A nickel-magnesium master alloy for high-temperature alloys and its preparation method

Abstract

This invention discloses a nickel-magnesium master alloy for high-temperature alloys and its preparation method. The nickel-magnesium master alloy is composed of the following elemental composition by mass percentage: Mg 4%~50%, with the balance being Ni and unavoidable impurities. The method includes: 1. Selecting electrolytic nickel and magnesium ingots, cutting and grinding them, calculating the batching, and weighing and dispensing them; 2. Charging the raw materials into the crucible of an induction melting furnace for melting to obtain an alloy melt; 3. Starting a steam filtration system to pour the alloy melt into a cast iron ingot mold, and obtaining a nickel-magnesium master alloy ingot after cooling. This invention, by introducing an appropriate amount of inert gas during vacuum induction melting to ensure melting and casting under a slight negative pressure, combined with controlling melting process parameters, reduces the introduction of impurities during melting and casting, while also reducing magnesium element vaporization loss, resulting in a nickel-magnesium master alloy with uniform composition, high cleanliness, and low content of harmful gas elements and inclusions, suitable for downstream high-temperature alloy applications.

Description

Technical Field

[0001] This invention belongs to the field of alloy preparation technology, specifically relating to a nickel-magnesium master alloy for high-temperature alloys and its preparation method. Background Technology

[0002] High-temperature alloys have wide applications in environments requiring materials to withstand high temperatures, and are key hot-end components in modern aero-engines, aerospace equipment, ships, and industrial gas turbines. In the preparation of high-temperature alloys, magnesium is typically added in the final step after refining and before the final product, in the form of a nickel-magnesium master alloy. Therefore, the quality of the nickel-magnesium master alloy directly affects the performance and quality of the high-temperature alloy material. For nickel-magnesium master alloys, because the melting point of nickel (1452℃) is much higher than that of magnesium (620℃), and because metallic magnesium has high vapor pressure and is non-inductive, the production process often involves large amounts of smoke and even explosions. Magnesium yield is low, and controlling the uniformity and accurate content of magnesium in the alloy is very difficult.

[0003] Patent publication number CN116694957A discloses a nickel-magnesium alloy with a Mg content of 9%~17% and its preparation method. This method uses high-grade electrolytic nickel and primary magnesium ingots as raw materials, and melts them in an induction melting furnace under pressurized inert gas protection. In the later stages of melting, argon gas is blown into the bottom of the equipment to stir the melt, promoting alloy homogenization and forming bubbles in the melt that carry inclusions to the surface, thus improving alloy purity. The casting process uses a chute made of high-magnesium refractory material and is equipped with magnesium-based foam ceramic filtration to purify the alloy. Finally, the alloy is rapidly solidified in a water-cooled crystallizer. This preparation method can produce nickel-magnesium alloys with uniform composition and high purity. However, the equipment required is complex, requiring bottom argon blowing during melting and the removal of inclusions from the alloy through a chute and foam ceramic during casting. The process flow is relatively complex, and the equipment preparation work before melting is relatively cumbersome.

[0004] Patent publication number CN112593102A discloses a method for preparing a nickel-magnesium hydrogen storage alloy with a Mg content of 75%~78%. This method involves heating dried magnesium ingots and nickel plates in a non-vacuum medium-frequency electromagnetic induction furnace. Initially, 60%~85% of the magnesium ingots are heated, and SF6 and N2 are introduced during the melting process until the magnesium ingots are completely melted. Then, a nickel plate is added, and after the nickel plate is completely melted and the melt is stirred, the remaining magnesium ingots are added to cool the melt. Finally, the melt is cast to obtain a nickel-magnesium master alloy. While this method has low equipment requirements and a simple production process, the prolonged introduction of SF6 and N2 during the non-vacuum melting process is problematic. SF6 is a strong greenhouse gas with a carbon emission equivalent of 23900 and a half-life of 3200 years. It is one of the six greenhouse gases restricted by international conventions. This method clearly does not conform to the concept of sustainable development, and more environmentally friendly methods should be adopted to produce nickel-magnesium master alloys.

