An on-line refining and homogenizing method for preparing magnesium-rare earth intermediate alloy by fused salt electrolytic codeposition

Abstract

The application discloses an on-line refining and homogenizing method for preparing a magnesium-rare earth intermediate alloy by molten salt electrolysis co-deposition. The on-line refining and homogenizing method comprises the following steps: preheating a material taking container to a temperature at which the magnesium-rare earth intermediate alloy can be kept in a molten or semi-molten state; and during the process of preparing the magnesium-rare earth intermediate alloy by molten salt electrolysis co-deposition or when the electrolysis is finished, taking out the fish-seed-shaped magnesium-rare earth intermediate alloy by using the preheated material taking container, and carrying out heat preservation, stirring, static stratification, salt removal and casting forming treatment, so as to realize the on-line refining and homogenizing of the magnesium-rare earth intermediate alloy prepared by molten salt electrolysis co-deposition. The application directly completes stirring, static stratification and salt removal refining in the material taking process by using the high-temperature state of the electrolysis product, reduces the secondary remelting process and energy consumption, can reduce the alloy salt content, reduce the oxidation loss of rare earth elements, and improve the gathering effect, composition uniformity and alloy yield of the fish-seed-shaped alloy.

Description

Technical Field

[0001] This invention belongs to the field of alloy purification technology, specifically relating to an online refining and homogenization method for preparing magnesium rare earth master alloys by molten salt electrolytic co-deposition. Background Technology

[0002] Molten salt electrolytic co-deposition is one of the main methods for preparing magnesium rare earth (Mg-RE) master alloys. It typically uses a chloride molten salt system such as MgCl2-RECl3-KCl, where magnesium and rare earth ions are co-reduced near the cathode via direct current electrolysis in an electrolytic cell to form the Mg-RE master alloy. However, in actual electrolysis, due to factors such as temperature fluctuations, uneven current density, changes in the cathode surface state, and molten salt entrainment, the Mg-RE alloy precipitated at the cathode often fails to completely aggregate into a continuous metallic phase, instead existing as fine particles or loose agglomerates, commonly known as "fish roe" alloys. These alloy particles easily trap large amounts of high-temperature molten electrolyte on their surface and in their gaps. If directly cooled and solidified, a significant amount of salt inclusions remain, affecting the alloy's purity, microstructure uniformity, and subsequent performance.

[0003] Currently, the closest existing technical solution to this invention is to perform offline remelting and refining of the fish roe-like or salt-infused magnesium rare earth alloy produced by electrolysis. The typical procedure is as follows: the fish roe-like alloy or salt-infused alloy taken from the electrolytic cell is transferred to a preheated refining crucible and reheated to a temperature above the alloy liquidus line, typically 750–850°C, under a protective atmosphere or flux covering. Then, refining flux is added and mechanically stirred, causing oxide inclusions, residual electrolytes, and non-metallic inclusions to be adsorbed by the flux or carried into the slag. After settling and stratification, the slag and residual electrolytes are removed, and finally, the molten metal is cast into ingots.

[0004] In addition, existing technologies also employ specialized purification devices, filtration structures, or multi-stage separation structures to purify inclusions in magnesium alloy melts, such as the multi-stage purification device disclosed in CN116622993A. These methods primarily rely on independent equipment for subsequent purification of the formed alloy melt, which can reduce inclusion content to some extent, but typically require additional equipment and independent processing procedures.

[0005] The shortcomings of the above-mentioned offline refining or dedicated purification solutions are as follows: First, the electrolysis and refining processes are separated, requiring the materials to be transferred to independent crucibles or purification equipment, resulting in a long operation process; Second, the fish roe-like alloys need to be reheated and melted, consuming additional heat energy; Third, magnesium and rare earth elements are prone to oxidation and burn-off during secondary heating and transfer, affecting the alloy yield; Fourth, dedicated purification devices have relatively complex structures and high equipment investment, which is not conducive to flexible application in the laboratory or pilot-scale stages.

