Preparation device and preparation method of nickel-magnesium intermediate alloy

Abstract

The nickel-magnesium intermediate alloy preparation device comprises a reaction furnace and a cooling furnace which are connected through a reaction furnace vacuumizing pipeline, a reaction crucible is installed in the reaction furnace, a heating device is arranged on the inner wall of the reaction furnace, the bottom of the reaction furnace is connected with an argon inlet, a cooling furnace vacuumizing pipeline is arranged on the cooling furnace, and a cooling liquid cavity is formed in the wall body of the cooling furnace; the preparation method of the alloy comprises the following steps: 1, selecting nickel chloride, magnesium chloride and magnesium granule raw materials and drying; 2, weighing the raw materials and uniformly mixing; and 3, carrying out a molten salt reduction reaction, and cooling and recovering the molten salt. According to the device disclosed by the invention, the reaction furnace and the cooling furnace are arranged, so that the preparation of nickel-magnesium intermediate alloy and the cooling, recycling and reusing of magnesium chloride molten salt are realized; according to the method, argon is introduced after vacuumizing to remove air, oxygen absorption and nitrogen absorption in the molten salt reduction reaction stage are avoided, magnesium and nickel losses are reduced, and the yield of the nickel-magnesium alloy is increased; the nickel-magnesium intermediate alloy prepared through the method is uniform in component and high in purity, and can be used as an additive raw material for high-temperature alloy smelting.

Description

Technical Field

[0001] The present invention belongs to the technical field of alloy preparation, and in particular relates to a device and method for preparing a nickel-magnesium master alloy. Background Art

[0002] Superalloys, due to their exceptional performance, play a key role in high-temperature environments such as aerospace, naval vessels, and industrial gas turbines. They are indispensable materials for hot-end components in modern aircraft engines and aerospace equipment. During the superalloy production process, magnesium is typically added in the form of a nickel-magnesium master alloy, the final step after refining and before the finished product is released from the furnace. Therefore, the quality of the nickel-magnesium master alloy is crucial to the performance and quality of the superalloy. However, the production of nickel-magnesium master alloys faces numerous challenges. Nickel has a high melting point of 1452°C, far higher than that of magnesium (620°C), and magnesium metal has a high vapor pressure and is not easily resistant to induction heating. These characteristics lead to the generation of large amounts of smoke and even explosions during the production process, resulting in low magnesium yields. Furthermore, achieving a uniform distribution of magnesium in the alloy and precisely controlling its content are challenging.

[0003] Patent publication number CN116694957A relates to a nickel-magnesium alloy and its preparation method. This alloy has a magnesium content between 9% and 17%. The preparation process uses high-purity electrolytic nickel and primary magnesium ingots as raw materials. This method involves smelting in an induction melting furnace under a pressurized inert gas shield. In the later stages of smelting, argon gas is blown into the bottom of the equipment to stir the melt, promoting uniformity of the alloy composition. The argon bubbles lift inclusions, thereby improving the alloy's purity. During the pouring process, a chute made of high-magnesium refractory material and equipped with a magnesium-based ceramic foam filter further purifies the alloy. Finally, the alloy is rapidly solidified in a water-cooled crystallizer. This preparation method produces a nickel-magnesium alloy with uniform composition and high purity. However, this process places high demands on equipment, requiring bottom argon blowing during smelting and inclusion removal using a chute and ceramic foam during the pouring phase. The overall process is complex, and pre-smelting equipment preparation is relatively tedious.

[0004] Patent publication number CN112593102A discloses a method for preparing a nickel-magnesium hydrogen storage alloy with a magnesium content of 75% to 78%. The preparation process involves heating dried magnesium ingots and nickel plates in a non-vacuum medium-frequency electromagnetic induction furnace. During the initial heating process, when 60% to 85% of the magnesium ingot begins to melt, SF6 and N2 are introduced until all the magnesium ingot is completely melted, after which the nickel plates are added. After the nickel plates are completely melted and the melt is stirred, the remaining magnesium ingots are added to lower the melt temperature. Finally, the nickel-magnesium master alloy is produced by casting. This method requires relatively low equipment requirements and a relatively simple production process. However, the prolonged introduction of SF6 and N2 during the non-vacuum melting process is notable. SF6 is a potent greenhouse gas with a carbon emission equivalent coefficient as high as 23,900 and a half-life of 3,200 years. It is one of the six greenhouse gases restricted by international conventions. From a sustainable development perspective, this method has significant shortcomings, and future research is needed to explore more environmentally friendly methods for producing nickel-magnesium master alloys.