[0005] Patent publication number CN100473734A discloses a method for smelting nickel-magnesium alloys with a Mg content of 8% to 49%. This method designs four raw material charging methods, employs a vacuum coreless induction furnace for melting, and uses a magnesia lining. After the metal raw materials are added to the furnace, a pre-melted slag mainly containing NaCl and KCl is added. During the melting process, the furnace is manually shaken at least twice, and argon gas is introduced for protection after the furnace charge is completely melted. Finally, the alloy is poured into a refractory ingot mold to produce the nickel-magnesium alloy. However, this method does not clearly explain the treatment method for the pre-melted slag during production, and since both the furnace lining and the ingot mold are made of refractory materials, it is difficult to avoid inclusions introduced by the refractory materials in the alloy. Summary of the Invention

[0006] The technical problem to be solved by this invention is to provide a nickel-magnesium master alloy for high-temperature alloys, addressing the shortcomings of the prior art. This method involves introducing an appropriate amount of inert gas during vacuum induction melting to ensure melting and casting under a slight negative pressure. Combined with controlled melting process parameters, this reduces the introduction of impurities during melting and casting, while also minimizing magnesium vaporization loss. The result is a nickel-magnesium master alloy with uniform composition, high cleanliness, and low content of harmful gas elements and inclusions. This solves the problems of complex preparation processes, high equipment requirements, easy introduction of impurities, and poor environmental performance associated with existing nickel-magnesium master alloys.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: a method for preparing a nickel-magnesium master alloy for high-temperature alloys, wherein the nickel-magnesium master alloy is composed of the following elements by mass percentage: Mg 4%~50%, with the balance being Ni and unavoidable impurities, characterized in that the method includes the following steps:

[0008] Step 1: Select electrolytic nickel and magnesium ingots as raw materials. After cutting and grinding the raw materials, calculate the proportion of nickel-magnesium master alloy for high-temperature alloy of the target product, weigh and package them.

[0009] Step 2: Load the weighed and packaged raw materials from Step 1 into the crucible of the induction melting furnace, evacuate the furnace and heat it with electricity to melt it. After the raw materials turn red, fill them with argon gas. After all the raw materials have melted, reduce the power by 10kW~30kW and continue melting for 5min~10min to obtain the alloy melt in the crucible.

[0010] Step 3: Start the steam filtration system of the induction melting furnace, pour the alloy melt in the crucible from Step 2 into the cast iron ingot mold, and after cooling for 10-12 hours, open the furnace to take a sample to obtain nickel-magnesium master alloy ingots. Then, refine, screen, inspect, and package the nickel-magnesium master alloy ingots.

[0011] The method for preparing a nickel-magnesium master alloy for high-temperature alloys, as described above, is characterized in that the unavoidable impurities include the following elements in mass percentage: Ag≤0.001%, Co≤0.01%, Fe≤0.1%, Mn≤0.05%, Cu≤0.003%, As≤0.002%, Sn≤0.001%, Zn≤0.002%, Si≤0.02%, P≤0.01%, C≤0.05%, S≤0.005%, O≤0.005%, N≤0.007%.

[0012] The above-mentioned method for preparing a nickel-magnesium master alloy for high-temperature alloys is characterized in that the electrolytic nickel in step one conforms to the Ni9999 specification and composition requirements in GB / T 6516-2010 "Electrolytic Nickel", and the magnesium ingot conforms to the Mg9995 composition requirements in GB / T 3499-2003 "Primary Magnesium Ingots".

[0013] This invention further ensures that a nickel-magnesium master alloy with uniform composition and high purity is obtained through vacuum induction melting by strictly controlling the content of impurity elements in the raw materials of nickel-magnesium master alloy.

