Multi-stage gradient reactor and method for preparing hafnium sponge

Abstract

The present application relates to the technical field of sponge hafnium preparation, and provides a multistage gradient reaction furnace and method for preparing sponge hafnium, the reaction furnace comprising a machine body, a storage cylinder, a reaction cavity, a preliminary reaction box, a cylinder body, a centrifugal mechanism and a heat recovery module. The cylinder body adopts a multilayer composite structure of a permalloy magnetic guide layer, yttrium-zirconium lining, permanent magnet array and steel shell. The permanent magnet array forms a radial magnetic field, which suppresses the micro-turbulence of molten magnesium chloride, reduces the oxygen diffusion coefficient and reduces the migration of oxygen to the grain boundary. In a temperature environment of 800-1000 DEG C, under the synergistic effect of a low-oxygen grain boundary environment and a thermal gradient effect, hafnium grains grow to form uniformly distributed radiation state crystals. The reaction process is controlled by multistage gradient temperature control of 600-800 DEG C preliminary reaction, 800-1000 DEG C grain growth and 1000-1100 DEG C melting separation, combined with vibration acceleration reaction and centrifugal separation of by-products, to realize efficient and high-purity sponge hafnium preparation.

Description

Technical Field

[0001] The present invention relates to the technical field of hafnium sponge preparation, and in particular to a multi-stage gradient reaction furnace and a method for preparing hafnium sponge. Background Art

[0002] As an important strategic metal material, hafnium sponge is widely used in aerospace, nuclear industry, and high-end electronic devices due to its excellent high-temperature resistance, corrosion resistance, and neutron absorption properties. Currently, the main method for industrial production of hafnium sponge is metallothermal reduction, which involves a high-temperature reduction reaction between hafnium tetrachloride and magnesium metal to produce hafnium metal and magnesium chloride as a byproduct. However, the traditional production process has the following technical bottlenecks:

[0003] Traditional hafnium sponge production processes lack an effective directional guidance mechanism during grain growth. The grains tend to be disordered, resulting in uneven size distribution and poor orientation. Oxygen atoms easily diffuse into grain boundaries, increasing impurity adsorption in the product. Furthermore, microturbulence in the molten byproduct exacerbates grain boundary instability and impurity accumulation, leading to a loose structure and weakened mechanical properties in the final product, making it difficult to meet the material uniformity requirements for high-end applications. The initial reduction, grain growth, and melt separation steps are performed at the same temperature, resulting in increased impurity residues and limited separation efficiency. Lack of precise control over the temperature transition process leads to inadequate grain purification. Furthermore, the lack of or inefficiency of heat recovery systems prevents the effective capture and reuse of waste heat from high-temperature exhaust gases, increasing external energy consumption. This extensive management approach not only increases production costs but also limits the feasibility of industrial continuous production. During the separation stage, single temperature control fails to optimize the separation conditions between the molten byproduct and hafnium sponge, resulting in high residual magnesium chloride and low recovery rates. Incomplete separation also leads to impurities encapsulating the grains, compromising product purity.

[0004] The above technical defects have jointly restricted the industrial production of hafnium sponge. The present invention solves the above technical problems through the design of a multi-stage gradient reactor and method for preparing hafnium sponge, providing a new solution for the continuous production of high-quality hafnium sponge. Summary of the Invention

[0005] In order to solve the problems existing in the background technology, the present invention provides a multi-stage gradient reactor for preparing hafnium sponge, comprising:

[0006] body;

[0007] A fixing plate fixed to the top of the machine body, and a storage cylinder installed on the top of the fixing plate;

[0008] A first discharge pipe connected to the bottom of the storage cylinder, a first valve provided on the first discharge pipe; a reaction chamber installed on the left side of the top of the body, and a partition plate provided inside the reaction chamber;

[0009] A first electric push rod, a liquid pump and a collection box for driving the separation plate to rise and fall;

[0010] The vibration mechanism includes a preliminary reaction box connected to the top of the machine body by a spring, a fifth electric push rod and a pressure block for driving the vibration of the preliminary reaction box, a third electric push rod and a baffle for controlling the opening and closing of the discharge slot, a fourth electric push rod for driving the flip, a clamping block, a second drive motor, a drive gear, and a driven gear;

[0011] The moving mechanism includes a second screw driven by a first stepper motor, a movable plate slidably mounted on the second guide rod, a cylinder fixed inside the movable plate, a second discharge channel connected to the bottom of the cylinder, and a second valve provided on the second discharge channel;

[0012] From the inside out, the cylinder is sequentially equipped with a permalloy magnetic conductive layer, a yttrium zirconium liner, a permanent magnet array, and a steel shell. The permalloy magnetic conductive layer is plated on the inside of the yttrium zirconium liner through a magnetron sputtering process, focusing the magnetic field lines on the material at the center of the cylinder. The yttrium zirconium liner is provided with guide grooves, and the front and rear ends of the permanent magnet array are respectively embedded in the guide grooves of the yttrium zirconium liner and the ceramic glue. The steel shell is the outermost layer. The permanent magnet array consists of 24 iron-cobalt-vanadium-based permanent magnet alloy magnets evenly distributed along the circumference of the cylinder, with each magnet having an angular width of 12 degrees. The iron-cobalt-vanadium-based permanent magnet alloy magnets of the permanent magnet array are arranged alternately with north and south poles and fixed by ceramic glue. An insulation layer is filled between the outer steel shell and the ceramic glue, and the insulation layer is composed of a silicon nitride layer and zirconium oxide fiber felt.

[0013] The centrifugal mechanism includes a turntable driven by a third drive motor, a fixed cylinder fixed to the top of the turntable, a shielding cylinder sleeved on the outside of the fixed cylinder, a second stepping motor and a third screw for controlling the lifting and lowering of the shielding cylinder, a feeding channel and a third valve arranged on the feeding channel.

[0014] In a preferred solution, in the moving mechanism, the movable plate is connected to the second screw rod through a thread and is slidably installed on the second guide rod, and a sealing gasket and a sealing groove structure are provided between the movable plate and the partition plate.

[0015] In a preferred solution, the centrifugal mechanism further includes a third guide rod fixedly connecting the turntable and the top plate, and the shielding cylinder is slidably connected to the third guide rod.

[0016] In a preferred solution, the heat recovery module includes a heat exchanger and a return air pipe connected to the top of the reaction chamber, and the return air pipe is connected to the preliminary reaction box.

[0017] In a preferred solution, in the vibration mechanism, the cylinder is arranged inside the spring, and the vibration frequency of the pressing block driven by the fifth electric push rod is synchronized with the expansion and contraction frequency of the cylinder.

[0018] In a preferred solution, a heat-insulating layer is filled between the steel shell and the ceramic glue, and the heat-insulating layer is composed of a silicon nitride layer and a zirconium oxide fiber felt.

[0019] The present invention provides a method for preparing hafnium sponge by multi-stage gradient reaction, comprising the following steps:

[0020] S1: Load hafnium tetrachloride and magnesium metal into their respective storage cylinders, and control the raw materials to enter the preliminary reaction box;

[0021] S2: The initial reaction box is accelerated by mechanical vibration at 600-800°C, and the system completes the reduction reaction of hafnium tetrachloride to produce a mixture of hafnium and magnesium chloride;

[0022] S3: turning over the preliminary reaction box to allow the hafnium and magnesium chloride mixture to fall into the cylinder;

[0023] S4: The cylinder moves to the first reaction zone at 800-1000°C. The permanent magnet array inside the cylinder consists of 24 iron-cobalt-vanadium-based permanent magnet alloy magnets evenly distributed along the circumference of the cylinder, with N and S poles alternating, forming a radial static magnetic field. A permalloy magnetic conductive layer plated on the inner side of the yttrium-zirconium liner converges the static magnetic field lines generated by the permanent magnet array to the center of the cylinder. The static magnetic field suppresses the micro-turbulence of the molten magnesium chloride, reduces the oxygen diffusion coefficient, and reduces the migration of oxygen to the grain boundaries. At a temperature of 800-1000°C, the hafnium grains grow to form uniformly distributed radial crystals under the synergistic thermal gradient effect of the low-oxygen grain boundary environment.

[0024] S5: moving the cylinder to the second reaction zone at 1000-1100°C, allowing the hafnium sponge and molten magnesium chloride to enter the centrifugal fixed cylinder;

[0025] S6: Magnesium chloride is discharged from the fixed cylinder through centrifugal separation, and the liquid pump recovers it to the collection box. At the same time, the high-temperature exhaust gas returns to the preliminary reaction box through the heat recovery system.

[0026] Furthermore, S1 and S2 include the following specific steps:

[0027] S11: Hafnium tetrachloride and magnesium metal are loaded into storage cylinders respectively, and the screw conveying rod is driven to rotate by a first driving motor;

[0028] S12: Open the first valve to adjust the flow rate of the first discharge pipe so that hafnium tetrachloride and metallic magnesium enter the preliminary reaction box at a molar ratio of 1:2;

[0029] S21: Under the environment of 600-800℃, the fifth electric push rod drives the pressing block to press the preliminary reaction box to contract the spring, and then the spring recovers its deformation to push the preliminary reaction box to vibrate up and down;

[0030] S22: The cylinder is located inside the spring, and its expansion and contraction frequency is synchronized with the vibration frequency of the fifth electric push rod, accelerating the reaction to generate a mixture of hafnium and magnesium chloride.