[0005] The invention patent with patent publication number CN100473734A relates to a method for smelting a nickel-magnesium alloy with a magnesium content between 8% and 49%. The method designs four ways of charging raw materials and uses a vacuum coreless induction furnace for smelting. The lining of the smelting furnace is made of magnesia. After the metal raw materials are added to the furnace, a pre-slag melt containing mainly NaCl and KCl is added; during the smelting process, at least two manual furnace shaking operations are required, and argon gas is introduced for protection after the charge is melted; finally, the alloy is poured into a refractory ingot mold to complete the preparation. However, this method has some shortcomings. First, the method for handling the pre-melted slag during the production process is not clearly explained, which may bring uncertainty to the actual operation. Second, the material of the smelting furnace lining and the casting ingot mold are both refractory, which may lead to the inevitable appearance of inclusions introduced by the refractory in the alloy, thereby affecting the purity and performance of the alloy. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to address the shortcomings of the above-mentioned prior art and provide a device for preparing a nickel-magnesium master alloy. The device comprises a connected reaction furnace and a cooling furnace. A heating device is installed in the lining of the reaction furnace to slowly heat and stimulate the molten salt reduction reaction. A coolant cavity is provided in the cooling furnace wall to ensure cooling and recovery. This device achieves the preparation of the nickel-magnesium master alloy and the cooling, recovery, and reuse of the magnesium chloride molten salt, thereby improving the compositional uniformity and purity of the nickel-magnesium master alloy. This device solves the technical difficulties of existing nickel-magnesium alloy preparation methods, such as high equipment requirements, complex and cumbersome processes, poor environmental performance, and poor purity and compositional uniformity of the nickel-magnesium master alloy.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is: a nickel-magnesium intermediate alloy preparation device, characterized in that it includes a reactor and a cooling furnace connected by a reactor vacuum pipe, and a reactor vacuum valve is provided at one end of the vacuum pipe close to the reactor, a reaction crucible for holding reaction materials is installed in the reactor, an inner lining is laid on the inner wall of the reactor, a heating device is provided inside the lining, an argon inlet is connected to the bottom, an explosion relief valve is provided on the furnace cover of the reactor, the inner cavity of the cooling furnace is used to hold recovered molten salt, a cooling furnace vacuum pipe is provided on the furnace cover of the cooling furnace, a coolant cavity is provided on the wall of the cooling furnace, and a coolant inlet and a coolant outlet are respectively provided at the bottom and the upper part of the coolant cavity.

[0008] The above-mentioned nickel-magnesium master alloy preparation device is characterized in that the material of the lining is corundum brick.

[0009] The above-mentioned nickel-magnesium master alloy preparation device is characterized in that the coolant cavity is a double-layer water-cooling jacket structure.

[0010] At the same time, the present invention also discloses a method for preparing a nickel-magnesium master alloy using the above-mentioned device, characterized in that the method comprises the following steps: Step 1: Material preparation and drying: nickel chloride, magnesium chloride and magnesium particles are selected as raw materials, and placed in a hot air circulation drying furnace for drying; Step 2: Weighing and mixing materials: According to the composition of the target product nickel-magnesium master alloy, weigh the raw materials dried and prepared in step 1 and mix them evenly to obtain a mixed raw material; Step 3, molten salt reduction reaction and molten salt cooling and recovery: the mixed raw materials in step 2 are placed in a reaction crucible as a reaction material, and then the reaction furnace vacuum pipe and the cooling furnace vacuum pipe are used to evacuate the reaction furnace and the cooling furnace, and then argon is continuously introduced through the argon inlet, and then heated by a heating device to cause the reaction material to undergo a molten salt reduction reaction to form a melt. During the reaction, the vaporized magnesium chloride molten salt enters the cooling furnace under the drive of the introduced argon gas, and the coolant is continuously introduced into the coolant cavity through the coolant inlet and flows out through the coolant outlet, thereby cooling and recovering the vaporized magnesium chloride molten salt in the cooling furnace to obtain a recovered molten salt, which is taken out after the molten salt reduction reaction is completed and the melt is cooled to obtain a nickel-magnesium intermediate alloy ingot.