[0014] The above-mentioned method for preparing a nickel-magnesium master alloy for high-temperature alloys is characterized in that the length, width, and thickness of the magnesium ingot after cutting and grinding in step one are 10cm~15cm, 5cm~10cm, and 3cm~5cm, respectively, and the length, width, and thickness of the electrolytic nickel after cutting and grinding are 3cm~5cm, 3cm~5cm, and 0.5cm~1.5cm, respectively. This invention removes oil and other impurities that may be present on the surface of the raw materials by grinding, ensuring the cleanliness of the raw materials. Controlling the size of the raw materials through cutting promotes vacuum induction melting and shortens the preparation cycle of the nickel-magnesium master alloy.

[0015] The method for preparing a nickel-magnesium master alloy for high-temperature alloys, as described above, is characterized in that the crucible in step two is a molybdenum crucible with a mass purity of 99.95%. This invention uses a molybdenum crucible with a high melting point, which on the one hand can induce heating to promote the melting and mixing of raw materials, and on the other hand avoids impurities introduced during the melting process due to contact between the alloy melt and the melting vessel, thus improving the purity of the nickel-magnesium master alloy.

[0016] The above-mentioned method for preparing a nickel-magnesium master alloy for high-temperature alloys is characterized in that, in step two, the vacuum level is reduced to no more than 5 × 10⁻⁶. -1 Pa. This invention involves evacuating the vacuum to a degree not exceeding 5 × 10⁻⁶ before electric heating and melting. -1 Pa reduces the amount of harmful gaseous elements that may be introduced by residual air in the furnace, which helps to improve the purity of nickel-magnesium master alloys.

[0017] The method for preparing a nickel-magnesium master alloy for high-temperature alloys, as described above, is characterized in that the electric heating melting mode in step two is a stepped electric heating, gradually adjusting and increasing the melting power, and maintaining each power level for 10 to 15 minutes. The stepped electric heating of this invention makes the raw material melting process relatively smooth, avoiding excessively high power leading to rapid temperature rise, and thus avoiding magnesium element vaporization loss.

[0018] The method for preparing a nickel-magnesium master alloy for high-temperature alloys, as described above, is characterized in that, in step two, after the raw material glows red, argon gas is introduced to -0.045 MPa ± 0.005 MPa. In the smelting process of this invention, an appropriate amount of inert gas is introduced into the furnace before the magnesium ingot melts, effectively ensuring that the induction melting process is carried out under a slight negative pressure, effectively reducing the vaporization loss of Mg element during the smelting process, thereby preparing a nickel-magnesium master alloy with uniform composition, high purity, and low content of harmful gas elements and inclusions, providing high-quality raw materials for downstream high-temperature alloy smelting.

[0019] The method for preparing a nickel-magnesium master alloy for high-temperature alloys is characterized in that the steam filtration system in step three includes a condenser tank installed at the furnace body interface of the induction melting furnace, the condenser tank is provided with a stacked water-cooled baffle, and an oil tank filter is installed at the rear end of the condenser tank. To address the issue of reduced furnace visibility due to magnesium vapor formation during smelting caused by magnesium's low melting point, this invention specifically equips the induction melting furnace with a steam filtration system. This system utilizes stacked water-cooled baffles inside a condenser to collect and condense the magnesium vapor volatilized during smelting, and an oil filter at the rear of the condenser to collect residual magnesium vapor. Typically, the steam filtration system is activated before casting the molten alloy, rapidly extracting a large amount of magnesium vapor from the furnace and enabling visualization of the casting process. This allows for more efficient casting of the molten alloy into the cast iron ingot mold while ensuring safe operation, avoiding the use of cumbersome casting guide devices and the potential introduction of impurities, thus improving production efficiency and reducing impurity introduction. Furthermore, because the duration from system activation to casting completion is short, and the system is not continuously activated throughout the entire smelting process, it does not lead to significant loss of magnesium raw materials through vaporization, thus having minimal impact on the composition of the molten alloy and consequently having no effect on the uniformity and accuracy of the final solidified nickel-magnesium master alloy ingot.