[0006] Therefore, there is an urgent need for a simple method that can utilize the high temperature of the electrolysis products themselves to instantly complete the aggregation, desalination, refining, and homogenization of fish roe-like magnesium rare earth alloys during the material extraction process. Summary of the Invention

[0007] The main objective of this invention is to provide an online refining and homogenization method for preparing magnesium rare earth master alloys by molten salt electrolytic co-deposition, so as to overcome the shortcomings of the prior art.

[0008] To achieve the aforementioned objectives, the technical solution adopted by this invention includes:

[0009] This invention provides an online refining and homogenization method for preparing magnesium rare earth master alloys by molten salt electrolytic co-deposition, comprising:

[0010] Preheat the material receiving container to the temperature at which the magnesium rare earth intermediate alloy remains in a molten or semi-molten state.

[0011] Furthermore, during the preparation of magnesium rare earth master alloys by molten salt electrolytic co-deposition or during electrolytic discharge, a preheated material handling container is used to remove the fish roe-like magnesium rare earth master alloy, which is then subjected to heat preservation, stirring, static layering, salt removal, and casting molding processes, thereby achieving online refining and homogenization of magnesium rare earth master alloys prepared by molten salt electrolytic co-deposition.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows: Compared with the existing offline remelting and refining methods, the present invention utilizes the high temperature state of the electrolytic products themselves to directly complete stirring, aggregation, static stratification and salt removal refining during the material extraction process, reducing the secondary remelting process and energy consumption; at the same time, the present invention can reduce the amount of salt in the alloy, reduce the oxidation loss of rare earth elements, and improve the aggregation effect, composition uniformity and alloy yield of the fish roe alloy. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram of the online refining and homogenization process for preparing magnesium rare earth master alloys by molten salt electrolytic co-deposition in a typical embodiment of the present invention.

[0015] Figures 2-3 This is a comparison diagram of the magnesium rare earth intermediate alloy state before and after the online refining and homogenization method used in Embodiment 1 of the present invention. Detailed Implementation

[0016] This invention addresses the problems encountered during the preparation of magnesium rare earth master alloys via molten salt electrolytic co-deposition. The alloy products retrieved from the bottom of the electrolytic cell are often in a roe-like, granular, or dispersed state, leading to difficulties in metal aggregation, high residual electrolyte entrainment, difficulty in separating the alloy from the molten salt, low product yield, irregular alloy morphology, and insufficient compositional uniformity. The invention provides a refining and homogenization method for the retrieved electrolytic products. By subjecting the roe-like magnesium rare earth alloy retrieved to heat preservation, stirring, and static stratification in a scoop, the dispersed metal phase is encouraged to aggregate into a continuous or plate-like alloy phase. Simultaneously, effective separation of the residual molten salt electrolyte from the metal phase is achieved, thereby reducing the amount of salt entrainment in the alloy, improving the degree of alloy aggregation, yield, and compositional uniformity, and obtaining a magnesium rare earth master alloy that is easy to cast, sample, and apply.

[0017] The technical solution of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] This invention involves extracting a fish-roe-like magnesium rare earth alloy from the bottom of the electrolytic cell or the cathode area during electrolysis or at the discharge point. Taking advantage of its still-high temperature, the alloy is subjected to heat preservation, stirring, settling, and salt removal processes in a receiving container. Specifically, heat preservation keeps the fish-roe-like alloy and entrained molten electrolyte in a flowing state; stirring causes the dispersed alloy particles to collide, break down surface salt films, and fuse, gradually agglomerating into a continuous metallic phase; after stirring stops, the alloy is allowed to settle, allowing the residual molten electrolyte and metallic phase to separate; subsequently, the residual electrolyte is removed by pouring, scraping, or draining, yielding the agglomerated magnesium rare earth alloy, which is then further cast or transferred for later use. This method enables online refining and homogenization of the fish-roe-like alloy during the electrolysis discharge process, eliminating the need for a separate remelting and refining step.

[0019] Specifically, as one aspect of the technical solution of this invention, an online refining and homogenization method for preparing magnesium rare earth master alloys by molten salt electrolytic co-deposition includes:

[0020] Preheat the material receiving container to the temperature at which the magnesium rare earth intermediate alloy remains in a molten or semi-molten state.