[0011] The above method is characterized in that the nickel chloride described in step 1 meets the specifications and composition requirements of GB / T 15355-2008, "Chemical Reagent Nickel Chloride Hexahydrate," the magnesium chloride meets the specifications and composition requirements of GB / T 672-2006, "Chemical Reagent Magnesium Chloride Hexahydrate," the magnesium particles have a diameter of 3 mm, and the composition meets the requirement of Mg9995 in GB / T3499-2023, "Native Magnesium Ingot." The present invention ensures the accuracy of the composition of the resulting nickel-magnesium master alloy by strictly controlling the content of impurity elements in the raw materials used to prepare the nickel-magnesium master alloy.

[0012] The above method is characterized in that the drying temperature in step 1 is 180°C to 200°C and the drying time is 6 hours to 8 hours. The present invention removes any water vapor that may be present in the reaction materials by drying the reaction materials in advance, thereby avoiding sputtering caused by water vapor during the reduction reaction.

[0013] The above method is characterized in that the composition of the raw materials weighed and dried in step 2 is, by weight, 25.3 to 31.0 parts nickel chloride, 50.6 to 62.0 parts magnesium chloride, and 7.1 to 24.1 parts magnesium particles. The present invention ensures that the chemical composition of the nickel-magnesium master alloy reaches the target range by strictly controlling the ratio of the reaction raw materials.

[0014] The above method is characterized in that the mixing in step 2 is carried out using a mixer at a rotation speed of 40 rpm to 80 rpm and a mixing time of 20 to 30 minutes. The present invention controls the rotation speed and mixing time to obtain a uniform mixture of raw materials, avoid element segregation in the prepared alloy, and ensure the compositional uniformity of the nickel-magnesium master alloy.

[0015] The above method is characterized in that the argon gas flow rate in step 3 is 100 L / min, the heating rate is 15°C / min, the temperature is raised to 800°C and maintained for 1 hour. The present invention promotes the molten salt reduction reaction by controlling the heating rate, temperature, and time, ensuring complete reaction of the raw materials, and facilitating the production of a uniform nickel-magnesium alloy from the reduced nickel and excess magnesium in a molten state. The above method is characterized in that in step 3, the melt in the reaction crucible is taken out after solidification and cooling to a temperature below 500° C., the nickel-magnesium master alloy ingot is separated from the slag, and the nickel-magnesium master alloy ingot is refined, screened, inspected, and packaged. Compared with the prior art, the present invention has the following advantages: 1. The nickel-magnesium master alloy preparation device of the present invention sets a reaction furnace and a cooling furnace as the molten salt reduction reaction and molten salt cooling and recovery sites respectively, and sets a heating device in the lining of the reaction furnace to slowly heat and stimulate the molten salt reduction reaction. A coolant cavity is set on the cooling furnace wall to ensure the cooling and recovery effect, thereby realizing the preparation of the nickel-magnesium master alloy and the cooling, recovery and reuse of the magnesium chloride molten salt, and improving the composition uniformity and purity of the nickel-magnesium master alloy.

[0016] 2. The nickel-magnesium master alloy preparation device of the present invention provides a reaction furnace vacuum pipe between the reaction furnace and the cooling furnace, provides a cooling furnace vacuum pipe on the furnace cover of the cooling furnace, and connects an argon inlet at the bottom of the reaction furnace to vacuum the reaction furnace and the cooling furnace to remove the air in the furnace and continuously introduce argon gas, thereby providing an inert gas atmosphere for the molten salt reduction reaction, avoiding oxygen and nitrogen absorption during the molten salt reduction reaction stage, and avoiding moisture absorption and hydrolysis of the raw material NiCl2, thereby further improving the purity and yield of the nickel-magnesium master alloy.

