earth zirconium hafnium alloy material and a preparation method and application thereof, and belongs to the technical field of non-ferrous metallurgy. The preparation method of the rare earth zirconium hafnium alloy material comprises the following steps: zirconium and rare earth metals are mixed according to mass percentage, and then first smelting is carried out to obtain a rare earth zirconium alloy rod; the rare earth zirconium alloy rod is heated by electric current as a high-temperature zone, and metal hafnium is placed in a low-temperature zone; iodine and metal hafnium are reacted in the low-temperature zone, and the obtained product diffuses to the high-temperature zone to be decomposed into metal hafnium coated on the surface of the rare earth zirconium alloy rod to obtain a hafnium-rare earth zirconium rod; and then second smelting is carried out on the hafnium-rare earth zirconium rod to obtain the rare earth zirconium hafnium alloy material. The addition of the rare earth metal reduces the average electron work function of the alloy material, improves the ion wind speed and air purification efficiency of a high-voltage electrostatic purification device, improves the processing performance of the alloy, reduces processing defects, and improves the service life.

Description

Technical Field

[0001] This invention relates to the field of non-ferrous metal metallurgy, and in particular to a rare earth zirconium-hafnium alloy material, its preparation method, and its application. Background Technology

[0002] In an electrostatic field, tungsten electrodes undergo corona discharge, generating an ion wind that sterilizes, disinfects, removes dust, and purifies the air. Tungsten has a melting point of 3410℃ and an electron work function of 4.5 eV. It exhibits strong resistance to electrostatic discharge oxidation and a long lifespan. However, its drawbacks include low ion wind velocity, high ozone production, and low purification efficiency. Hafnium has a melting point of 2230℃ and an electron work function of 3.5 eV. It also possesses good electrical and thermal conductivity. As a discharge electrode in electrostatic air purification equipment, it produces low ozone and high ion wind velocity. However, hafnium's resistance to electrostatic discharge oxidation is lower than that of tungsten. During the smelting process, hafnium is prone to gas absorption. Excessive gas impurities lead to poor processing performance and increased internal processing defects. Under high-voltage electrostatic discharge conditions, the frequency of tip discharge at defects increases, resulting in severe oxidation and ablation, which can easily cause electrode breakage. Its lifespan is far shorter than that of tungsten electrodes, limiting its application as a corona discharge electrode in high-voltage electrostatic purification. Secondly, metallic hafnium mainly comes from zircon sand, with a very low content (0.3-2%), and requires processes such as alkali fusion, extraction separation, and chlorination reduction to obtain. It is a scarce resource and expensive.

[0003] Therefore, it is of great significance to develop a rare earth zirconium-hafnium alloy material with excellent resistance to high voltage electrostatic discharge oxidation, long life, high ion wind speed, and low cost. Summary of the Invention

[0004] The purpose of this invention is to provide a rare earth zirconium-hafnium alloy material, its preparation method, and its application. The rare earth zirconium-hafnium alloy material is used in high-voltage electrostatic purification equipment, which has high ion wind speed, long life, low cost, and excellent resistance to high-voltage electrostatic discharge oxidation.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0006] This invention provides a rare earth zirconium-hafnium alloy material comprising the following components by mass percentage: zirconium 0.05-15%, rare earth metals 0.01-10%, and the balance being hafnium;

[0007] The rare earth metal is one or more of lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, yttrium, and lutetium.

[0008] This invention provides a method for preparing the rare earth zirconium-hafnium alloy material described above, comprising the following steps:

[0009] According to the required ratio, zirconium and rare earth metals are mixed and then subjected to the first melting and processing in sequence to obtain rare earth zirconium alloy rods.

[0010] The rare earth zirconium alloy rod is heated by electricity to form a high temperature zone, and iodine and metallic hafnium are reacted in a low temperature zone. The resulting hafnium tetraiodide is decomposed on the rare earth zirconium alloy rod to generate metallic hafnium, thus obtaining a hafnium-rare earth zirconium alloy rod.

[0011] The hafnium-rare earth zirconium alloy rod is subjected to a second smelting to obtain rare earth zirconium-hafnium alloy material;

[0012] The temperature of the high-temperature zone is 1000-1500℃, and the temperature of the low-temperature zone is 200-300℃.