[0021] Furthermore, during the preparation of magnesium rare earth master alloys by molten salt electrolytic co-deposition or during electrolytic discharge, a preheated material handling container is used to remove the fish roe-like magnesium rare earth master alloy, which is then subjected to heat preservation, stirring, static layering, salt removal, and casting molding processes, thereby achieving online refining and homogenization of magnesium rare earth master alloys prepared by molten salt electrolytic co-deposition.

[0022] In some preferred embodiments, the online refining and homogenization method specifically includes:

[0023] (1) Preheat the material receiving container to the temperature at which the magnesium rare earth intermediate alloy remains in a molten or semi-molten state;

[0024] (2) During the preparation of magnesium rare earth intermediate alloy by molten salt electrolytic co-deposition or during electrolytic discharge, a preheated material collection container is used to take out the fish roe-shaped magnesium rare earth intermediate alloy from the bottom of the electrolytic cell, the cathode area or the alloy collection area; the fish roe-shaped magnesium rare earth intermediate alloy particles contain a small amount of molten electrolyte.

[0025] (3) Keep the container containing the fish roe-shaped magnesium rare earth intermediate alloy in the electrolysis device to keep the material in the container in a molten or semi-molten state.

[0026] (4) Use a stirring tool to stir the fish roe-like magnesium rare earth intermediate alloy in the heat-insulated material container;

[0027] (5) After stopping stirring, continue to keep it warm and stand so that the residual molten electrolyte and magnesium rare earth intermediate alloy separate into layers;

[0028] (6) The residual molten electrolyte after stratification is poured back into the electrolytic cell or discharged into the waste salt collection container by means of dumping, scraping or diversion, and the magnesium rare earth intermediate alloy after aggregation is collected.

[0029] (7) Pour the aggregated magnesium rare earth intermediate alloy into a preheated mold to cool and form, or transfer it to an intermediate ladle or ingot mold for later use.

[0030] Furthermore, the temperature at which the molten or semi-molten state is maintained is 700–800°C.

[0031] Furthermore, the material receiving container is provided with a heat insulation layer and an inner wall isolation coating; the inner wall isolation coating includes boron nitride or yttrium oxide.

[0032] Furthermore, the material receiving container may be constructed with a structure resistant to high temperatures and molten salt corrosion.

[0033] Furthermore, in step (3), the material inside the material taking container is kept in a molten or semi-molten state by utilizing the heat insulation structure of the material taking container, the residual heat of the fish roe-shaped magnesium rare earth intermediate alloy itself, or auxiliary heating.

[0034] Furthermore, in step (4), the stirring time is 1~5 min and the speed is 100~200 rpm.

[0035] Furthermore, this invention releases the molten electrolyte trapped between alloy particles through stirring, and utilizes the density difference between the molten electrolyte and the magnesium-rare earth alloy liquid to achieve static stratification within the feeding container. During the stirring process, the composition of magnesium and rare earth elements is simultaneously homogenized, reducing potential localized component segregation during electrolysis.

[0036] Furthermore, the stirring tool mentioned in step (4) is made of graphite, tungsten, molybdenum, or high-temperature resistant ceramic materials. The stirring tool is used to promote the aggregation of the fish roe-like alloy and the homogenization of the alloy composition.

[0037] Furthermore, the stirring in step (4) can at least break the salt film or oxide film on the surface of the fish roe-shaped magnesium rare earth intermediate alloy particles, promote the fusion of dispersed particles, and aggregate them into a continuous metal phase.

[0038] Furthermore, the settling time in step (5) is 5~10 minutes.

[0039] Furthermore, this invention achieves efficient separation of magnesium rare earth alloys and molten salt by draining the residual electrolyte after stratification through methods such as pouring, scraping, or diversion.

[0040] Furthermore, the magnesium rare earth master alloy includes Mg-La, Mg-Ce, or Mg-Sc.

[0041] Furthermore, the above method can complete material extraction and online refining while the electrolytic cell is running continuously, reducing or avoiding process separation and secondary remelting caused by subsequent refining.

[0042] In some preferred embodiments, a schematic flow chart of the online refining and homogenization method for preparing magnesium rare earth master alloys by molten salt electrolytic co-deposition in this invention is shown below. Figure 1 As shown.