[0031] Furthermore, the specific steps of S3 and S4 include:

[0032] S31: The third electric push rod controls the baffle to rise and open the discharge slot of the preliminary reaction box;

[0033] S32: The fourth electric push rod drives the card block to engage with the card slot of the preliminary reaction box;

[0034] S33: The second driving motor drives the preliminary reaction box to flip through the driving gear and the driven gear, so that the mixture falls into the cylinder;

[0035] S41: The first stepper motor drives the second screw to rotate, and the movable plate slides along the second guide rod, driving the cylinder to move to the first reaction area of ​​800-1000°C for crystal nucleus growth.

[0036] Furthermore, the specific steps of S5 and S6 include:

[0037] S51: The first electric push rod drives the partition plate to rise;

[0038] S52: The first stepper motor drives the second screw to rotate, and the movable plate slides along the second guide rod, driving the cylinder to move to the second reaction area of ​​1000-1100°C;

[0039] S53: Open the second valve and the third valve to allow the molten hafnium sponge and magnesium chloride to enter the fixed cylinder through the second discharge channel and the feed channel;

[0040] S61: The second stepper motor drives the third screw to rotate, controlling the shielding cylinder to rise and expose the liquid outlet groove of the fixed cylinder;

[0041] S62: The third driving motor drives the turntable to rotate, and the liquid magnesium chloride is discharged from the liquid outlet tank through centrifugal separation;

[0042] S63: The liquid pump recovers the liquid magnesium chloride to a collection tank;

[0043] S64: The high-temperature exhaust gas is purified and returned to the preliminary reaction box through a heat exchanger and a return air pipe for heat reuse.

[0044] The beneficial effects achieved by the present invention are:

[0045] First, the present invention designs a cylindrical structure that optimizes grain growth. The cylindrical structure integrates a multilayer composite design of a permanent magnet array, a permalloy magnetic layer, and a yttrium-zirconium lining. The permanent magnet array consists of 24 iron-cobalt-vanadium-based permanent magnet alloy magnets arranged with alternating north and south poles to form a static radial magnetic field. The permalloy magnetic layer is plated on the inner side of the lining through a magnetron sputtering process to focus the magnetic field lines on the center of the cylindrical structure. In the first reaction zone at 800-1000°C, the static magnetic field suppresses the microturbulence of molten magnesium chloride, reducing the oxygen diffusion coefficient by 40-60%, significantly reducing the migration of oxygen to the grain boundaries. The resulting low-oxygen grain boundary environment, in synergistic with the thermal gradient effect, drives the hafnium grains to grow preferentially in the radial direction, forming highly oriented radial columnar crystals. The grain orientation degree is increased to ≥85%, solving the problems of disordered grain growth and excessive oxygen content.

[0046] Second, the present invention significantly improves the preparation efficiency and product purity of hafnium sponge through multi-stage gradient temperature control and innovative structural design. In the initial reaction stage, a vibration mechanism is used to achieve mechanical vibration to accelerate the reaction process. The electric push rod drives the pressure block in conjunction with the spring and cylinder to make the initial reaction box vibrate at high frequency in an environment of 600-800°C, promoting the full mixing of hafnium tetrachloride and metallic magnesium; the zoned temperature gradient design of the moving mechanism further enhances the grain purification and melt separation. The mechanism drives the screw to slide the movable plate through a stepping motor, so that the cylinder moves precisely between the first reaction zone of 800-1000°C and the second reaction zone of 1000-1100°C. The lifting and sealing of the partition plate ensures that the temperature zones are independently controllable, optimizing the temperature transition process. After the grains are continuously purified under the action of the magnetic field in the first reaction zone, the high-temperature second reaction zone promotes the separation of molten magnesium chloride and hafnium sponge, solving the problems of excessive impurity residues and insufficient separation in traditional single-temperature zone reactions.

[0047] Third, the design of the centrifugal mechanism achieves efficient recovery of by-products. The fixed cylinder is equipped with a liftable shielding cylinder that exposes the liquid tank through the control of a stepper motor. The molten magnesium chloride is separated by density difference under the high-speed rotation of the turntable, and the liquid pump recovers it to the collection box. Combined with temperature control, it ensures that the liquid by-products are quickly discharged. Centrifugal separation reduces the phenomenon of grain wrapping, resulting in significantly improved separation efficiency and a greatly improved resource recovery rate. The heat recovery module purifies the high-temperature exhaust gas from the second reaction area through a heat exchanger and a return air pipe and returns it to the preliminary reaction box. The integrated cyclone separator and ceramic fiber filter remove impurities. The temperature buffer device stabilizes the air flow temperature to achieve energy recycling. The system's thermal utilization rate is significantly improved and external energy consumption is reduced, resulting in greatly optimized energy efficiency and enhanced continuous production stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0049] Figure 2Schematic diagram of the internal structure of the storage cylinder in the present invention;

[0050] Figure 3 It is a front view of the present invention;

[0051] Figure 4 Schematic diagram of the structure of the vibration mechanism of the present invention;

[0052] Figure 5 Schematic diagram of the structure of the opening and closing mechanism of the present invention;

[0053] Figure 6 Schematic diagram of the internal structure of the reaction chamber in the present invention;

[0054] Figure 7 Schematic diagram of the structure of the interior of the reaction chamber of the present invention from another perspective;

[0055] Figure 8 Schematic diagram of the structure of the centrifugal mechanism in the present invention;

[0056] Figure 9 Schematic diagram of the internal structure of the fixing tube and the shielding tube in the present invention;

[0057] Figure 10 It is a schematic diagram of the top view of the cylinder;

[0058] Figure 11 The present invention is a flow chart of the method for preparing hafnium sponge by multi-stage gradient reaction.

[0059] Numbers in the figure:

[0060] 1, body; 101, fixed plate; 102, storage cylinder; 103, spiral conveying rod; 104, first driving motor; 105, first discharge pipe; 106, first valve; 107, reaction cavity; 108, first electric push rod; 109, partition plate; 110, liquid pumping pump; 111, collection box; 2, vibration mechanism; 201, spring; 202, preliminary reaction box; 203, second electric push rod; 204, top cover; 205, air cylinder; 206, third electric push rod; 207, baffle; 208, support plate; 209, fourth electric push rod; 210, second driving motor; 211, driving gear; 212, driven gear; 213, clamping block; 214, fifth electric push rod; 215, pressing block; 3, opening and closing mechanism; 301, first screw rod; 302, first guide rod; 303, double-shaft motor; 304, cover; 305, heat exchanger; 306, gas return pipe; 4, moving mechanism; 401, second screw rod; 402, second guide rod; 403, first stepping motor; 404, movable plate; 405, cylinder body; 406, second discharge channel; 407, second valve; 5, centrifugal mechanism; 501, third driving motor; 502, rotating disc; 503, fixed cylinder; 504, third guide rod; 505, top plate; 506, third screw rod; 507, second stepping motor; 508, shielding cylinder; 509, feeding channel; 510, third valve; 61, steel shell; 62, ceramic glue; 63, permanent magnet array; 631, N-pole; 632, S-pole; 64, yttrium zirconium inner liner; 65, pyromagnetic layer; 66, heat insulation layer. DETAILED DESCRIPTION

[0061] The technical solutions in the present application will be described clearly and completely below in combination with the drawings in the present application. In addition, the forms of the structures described in the following embodiments are only examples, and the present application is not limited to the structures described in the following embodiments. All other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present application.

[0062] REFERENCE Figures 1-11The application provides a multistage gradient reaction furnace for preparing sponge hafnium, which comprises a body 1, a fixed plate 101 fixed on the top of the body 1, a storage cylinder 102 installed on the top end of the fixed plate 101, a first discharge pipe 105 communicated with the bottom of the storage cylinder 102, a first valve 106 arranged on the first discharge pipe 105, a reaction cavity 107 installed on the top left side of the body 1, a partition plate 109 arranged in the reaction cavity 107, a first electric push rod 108 for driving the partition plate 109 to lift, a liquid pump 110 and a collection tank 111, a vibrating mechanism 2, the vibrating mechanism 2 comprising a preliminary reaction tank 202 connected to the top of the body 1 through a spring 201, a fifth electric push rod 214 and a pressing block 215 for driving the preliminary reaction tank 202 to vibrate, a third electric push rod 206 and a baffle 207 for controlling the opening and closing of a discharge slot, a fourth electric push rod 209 for driving overturning, a clamping block 213, a second driving motor 210, a driving gear 211 and a driven gear 212, a moving mechanism 4, the moving mechanism 4 comprising a second lead screw 401 driven by a first stepping motor 403, a movable plate 404 slidingly installed on a second guide rod 402, a cylinder 405 fixed in the movable plate 404, a second discharge channel 406 communicated with the bottom of the cylinder 405 and a second valve 407 arranged on the second discharge channel 406.

[0063] The cylinder 405 is sequentially provided with a permalloy magnetic conductive layer 65, a yttrium zirconium lining 64, a permanent magnet array 63 and a steel shell 61 from inside to outside; the permalloy magnetic conductive layer 65 is plated on the inner side of the yttrium zirconium lining 64 through a magnetic control sputtering process, and focuses the magnetic field lines on the material in the center of the cylinder 405; the yttrium zirconium lining 64 is provided with a guide groove, and the front end and the rear end of the permanent magnet array 63 are respectively embedded in the guide groove of the yttrium zirconium lining 64 and the ceramic glue 62; the steel shell 61 is located at the outermost layer; the permanent magnet array 63 is uniformly distributed along the circumference of the cylinder 405 by 24 iron-cobalt-vanadium-based permanent magnet magnets, and each magnet has a size angle width of 12°; the iron-cobalt-vanadium-based permanent magnet magnets of the permanent magnet array 63 are alternately arranged in N poles 631 and S poles 632, and are fixed by the ceramic glue 62; a heat insulation layer 66 is filled between the outer steel shell 61 and the ceramic glue 62, and the heat insulation layer 66 is composed of a silicon nitride layer and a zirconium fiber felt.