[0013] Preferably, the first melting is carried out in a vacuum melting furnace, and the vacuum degree of the first melting is 5×10⁻⁶. -2 ~6×10 -3 pa.

[0014] Preferably, the second melting is carried out in a vacuum electron beam melting furnace, and the vacuum degree of the second melting is 9×10⁻⁶. -3 ~3×10 -3 pa; the second smelting is carried out twice.

[0015] This invention provides the application of the rare earth zirconium-hafnium alloy material described in the above technical solution or the rare earth zirconium-hafnium alloy material obtained by the preparation method described in the above technical solution in high-voltage electrostatic air purification equipment.

[0016] Preferably, the rare earth zirconium-hafnium alloy material is used as a corona discharge electrode in a high-voltage electrostatic air purification device in the form of rare earth zirconium-hafnium alloy wire.

[0017] Preferably, the diameter of the rare earth zirconium-hafnium alloy wire is 0.2-0.7 mm, the distance between the rare earth zirconium-hafnium alloy wire and the dust collection electrode in the high-voltage electrostatic air purification equipment is 30-60 mm, and the rare earth zirconium-hafnium alloy wire is connected to the positive terminal of the high-voltage electrostatic power supply in the high-voltage electrostatic air purification equipment.

[0018] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0019] 1) The rare earth zirconium-hafnium alloy material of the present invention contains one or more rare earth metals selected from lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, yttrium, and lutetium. The electron work function of rare earth metals gadolinium, terbium, yttrium, and lutetium is 3.1-3.3 eV. By adding zirconium and rare earth metals with low electron work function, the average electron work function of the alloy material is reduced, the electrode discharge efficiency is improved, the generated ion wind speed is increased, and the air purification efficiency is improved.

[0020] 2) In this invention, the addition of inexpensive rare earth metals and zirconium reduces the amount of rare and precious metal hafnium used, thereby reducing the cost of rare earth zirconium-hafnium alloy materials.

[0021] 3) Rare earth metals generally have low density, low melting point, and high vapor pressure. When rare earth alloys are smelted in high vacuum and high temperature, the volatilization loss of rare earth metals is significant, and the alloy composition is difficult to control. At the same time, because hafnium has a strong affinity for oxygen, during low vacuum smelting, metallic hafnium will absorb oxygen, leading to an increase in oxygen content, which in turn increases hardness and deteriorates processing performance. In contrast, this invention first prepares a zirconium and rare earth intermediate alloy, and then deposits metallic hafnium on the surface of the rare earth zirconium intermediate alloy. Metallic zirconium and hafnium are infinitely soluble at room temperature, playing a solid solution strengthening role and serving as an excellent intermediate alloy carrier. During smelting, the zirconium in the rare earth zirconium alloy can carry rare earth metals and rapidly fuse with metallic hafnium, significantly reducing the volatilization loss of rare earth metals during the alloy smelting process.

[0022] 4) In this invention, rare earth metals refine zirconium-hafnium grains, improve the microstructure of zirconium-hafnium metal, reduce processing defects inside the wire, significantly reduce oxidation and ablation of wires caused by high-voltage electrostatic spark discharge due to defects, and improve the service life of electrodes in high-voltage electrostatic air purification equipment. Attached Figure Description

[0023] Figure 1 The images shown are SEM test images of the gadolinium-zirconium-hafnium alloy wire described in Example 2, where a is a SEM test image with a magnification of 100 μm and b is a SEM test image with a magnification of 10 μm.

[0024] Figure 2 For comparison, the SEM test images of the 99.9% hafnium wire described in Application Example 1 are shown, where a is a SEM test image at 100 μm magnification and b is a SEM test image at 10 μm magnification.

[0025] Figure 3 The diagram below shows the structure of the high-voltage electrostatic purification equipment described in Application Example 1, where 1 is an alloy wire, 2 is an insulating frame, 3 is a dust collection plate, and 4 is an insulating frame.