[0043] In some preferred embodiments, the online refining and homogenization method for preparing magnesium rare earth master alloys by molten salt electrolytic co-deposition includes:

[0044] Step 1: Preheat the material handling container

[0045] The material receiving container is preheated to a temperature range in which the alloy can remain in a molten or semi-molten state, preferably 700-800°C, and the specific temperature is determined according to the composition of the magnesium rare earth alloy.

[0046] Step 2: Material Retrieval

[0047] During electrolysis or when discharging the electrolytic material, the fish roe-like magnesium rare earth alloy is removed from the bottom of the electrolytic cell, the cathode area, or the alloy collection area using a preheated collection container. A small amount of molten electrolyte is allowed to be trapped between the alloy particles during collection.

[0048] Step 3: Insulation

[0049] The container containing the fish roe-like alloy is placed in an insulated position. The material inside the container is kept in a molten or semi-molten state by utilizing the container's insulation structure, the alloy's own residual heat, or auxiliary heating.

[0050] Step 4: Stirring and Gathering

[0051] The fish roe-like alloy is stirred using a stirring tool for a preferred stirring time of 1 to 5 minutes.

[0052] During stirring, the salt film or oxide film on the surface of the alloy particles is destroyed, and the dispersed metal particles come into contact with each other and fuse, gradually forming a plate-like, blocky, or continuous metal phase; at the same time, the molten electrolyte trapped between the particles is gradually released and forms an independent liquid phase. In addition, the flow and convection generated by stirring can promote the diffusion of magnesium and rare earth elements, improving the uniformity of the alloy composition.

[0053] Step 5: Allow to stand and separate into layers

[0054] After stopping stirring, continue to keep warm and let stand for 5 to 10 minutes, so that the residual molten electrolyte and magnesium rare earth alloy will separate into layers due to differences in density and wettability.

[0055] Normally, the less dense molten electrolyte floats to the top of the container, while the denser magnesium rare earth alloy liquid sinks and accumulates at the bottom of the container, forming sheet-like, blocky, or continuous metallic phases.

[0056] Step Six: Eliminate Electrolytes

[0057] Slowly tilt the feeding container to pour the stratified residual molten electrolyte back into the electrolytic cell or discharge it into the waste salt collection container, while retaining the aggregated magnesium rare earth alloy.

[0058] Step 7: Casting or Transfer

[0059] The magnesium rare earth alloy, after online refining and homogenization, is poured into a preheated mold to cool and solidify, or transferred to an intermediate ladle or ingot mold for later use.

[0060] When implementing the method of this invention, a high-temperature resistant feeding spoon, crucible, or other molten salt corrosion-resistant container can be used as the online refining container. The feeding container is made of a material that is resistant to high temperatures and molten salt corrosion and does not readily react with magnesium rare earth alloys; stainless steel, nickel-plated steel, graphite-lined metal containers, or ceramic-lined metal containers are suitable options. The inner wall of the container preferably has a smooth, rounded structure to reduce alloy adhesion and facilitate metal phase aggregation and electrolyte stratification.

[0061] An insulation layer may be provided on the outside of the material receiving container. The insulation layer may be made of ceramic fiber felt, aluminum silicate cotton or other high-temperature resistant insulation materials to reduce heat loss and maintain the alloy inside the container in a molten or semi-molten state.

[0062] The inner wall of the container may also be provided with an isolation coating. The isolation coating may be made of boron nitride, yttrium oxide or other high-temperature resistant materials that do not easily react with magnesium rare earth alloys, so as to reduce the phenomenon of alloy sticking to the wall.

[0063] When implementing the method of this invention, a stirring tool can also be used. The stirring tool can be a graphite rod, tungsten rod, molybdenum rod, or high-temperature resistant ceramic rod, used to stir the fish roe-like alloy, promoting particle aggregation and composition homogenization. If necessary, the material receiving container can also be equipped with an auxiliary heating device to preheat the container or supplement heat during processing, preventing rapid solidification of the alloy.

[0064] The containers, stirring tools, and heating devices described above are all auxiliary structures for implementing the method of the present invention and do not limit the scope of protection of the present invention.