[0017] 3. The preparation method of the present invention selects nickel chloride, magnesium chloride and magnesium particles as raw materials, performs a molten salt reduction reaction under the conditions of a molten salt medium formed by melting nickel chloride and magnesium chloride, promotes the reduction of nickel chloride by magnesium, and enables the nickel reduced by magnesium to form a nickel-magnesium intermediate alloy with uniform composition and high purity with excess magnesium in a molten state. At the same time, the magnesium chloride generated by the molten salt reduction reaction is cooled, recovered and reused, thereby realizing resource utilization and avoiding waste.

[0018] 4. Compared with the smelting method for preparing nickel-magnesium alloy, the present invention adopts molten salt reduction reaction to prepare nickel-magnesium intermediate alloy under the protection of argon atmosphere, which effectively prevents the oxidation or combustion of magnesium at high temperature, and avoids the moisture absorption and hydrolysis of NiCl2, reduces the loss of magnesium and nickel, and improves the yield of nickel-magnesium alloy.

[0019] 5. The nickel-magnesium master alloy prepared by the present invention has the characteristics of uniform alloy composition and high purity. It can be used as a smelting additive material for high-temperature alloys, reducing the burn-off of the low-melting-point element magnesium, and obtaining a high-temperature alloy product with more uniform composition and superior performance.

[0020] 6. The method for preparing the nickel-magnesium master alloy of the present invention is simple and applicable. The prepared nickel-magnesium alloy has high purity and uniform composition. The composition of the nickel-magnesium alloy product can be customized according to demand, and is suitable for large-scale and mass industrial production.

[0021] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic structural diagram of the device for preparing nickel-magnesium master alloy according to the present invention.

[0023] Figure 2 This is a SEM scan of the nickel-magnesium master alloy ingot prepared in Example 2 of the present invention.

[0024] Figure 3 This is the distribution diagram of Ni element in the nickel-magnesium master alloy ingot prepared in Example 2 of the present invention.

[0025] Figure 4 This is the distribution diagram of Mg element in the nickel-magnesium master alloy ingot prepared in Example 2 of the present invention.

[0026] Description of Reference Numerals DETAILED DESCRIPTION

[0027] The nickel-magnesium master alloy preparation device of the present invention is described in detail through Example 1.

[0028] Example 1 like Figure 1 As shown, the nickel-magnesium master alloy preparation device of this embodiment includes a reactor 3 and a cooling furnace 13 connected by a reactor vacuum pipe 10, and a reactor vacuum valve 1 is provided at one end of the vacuum pipe 10 close to the reactor 3, a reaction crucible 6 for holding a reaction material 7 is installed in the reactor 3, an inner wall of the reactor 3 is paved with an inner lining 4, a heating device 5 is provided inside the inner lining 4, an argon inlet 8 is connected to the bottom, an explosion relief valve 2 is provided on the furnace cover of the reactor 3, the inner cavity of the cooling furnace 13 is used to hold the recovered molten salt 15, a cooling furnace vacuum pipe 11 is provided on the furnace cover of the cooling furnace 13, a coolant cavity 14 is provided on the wall of the cooling furnace 13, and a coolant inlet 9 and a coolant outlet 12 are respectively provided at the bottom and the upper part of the coolant cavity 14.

[0029] In the nickel-magnesium master alloy preparation device of this embodiment, a reaction furnace 3 and a cooling furnace 13 are provided. The reaction furnace 3 is used as a place for preparing the nickel-magnesium master alloy by the molten salt reduction reaction, and the cooling furnace 13 is used as a place for cooling and recovering the molten magnesium chloride escaped in the molten salt reduction reaction. The reaction furnace vacuum pipe 10 is provided to connect the reaction furnace 3 and the cooling furnace 13 to ensure connectivity between the two. On the one hand, it is convenient to vacuum the reaction furnace 3 and introduce argon gas. On the other hand, it provides a channel for the gaseous magnesium chloride molten salt escaped from the reaction furnace 3 to enter the cooling furnace 13. At the same time, a reaction furnace vacuum valve 1 is provided at one end of the vacuum pipe 10 close to the reaction furnace 3 to control the connection and closing between the reaction furnace 3 and the cooling furnace 13, thereby ensuring the independence and connectivity of the reaction furnace 3 and the cooling furnace 13, so that the molten salt reduction reaction and the cooling and recovery of the molten salt are carried out separately without affecting each other.