[0064] The centrifugal mechanism 5 includes a turntable 502 driven by a third drive motor 501, a fixed cylinder 503 fixed to the top of the turntable 502, a shielding cylinder 508 sleeved on the outside of the fixed cylinder 503, a second stepping motor 507 and a third screw rod 506 for controlling the raising and lowering of the shielding cylinder 508, a feed channel 509 connected thereto, and a third valve 510 provided on the feed channel 509. In the movable mechanism 4, a movable plate 404 is threadedly connected to the second screw rod 401 and slidably mounted on the second guide rod 402, and a sealing gasket and sealing groove structure are provided between the movable plate 404 and the partition plate 109. The centrifugal mechanism 5 also includes a third guide rod 504 fixedly connected to the turntable 502 and the top plate 505, and a shielding cylinder 508 is slidably connected to the third guide rod 504. The heat recovery module includes a heat exchanger 305 and a return air pipe 306 connected to the top of the reaction chamber 107, and the return air pipe 306 is connected to the preliminary reaction box 202.

[0065] In the vibration mechanism 2, the cylinder 205 is located inside the spring 201, and the vibration frequency of the fifth electric push rod 214 driving the pressure block 215 is synchronized with the expansion and contraction frequency of the cylinder 205. A thermal insulation layer 66 is filled between the steel shell 61 and the ceramic glue 62. The thermal insulation layer 66 is composed of a silicon nitride layer and zirconium oxide fiber felt.

[0066] Cylinder 405, a core component of the multi-stage gradient reactor for hafnium sponge production, is used to optimize grain growth performance. Fixed within movable plate 404, it precisely moves between the first and second reaction zones via a moving mechanism 4, thereby supporting the directional growth and melt separation of grains in a high-temperature environment. Structurally, cylinder 405 is composed of multiple layers of composite materials. The innermost layer is a magnetically conductive permalloy layer, which directly contacts the reactants. By focusing the magnetic field lines at the center of the cylinder, it significantly improves the radial orientation consistency of the grains and reduces impurity adsorption. Furthermore, the magnetic conductivity of permalloy optimizes the distribution efficiency of the magnetic field, increasing grain size uniformity by 75%.

[0067] Adjacent to the outer side of the Permalloy magnetic conductive layer is the yttrium zirconium lining. This layer, as an intermediate structure, provides excellent high-temperature resistance and corrosion resistance. It can operate stably in environments above 1000 degrees Celsius, effectively isolating the molten material from contact with external metal, thereby reducing the oxygen impurity content to below 30ppm. At the same time, the yttrium zirconium lining is provided with a guide groove for installing the permanent magnet array. After the permanent magnet array is installed in the guide groove, the permanent magnet array is embedded in the ceramic glue layer on the periphery of the yttrium zirconium lining, and the other end of the magnet array is embedded in ceramic glue to ensure the sealing and durability of the overall structure.

[0068] Permanent magnets are made of iron-cobalt-vanadium-based permanent magnet alloy material, a total of 24 evenly distributed along the circumference of the cylinder, the angle width of each magnet is 12 degrees, the adjacent magnets are arranged alternately with N and S poles, forming a radial static magnetic field, the static magnetic field can suppress the micro-turbulence of molten magnesium chloride, greatly reduce the oxygen diffusion coefficient, and greatly reduce the migration of oxygen to the grain boundary.

[0069] Iron-cobalt-vanadium-based permanent magnet alloy, code 2J31, is a typical iron-cobalt-vanadium-based permanent magnet precision alloy with excellent magnetic properties, high temperature stability and processability. The composition of 2J31 is based on iron Fe, cobalt Co and vanadium V, and the typical composition ratio is: cobalt Co: about 27%-30%; vanadium V: about 1%-2%; iron Fe: balance. The Curie temperature of the alloy can reach 980-1050℃ by adding cobalt element, which can provide high temperature demagnetization resistance; vanadium element can improve the mechanical properties of the alloy through solid solution strengthening and grain refinement, and can also inhibit the grain growth at high temperature, further stabilize the magnetic properties. The iron-cobalt-vanadium-based permanent magnet alloy can still maintain its magnetism after working in a 1000℃ environment for several hours, and can partially recover after a small amount of demagnetization cooling. It is one of the few permanent magnet materials that can be used in ultra-high temperature environments. The preparation process of iron-cobalt-vanadium-based permanent magnet alloy 2J31 includes melting, vacuum induction melting to reduce the content of gas oxygen, nitrogen and impurities such as sulfur and phosphorus, and ensure uniform composition; plastic deformation, through hot rolling, cold rolling or forging processing to refine the grain and form preferred orientation; heat treatment, solid solution treatment at 1050-1150℃ temperature and water quenching to make vanadium and other elements fully solid solution and eliminate processing stress; heat preservation at 500-600℃ temperature for several hours to precipitate vanadium carbide or intermetallic compound, strengthen the alloy and stabilize the magnetic properties; magnetization in a strong magnetic field greater than 1.5 T to make the magnetic domain directional arrangement and obtain permanent magnet properties.

[0070] The yttrium zirconium liner is a ceramic material, which is a non-ferromagnetic insulator with a relative magnetic permeability close to vacuum. The static magnetic field can penetrate such materials, and a 2mm permalloy layer is added inside the yttrium zirconium liner, which is a high magnetic permeability material that forces the magnetic field lines to converge to the center area of the cylinder.

[0071] The outermost layer is a steel shell structure, which serves as a mechanical protection layer. The steel shell not only provides overall strength and stiffness to the cylinder, but also effectively dissipates high temperature heat during movement, ensuring that the remanence retention rate of the permanent magnet at 1000℃ is over 90%. In terms of position relationship, the layers of the cylinder 405 from inside to outside are permalloy magnetic conducting layer, yttrium zirconium liner, permanent magnet array, and steel shell. This layered structure ensures that the magnetic field is concentrated in the center area of the cylinder, and the synergistic effect of the silicon nitride heat insulation layer between the steel shell and the ceramic glue and the zirconium fiber felt absorbs the difference in thermal expansion, avoiding high temperature deformation.

[0072] Permalloy, a high-permeability iron-nickel alloy, is used as the permeable layer in the reactor. Its typical composition is 80% nickel and 20% iron. In the reaction furnace, it is plated on the inside of the yttrium-zirconium lining, which is used to focus the magnetic field lines on the reactant material in the center of the cylinder. Its core function is to optimize the magnetic field distribution and guide hafnium atoms along the magnetic lines of force to form a radial and uniform columnar grain, reducing impurity adsorption at the grain boundary and improving the consistency of the grain size. The permeability of Permalloy is much higher than that of ordinary metals, which can efficiently focus the magnetic field and reduce hysteresis loss. In high-temperature reactions, it can reduce eddy current effects and prevent magnetic field diffusion, ensuring that the grain growth direction is controllable. The Permalloy permeable layer is plated on the inside of the yttrium-zirconium lining through a magnetron sputtering process.

[0073] The material used for the yttrium-zirconium lining is YSZ, Yttria-Stabilized Zirconia, which has excellent high-temperature stability, low thermal conductivity, and thermal shock resistance. It is a ceramic material that stabilizes the high-temperature cubic phase structure of zirconia by doping yttria. In the reaction furnace, it serves as the intermediate layer of the cylinder 405, directly contacting the molten reactant, providing inert protection, inhibiting high-temperature corrosion and impurities, including oxygen and nitrogen penetration, and ensuring the purity of the hafnium sponge. The yttrium-zirconium lining is located outside the Permalloy permeable layer and is fixed by ceramic glue and the permanent magnet array. The sintering process is carried out in an inert atmosphere at a temperature of 1500-1600°C for 2 hours, forming a dense corrosion-resistant layer.

[0074] The permanent magnet array includes 24 iron-cobalt-vanadium-based permanent magnet alloys, evenly distributed along the circumference of the cylinder, with each angle width of 12°. The magnets are arranged alternately with N and S poles, and are fixed by ceramic glue after being installed in the guide groove of the yttrium-zirconium lining. The steel shell is the outermost structure of the cylinder 405, made of high-strength steel, mainly providing mechanical protection and thermal management support. It fixes the internal components and prevents high-temperature deformation or vibration damage. The steel shell is filled with a thermal insulation layer between the ceramic glue, providing excellent rigidity and creep resistance. During movement, the steel shell maintains the stability of the cylinder, ensuring that the remanence retention rate of the permanent magnet is >90% at 1000°C.

[0075] The thermal insulation layer is located between the steel shell and the ceramic glue, composed of a silicon nitride layer and a zirconia fiber felt, used for thermal insulation and thermal shock resistance. Its function is to reduce heat loss, balance the thermal expansion difference of different materials, and prevent structural deformation at high temperatures. In the second reaction area, the thermal insulation layer reduces external heat input, making the system's thermal utilization rate reach 75%, and avoiding the degradation of the performance of the permanent magnet.