[0065] This invention utilizes the characteristic that the fish roe-like alloy extracted from the electrolytic cell is still in a high-temperature state, and performs real-time online processing before it completely solidifies. By maintaining the temperature, the metal phase and molten electrolyte remain fluid; by stirring, the fish roe-like alloy particles collide and rub against each other, breaking down the salt film or oxide film on the particle surface, allowing fresh metal to come into contact and fuse; by allowing it to stand, the molten electrolyte and alloy phase separate under gravity; and by tilting or scraping, residual electrolyte is removed, thereby achieving online salt removal, refining, and homogenization of the alloy.

[0066] Compared with traditional offline remelting and refining, this invention does not require cooling and remelting the fish roe-like alloy, nor does it require setting up independent and complex refining equipment. It can complete alloy aggregation, molten salt separation and composition homogenization during the material collection process. It has the advantages of short process, low energy consumption, simple operation, less rare earth burning loss and suitability for laboratory and pilot production applications.

[0067] The method provided by this invention utilizes the characteristic that the fish roe-like alloy taken from the bottom of the electrolytic cell is still in a high temperature state. It directly performs heat preservation, stirring and static stratification treatment in the material scoop, so that the dispersed metal particles aggregate into a continuous alloy phase. At the same time, it realizes the separation of residual molten salt electrolyte from the metal phase, thereby reducing salt inclusion, reducing secondary remelting energy consumption, reducing rare earth element oxidation loss, and improving alloy yield and composition uniformity.

[0068] The technical solution of the present invention will be further described in detail below with reference to several preferred embodiments and accompanying drawings. This embodiment is implemented on the premise of the technical solution of the invention, and provides detailed implementation methods and specific operation processes. However, the protection scope of the present invention is not limited to the following embodiments.

[0069] Unless otherwise specified, the experimental materials used in the examples below can be purchased from conventional biochemical reagent companies.

[0070] Example 1

[0071] An online refining and homogenization method for preparing magnesium-rare earth master alloys by molten salt electrolytic co-deposition is disclosed. This embodiment is used to prepare magnesium-lanthanum master alloys. The electrolyte system is 10 wt.% MgCl2-25 wt.% LaCl3-65 wt.% KCl, and electrolysis is performed using a graphite anode and a tungsten cathode at an electrolysis temperature of approximately 880℃ and an electrode spacing of approximately 5 cm. During electrolysis, a fish-roe-like Mg-La alloy and a small amount of entrained molten electrolyte are taken from the bottom of the electrolytic cell or the cathode area and placed in a preheated high-temperature resistant collection container. The inner wall of the collection container is coated with a boron nitride insulating layer, and the outside is equipped with a heat insulation layer. After collection, the material is kept in a molten or semi-molten state by utilizing the residual heat of the alloy itself and the heat insulation effect of the collection container. Subsequently, the fish-roe-like alloy is stirred with a graphite stirring rod for about 2 minutes to allow the dispersed alloy particles to collide and fuse with each other, and to release the molten electrolyte entrained between the particles. After stopping stirring, the mixture is allowed to stand for about 1 minute to allow the Mg-La alloy and the residual molten electrolyte to separate into layers. The material receiving container was then tilted to pour out the residual electrolyte, retaining the Mg-La alloy liquid that had aggregated into flakes, which was then cast into shape. In this embodiment, the magnesium-lanthanum master alloy contained approximately 41%–42% La and approximately 58%–59% Mg. The alloy aggregated from fish roe-like particles into relatively complete alloy blocks or flakes, with a significant reduction in salt inclusions. A comparison of the magnesium rare earth master alloy states before and after refining and homogenization treatments in this embodiment is shown in the figure below. Figure 2 and Figure 3 As shown, Figure 2 The alloy produced by electrolysis is in an untreated state, and the alloy is in the form of fish roe, granules or loose dispersion. The metal phase has not been effectively aggregated and contains residual molten electrolyte. Figure 3 The alloy state after online refining and homogenization is as follows: after heat preservation, stirring and static stratification, the dispersed alloy particles aggregate into a relatively complete plate-like or blocky metal phase, and the alloy aggregation effect is significantly improved.