[0020] This invention controls the cooling time to ensure that the nickel-magnesium master alloy ingot is cooled before the furnace is opened for sampling, while also allowing the small amount of magnesium vapor remaining in the furnace to fully adhere or precipitate, thus avoiding potential safety hazards from opening the furnace too early.

[0021] Meanwhile, the present invention also discloses a nickel-magnesium master alloy for high-temperature alloys, characterized in that it is prepared by the above-described method.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] 1. Unlike ordinary induction melting processes, the nickel-magnesium master alloy preparation method of the present invention introduces an appropriate amount of inert gas during vacuum induction melting to ensure melting and casting under a slight negative pressure, thereby reducing the vapor pressure of magnesium and inhibiting magnesium evaporation. This allows low-melting-point metallic magnesium and high-melting-point metallic nickel to be prepared into a nickel-magnesium master alloy with a moderate melting point. This avoids the problems of smoke, fire, and even explosion that are easily caused during the melting process due to the low melting point and high vapor pressure of magnesium. At the same time, it is beneficial to improve the yield of magnesium during the melting process.

[0024] 2. This invention uses a high-purity molybdenum crucible as the melting container, which effectively promotes the melting and mixing of raw materials and avoids the introduction of impurities due to contact between the alloy melt and the crucible during the melting process. At the same time, by using a steam filtration system to extract magnesium vapor from the furnace before pouring the alloy melt, the pouring process is visualized, avoiding the introduction of impurities due to contact between the cumbersome pouring and guiding device and the alloy melt. In addition, the preparation method of this invention does not involve slag protection measures, thereby ensuring the cleanliness of the nickel-magnesium master alloy.

[0025] 3. This invention achieves a vacuum level not exceeding 5×10⁻⁶. -1 The process of heating and smelting after Pa effectively reduces the introduction of harmful gaseous elements that may be introduced by residual air in the furnace. By adopting stepped heating, the rapid temperature rise caused by excessive power is avoided, which would lead to the gasification loss of magnesium. By introducing an appropriate amount of inert gas into the furnace before melting the magnesium ingot, the gasification loss of Mg during the smelting process is reduced without breaking the vacuum, thus ensuring the accuracy and stability of the nickel-magnesium master alloy composition.

[0026] 4. This invention uses a vacuum induction melting method to prepare nickel-magnesium master alloys. The equipment is simple and easy to operate, and the configured steam filtration device can effectively remove magnesium vapor from the furnace, ensuring the safety of the production process. Moreover, the production process does not involve polluting gases or other factors, making it more environmentally friendly.

[0027] 5. The method for preparing nickel-magnesium master alloy of the present invention is simple and applicable, and suitable for large-scale industrial production.

[0028] 6. The nickel-magnesium master alloy prepared by this invention has a uniform composition, high cleanliness and no inclusions, and low content of harmful gas elements. When used as a smelting additive for high-temperature alloys, it can be broken into alloy blocks with a size of less than 50mm. It also reduces the burn-off of low-melting-point element magnesium, reduces the introduction of harmful gas elements and inclusions, shortens the alloy melting time, and facilitates the rapid diffusion of alloy elements in the high-temperature alloy melt, resulting in a high-temperature alloy product with more uniform composition and superior performance.

[0029] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the steam filtration system configured in the induction melting furnace of the present invention.

[0031] Figure 2 This is a SEM scan of the nickel-magnesium master alloy prepared in Example 1 of the present invention.

[0032] Figure 3 This is a distribution diagram of Ni element in the nickel-magnesium master alloy prepared in Example 1 of the present invention.

[0033] Figure 4 This is a distribution diagram of Mg element in the nickel-magnesium master alloy prepared in Example 1 of the present invention.