[0030] In the nickel-magnesium master alloy preparation device of this embodiment, a reaction crucible 6 is installed in the reactor 3 for holding the reaction material 7 of the molten salt reduction reaction. A lining 4 is laid on the inner wall of the reactor 3, and a heating device 5 is provided inside the lining 4. The slow heating and temperature increase effect of the heating device 5 is utilized to stimulate the reaction material 7 to undergo a molten salt reduction reaction. Combined with the heat preservation effect of the lining 4, heat loss is avoided, thereby promoting the homogenization of the composition of the nickel-magnesium master alloy generated by the reaction. In addition, an argon inlet 8 is connected to the bottom of the reactor 3 for continuously introducing argon gas to provide an inert gas atmosphere for the molten salt reduction reaction, thereby avoiding oxygen and nitrogen absorption during the molten salt reduction reaction stage, and facilitating the improvement of the purity of the nickel-magnesium master alloy. An explosion relief valve 2 is provided on the furnace cover of the reactor 3 to prevent an explosion in the reactor 3 due to excessive pressure.

[0031] In the nickel-magnesium master alloy preparation apparatus of this embodiment, the inner cavity of the cooling furnace 13 can be used to hold the recovered molten salt 15 formed by cooling and recovering the gaseous magnesium chloride molten salt escaping from the reaction furnace 3. By providing a cooling furnace vacuum pipe 11 on the furnace cover of the cooling furnace 13, the cooling furnace 13 is easily vacuumed to prevent residual oxygen and nitrogen from affecting the purity of the recovered molten salt 15. A coolant cavity 14 is provided on the wall of the cooling furnace 13, and a coolant inlet 9 and a coolant outlet 12 are respectively provided at the bottom and top of the coolant cavity 14, so that a coolant (such as water) enters the coolant cavity 14 through the coolant inlet 9 and circulates out through the coolant outlet 12, thereby cooling the cooling furnace 13, causing the gaseous magnesium chloride molten salt escaping from the reaction furnace 3 and entering the cooling furnace 13 to condense, thereby achieving cooling and recovery of the magnesium chloride molten salt.

[0032] Furthermore, the material of the lining 4 is corundum brick. Corundum brick has good high temperature resistance, high strength and hardness. Used as a lining can ensure the normal progress of the high temperature molten salt reduction reaction, reduce the risk of damage and extend the service life of the preparation device.

[0033] Furthermore, the cooling liquid cavity 14 is a double-layer water-cooling jacket structure.

[0034] The method for preparing the nickel-magnesium master alloy of the present invention is described in detail through Examples 2 to 4.

[0035] Example 2 The nickel-magnesium master alloy of this embodiment is composed of the following elements in percentage by mass: 15% Mg, the balance being Ni and other impurity elements. The preparation method of the nickel-magnesium master alloy comprises the following steps: Step 1, material preparation and drying: nickel chloride, magnesium chloride and magnesium particles are selected as raw materials, and placed in a hot air circulation drying furnace and dried at 180°C for 8 hours for use; the nickel chloride meets the specifications and composition requirements of GB / T 15355-2008 "Chemical Reagent Nickel Chloride Hexahydrate", the magnesium chloride meets the specifications and composition requirements of GB / T 672-2006 "Chemical Reagent Magnesium Chloride Hexahydrate", the magnesium particles have a diameter of 3 mm, and the composition meets the requirements of Mg9995 in GB / T3499-2023 "Native Magnesium Ingot"; Step 2, weighing and mixing materials: According to the composition of the target product nickel-magnesium master alloy, weigh the raw materials dried and reserved in step 1 in parts by mass: 30.90 parts of nickel chloride, 61.8 parts of magnesium chloride, and 7.3 parts of magnesium particles, and pour them into a mixer and mix them evenly. The speed used is 40r / min and the mixing time is 30min to obtain a mixed raw material; Step 3, molten salt reduction reaction and molten salt cooling recovery: put the mixed raw materials in step 2 into the graphite reaction crucible 6 as the reaction material 7, and then use the reaction furnace vacuum pipe 10 and the cooling furnace vacuum pipe 11 to evacuate the reaction furnace 3 and the cooling furnace 13, and then continuously introduce argon gas with a flow rate of 100L / min through the argon inlet 8, and then use the heating device 5 to heat the reaction at a rate of 15℃ / min, heat to 800℃ and keep warm for 1h, so that the reaction material 7 undergoes a molten salt reduction reaction to form a melt, and the reaction During the process, the vaporized magnesium chloride molten salt enters the cooling furnace 13 under the drive of the introduction of argon gas, and the coolant is continuously introduced into the coolant cavity 14 through the coolant inlet 9 and flows out through the coolant outlet 12, thereby cooling and recovering the vaporized magnesium chloride molten salt in the cooling furnace 13 to obtain a recovered molten salt 15. After the molten salt reduction reaction is completed and the melt in the reaction crucible 6 is solidified and cooled to a temperature below 500°C, it is taken out, and the nickel-magnesium master alloy ingot is separated from the slag to obtain a nickel-magnesium master alloy ingot, and the nickel-magnesium master alloy ingot is refined, screened, inspected, and packaged.