[0072] Example 2

[0073] An online refining and homogenization method for preparing magnesium rare earth master alloys by molten salt electrolytic co-deposition is disclosed. This embodiment is used to prepare magnesium-lanthanum master alloys with medium to high rare earth content. The electrolyte system is 10 wt.% MgCl2-25 wt.% LaCl3-65 wt.% KCl, and molten salt electrolysis is performed using a graphite anode and a tungsten cathode, with an average electrolysis current of approximately 3500 A. After a certain amount of fish roe-like Mg-La alloy is generated at the bottom of the electrolytic cell, it is collected using a preheated high-temperature resistant collection container. The collected fish roe-like alloy is not cooled or transferred to a separate refining device for remelting, but is directly subjected to online refining treatment in the collection container. Specifically, after collection, the material is immediately kept at a high temperature and stirred for 1-5 minutes using a high-temperature resistant stirring tool to break the surface salt film of the fish roe-like alloy particles and gradually aggregate them; then it is allowed to stand for 0.5-3 minutes to allow the residual molten electrolyte and Mg-La alloy to separate into layers; finally, the residual molten electrolyte is poured out, and the aggregated alloy liquid is cast into ingots. The alloy obtained in this embodiment weighs approximately 8.2 kg, with a composition of Mg 49.65 wt.% and La 50.35 wt.%, and a current efficiency of approximately 94.81%. After online refining and homogenization, the alloy exhibits good aggregation, facilitating subsequent casting, weighing, and composition analysis.

[0074] Example 3

[0075] An online refining and homogenization method for preparing magnesium rare earth master alloys by molten salt electrolytic co-deposition is disclosed. This embodiment is used to prepare magnesium-lanthanum master alloys with low rare earth content. The electrolyte system is a MgCl2-LaCl3-KCl chloride molten salt system, wherein the LaCl3 content can be adjusted according to the target alloy composition. The electrolysis temperature is controlled at approximately 870°C, and co-deposition electrolysis is performed using a graphite anode and a tungsten cathode. After electrolysis for a certain period of time, a fish roe-like Mg-La alloy containing approximately 25%–30% La is taken out from the bottom of the electrolytic cell. The taken-out alloy is placed in a preheated feeding container at approximately 650°C and kept at a high temperature. Subsequently, it is stirred with a graphite rod or tungsten rod for about 3 minutes to allow the fine dispersed alloy particles to fuse and aggregate, while releasing the entrained molten electrolyte. After stirring, it is allowed to stand for about 1.5 minutes until the residual electrolyte and alloy phases separate. The electrolyte is then poured out to obtain the aggregated Mg-La alloy liquid. After casting, the resulting alloy contains approximately 26.5% La, approximately 73.5% Mg, and approximately 88.0% current efficiency.

[0076] Example 4

[0077] An online refining and homogenization method for preparing magnesium-rare earth master alloys by molten salt electrolytic co-deposition is disclosed. This embodiment is used to prepare magnesium-cerium master alloys. The electrolyte system is a MgCl2-CeCl3-KCl chloride molten salt system, the composition of which can be set as 10wt.%MgCl2-25wt.%RECl3-65wt.%KCl. Molten salt electrolysis is performed using a graphite anode and a tungsten cathode, and the electrolysis temperature is controlled at approximately 860-890℃. During electrolysis, fish roe-like Mg-Ce alloy particles are generated in the cathode region. During material removal, a preheated high-temperature resistant material removal container is used to remove the fish roe-like Mg-Ce alloy and a small amount of entrained molten salt from the bottom of the electrolytic cell or the cathode region. Subsequently, the material is kept at a constant temperature and stirred in the material removal container for approximately 1.5-2.5 minutes to allow the fish roe-like alloy particles to fuse together and release the entrained electrolyte. After stopping stirring, the mixture is allowed to stand for approximately 1-2 minutes to allow the molten electrolyte and Mg-Ce alloy liquid to separate into layers. The residual electrolyte is then poured out by tilting the feeding container, and the aggregated Mg-Ce alloy liquid is cast into shape. In this embodiment, the Ce content in the magnesium-cerium master alloy can be controlled between approximately 25% and 55%, and the current efficiency can reach up to approximately 88%. After processing using this method, the fish-roe-like Mg-Ce alloy can complete aggregation, salt removal, and homogenization during the feeding process, reducing the need for subsequent offline remelting and refining.