[0076] The manufacturing process for cylinder 405 is as follows: A guide groove is created on the outside of the yttrium-zirconium liner, into which 24 iron-cobalt-vanadium-based permanent magnet alloy magnets are embedded. Each magnet has a 12° angle and is evenly distributed along the circumference of the cylinder. The magnets are arranged with alternating north and south poles, with a spacing of 2 mm to prevent magnetic interference. After embedding, the magnets are secured with ceramic adhesive, which cures at 800°C to form a stable bond. The ceramic adhesive is composed of a composite of aluminum silicate and yttrium oxide. The aluminum silicate provides high-temperature stability and bond strength, while the yttrium oxide enhances high-temperature resistance and thermal shock resistance. The yttrium oxide content is 10–30 wt% to balance temperature resistance and bond strength. The magnets are then coated with ceramic adhesive and placed on the outside of the yttrium-zirconium liner. After the adhesive cures, a steel shell is added to the outer layer. A silicon nitride thermal insulation layer and zirconium oxide fiber felt are placed between the steel shell and the ceramic adhesive to absorb thermal expansion differences, ensuring that the permanent magnets have a residual magnetic retention of >90% at 1000°C. The yttrium zirconium liner is re-sintered on the integrated structure. Sintering is performed in an inert atmosphere at a controlled temperature of 1500-1600°C for two hours to form a dense, corrosion-resistant layer. A permalloy magnetic layer is deposited on the inner side of the yttrium zirconium liner using a magnetron sputtering process. Sputtering parameters include a vacuum environment, a sputtering power of 5kW, and a deposition rate of 0.1μm / min. The permalloy layer focuses the magnetic field lines at the center of the cylinder, optimizing the radial orientation of the grains.

[0077] The present invention realizes efficient and high-purity preparation of hafnium sponge through multi-stage gradient temperature control and structural design, precise molar ratio control, vibration-accelerated reaction, temperature gradient optimization of grain growth, and heat recovery to improve efficiency. The vibration mechanism 2 realizes up and down vibration through spring 201 and cylinder 205 to accelerate the contact of reactants; the partitioned reaction module uses partition plate 109 to divide the temperature zone to enhance the purity and separation of grains; the centrifugal mechanism 5 uses density difference to realize liquid by-product recovery. The reaction process is that hafnium tetrachloride and metallic magnesium undergo a reduction reaction at high temperature to generate hafnium sponge and magnesium chloride. The reaction equation is HfCl4+2Mg→Hf+2MgCl2. Specifically comprising the following steps:

[0078] S1: Load hafnium tetrachloride and magnesium metal into their respective storage cylinders, and control the raw materials to enter the preliminary reaction box;

[0079] S2: The initial reaction box is accelerated by mechanical vibration at 600-800°C, and the system completes the reduction reaction of hafnium tetrachloride to produce a mixture of hafnium and magnesium chloride;

[0080] S3: turning over the preliminary reaction box to allow the hafnium and magnesium chloride mixture to fall into the cylinder;

[0081] S4: The cylinder moves to the first reaction zone at 800-1000°C. The permanent magnet array 63 inside the cylinder 405 consists of 24 iron-cobalt-vanadium-based permanent magnet alloy magnets evenly distributed along the circumference of the cylinder, with N poles 631 and S poles 632 arranged alternately, forming a radial static magnetic field. A permalloy conductive layer 65, deposited on the inner side of the yttrium-zirconium liner 64 by a magnetron sputtering process, converges the static magnetic field lines generated by the permanent magnet array 63 into the central area of ​​the cylinder. The static magnetic field suppresses the micro-turbulence of the molten magnesium chloride and reduces the diffusion of oxygen atoms to the grain boundaries. At a temperature of 800-1000°C, the static magnetic field greatly reduces the oxygen diffusion coefficient by suppressing the micro-turbulence of the molten magnesium chloride, significantly reducing the migration of oxygen to the grain boundaries. The resulting low-oxygen grain boundary environment, in synergistic with the thermal gradient effect, drives the preferential growth of hafnium grains in the radial direction, forming highly oriented radial columnar crystals, and increasing the grain orientation degree to ≥85%.

[0082] S5: moving the cylinder to the second reaction zone at 1000-1100°C, allowing the hafnium sponge and molten magnesium chloride to enter the centrifugal fixed cylinder;

[0083] S6: Magnesium chloride is discharged from the fixed cylinder through centrifugal separation, and the liquid pump recovers it to the collection box. At the same time, the high-temperature exhaust gas returns to the preliminary reaction box through the heat recovery system.

[0084] S1 and S2 include the following specific steps:

[0085] S11: Hafnium tetrachloride and magnesium metal are loaded into the storage cylinder 102 respectively, and the first driving motor 104 drives the screw conveying rod 103 to rotate;

[0086] S12: Open the first valve 106 to adjust the flow rate of the first discharge pipe 105 so that hafnium tetrachloride and metallic magnesium enter the preliminary reaction box 202 at a molar ratio of 1:2;

[0087] S21: Under the temperature of 600-800°C, the fifth electric push rod 214 drives the pressing block 215 to press the preliminary reaction box 202 to shrink the spring 201. Then, the spring 201 recovers its deformation and pushes the preliminary reaction box 202 to vibrate up and down.

[0088] S22: The cylinder 205 is disposed inside the spring 201, and its expansion and contraction frequency is synchronized with the vibration frequency of the fifth electric push rod 214, accelerating the reaction to generate a mixture of hafnium and magnesium chloride.

[0089] The specific steps of S3 and S4 include:

[0090] S31: The third electric push rod 206 controls the baffle 207 to rise, opening the discharge slot of the preliminary reaction box 202;

[0091] S32: The fourth electric push rod 209 drives the clamping block 213 to clamp into the clamping slot of the preliminary reaction box 202;

[0092] S33: The second driving motor 210 drives the preliminary reaction box 202 to flip through the driving gear 211 and the driven gear 212, so that the mixture falls into the cylinder 405;

[0093] S41: The first stepper motor 403 drives the second screw 401 to rotate, and the movable plate 404 slides along the second guide rod 402, driving the cylinder 405 to move to the first reaction area of ​​800-1000°C;

[0094] S42: The Permalloy magnetic conductive layer 65 focuses the static magnetic field lines generated by the permanent magnet array 63 at the center of the cylinder to form a radial static magnetic field; the static magnetic field suppresses the micro-turbulence of the molten magnesium chloride and reduces the diffusion of oxygen atoms to the grain boundaries.

[0095] The specific steps of S5 and S6 include:

[0096] S51: The first electric push rod 108 drives the partition plate 109 to rise;

[0097] S52: The first stepper motor 403 drives the second screw rod 401 to rotate, and the movable plate 404 slides along the second guide rod 402, driving the cylinder 405 to move to the second reaction area of ​​1000-1100°C;

[0098] S53: Open the second valve 407 and the third valve 510 to allow the molten hafnium sponge and magnesium chloride to enter the fixed cylinder 503 through the second discharge channel 406 and the feed channel 509;

[0099] S61: The second stepper motor 507 drives the third screw rod 506 to rotate, controlling the shielding cylinder 508 to rise and expose the liquid outlet groove of the fixed cylinder 503;

[0100] S62: The third driving motor 501 drives the turntable 502 to rotate, and the liquid magnesium chloride is discharged from the liquid outlet tank through centrifugal separation;

[0101] S63: The liquid pump 110 recovers the liquid magnesium chloride to the collection box 111;

[0102] S64: The high-temperature exhaust gas is purified and returns to the primary reaction box 202 through the heat exchanger 305 and the return gas pipe 306 for heat reuse. The specific process described by stage is as follows:

[0103] Feeding Stage: Precisely Control the Molar Ratio and Automatically Discharge the Materials. First, hafnium tetrachloride (HfCl4) and magnesium (Mg) are loaded into two separate storage cylinders 102, mounted on a fixed plate 101 at the top of the machine body 1. Quantitative feeding is achieved via a screw conveyor 103 and a first drive motor 104. The specific process is as follows: The first drive motor 104 rotates the screw conveyor 103, controlling the feed rate according to a preset speed to ensure that the HfCl4 and Mg enter the preliminary reaction chamber 202 in a strict 1:2 molar ratio. This process is achieved by opening the first valve 106 to adjust the flow rate through the first discharge pipe 105. The structure that implements this process includes the storage cylinders 102, the screw conveyor 103, and the first valve 106. The design of the screw conveyor 103 allows for continuous and stable material delivery, eliminating human error. This precise control of the molar ratio prevents incomplete reaction and the accumulation of byproducts, thereby improving product purity. An imbalance in the molar ratio can lead to an incomplete reduction reaction and impurity accumulation, which can affect subsequent grain growth. The reaction has not yet started at this stage, but feeding is a prerequisite for the reduction reaction to ensure uniform mixing of the raw materials. The structure of the feeding module is tightly integrated, and the rotation of the spiral conveying rod 103 inside the storage barrel 102 directly drives the flow of raw materials.

[0104] Initial reaction stage: Vibration-accelerated reduction reaction is carried out at a controlled temperature. The raw materials enter the initial reaction chamber 202, where a reduction reaction occurs at a temperature of 600-800°C. The initial reaction chamber 202 is mechanically vibrated by the vibration mechanism 2 to accelerate contact between the reactants. A pressing block 215 is connected to the initial reaction chamber 202. The fifth electric push rod 214 drives the pressing block 215 downward, compressing the initial reaction chamber 202 and contracting the spring 201. Subsequently, the fifth electric push rod 214 quickly returns to its original position, causing the spring 201 to recover and vibrate the initial reaction chamber 202 up and down, promoting thorough mixing of HfCl4 and Mg, triggering the reduction reaction: HfCl4 + 2Mg → Hf + 2MgCl2, and producing a solid mixture of hafnium sponge and magnesium chloride. The structure implementing this process includes the initial reaction chamber 202, spring 201, cylinder 205, fifth electric push rod 214, and pressing block 215. The vibration mechanism 2, through the coordinated action of the cylinder 205 and spring 201, generates high-frequency vibrations to prevent the reactants from agglomerating. Vibration significantly shortens reaction time. Traditional methods require extended stirring times. Mechanical vibration increases the frequency of particle collisions, boosting the reaction rate. Furthermore, temperature control between 600-800°C optimizes reaction kinetics, preventing premature melting and impurity adsorption. The reaction involves the reduction of HfCl₄, with Mg acting as a reducing agent to provide electrons, generating primary hafnium sponge particles and MgCl₂ as a byproduct. The design of the vibration mechanism 2 also includes a baffle 207 and a third electric actuator 206 for subsequent discharge control.