[0026] Figure 4 A schematic diagram showing the whitening effect of spark discharge oxidation and ablation at the defect of the 99.9% pure metal hafnium wire described in Application Example 1;

[0027] Figure 5 This is a schematic diagram showing the whitening caused by spark discharge oxidation and ablation at the defect of the gadolinium-zirconium-hafnium alloy wire described in Example 2. Detailed Implementation

[0028] This invention provides a rare earth zirconium-hafnium alloy material comprising the following components by mass percentage: zirconium 0.05-15%, rare earth metals 0.01-10%, and the balance being hafnium;

[0029] The rare earth metal is one or more of lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, yttrium, and lutetium.

[0030] In this invention, unless otherwise specified, all raw materials required for preparation are commercially available products well known to those skilled in the art.

[0031] In this invention, the zirconium content by mass is 0.05-15%, preferably 0.05-10.1%, more preferably 1-5%, and even more preferably 1-3%.

[0032] In this invention, the mass percentage of the rare earth metal is 0.01-10%, preferably 0.1-5.2%, more preferably 0.1-1.2%, and even more preferably 0.1-0.52%.

[0033] In this invention, the rare earth metal is one or more of lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, yttrium, and lutetium, preferably yttrium and / or gadolinium.

[0034] This invention provides a method for preparing the rare earth zirconium-hafnium alloy material described above, comprising the following steps:

[0035] According to the required ratio, zirconium and rare earth metals are mixed and then subjected to the first melting and processing in sequence to obtain rare earth zirconium alloy rods.

[0036] The rare earth zirconium alloy rod is heated by electricity to form a high-temperature zone, and iodine and metallic hafnium are reacted in a low-temperature zone. The resulting hafnium tetraiodide is decomposed on the rare earth zirconium alloy rod to obtain a hafnium-rare earth zirconium alloy rod.

[0037] The hafnium-rare earth zirconium alloy rod is subjected to a second smelting to obtain rare earth zirconium-hafnium alloy material;

[0038] The temperature of the high-temperature zone is 1000-1500℃, and the temperature of the low-temperature zone is 200-300℃.

[0039] In this invention, zirconium is mixed with rare earth metals and preferably pressed into shape, followed by a first melting process. This invention does not impose any particular limitation on the pressing process; any process well-known in the art can be followed.

[0040] In this invention, the electron work function of gadolinium, terbium, yttrium, and lutetium is between 3.1 and 3.3 eV. By adding zirconium and rare earth metals with low electron work function, the resulting alloy material has a low average electron work function. As a corona discharge electrode in a high-voltage electrostatic air purification device, it generates a high ion velocity and high air purification efficiency. Furthermore, gadolinium and yttrium are abundant and inexpensive, further reducing the cost of the alloy.

[0041] In this invention, the melting point of the rare earth metal is between 1300-1650℃, which is close to the melting point of zirconium metal. When forming a rare earth zirconium master alloy, the volatilization loss is small. In addition, the degassing, impurity removal, grain refinement and strengthening effects of rare earth metal in metal materials improve the processing performance of the alloy, greatly reduce internal defects in the formed material, and extend its service life.

[0042] The present invention does not impose any particular limitation on the morphology of the hafnium, zirconium and rare earth metals, and those skilled in the art can select them according to actual needs, such as: sponge hafnium, metal hafnium shavings, metal hafnium blocks, sponge zirconium, metal zirconium shavings, metal zirconium blocks, and blocky rare earth metals; in the embodiments of the present invention, the metal hafnium is preferably in the form of nuclear-grade sponge hafnium, and the rare earth metals yttrium and gadolinium are preferably in the form of pure yttrium blocks and pure gadolinium blocks.

[0043] The present invention does not impose any particular limitation on the smelting equipment used for the zirconium and rare earth metals. Those skilled in the art can select according to actual needs, such as: vacuum induction melting furnace, vacuum suspension melting furnace or vacuum arc melting furnace; in the embodiments of the present invention, the first smelting is preferably carried out in a vacuum induction melting furnace.

[0044] In this invention, the vacuum degree of the first melting process is preferably 5 × 10⁻⁶. -2 ~6×10 -3 pa, further preferably 3×10 -2 ~8×10 -3 pa, more preferably 1×10 -2 ~8×10 -3 pa, the first smelting is preferably performed twice.