[0078] In addition, the applicant also conducted experiments with other raw materials, process operations, and process conditions described in this specification, referring to the aforementioned embodiments, and obtained relatively ideal results in all cases.

[0079] It should be understood that the technical solutions of the present invention are not limited to the specific embodiments described above. Any technical modifications made to the technical solutions of the present invention without departing from the spirit and scope of the claims are within the scope of protection of the present invention.

Claims

1. An online refining and homogenization method for preparing magnesium rare earth master alloys by molten salt electrolytic co-deposition, characterized in that, include: Preheat the material receiving container to the temperature at which the magnesium rare earth intermediate alloy remains in a molten or semi-molten state. Furthermore, during the preparation of magnesium rare earth master alloys by molten salt electrolytic co-deposition or during electrolytic discharge, a preheated material handling container is used to remove the fish roe-like magnesium rare earth master alloy, which is then subjected to heat preservation, stirring, static layering, salt removal, and casting molding processes, thereby achieving online refining and homogenization of magnesium rare earth master alloys prepared by molten salt electrolytic co-deposition.

2. The online refining and homogenization method according to claim 1, characterized in that, Specifically, it includes: (1) Preheat the material receiving container to the temperature at which the magnesium rare earth intermediate alloy remains in a molten or semi-molten state; (2) During the preparation of magnesium rare earth intermediate alloy by molten salt electrolytic co-deposition or during electrolytic discharge, a preheated material collection container is used to take out the fish roe-shaped magnesium rare earth intermediate alloy from the bottom of the electrolytic cell, the cathode area or the alloy collection area; the fish roe-shaped magnesium rare earth intermediate alloy particles contain a small amount of molten electrolyte. (3) Keep the container containing the fish roe-shaped magnesium rare earth intermediate alloy in the electrolysis device to keep the material in the container in a molten or semi-molten state. (4) Use a stirring tool to stir the fish roe-like magnesium rare earth intermediate alloy in the heat-insulated material container; (5) After stopping stirring, continue to keep it warm and stand so that the residual molten electrolyte and magnesium rare earth intermediate alloy separate into layers; (6) The residual molten electrolyte after stratification is poured back into the electrolytic cell or discharged into the waste salt collection container by means of dumping, scraping or diversion, and the magnesium rare earth intermediate alloy after aggregation is collected. (7) Pour the aggregated magnesium rare earth intermediate alloy into a preheated mold to cool and form, or transfer it to an intermediate ladle or ingot mold for later use.

3. The online refining and homogenization method according to claim 2, characterized in that: The temperature at which the molten or semi-molten state is maintained is 700–800°C.

4. The online refining and homogenization method according to claim 2, characterized in that: The material receiving container is provided with a heat insulation layer and an inner wall isolation coating; the inner wall isolation coating includes boron nitride or yttrium oxide.

5. The online refining and homogenization method according to claim 2, characterized in that: In step (3), the material inside the material taking container is kept in a molten or semi-molten state by utilizing the heat insulation structure of the material taking container, the residual heat of the fish roe-shaped magnesium rare earth intermediate alloy itself, or auxiliary heating.

6. The online refining and homogenization method according to claim 2, characterized in that: In step (4), the stirring time is 1~5 min and the speed is 100-200 rpm.

7. The online refining and homogenization method according to claim 2, characterized in that: The material of the stirring tool mentioned in step (4) includes graphite, tungsten, molybdenum or high-temperature resistant ceramic materials.

8. The online refining and homogenization method according to claim 2, characterized in that: The stirring in step (4) can at least break the salt film or oxide film on the surface of the fish roe-shaped magnesium rare earth intermediate alloy particles, promote the fusion of dispersed particles, and aggregate them into a continuous metal phase.

9. The online refining and homogenization method according to claim 2, characterized in that: The settling time in step (5) is 5~10 minutes.

10. The online refining and homogenization method according to claim 2, characterized in that: The magnesium rare earth master alloy includes Mg-La, Mg-Ce, or Mg-Sc.

Images