[0105] During the mixture transfer phase, the mixture is automatically flipped and sealed and transferred to the mobile cylinder 405. After the reaction is complete, the preliminary reaction box 202 transfers the mixture to the mobile cylinder via a flipping mechanism. This process ensures that the material seamlessly enters the next stage. The specific process is as follows: the third electric push rod 206 contracts, driving the baffle 207 upward, opening the discharge slot on the left side of the preliminary reaction box 202. Simultaneously, the fourth electric push rod 209 drives the clamping block 213 to engage the clamping slot of the preliminary reaction box 202. The second drive motor 210, via the drive gear 211 and driven gear 212, flips the preliminary reaction box 202, causing the Hf and MgCl2 mixture to fall into the cylinder. The structure that implements this process includes the fourth electric push rod 209, the clamping block 213, the second drive motor 210, the gear train, and the baffle 207. The flipping mechanism achieves smooth flipping through the precise displacement of the electric push rod and the gear transmission, preventing material spillage. Automated transfer reduces manual intervention and improves efficiency. A gasket is placed between the movable plate 404 and the partition plate 109 to prevent leakage from the high-temperature environment and maintain an inert atmosphere in the reaction chamber 107. The reaction is paused at this stage, but transfer is a critical link in the temperature gradient reaction, ensuring that the mixture enters the growth environment intact. The moving mechanism 4, driven by the first stepper motor 403, drives the second screw 401, driving the movable plate 404 and the cylinder 405 in motion, preparing for the subsequent partitioning reaction.

[0106] First Reaction Zone Stage: After the mixture enters the movable cylinder, it is moved to the first reaction zone of the reaction chamber 107 at 800-1000°C, promoting the growth and purification of hafnium sponge grains. The specific process is as follows: a first stepper motor 403 drives the second screw 401 to rotate, causing the movable plate 404 to slide along the second guide rod 402, positioning the cylinder in the first reaction zone. The first electric push rod 108 controls the rise and fall of the partition plate 109, isolating the temperature zones. The cylinder is maintained at 800-1000°C for a period of time, where the magnetic field environment enhances grain growth. The structure implementing this process includes a moving mechanism 4, comprising the second screw 401, movable plate 404, second guide rod 402, partition plate 109, and first electric push rod 108. This achieves a temperature gradient of 800-1000°C to optimize grain size and uniformity. An opening and closing mechanism 3, driven by a dual-axis motor 303, drives the first screw 301, controlling the opening and closing of the cover 304 to maintain the seal of the reaction chamber 107.

[0107] Second reaction zone stage: The cylinder moves from the first reaction zone to the second reaction zone (1000-1100°C), allowing the mixture to enter the centrifugal mechanism 5. The specific process is as follows: the first electric push rod 108 raises the partition plate 109, and the first stepper motor 403 drives the movable plate 404 to move the cylinder to the second reaction zone; then, the partition plate 109 is reset, and the temperature is raised to 1000-1100°C, allowing Hf and molten MgCl2 to react; the second valve 407 and the third valve 510 are opened, allowing the reactants to enter the feed channel 509 of the centrifugal mechanism 5 through the second discharge channel 406, and then enter the fixed cylinder 503. The structure implementing this process includes the moving mechanism 4, the partition plate 109, the valve system, the feed channel 509 of the centrifugal mechanism 5, and the fixed cylinder 503. Temperature control is achieved through the heating system of the reaction chamber 107. High-temperature melting separation of liquid MgCl2 is achieved. The melting point of MgCl2 is 714°C and the melting point of Hf is 2230°C. MgCl2 is molten at 1000-1100°C, and the density difference facilitates centrifugal separation. At this stage, the heat recovery module starts working and the high-temperature exhaust gas enters the heat exchanger 305.

[0108] Centrifugal separation and heat recovery stage: Efficiently separate by-products and recycle heat energy; in the centrifugal mechanism 5, the molten mixture is separated by centrifugal force, MgCl2 is recovered and heat recovery is achieved. The specific process is: the third drive motor 501 drives the turntable 502 and the fixed cylinder 503 to rotate for centrifugal separation; the second stepper motor 507 drives the third screw 506 to control the lifting height of the shielding cylinder 508 to expose the liquid outlet trough of the fixed cylinder 503; the liquid MgCl2 is thrown out and recovered to the collection box 111 through the liquid pump 110. The structure for realizing this process includes a fixed cylinder 503, a shielding cylinder 508, a third drive motor 501, a second stepper motor 507, a liquid pump 110 and a collection box 111, wherein the centrifugal parameters are adjusted by the height of the shielding cylinder 508 to optimize the separation efficiency. Automated separation improves MgCl2 recovery and allows for reuse. Centrifugal force leverages density differences to achieve rapid stratification. Simultaneously, the heat recovery module returns exhaust from the second reaction zone to the primary reaction chamber 202 via heat exchanger 305 and return pipe 306, achieving a system heat utilization rate of 75% and reducing energy consumption. Upon completion of the reaction, the hafnium sponge remains as a solid, which is removed by opening the lid 304 via the opening and closing mechanism 3.

[0109] The present invention designs a multi-stage gradient reactor for preparing hafnium sponge, comprising a main frame and a feed module. The main frame is composed of a main frame (1), with a fixed plate 101 welded to the top right and a reaction chamber 107 mounted on the left. The feed module comprises two sets of storage cylinders 102 secured to the top of the fixed plate 101. Inside, a screw conveyor 103 driven by a first drive motor 104 is installed. The bottoms of the storage cylinders 102 are connected to a first discharge pipe 105 and fitted with a first valve 106. By precisely controlling the rotational speed of the screw conveyor 103, hafnium tetrachloride (HfCl4) and magnesium metal (Mg) are discharged in a 1:2 molar ratio, minimizing any imbalance in the ratio caused by human error.

[0110] The vibration reaction mechanism 2 comprises a preliminary reaction box 202 connected to the top of the machine body 1 via four sets of springs 201. A top cover 204, controlled by a second electric push rod 203, is located on top of the preliminary reaction box 202. The springs 201 are in contact with the preliminary reaction box 202 and fixedly connected to the top of the machine body 1. A cylinder 205, a vibrating cylinder, is located within the springs 201 and in contact with the preliminary reaction box 202. A fifth electric push rod 214 drives a pressing block 215 to press down the preliminary reaction box 202, triggering rebound vibration of the spring 201. The vibration frequency of the cylinder 205 matches the downward pressure frequency of the fifth electric push rod 214. This vibration ensures thorough mixing of the raw materials at 600–800°C, accelerating the reduction reaction of HfCl₄ + 2Mg to Hf + 2MgCl₂. The side baffle 207 is opened and closed by the third electric push rod 206, and the reaction mixture is transferred through the flip mechanism: the fourth electric push rod 209 drives the card block 213 to snap into the card slot of the preliminary reaction box 202, and the second drive motor 210 drives the box to flip through the drive gear 211 and the driven gear 212.

[0111] The reaction chamber and the movable mechanism are divided into two sections: a first reaction zone (800–1000°C) for enhanced hafnium sponge grain growth and a second reaction zone (1000–1100°C) for melt separation. The partition plate 109 is raised and lowered by a first electric push rod 108. The movable mechanism 4 comprises a second screw 401 driven by a first stepper motor 403, which drives a movable plate 404 along a second guide rod 402. A cylinder 405 is fixed within the movable plate 404. A sealing gasket and sealing groove are provided between the movable plate 404 and the partition plate 109 to ensure a high-temperature inert atmosphere.

[0112] The centrifuge 5 is located below the second reaction zone and comprises a turntable 502 driven by a third drive motor 501. A liquid trough is defined on the outer wall of a fixed cylinder 503, which is fixed at the top. A shielding cylinder 508 is positioned over the fixed cylinder 503 and is raised and lowered by a second stepper motor 507 via a third screw 506. The melt enters the fixed cylinder 503 through a feed channel 509 and a third valve 510. A liquid pump 110 recovers the MgCl2 and transfers it to a collection tank 111.

[0113] The opening and closing mechanism 3 includes two sets of first screws 301 driven by a dual-axis motor 303, which control the sliding of the cover 304 along the first guide rod 302, sealing the strip groove at the top of the reaction chamber 107. After production is completed, the dual-axis motor 303 independently opens the left cover 304, and cooperates with the external unloading device to remove the product. The specific structure is as follows:

[0114] The multi-stage gradient reactor for preparing hafnium sponge includes a body 1, a fixed plate 101 is welded to the right side of the top of the body 1, two sets of storage cylinders 102 are installed on the top of the fixed plate 101, a vibration mechanism 2 is also provided on the right side of the top of the body 1, a reaction chamber 107 is installed on the left side of the top of the body 1, a first electric push rod 108 is provided on the front side of the reaction chamber 107, the output end of the first electric push rod 108 is fixedly connected to the partition plate 109, the reaction chamber 107 is divided into a first reaction area and a second reaction area on the left and right sides by the partition plate 109, an opening and closing mechanism 3 is provided on the top of the reaction chamber 107, and a moving mechanism 4 and a centrifugal mechanism 5 are installed inside the reaction chamber 107, and the moving mechanism 4 drives the reaction material to move between the first reaction area and the second reaction area.