[0036] The composition of the nickel-magnesium master alloy ingot prepared in this example was tested, and the results are shown in Table 1.

[0037] Table 1 Chemical composition (wt.%) of the nickel-magnesium master alloy ingot prepared in Example 2 of the present invention

[0038] As can be seen from Table 1, the nickel-magnesium master alloy ingot contains very low levels of impurity elements, especially oxygen and nitrogen, which avoids affecting the cleanliness of downstream high-temperature alloys.

[0039] Figure 2 This is a SEM scan of the nickel-magnesium master alloy ingot prepared in this embodiment. Figure 3 This is the distribution diagram of Ni element in the nickel-magnesium master alloy ingot prepared in this embodiment. Figure 4 The distribution diagram of Mg element in the nickel-magnesium master alloy ingot prepared in this embodiment is shown in FIG. Figures 2 to 4 It can be seen that the nickel and magnesium elements in the nickel-magnesium master alloy ingot prepared in this embodiment are uniformly distributed overall, no inclusions are found, and no segregation phenomenon exists.

[0040] Example 3 The nickel-magnesium master alloy of this embodiment is composed of the following elements in percentage by mass: 60% Mg, the balance being Ni and other impurity elements. The preparation method of the nickel-magnesium master alloy comprises the following steps: Step 1, material preparation and drying: nickel chloride, magnesium chloride and magnesium particles are selected as raw materials, and placed in a hot air circulation drying furnace and dried at 200°C for 8 hours for standby use; the nickel chloride meets the specifications and composition requirements of GB / T 15355-2008 "Chemical Reagent Nickel Chloride Hexahydrate", the magnesium chloride meets the specifications and composition requirements of GB / T 672-2006 "Chemical Reagent Magnesium Chloride Hexahydrate", the magnesium particles have a diameter of 3 mm, and the composition meets the requirements of Mg9995 in GB / T3499-2023 "Native Magnesium Ingot"; Step 2, weighing and mixing materials: According to the composition of the target product nickel-magnesium master alloy, weigh the raw materials dried and reserved in step 1 in parts by mass: 25.3 parts of nickel chloride, 50.6 parts of magnesium chloride, and 24.1 parts of magnesium particles, and pour them into a mixer and mix them evenly. The speed used is 60r / min and the mixing time is 30min to obtain a mixed raw material; Step 3, molten salt reduction reaction and molten salt cooling recovery: put the mixed raw materials in step 2 into the graphite reaction crucible 6 as the reaction material 7, and then use the reaction furnace vacuum pipe 10 and the cooling furnace vacuum pipe 11 to evacuate the reaction furnace 3 and the cooling furnace 13, and then continuously introduce argon gas with a flow rate of 100L / min through the argon inlet 8, and then use the heating device 5 to heat the reaction at a rate of 15℃ / min, heat to 800℃ and keep warm for 1h, so that the reaction material 7 undergoes a molten salt reduction reaction to form a melt, and the reaction During the process, the vaporized magnesium chloride molten salt enters the cooling furnace 13 under the drive of the introduction of argon gas, and the coolant is continuously introduced into the coolant cavity 14 through the coolant inlet 9 and flows out through the coolant outlet 12, thereby cooling and recovering the vaporized magnesium chloride molten salt in the cooling furnace 13 to obtain a recovered molten salt 15. After the molten salt reduction reaction is completed and the melt in the reaction crucible 6 is solidified and cooled to a temperature below 500°C, it is taken out, and the nickel-magnesium master alloy ingot is separated from the slag to obtain a nickel-magnesium master alloy ingot, and the nickel-magnesium master alloy ingot is refined, screened, inspected, and packaged.