[0034] Explanation of reference numerals in the attached figures

[0035] Detailed Implementation

[0036] like Figure 1 As shown, the steam filtration system configured in the induction melting furnace of the present invention includes a condenser 2 installed at the furnace body 1 interface of the induction melting furnace. The condenser 2 is equipped with a stacked water-cooled baffle 3 inside, and an oil tank filter 4 is installed at the rear end of the condenser 2.

[0037] Example 1

[0038] The high-temperature alloy nickel-magnesium master alloy of this embodiment is composed of the following elements by mass percentage: Mg 15%, with the balance being Ni and unavoidable impurities.

[0039] The preparation method of the high-temperature alloy nickel-magnesium master alloy in this embodiment includes the following steps:

[0040] Step 1: Select electrolytic nickel and magnesium ingots as raw materials. After cutting and grinding the raw materials to remove surface oil and oxide scale, calculate the proportion of nickel-magnesium master alloy for high-temperature alloy of the target product and weigh and package 42kg of plate-shaped electrolytic nickel and 8kg of magnesium ingot pieces.

[0041] The electrolytic nickel conforms to the Ni9999 specification and composition requirements in GB / T 6516-2010 "Electrolytic Nickel", and the magnesium ingot conforms to the Mg9995 composition requirements in GB / T 3499-2003 "Primary Magnesium Ingots". The cut and polished magnesium ingots are small pieces with lengths of 10cm~15cm, widths of 5cm~10cm, and thicknesses of 3cm~5cm. The cut and polished electrolytic nickel are plates with lengths of 3cm~5cm, widths of 3cm~5cm, and thicknesses of 0.5cm~1.5cm.

[0042] Step 2: Place the weighed and packaged plate-shaped electrolytic nickel and magnesium ingot pieces from Step 1 into a molybdenum crucible with a mass purity of 99.95% in the induction melting furnace, with the magnesium ingot pieces at the bottom and the plate-shaped electrolytic nickel on top. Close the furnace lid and evacuate to a vacuum level of 2.3 × 10⁻⁶. -1Pa, then start the heating power supply to heat and melt, using stepped power supply heating, holding at 20kW, 55kW and 85kW for 15min each. When the raw material turns red while the power is maintained at 55kW, argon gas is introduced to -0.045MPa, then the power is increased to 100kW until the raw material is completely melted, then the power is reduced to 80kW and melting is continued for 10min, obtaining the alloy melt in the crucible;

[0043] Step 3: Start the steam filtration system of the induction melting furnace, pour the alloy melt in the crucible from Step 2 into the cast iron ingot mold, and after cooling for 10 hours, open the furnace to take a sample to obtain a nickel-magnesium master alloy ingot. Then, refine, screen, inspect, and package the nickel-magnesium master alloy ingot.

[0044] The composition of the nickel-magnesium master alloy ingot prepared in this embodiment was analyzed, and the results are shown in Table 1 below.

[0045] Table 1. Chemical composition (wt.%) of the nickel-magnesium master alloy ingot prepared in Example 1

[0046]

[0047] As shown in Table 1, the nickel-magnesium master alloy prepared in this embodiment has very low levels of impurity elements, especially oxygen and nitrogen, thus avoiding any impact on the cleanliness of downstream high-temperature alloys.

[0048] Figure 2 This is a SEM scan of the nickel-magnesium master alloy prepared in this embodiment. Figure 3 and Figure 4 The distribution diagrams of Ni and Mg elements in the nickel-magnesium master alloy prepared in this embodiment are shown below, combined with... Figures 2-4 It can be seen that the nickel and magnesium elements are uniformly distributed in the nickel-magnesium master alloy, and no inclusions or segregation were found in the nickel-magnesium master alloy.

[0049] Example 2

[0050] The high-temperature alloy nickel-magnesium master alloy of this embodiment is composed of the following elements by mass percentage: Mg 4%, with the balance being Ni and unavoidable impurities.