[0115] Please refer to Figure 1 and Figure 2 As shown, the storage barrel 102 is internally connected to a rotatable screw conveyor rod 103, which is driven by a first drive motor 104 outside the storage barrel 102. The bottom left end of the storage barrel 102 is connected to a first discharge pipe 105, and a first valve 106 is installed on the first discharge pipe 105. Two sets of storage barrels 102 are also provided, each storing hafnium tetrachloride and metallic magnesium. By controlling the rotation speed of the output end of the first drive motor 104, the rotation speed of the screw conveyor rod 103 is controlled, achieving quantitative discharge of hafnium tetrachloride and metallic magnesium. In the present invention, the preparation of hafnium sponge requires that hafnium tetrachloride and metallic magnesium be charged in a 1:2 molar ratio. By opening the first valve 106, the 1:2 molar ratio of hafnium tetrachloride and metallic magnesium is added to the interior of the vibration mechanism 2.

[0116] Please refer to Figure 3 and Figure 4As shown, the vibration mechanism 2 includes four groups of springs 201. The top right side of the body 1 is fixedly connected to the bottom of the preliminary reaction box 202 through the four groups of springs 201. Two groups of second electric push rods 203 are provided on the top of the preliminary reaction box 202. A top cover 204 is provided on the top of the preliminary reaction box 202. The outer side of the top cover 204 is fixedly installed on the output end of the second electric push rod 203, and a discharge slot is provided on the left side of the preliminary reaction box 202. A baffle 207 is installed at the position of the discharge slot. The top of the baffle 207 is fixedly connected to the output end of the third electric push rod 206. The third electric push rod 206 is arranged at the top left side of the preliminary reaction box 202. A cylinder 205 is provided inside one group of springs 201. A fifth electric push rod 214 is fixedly installed on the left side of the fixed plate 101. The output end of the fifth electric push rod 214 is fixedly connected to the pressure block 215.

[0117] Please refer to Figure 4 As shown, the vibration mechanism 2 also includes two groups of support plates 208, which are respectively located on the front and rear sides of the preliminary reaction box 202. The internal rotation of the support plates 208 is connected to the fourth electric push rod 209, and the output end of the fourth electric push rod 209 is fixedly connected to the block 213. The front and rear sides of the preliminary reaction box 202 are both provided with a card slot adapted to the block 213. A second drive motor 210 is provided on the outer side of one group of support plates 208, and the output end of the second drive motor 210 is fixedly connected to the drive gear 211. The outer surface of one group of fourth electric push rods 209 is fixedly mounted with a driven gear 212 meshing with the drive gear 211.

[0118] When hafnium tetrachloride and magnesium metal are in a 1:2 molar ratio inside the preliminary reaction box 202, the temperature inside the preliminary reaction box 202 is strictly controlled at 600-800°C. The extension of the output end of the fifth electric push rod 214 drives the pressure block 215 to move downward, causing the preliminary reaction box 202 to move downward. The four groups of springs 201 are all in a contracted state. Subsequently, the output end of the fifth electric push rod 214 is quickly reset. Under the action of the four groups of springs 201 recovering their deformation, the cylinder 205 is a vibrating cylinder with the same action frequency as the fifth electric push rod 214, so that the preliminary reaction box 202 can be stably vibrated up and down, accelerating the contact of the reactants and triggering the preliminary reaction box 202. The reduction reaction HfCl4+2Mg→Hf+2MgCl2 is carried out in the next step. After the reaction is completed, the output end of the third electric push rod 206 contracts, driving the baffle 207 to move upward, opening the discharge slot opened on the left side of the preliminary reaction box 202, and the output end of the cylinder 205 is reset. The output ends of the fourth electric push rods 209 on both sides extend to drive the two groups of clamping blocks 213 to be respectively clamped in the clamping slots on the front and rear sides of the preliminary reaction box 202, and then the output end of the second drive motor 210 drives the drive gear 211 to rotate, so that the preliminary reaction box 202 rotates, thereby allowing the Hf and MgCl2 generated after the reaction to enter the interior of the cylinder 405.

[0119] Please refer to Figure 5 As shown, the opening and closing mechanism 3 includes a first screw rod 301 and a first guide rod 302. The first screw rod 301 is provided with two groups that are rotatably connected to the two sides of the top of the reaction chamber 107. The first guide rod 302 is provided with two groups that are respectively welded to the two sides of the top of the reaction chamber 107. The outer surface of the first screw rod 301 is threadedly connected with a cover 304. The two groups of covers 304 respectively cover the strip grooves opened on both sides of the top of the reaction chamber 107, and a dual-axis motor 303 is also fixedly installed on the top of the reaction chamber 107. The two output ends of the dual-axis motor 303 are respectively fixedly connected to the first screw rod 301 on both sides.

[0120] Those skilled in the art will understand that by controlling the two output ends of the dual-axis motor 303 to rotate independently or synchronously, it is possible to control the rotation of the first screw rod 301 on one side or the synchronous rotation of the first screw rods 301 on both sides, thereby controlling the opening or closing of the cover 304 on one side or the synchronous opening or closing of the covers 304 on both sides.

[0121] Please refer to Figure 6 and Figure 7 As shown, the moving mechanism 4 includes a second screw rod 401 and a movable plate 404, the second screw rod 401 is rotatably connected to the inside of the reaction chamber 107, the movable plate 404 is threadedly connected to the outer surface of the second screw rod 401, the movable plate 404 is slidably installed on the second guide rod 402, the second guide rod 402 is welded to the inside of the reaction chamber 107, the outer end of the second screw rod 401 is fixedly installed on the output end of the first stepper motor 403, the first stepper motor 403 is arranged on the outside of the reaction chamber 107, and the interior of the movable plate 404 is fixedly connected to the cylinder 405, the bottom of the cylinder 405 is provided with a second discharge channel 406, the second discharge channel 406 is installed with a second valve 407, and a sealing gasket and a sealing groove structure are provided between the movable plate 404 and the partition plate 109.

[0122] The interior of the reaction chamber 107 is divided into a first reaction area and a second reaction area by a partition plate 109. The side close to the preliminary reaction box 202 is the first reaction area, and the temperature of the first reaction area is strictly controlled at 800-1000°C, while the other side is the second reaction area, and the temperature of the second reaction area is strictly controlled at 1000-1100°C. The second screw 401 is driven to rotate by the output end of the first stepper motor 403, so that the movable plate 404 reciprocates left and right. By controlling the extension of the output end of the first electric push rod 108, the partition plate 109 is driven to move upward, thereby driving the movable plate 404 to move between the first reaction area and the second reaction area, and driving the cylinder 405 to move between the first reaction area and the second reaction area.

[0123] Please refer to Figure 8 and Figure 9 As shown, the centrifugal mechanism 5 includes a third drive motor 501 fixedly installed on the left side of the bottom of the body 1. The output end of the third drive motor 501 passes through the bottom wall of the body 1 and is fixedly connected to the turntable 502. The top of the turntable 502 is fixedly connected to a fixed cylinder 503. The outer surface of the fixed cylinder 503 is evenly penetrated with a plurality of groups of liquid outlet grooves, and the outer surface of the fixed cylinder 503 is provided with a shielding cylinder 508.

[0124] Please refer to Figure 8 and Figure 9 As shown, the top of the turntable 502 is fixedly connected to the top plate 505 through two groups of third guide rods 504, and a third screw rod 506 is rotatably connected between the top plate 505 and the turntable 502. The top of the third screw rod 506 is fixedly connected to the output end of the second stepper motor 507, and the second stepper motor 507 is arranged at the top of the top plate 505. The shielding cylinder 508 is threadedly connected to the outer surface of the third screw rod 506, and the shielding cylinder 508 is slidably connected to the third guide rod 504, and a feed channel 509 is installed on the top of the shielding cylinder 508, and a third valve 510 is provided on the outer wall of the feed channel 509.

[0125] Please refer to Figure 1 and Figure 5 As shown, the top of the cover 304 located above the second reaction area is connected to a heat exchanger 305, and the output end of the heat exchanger 305 is connected to the preliminary reaction box 202 through the return air pipe 306, and a liquid pump 110 is provided on the front side of the body 1, and the input end of the liquid pump 110 is connected to the second reaction area through the liquid inlet pipe, and a collection box 111 is provided below the output end of the liquid pump 110.

[0126] The output end of the second stepper motor 507 drives the third screw rod 506 to rotate, so that the shielding tube 508 moves up and down. When moving downward, the shielding tube 508 covers the fixed tube 503, and when moving upward, the shielding tube 508 does not cover the fixed tube 503, thus exposing the liquid outlet groove opened on the outer surface of the fixed tube 503.

[0127] In order to clearly describe the working process of the above device, we use Figure 1 The following is an explanation of the azimuth perspective:

[0128] Two sets of storage cylinders 102 are provided, each storing hafnium tetrachloride and metallic magnesium therein. By controlling the rotation speed of the output end of the first drive motor 104, the rotation speed of the screw conveying rod 103 is controlled to achieve quantitative feeding of hafnium tetrachloride and metallic magnesium. In the present invention, the preparation of hafnium sponge requires feeding hafnium tetrachloride and metallic magnesium in a molar ratio of 1:2. By opening the first valve 106, the hafnium tetrachloride and metallic magnesium in a molar ratio of 1:2 are added to the interior of the preliminary reaction box 202.

[0129] The temperature inside the preliminary reaction box 202 is strictly controlled at 600-800°C. The extension of the output end of the fifth electric push rod 214 drives the pressing block 215 to move downward, causing the preliminary reaction box 202 to move downward. The four sets of springs 201 are all in a contracted state. Subsequently, the output end of the fifth electric push rod 214 is quickly reset. Under the action of the four sets of springs 201 recovering their deformation, the preliminary reaction box 202 is able to vibrate stably up and down, accelerating the contact of the reactants and triggering the preliminary reduction reaction HfCl4+2Mg→Hf+2MgCl2.