[0045] After the first melting is completed, the rare earth zirconium alloy ingot obtained by the present invention is processed into rare earth zirconium alloy rods; the present invention does not have a special limitation on the size of the rare earth zirconium alloy rods, which can be adjusted according to actual needs. In the embodiments of the present invention, the diameter of the rare earth zirconium alloy rods is preferably 6mm or 10mm.

[0046] The present invention does not specifically limit the processing method of the rare earth zirconium alloy rod. Those skilled in the art can select according to actual needs, such as at least one of forging, rolling, extrusion, stamping, turning, drawing, etc.

[0047] In this invention, hafnium metal is preferably placed around the furnace wall of a vacuum reactor, and the rare earth zirconium alloy rod is connected to a power source. The rare earth zirconium alloy rod is heated by electricity to form a high-temperature zone, while the area around the furnace wall is a low-temperature zone.

[0048] In this invention, the temperature of the high-temperature zone is 1000-1500℃, preferably 1000-1200℃, and more preferably 1200℃; the temperature of the low-temperature zone is 200-300℃, preferably 200-250℃, and more preferably 250℃.

[0049] Iodine reacts with metallic hafnium in a low-temperature region to form hafnium tetraiodide. The hafnium tetraiodide diffuses onto the high-temperature rare earth zirconium alloy rod to form metallic hafnium, which coats the surface of the rare earth zirconium alloy rod, forming a cylindrical rare earth zirconium alloy rod with the rare earth zirconium alloy rod as the core and the surface covered with metallic hafnium.

[0050] Hafnium has a melting point of 2222℃ and a density of 13.1 g / cm³. 3 When smelting rare earth hafnium alloys, hafnium has a strong affinity for oxygen, causing metallic hafnium to absorb oxygen, leading to an increase in oxygen content, which in turn increases hardness and deteriorates processing performance. Metallic hafnium smelting needs to be carried out under high temperature and high vacuum conditions. However, rare earth metals have low melting points and high vapor pressures, resulting in significant volatilization losses when smelting alloys under high temperature and high vacuum conditions. This invention solves the above technical problems by first preparing a zirconium and rare earth intermediate alloy and then depositing metallic hafnium on the surface of the rare earth zirconium intermediate alloy.

[0051] In this invention, the melting point and density of zirconium metal are close to those of rare earth metals. Zirconium metal and rare earth metals can easily form a rare earth zirconium master alloy with uniform composition. Zirconium and hafnium are elements in the same group with similar chemical properties. Zirconium metal and hafnium metal are infinitely miscible, playing a solid solution strengthening role. Zirconium metal is an excellent master alloy carrier. During smelting, zirconium in the rare earth zirconium alloy can carry rare earth metals and hafnium metal to fuse rapidly.

[0052] After obtaining the rare earth zirconium alloy rod, the present invention preferably performs surface pretreatment before performing a second melting.

[0053] The present invention does not specifically limit the method and conditions for surface pretreatment of rare earth zirconium alloy rods. Those skilled in the art can select according to actual needs, such as at least one of ultrasonic cleaning, pickling, and machining.

[0054] In this invention, the second melting is preferably carried out in a vacuum electron beam melting furnace, and the vacuum degree of the second melting is preferably 9×10⁻⁶. -3 ~3×10 -3 pa, further preferably 3×10 -3 ~5×10 -3 pa; the second smelting is preferably performed twice.

[0055] In a vacuum electron beam melting furnace, a high-energy electron beam bombards the surface of a hafnium-zirconium rare earth alloy rod, causing the metallic hafnium to melt and the rare earth zirconium alloy to melt. Due to the infinite mutual solubility of metallic zirconium and hafnium, the metallic zirconium carries the rare earth metal and hafnium into the molten pool for further mixing, forming a rare earth zirconium-hafnium alloy. This greatly reduces the volatilization loss of rare earth metal and promotes alloy homogenization.

[0056] After the second smelting, a rare earth zirconium-hafnium alloy material with uniform composition was obtained.

[0057] This invention provides the application of rare earth zirconium-hafnium alloy materials as described in the above-described technical solutions or the preparation method of rare earth zirconium-hafnium alloy materials as described in the above-described technical solutions in high-voltage electrostatic air purification equipment.