[0051] The preparation method of the high-temperature alloy nickel-magnesium master alloy in this embodiment includes the following steps:

[0052] Step 1: Select electrolytic nickel and magnesium ingots as raw materials. After cutting and grinding the raw materials to remove surface oil and oxide scale, calculate the proportion of nickel-magnesium master alloy for high-temperature alloy of the target product and weigh and package 48kg of plate-shaped electrolytic nickel and 2.3kg of magnesium ingot pieces.

[0053] The electrolytic nickel conforms to the Ni9999 specification and composition requirements in GB / T 6516-2010 "Electrolytic Nickel", and the magnesium ingot conforms to the Mg9995 composition requirements in GB / T 3499-2003 "Primary Magnesium Ingots". The cut and polished magnesium ingots are small pieces with lengths of 10cm~15cm, widths of 5cm~10cm, and thicknesses of 3cm~5cm. The cut and polished electrolytic nickel are plates with lengths of 3cm~5cm, widths of 3cm~5cm, and thicknesses of 0.5cm~1.5cm.

[0054] Step 2: Place the weighed and packaged plate-shaped electrolytic nickel and magnesium ingot pieces from Step 1 into a molybdenum crucible with a mass purity of 99.95% in the induction melting furnace, with the magnesium ingot pieces at the bottom and the plate-shaped electrolytic nickel on top. Close the furnace lid and evacuate to a vacuum level of 4.6 × 10⁻⁶. -1 Pa, then start the heating power supply to heat and melt, using stepped power supply heating, holding at 20kW, 55kW and 85kW for 15min each. When the raw material turns red while the power is maintained at 55kW, argon gas is introduced to -0.04MPa, then the power is increased to 100kW until the raw material is completely melted, then the power is reduced to 90kW and melting continues for 5min, obtaining the alloy melt in the crucible;

[0055] Step 3: Start the steam filtration system of the induction melting furnace, pour the alloy melt in the crucible from Step 2 into the cast iron ingot mold, and after cooling for 10 hours, open the furnace to take a sample to obtain a nickel-magnesium master alloy ingot. Then, refine, screen, inspect, and package the nickel-magnesium master alloy ingot.

[0056] The composition of the nickel-magnesium master alloy ingot prepared in this embodiment was analyzed, and the results are shown in Table 2 below.

[0057] Table 2 Chemical composition (wt.%) of the nickel-magnesium master alloy ingot prepared in Example 2

[0058]

[0059] As shown in Table 2, the nickel-magnesium master alloy prepared in this embodiment has very low levels of impurity elements, especially oxygen and nitrogen, thus avoiding any impact on the cleanliness of downstream high-temperature alloys.

[0060] Example 3

[0061] The high-temperature alloy nickel-magnesium master alloy of this embodiment is composed of the following elements by mass percentage: Mg 50%, with the balance being Ni and unavoidable impurities.

[0062] The preparation method of the high-temperature alloy nickel-magnesium master alloy in this embodiment includes the following steps:

[0063] Step 1: Select electrolytic nickel and magnesium ingots as raw materials. After cutting and grinding the raw materials to remove surface oil and oxide scale, calculate the proportion of nickel-magnesium master alloy for high-temperature alloy of the target product and weigh it into 26kg plate-shaped electrolytic nickel and 25kg magnesium ingot pieces.

[0064] The electrolytic nickel conforms to the Ni9999 specification and composition requirements in GB / T 6516-2010 "Electrolytic Nickel", and the magnesium ingot conforms to the Mg9995 composition requirements in GB / T 3499-2003 "Primary Magnesium Ingots". The cut and polished magnesium ingots are small pieces with lengths of 10cm~15cm, widths of 5cm~10cm, and thicknesses of 3cm~5cm. The cut and polished electrolytic nickel are plates with lengths of 3cm~5cm, widths of 3cm~5cm, and thicknesses of 0.5cm~1.5cm.