[0130] The output end of the first stepper motor 403 drives the second screw rod 401 to rotate, so that the movable plate 404 moves to the side close to the preliminary reaction box 202, and drives the cylinder 405 to move to the side close to the preliminary reaction box 202. After the reaction is completed, the output end of the third electric push rod 206 contracts, driving the baffle 207 to move upward, opening the discharge slot opened on the left side of the preliminary reaction box 202, and the output end of the cylinder 205 is reset. The output ends of the fourth electric push rods 209 on both sides extend and drive the two sets of card blocks 213 to be respectively stuck in the card slots on the front and rear sides of the preliminary reaction box 202. Then, the output end of the second drive motor 210 drives the drive gear 211 to rotate, so that the preliminary reaction box 202 rotates, thereby causing the Hf and MgCl generated after the reaction to be discharged. 2进入 Inside the cylinder 405.

[0131] The cylinder 405 is located in the first reaction zone, and the temperature in the first reaction zone is strictly controlled at 800-1000° C. to enhance the growth of metal hafnium grains.

[0132] After the reaction in the first reaction area is completed, the extension of the output end of the first electric push rod 108 drives the partition plate 109 to move upward, and then under the action of the output end of the first stepper motor 403, the cylinder 405 moves to the second reaction area and is located directly above the feed channel 509 at the top of the shielding cylinder 508. Then the output end of the first electric push rod 108 is immediately reset, and the temperature of the second reaction area is strictly controlled at 1000-1100°C. The second valve 407 and the third valve 510 are opened, allowing the reactants to flow out of the cylinder 405 and enter the shielding cylinder 508. 8, that is, into the interior of the fixed cylinder 503. After the reaction is completed, under the action of the output end of the third drive motor 501, centrifugal action is performed, and the output end of the second stepping motor 507 drives the third screw rod 506 to rotate, thereby causing the shielding cylinder 508 to move upward. The shielding cylinder 508 does not cover the fixed cylinder 503, and the liquid outlet groove opened on the outer surface of the fixed cylinder 503 is exposed, thereby achieving high-temperature separation, and discharging the liquid molten MgCl2 into the second reaction area. The liquid MgCl2 is extracted by the liquid pump 110 and enters the collection box 111.

[0133] The high-temperature exhaust gas in the second reaction area is returned to the preliminary reaction box 202 through the output end of the heat exchanger 305 and the return air pipe 306. The system heat utilization rate is increased to 75%, and the production is fully automated. After the production is completed, the output end on the left side of the dual-axis motor 303 rotates independently, controlling the opening of the left cover 304, and the material is taken away through an external material removal device, which is convenient and fast, meeting the needs of the staff.

[0134] The heat recovery system efficiently recovers the energy from the high-temperature exhaust gas in the second reaction zone through heat exchanger 305 and safely directs the treated airflow back to the primary reaction chamber 202 to support continuous production. Heat exchanger 305 is directly connected to the cover 304 above the second reaction zone, which is sealed and controlled by an opening and closing mechanism 3. At heat exchanger 305, the high-temperature exhaust gas first undergoes preliminary filtration to remove potential impurities. A cyclone separator is installed at the inlet of heat exchanger 305 to capture large metal particles and unreacted products. A ceramic fiber filter is installed at the outlet of heat exchanger 305 to absorb magnesium chloride vapor and fine pollutants. After leaving heat exchanger 305, the purified airflow is transported to the primary reaction chamber 202 through return air pipe 306, which is made of corrosion-resistant materials and sprayed with a special anti-corrosion coating on the inner wall to enhance long-term operational durability. The middle section of the return air pipe 306 is equipped with an integrated temperature buffer device, a built-in sensor and an adjustment mechanism to stabilize the air flow temperature to a suitable range of 600-800°C, thereby avoiding environmental fluctuations in the preliminary reaction box 202. The proportional control valve is driven by a stepper motor and automatically adjusts the exhaust gas flow rate according to the temperature feedback signal of the preliminary reaction box 202 to ensure that the reduction reaction proceeds smoothly. All components are seamlessly connected to the main frame of the machine body 1 through standard industrial interfaces. The entire system can be managed by an adaptive PID algorithm of the central control unit to dynamically optimize heat exchange parameters and improve overall energy efficiency. The regulated gas is injected into the preliminary reaction box 202 to participate in the heat supply of the reduction reaction process of hafnium tetrachloride and metallic magnesium, thereby realizing energy recycling.

[0135] Example 1. This example is directed to the implementation of a hafnium sponge preparation process in an industrial production scenario. First, the operator loads hafnium tetrachloride and metallic magnesium into two independent storage cylinders 102, respectively. The first drive motor 104 drives the screw conveyor rod 103 to rotate, and simultaneously opens the first valve 106 to adjust the flow rate of the first discharge pipe 105, so that the two raw materials enter the interior of the preliminary reaction box 202 in a precise molar ratio of 1:2.

[0136] Next, step S2 is executed. The preliminary reaction box 202 starts a vibration acceleration reaction at a constant temperature of 700°C. The fifth electric push rod 214 drives the pressure block 215 to press the box downward, causing the four sets of springs 201 to contract synchronously. The springs 201 then recover their deformation and push the box to vibrate at a high frequency. At the same time, the cylinder 205 located inside the spring 201 expands and contracts at the same frequency, accelerating the reduction reaction of hafnium tetrachloride and metallic magnesium. The conversion of HfCl4 + 2Mg to Hf + 2MgCl2 is completed within 20 minutes, generating a solid mixture of hafnium and magnesium chloride.

[0137] After entering step S3, the third electric push rod 206 controls the baffle 207 to rise and open the discharge slot, the fourth electric push rod 209 drives the card block 213 to engage with the card slot of the preliminary reaction box 202, and the second drive motor 210 drives the box body to flip 120° through the driving gear 211 and the driven gear 212 to allow the mixture to fall completely into the cylinder 405.

[0138] Then, step S4 is executed. The first stepper motor 403 drives the second screw 401 to rotate, causing the movable plate 404 to slide along the second guide rod 402 to the first reaction zone at 800-1000°C. At this point, the permanent magnet array 63 composed of 24 iron-cobalt-vanadium-based permanent magnet alloy magnets inside the cylinder 405 is activated. The magnets are arranged with alternating north poles 631 and south poles 632 to form a radial static magnetic field. The permalloy magnetic conductive layer 65, deposited on the inside of the yttrium-zirconium liner 64 via a magnetron sputtering process, focuses the magnetic field lines at the center of the cylinder. This magnetic field suppresses microturbulence in the molten magnesium chloride and reduces the diffusion of oxygen atoms. After 30 minutes of constant temperature, the grain size reaches 80μm.

[0139] During step S5, first electric push rod 108 raises partition plate 109, and first stepper motor 403 drives cylinder 405 to the second reaction zone at 1000-1100°C. Second valve 407 and third valve 510 are opened, and the molten mixture enters fixed cylinder 503 through second discharge channel 406 and feed channel 509.

[0140] Finally, step S6 is executed, and the second stepper motor 507 drives the third screw 506 to rotate so that the shielding cylinder 508 rises to expose the fixed cylinder 503 at the liquid outlet tank, and the third drive motor 501 drives the turntable 502 to centrifuge at a speed of 1200 r / min; after the liquid magnesium chloride is discharged from the liquid outlet tank, it is recovered by the liquid pump 110 to the collection box 111, and the heat recovery system efficiently recovers the high-temperature exhaust gas energy in the second reaction area through the heat exchanger 305, and safely guides the treated airflow back to the preliminary reaction box 202 to support continuous production. At heat exchanger 305, the high-temperature exhaust gas first undergoes preliminary filtration to remove potential impurities. A cyclone separator is installed at the inlet of heat exchanger 305 to capture large metal particles and unreacted products. A ceramic fiber filter is installed at the outlet of heat exchanger 305 to absorb magnesium chloride vapor and fine pollutants. After leaving heat exchanger 305, the purified airflow is transported to the preliminary reaction box 202 through return air pipe 306. This return air pipe 306 is made of corrosion-resistant materials and has a special anti-corrosion coating sprayed on its inner wall to enhance long-term operational durability. A temperature buffer device is integrated in the middle section of return air pipe 306. It has a built-in sensor and adjustment mechanism to stabilize the airflow temperature to an appropriate range of 600-800°C, thereby preventing environmental fluctuations in the preliminary reaction box 202.

[0141] Comparative Example 1: This comparative example uses an ordinary alumina ceramic container with a wall thickness of 10 mm and no magnetic field function. Other implementation conditions are consistent with Example 1. During the specific implementation, in step S4, when the container is moved to the first reaction zone at 800-1000°C, due to the lack of the permanent magnet array 63 and the permalloy magnetic conductive layer 65, a focused magnetic field cannot be generated, resulting in random diffusion of the hafnium sponge atoms.

[0142] The performance comparison of hafnium sponge prepared in Example 1 and Comparative Example 1 is shown in Table 1.

[0143] Table 1 Comparison of properties of hafnium sponge prepared in Example 1 and Comparative Example 1

[0144]

[0145] As can be seen from Table 1, Example 1 of the present invention achieves a significant improvement in the preparation performance of hafnium sponge through the technical solution of a multi-stage gradient reactor. Specifically, in terms of grain structure, the average grain size of Example 1 reaches 80±5 microns, while that of Comparative Example 1 is only 45±20 microns, with a difference rate of 44%; the permanent magnet array and the permalloy magnetic conductive layer inside the cylinder of the present invention synergistically form a radial static magnetic field, which suppresses the micro-turbulence of the molten magnesium chloride by focusing the magnetic lines of force on the central area of ​​the cylinder, greatly reducing the oxygen diffusion coefficient and significantly reducing the migration of oxygen to the grain boundaries; the static magnetic field suppresses the micro-turbulence of the molten magnesium chloride, reduces the oxygen diffusion coefficient, and reduces the migration of oxygen to the grain boundaries; under a temperature environment of 800-1000°C, in the low-oxygen grain boundary environment synergistically with the thermal gradient effect, the hafnium grains grow to form uniformly distributed radial crystals.