[0058] In this invention, the rare earth zirconium-hafnium alloy material is preferably used as a corona discharge electrode in a high-voltage electrostatic air purification device in the form of rare earth zirconium-hafnium alloy wire.

[0059] In this invention, the diameter of the rare earth zirconium-hafnium alloy wire is preferably 0.2-0.7 mm, more preferably 0.3-0.55 mm, and even more preferably 0.4-0.55 mm; the distance between the rare earth zirconium-hafnium alloy wire and the dust collection electrode in the high-voltage electrostatic air purification device is preferably 30-60 mm, more preferably 35-55 mm, and even more preferably 40-50 mm; the rare earth zirconium-hafnium alloy wire is connected to the positive terminal of the high-voltage electrostatic power supply in the high-voltage electrostatic air purification device.

[0060] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0061] Example 1

[0062] (1) Nuclear-grade sponge zirconium and pure yttrium blocks were mixed evenly according to the mass percentages of zirconium 1%, yttrium 0.52%, and the balance being hafnium, and then pressed into shape; the vacuum degree of the melting furnace was 1×10⁻⁶ in a vacuum induction melting furnace. -2 The yttrium-zirconium alloy ingot was obtained by melting twice at pa, and then the yttrium-zirconium alloy ingot was forged and machined into a yttrium-zirconium alloy rod with a diameter of 6mm.

[0063] (2) Place the nuclear-grade sponge hafnium around the walls of the vacuum reactor, connect the yttrium zirconium alloy rod from step (1) to the power supply, and evacuate to 5×10⁻⁶. -3Pa, close all vacuum valves to form a sealed space, then add iodine, turn on the power to heat the yttrium zirconium alloy rod, and control the temperature of the low-temperature zone of the furnace wall to be 250℃ and the temperature of the high-temperature zone formed by the yttrium zirconium alloy rod to be 1200℃. Iodine reacts with metallic hafnium to generate hafnium tetraiodide. The hafnium tetraiodide diffuses to the high-temperature yttrium zirconium alloy rod to generate metallic hafnium, which coats the surface of the yttrium zirconium alloy rod, forming a cylindrical hafnium-yttrium zirconium alloy rod with the yttrium zirconium alloy rod as the core and the surface covered with metallic hafnium.

[0064] (3) The hafnium yttrium zirconium alloy rod from step (2) was ultrasonically cleaned with pure water, dried at 85°C, and then subjected to a vacuum of 5×10⁻⁶. -3 The hafnium-yttrium-zirconium alloy was obtained by melting it twice in an electron beam melting furnace of PA.

[0065] Example 2

[0066] (1) According to the mass percentages of zirconium 3%, gadolinium 1.2%, and the balance hafnium, nuclear-grade sponge zirconium and pure gadolinium blocks are mixed evenly and pressed into shape; in a vacuum induction melting furnace, the vacuum degree of the melting furnace is 1×10 -2 The gadolinium-zirconium alloy ingot was obtained by melting twice at pa. The gadolinium-zirconium alloy ingot was then forged and machined into a gadolinium-zirconium alloy rod with a diameter of 10 mm.

[0067] (2) Place the nuclear-grade sponge hafnium around the walls of the vacuum reactor, connect the gadolinium-zirconium alloy rod from step (1) to the power supply, and evacuate to 5×10⁻⁶. -3 pa, close all vacuum valves to form a sealed space, and then add iodine; turn on the power to heat the gadolinium-zirconium alloy rod, and when the temperature of the low-temperature zone of the furnace wall is controlled at 250℃ and the temperature of the high-temperature zone formed by the gadolinium-zirconium alloy rod is controlled at 1200℃, add iodine. Iodine reacts with metallic hafnium to generate hafnium tetraiodide. Hafnium tetraiodide diffuses to the high-temperature gadolinium-zirconium alloy rod to generate metallic hafnium that coats the surface of the gadolinium-zirconium alloy rod, forming a round hafnium-gadolinium alloy rod with the gadolinium-zirconium alloy rod as the core and the surface covered with metallic hafnium.