[0041] The composition of the nickel-magnesium master alloy ingot prepared in this example was tested, and the results are shown in Table 2.

[0042] Table 2 Chemical composition (wt.%) of the nickel-magnesium master alloy ingot prepared in Example 3 of the present invention

[0043] As can be seen from Table 2, the nickel-magnesium master alloy ingot contains very low levels of impurity elements, especially oxygen and nitrogen, which avoids affecting the cleanliness of downstream high-temperature alloys.

[0044] Example 4 The nickel-magnesium master alloy of this embodiment is composed of the following elements in mass percentage: Mg 4%, the balance being Ni and other impurity elements. The preparation method of the nickel-magnesium master alloy comprises the following steps: Step 1, material preparation and drying: nickel chloride, magnesium chloride and magnesium particles are selected as raw materials, and placed in a hot air circulation drying furnace and dried at 200°C for 6 hours for standby use; the nickel chloride meets the specifications and composition requirements of GB / T 15355-2008 "Chemical Reagent Nickel Chloride Hexahydrate", the magnesium chloride meets the specifications and composition requirements of GB / T 672-2006 "Chemical Reagent Magnesium Chloride Hexahydrate", the magnesium particles have a diameter of 3 mm, and the composition meets the requirements of Mg9995 in GB / T3499-2023 "Native Magnesium Ingot"; Step 2, weighing and mixing materials: According to the composition of the target product nickel-magnesium master alloy, weigh the raw materials dried and reserved in step 1 in parts by mass: 31.0 parts of nickel chloride, 62.0 parts of magnesium chloride, and 7.1 parts of magnesium particles, and pour them into a mixer and mix them evenly. The speed used is 80r / min and the mixing time is 20min to obtain a mixed raw material; Step 3, molten salt reduction reaction and molten salt cooling recovery: put the mixed raw materials in step 2 into the graphite reaction crucible 6 as the reaction material 7, and then use the reaction furnace vacuum pipe 10 and the cooling furnace vacuum pipe 11 to evacuate the reaction furnace 3 and the cooling furnace 13, and then continuously introduce argon gas with a flow rate of 100L / min through the argon inlet 8, and then use the heating device 5 to heat the reaction at a rate of 15℃ / min, heat to 800℃ and keep warm for 1h, so that the reaction material 7 undergoes a molten salt reduction reaction to form a melt, and the reaction During the process, the vaporized magnesium chloride molten salt enters the cooling furnace 13 under the drive of the introduction of argon gas, and the coolant is continuously introduced into the coolant cavity 14 through the coolant inlet 9 and flows out through the coolant outlet 12, thereby cooling and recovering the vaporized magnesium chloride molten salt in the cooling furnace 13 to obtain a recovered molten salt 15. After the molten salt reduction reaction is completed and the melt in the reaction crucible 6 is solidified and cooled to a temperature below 500°C, it is taken out, and the nickel-magnesium master alloy ingot is separated from the slag to obtain a nickel-magnesium master alloy ingot, and the nickel-magnesium master alloy ingot is refined, screened, inspected, and packaged.

[0045] The composition of the nickel-magnesium master alloy ingot prepared in this example was tested, and the results are shown in Table 3.

[0046] Table 3 Chemical composition (wt.%) of the nickel-magnesium master alloy ingot prepared in Example 4 of the present invention

[0047] As can be seen from Table 3, the nickel-magnesium master alloy ingot contains very low levels of impurity elements, especially oxygen and nitrogen, which avoids affecting the cleanliness of downstream high-temperature alloys.