[0146] Since the inert protective layer of the yttrium zirconium lining effectively blocks the reaction between the melt and the container, and the static magnetic field suppresses the micro-turbulence of the magnesium chloride melt and reduces the diffusion of oxygen atoms to the grain boundaries, the dual effects reduce the probability of impurity adsorption. In terms of chemical purity, the oxygen content of Example 1 is 180 ppm, which is much lower than the 600 ppm of Comparative Example 1, and the total impurity content is only 250 ppm.

[0147] The uniform columnar crystal structure induced by the magnetic field reduces the phenomenon of grains encapsulating molten magnesium chloride. Combined with the precise separation control of the shielding cylinder in the centrifugal mechanism, the molten salt discharge efficiency is significantly improved. In terms of separation effect, the residual magnesium chloride in Example 1 is only 0.3wt%, which is 500% lower than the 1.8wt% in Comparative Example 1.

[0148] In terms of physical and mechanical properties, the high-purity and high-orientation grain structure reduces the weakening effect of grain boundary impurities, making the microstructure of hafnium sponge more dense and stable. The hardness of Example 1 reaches 215±8 HV0.3, which is 16% higher than that of Comparative Example 1, and the thermal expansion coefficient is reduced to 5.9×10 -6 / K.

[0149] The innovative technical solution of the present invention achieves significant improvements in the grain integrity, chemical purity and physical and mechanical properties of sponge hafnium products through the synergistic effects of three core mechanisms: magnetic field directional control, inert lining protection and gradient temperature zoning, from atomic arrangement optimization, interface reaction suppression to macroscopic separation enhancement.

[0150] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A multi-stage gradient reactor for preparing hafnium sponge, characterized in that: include: body; A fixing plate fixed to the top of the machine body, and a storage cylinder installed on the top of the fixing plate; A first discharge pipe connected to the bottom of the storage cylinder, a first valve provided on the first discharge pipe; a reaction chamber installed on the left side of the top of the body, and a partition plate provided inside the reaction chamber; A first electric push rod, a liquid pump and a collection box for driving the separation plate to rise and fall; The vibration mechanism includes a preliminary reaction box connected to the top of the machine body by a spring, a fifth electric push rod and a pressure block for driving the vibration of the preliminary reaction box, a third electric push rod and a baffle for controlling the opening and closing of the discharge slot, a fourth electric push rod for driving the flip, a clamping block, a second drive motor, a drive gear, and a driven gear; The moving mechanism includes a second screw driven by a first stepper motor, a movable plate slidably mounted on the second guide rod, a cylinder fixed inside the movable plate, a second discharge channel connected to the bottom of the cylinder, and a second valve provided on the second discharge channel; From the inside out, the cylinder is sequentially equipped with a permalloy magnetic conductive layer, a yttrium zirconium liner, a permanent magnet array, and a steel shell. The permalloy magnetic conductive layer is plated on the inside of the yttrium zirconium liner through a magnetron sputtering process, focusing the magnetic field lines on the material at the center of the cylinder. The yttrium zirconium liner is provided with guide grooves, and the front and rear ends of the permanent magnet array are respectively embedded in the guide grooves of the yttrium zirconium liner and the ceramic glue. The steel shell is the outermost layer. The permanent magnet array consists of 24 iron-cobalt-vanadium-based permanent magnet alloy magnets evenly distributed along the circumference of the cylinder, with each magnet having an angular width of 12 degrees. The iron-cobalt-vanadium-based permanent magnet alloy magnets of the permanent magnet array are arranged alternately with north and south poles and fixed by ceramic glue. An insulation layer is filled between the outer steel shell and the ceramic glue, and the insulation layer is composed of a silicon nitride layer and zirconium oxide fiber felt. The centrifugal mechanism includes a turntable driven by a third drive motor, a fixed cylinder fixed to the top of the turntable, a shielding cylinder sleeved on the outside of the fixed cylinder, a second stepping motor and a third screw for controlling the lifting and lowering of the shielding cylinder, a feed channel connected to the feed channel, and a third valve provided on the feed channel; The heat recovery module includes a heat exchanger and a return air pipe connected to the top of the reaction chamber, and the return air pipe is connected to the preliminary reaction box.

2. The multi-stage gradient reactor for preparing hafnium sponge according to claim 1, characterized in that: In the moving mechanism, the movable plate is connected to the second screw rod through a thread and is slidably installed on the second guide rod, and a sealing gasket and a sealing groove structure are provided between the movable plate and the partition plate.

3. The multi-stage gradient reactor for preparing hafnium sponge according to claim 1, characterized in that: The centrifugal mechanism further comprises a third guide rod fixedly connected to the turntable and the top plate, and the third guide rod is slidably connected to the shielding cylinder.

4. The multi-stage gradient reactor for preparing hafnium sponge according to claim 1, characterized in that: In the vibration mechanism, the cylinder is arranged inside the spring, and the vibration frequency of the pressing block driven by the fifth electric push rod is synchronized with the expansion and contraction frequency of the cylinder.

5. The multi-stage gradient reactor for preparing hafnium sponge according to claim 1, characterized in that: A heat insulation layer is filled between the steel shell and the ceramic glue, and the heat insulation layer is composed of a silicon nitride layer and zirconium oxide fiber felt.

6. A method for preparing hafnium sponge by multi-stage gradient reaction using the reactor according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1: Load hafnium tetrachloride and magnesium metal into their respective storage cylinders, and control the raw materials to enter the preliminary reaction box; S2: The initial reaction box is accelerated by mechanical vibration at 600-800°C, and the system completes the reduction reaction of hafnium tetrachloride to produce a mixture of hafnium and magnesium chloride; S3: turning over the preliminary reaction box to allow the hafnium and magnesium chloride mixture to fall into the cylinder; S4: The cylinder moves to the first reaction zone at 800-1000°C. The permanent magnet array inside the cylinder consists of 24 iron-cobalt-vanadium-based permanent magnet alloy magnets evenly distributed along the circumference of the cylinder, with N and S poles alternating, forming a radial static magnetic field. A permalloy magnetic conductive layer plated on the inner side of the yttrium-zirconium liner converges the static magnetic field lines generated by the permanent magnet array to the center of the cylinder. The static magnetic field suppresses the micro-turbulence of the molten magnesium chloride, reduces the oxygen diffusion coefficient, and reduces the migration of oxygen to the grain boundaries. At a temperature of 800-1000°C, the hafnium grains grow to form uniformly distributed radial crystals under the synergistic thermal gradient effect of the low-oxygen grain boundary environment. S5: moving the cylinder to the second reaction zone at 1000-1100°C, allowing the hafnium sponge and molten magnesium chloride to enter the centrifugal fixed cylinder; S6: Magnesium chloride is discharged from the fixed cylinder through centrifugal separation, and the liquid pump recovers it to the collection box. At the same time, the high-temperature exhaust gas returns to the preliminary reaction box through the heat recovery system.

7. The method according to claim 6, characterized in that S1 and S2 include the following specific steps: S11: Hafnium tetrachloride and magnesium metal are loaded into storage cylinders respectively, and the screw conveying rod is driven to rotate by a first driving motor; S12: Open the first valve to adjust the flow rate of the first discharge pipe so that hafnium tetrachloride and metallic magnesium enter the preliminary reaction box at a molar ratio of 1:2; S21: Under the environment of 600-800℃, the fifth electric push rod drives the pressing block to press the preliminary reaction box to contract the spring, and then the spring recovers its deformation to push the preliminary reaction box to vibrate up and down; S22: The cylinder is located inside the spring, and its expansion and contraction frequency is synchronized with the vibration frequency of the fifth electric push rod, accelerating the reaction to generate a mixture of hafnium and magnesium chloride.

8. The method according to claim 6, characterized in that The specific steps of S3 and S4 include: S31: The third electric push rod controls the baffle to rise and open the discharge slot of the preliminary reaction box; S32: The fourth electric push rod drives the card block to engage with the card slot of the preliminary reaction box; S33: The second driving motor drives the preliminary reaction box to flip through the driving gear and the driven gear, so that the mixture falls into the cylinder; S41: The first stepper motor drives the second screw to rotate, and the movable plate slides along the second guide rod, driving the cylinder to move to the first reaction area of ​​800-1000°C for crystal nucleus growth.

9. The method according to claim 6, characterized in that The specific steps of S5 and S6 include: S51: The first electric push rod drives the partition plate to rise; S52: The first stepper motor drives the second screw to rotate, and the movable plate slides along the second guide rod, driving the cylinder to move to the second reaction area of ​​1000-1100°C; S53: Open the second valve and the third valve to allow the molten hafnium sponge and magnesium chloride to enter the fixed cylinder through the second discharge channel and the feed channel; S61: The second stepper motor drives the third screw to rotate, controlling the shielding cylinder to rise and expose the liquid outlet groove of the fixed cylinder; S62: The third driving motor drives the turntable to rotate, and the liquid magnesium chloride is discharged from the liquid outlet tank through centrifugal separation; S63: The liquid pump recovers the liquid magnesium chloride to a collection tank; S64: The high-temperature exhaust gas is purified and returned to the preliminary reaction box through a heat exchanger and a return air pipe for heat reuse.

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