[0068] (3) After ultrasonically cleaning the surface of the hafnium-gadolinium-zirconium alloy rod in step (2) with pure water and drying it at 85°C, the rod is then subjected to a vacuum of 5×10⁻⁶. -3 The hafnium-gadolinium alloy was obtained by melting it twice in an electron beam melting furnace of pa.

[0069] Example 3

[0070] (1) According to the mass percentages of zirconium 5%, yttrium 2.9%, gadolinium 2.3%, and the balance being hafnium, nuclear-grade sponge zirconium, pure gadolinium blocks, and pure yttrium blocks are mixed evenly and pressed into shape; in a vacuum induction melting furnace, the vacuum degree of the melting furnace is 1×10 -2 Yttrium-zirconium alloy ingots were obtained by melting twice at Pa, and then the ingots were processed into yttrium-zirconium alloy rods with a diameter of 10 mm.

[0071] (2) Place nuclear-grade sponge hafnium around the walls of the vacuum reactor, connect the gadolinium-yttrium-zirconium alloy rod from step (1) to the power supply, and evacuate to a vacuum level of 5 × 10⁻⁶. -3 pa, close all vacuum valves to form a sealed space, then add iodine; turn on the power to heat the gadolinium-yttrium-zirconium alloy rod, and control the temperature of the low-temperature zone of the furnace wall to be 250℃ and the temperature of the high-temperature zone formed by the gadolinium-yttrium-zirconium alloy rod to be 1200℃. Iodine reacts with metallic hafnium to generate hafnium tetraiodide. The hafnium tetraiodide diffuses to the high-temperature gadolinium-yttrium-zirconium alloy rod to generate metallic hafnium, which coats the surface of the gadolinium-yttrium-zirconium alloy rod, forming a cylindrical hafnium-yttrium-zirconium-hafnium alloy rod with the gadolinium-yttrium-zirconium alloy rod as the core and the surface covered with metallic hafnium.

[0072] (3) After ultrasonically cleaning the surface of the yttrium-gadolinium-zirconium-hafnium alloy rod in step (2) with pure water and drying it at 85°C, the rod is then subjected to a vacuum of 5×10⁻⁶. -3 The hafnium-gadolinium-yttrium alloy was obtained by melting twice in an electron beam melting furnace of pa.

[0073] Application Example 1

[0074] The yttrium-zirconium-hafnium alloy obtained in Example 1 was processed into 0.4 mm diameter yttrium-zirconium-hafnium alloy wires, which were used as electrodes for a high-voltage electrostatic air purifier and connected to the positive terminal of a high-voltage electrostatic power supply. Four stainless steel sheets, each 50 mm wide and 250 mm long, were used as dust collection plates, parallel to each other and 50 mm apart, fixed to an insulating support. These plates were connected to the negative terminal of the high-voltage power supply. The yttrium-zirconium-hafnium alloy wire was positioned between two adjacent steel sheets, 45 mm away from the adjacent sheets, and parallel to the edges of the steel sheets. Figure 3 As shown.

[0075] Application Example 2

[0076] The only difference from Application Example 1 is that the hafnium-gadolinium-zirconium alloy obtained in Example 2 is used, while other conditions remain unchanged.

[0077] Application Example 3

[0078] The only difference from Application Example 1 is that the hafnium-gadolinium-yttrium alloy obtained in Example 3 is used, while other conditions remain unchanged.

[0079] Comparative Application Example 1

[0080] The only difference from Application Example 1 is that 99.9% pure metal hafnium wire is used as the electrode of the high-voltage electrostatic air purifier, while other conditions remain unchanged.

[0081] Comparative Application Example 2

[0082] The only difference from Application Example 1 is that tungsten wire is used as the electrode of the high-voltage electrostatic air purifier, while other conditions remain the same.