[0048] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent variation made to the above embodiment based on the essence of the invention technology shall still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A device for preparing nickel-magnesium master alloy, characterized in that: The invention comprises a reactor (3) and a cooling furnace (13) connected by a reactor vacuum pipe (10), wherein a reactor vacuum valve (1) is provided at one end of the vacuum pipe (10) close to the reactor (3), a reaction crucible (6) for holding a reaction material (7) is installed in the reactor (3), an inner lining (4) is laid on the inner wall of the reactor (3), a heating device (5) is provided inside the inner lining (4), and an argon gas inlet (8) is connected to the bottom, an explosion relief valve (2) is provided on the furnace cover of the reactor (3), an inner cavity of the cooling furnace (13) is used for holding a recovered molten salt (15), a cooling furnace vacuum pipe (11) is provided on the furnace cover of the cooling furnace (13), a cooling liquid cavity (14) is provided on the wall of the cooling furnace (13), and a cooling liquid inlet (9) and a cooling liquid outlet (12) are respectively provided at the bottom and the upper part of the cooling liquid cavity (14).

2. A nickel-magnesium master alloy preparation device according to claim 1, characterized in that: The material of the lining (4) is corundum brick.

3. The device for preparing nickel-magnesium master alloy according to claim 1, characterized in that: The cooling liquid cavity (14) is a double-layer water-cooling jacket structure.

4. A method for preparing a nickel-magnesium master alloy using the apparatus according to any one of claims 1 to 3, characterized in that: The method comprises the following steps: Step 1: Material preparation and drying: nickel chloride, magnesium chloride and magnesium particles are selected as raw materials, and placed in a hot air circulation drying furnace for drying; Step 2: Weighing and mixing materials: According to the composition of the target product nickel-magnesium master alloy, weigh the raw materials dried and prepared in step 1 and mix them evenly to obtain a mixed raw material; Step 3, molten salt reduction reaction and molten salt cooling and recovery: the mixed raw materials in step 2 are placed in a reaction crucible (6) as a reaction material (7), and then the reaction furnace vacuum pipe (10) and the cooling furnace vacuum pipe (11) are used to evacuate the reaction furnace (3) and the cooling furnace (13), and then argon is continuously introduced through the argon inlet (8), and then the heating device (5) is used to heat the reaction material (7) so that the molten salt reduction reaction occurs to form a melt. During the reaction, the vaporized magnesium chloride molten salt enters the cooling furnace (13) under the drive of the introduced argon gas, and the coolant is continuously introduced through the coolant inlet (9) into the coolant cavity (14) and flows out through the coolant outlet (12), thereby cooling and recovering the vaporized magnesium chloride molten salt in the cooling furnace (13) to obtain a recovered molten salt (15). After the molten salt reduction reaction is completed and the melt is cooled, it is taken out to obtain a nickel-magnesium intermediate alloy ingot.

5. The method according to claim 4, characterized in that The nickel chloride described in step 1 meets the specifications and composition requirements of GB / T 15355-2008 "Chemical Reagent Nickel Chloride Hexahydrate", the magnesium chloride meets the specifications and composition requirements of GB / T 672-2006 "Chemical Reagent Magnesium Chloride Hexahydrate", the magnesium particle diameter is 3 mm, and the composition meets the requirements of Mg9995 in GB / T3499-2023 "Native Magnesium Ingot".

6. The method according to claim 4, characterized in that The drying temperature in step 1 is 180°C to 200°C, and the drying time is 6h to 8h.

7. The method according to claim 4, characterized in that The composition of the raw materials weighed and dried for standby use in step 2 is as follows by mass: 25.3-31.0 parts of nickel chloride, 50.6-62.0 parts of magnesium chloride, and 7.1-24.1 parts of magnesium particles.

8. The method according to claim 4, characterized in that The mixing in step 2 is carried out by a mixer with a rotation speed of 40 r / min to 80 r / min and a mixing time of 20 min to 30 min.

9. The method according to claim 4, characterized in that In step 3, the flow rate of the argon gas is 100 L / min, the heating rate is 15°C / min, the temperature is raised to 800°C and kept at this temperature for 1 hour.

10. The method according to claim 4, characterized in that In step 3, the melt in the reaction crucible (6) is solidified and cooled to a temperature below 500° C., and then taken out, the nickel-magnesium master alloy ingot is separated from the slag, and the nickel-magnesium master alloy ingot is refined, screened, inspected, and packaged.

Images