[0083] Performance testing

[0084] 1) Connect the high-voltage electrostatic purification equipment described in Application Examples 1-3 and Comparative Application Examples 1-2 to a 26kV DC voltage and test the wind speed at a distance of 30cm from the dust collection plate; place the high-voltage electrostatic purification equipment in a 1m³ test chamber, connect a 26kV DC voltage, and set the smoke concentration generated by a standard cigarette to reach 700μg / m³. 3 The PM2.5 level was tested and found to be 35 μg / m³. 3 The required time was 24 hours of continuous operation to test the service life of the wire material, i.e., the continuous operating time. The operating conditions were tested under a 26kV DC voltage condition for 24 hours. The results are shown in Table 1.

[0085] Table 1. Performance test results of Application Examples 1-3 and Comparative Application Examples 1-2.

[0086]

[0087] A comparison of the data in Table 1 shows that the rare-earth zirconium-hafnium alloy material prepared in this invention, when used as an electrode material in a high-voltage electrostatic air purifier, significantly improves ion velocity and air purification efficiency compared to 99.9% pure metallic hafnium. The 99.9% pure metallic hafnium material experienced wire breakage and shutdown of the purification equipment after 43 days of operation. (The 99.9% pure metallic hafnium material exhibits whitening due to spark discharge oxidation at defects, as seen in...) Figure 4 Rare earth zirconium hafnium alloy materials have been operating stably for over 180 days, with no obvious discharge oxidation, ablation, or whitening on the wire surface (see...). Figure 5 This significantly improves the lifespan of the electrodes.

[0088] 2) SEM tests were performed on the gadolinium-zirconium hafnium alloy wire described in Example 2 and the 99.9% pure metal hafnium wire described in Comparative Application Example 1. The results are as follows: Figure 1 and Figure 2 As shown; via Figure 1 , Figure 2 As can be seen from the comparison, the internal defects of the gadolinium-zirconium-hafnium alloy wire prepared by the preparation method provided by the present invention are greatly reduced in size and number compared with those of pure metal hafnium wire, thereby significantly improving its service life.

[0089] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a rare earth zirconium-hafnium alloy material, characterized in that, Includes the following steps: According to the required ratio, zirconium and rare earth metals are mixed and then subjected to the first smelting and processing in sequence to obtain rare earth zirconium alloy rods; The rare earth zirconium alloy rod is heated by electricity to form a high temperature zone, and iodine and metallic hafnium are reacted in a low temperature zone. The resulting hafnium tetraiodide is decomposed on the rare earth zirconium alloy rod to generate metallic hafnium, thus obtaining a hafnium-rare earth zirconium alloy rod. The hafnium-rare earth zirconium alloy rod is subjected to a second smelting to obtain rare earth zirconium-hafnium alloy material; The temperature of the high-temperature zone is 1000~1500℃, and the temperature of the low-temperature zone is 200~300℃; The rare earth zirconium-hafnium alloy material comprises the following components by mass percentage: zirconium 0.05~15%, rare earth metals 0.01~10%, and the balance being hafnium; the rare earth metals are one or more selected from lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, yttrium, and lutetium.

2. The method for preparing rare earth zirconium-hafnium alloy material according to claim 1, characterized in that, The first melting process is carried out twice in a vacuum melting furnace, with a vacuum degree of 5 × 10⁻⁶. -2 ~6×10 -3 pa.

3. The method for preparing rare earth zirconium-hafnium alloy material according to claim 2, characterized in that, The second melting is carried out in a vacuum electron beam melting furnace, and the vacuum degree of the second melting is 9×10⁻⁶. -3 ~3×10 -3 pa; the second smelting is carried out twice.

4. The application of the rare earth zirconium-hafnium alloy material prepared by the preparation method according to any one of claims 1 to 3 in high-voltage electrostatic air purification equipment.

5. The application according to claim 4, characterized in that, The rare earth zirconium-hafnium alloy material is used as a corona discharge electrode in high-voltage electrostatic air purification equipment in the form of rare earth zirconium-hafnium alloy wire.

6. The application according to claim 4 or 5, characterized in that, The diameter of the rare earth zirconium-hafnium alloy wire is 0.2~0.7mm, the distance between the rare earth zirconium-hafnium alloy wire and the dust collection electrode in the high-voltage electrostatic air purification equipment is 30~60mm, and the rare earth zirconium-hafnium alloy wire is connected to the positive terminal of the high-voltage electrostatic power supply in the high-voltage electrostatic air purification equipment.

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