[0065] Step 2: Place the weighed and packaged plate-shaped electrolytic nickel and magnesium ingot pieces from Step 1 into a molybdenum crucible with a mass purity of 99.95% in the induction melting furnace, with the magnesium ingot pieces at the bottom and the plate-shaped electrolytic nickel on top. Close the furnace lid and evacuate to a vacuum level of 4.6 × 10⁻⁶. -1 Pa, then start the heating power supply to heat and melt, using stepped power supply, maintaining at 20kW, 55kW and 85kW for 15min each. When the raw material turns red while the power is maintained at 55kW, argon gas is introduced to -0.05MPa, then the power is increased to 100kW until the raw material is completely melted, then the power is reduced to 70kW and melting continues for 5min, obtaining the alloy melt in the crucible;

[0066] Step 3: Start the steam filtration system of the induction melting furnace, pour the alloy melt in the crucible from Step 2 into the cast iron ingot mold, and after cooling for 12 hours, open the furnace to take a sample to obtain a nickel-magnesium master alloy ingot. Then, refine, screen, inspect, and package the nickel-magnesium master alloy ingot.

[0067] The composition of the nickel-magnesium master alloy ingot prepared in this embodiment was analyzed, and the results are shown in Table 3 below.

[0068] Table 3 Chemical composition (wt.%) of the nickel-magnesium master alloy ingot prepared in Example 3

[0069]

[0070] As shown in Table 3, the nickel-magnesium master alloy prepared in this embodiment has very low levels of impurity elements, especially oxygen and nitrogen, thus avoiding any impact on the cleanliness of downstream high-temperature alloys.

[0071] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Any simple modifications, alterations, and equivalent changes made to the above embodiments based on the inventive essence shall still fall within the protection scope of the present invention.

Claims

1. A method of producing a nickel-magnesium master alloy for high temperature alloys, the nickel-magnesium master alloy consisting of the following elements in mass percent: Mg 4%~50%, the balance being Ni and unavoidable impurities, characterized in that the method comprises the following steps: Step one, select electrolytic nickel and magnesium ingot as raw material, after cutting and polishing, according to the purpose product high temperature alloy with nickel magnesium intermediate alloy ratio calculation and weighing subpackaging; Step two, the raw material weighed and subpackaged in step one is loaded into the crucible of the induction melting furnace, vacuum and power heating melting, after the raw material is red, fill in argon, after the raw material is completely melted, reduce the power by 10kW~30kW continue to melt 5min~10min, obtain alloy melt in the crucible; the crucible is molybdenum crucible with mass purity of 99.95%; Step three, start the vapor filtration system of the induction melting furnace, pour the alloy melt in the crucible in step two into the cast iron ingot mold, cool for 10h~12h, then open the furnace and take sample to obtain nickel magnesium intermediate alloy ingot, and then finish, screen, test and package the nickel magnesium intermediate alloy ingot.

2. The method of claim 1, wherein the nickel-magnesium master alloy for high-temperature alloys is prepared by the steps of: preparing a mixture of nickel and magnesium; and melting the mixture to prepare the nickel-magnesium master alloy for high-temperature alloys. The unavoidable impurities include the following elements with mass percentage: Ag≤0.001%, Co≤0.01%, Fe≤0.1%, Mn≤0.05%, Cu≤0.003%, As≤0.002%, Sn≤0.001%, Zn≤0.002%, Si≤0.02%, P≤0.01%, C≤0.05%, S≤0.005%, O≤0.005%, N≤0.007%.

3. The method of claim 1, wherein the nickel-magnesium master alloy for high-temperature alloys is prepared by the steps of: preparing a mixture of nickel and magnesium; and melting the mixture to prepare the nickel-magnesium master alloy for high-temperature alloys. The electrolytic nickel in step one meets the requirements of Ni9999 specification and composition in GB / T 6516-2010 "Electrolytic nickel", and the magnesium ingot meets the composition requirements of Mg9995 in GB / T 3499-2003 "Primary magnesium ingot".

4. The method of claim 1, wherein the nickel-magnesium master alloy for high-temperature alloys is prepared by the steps of: preparing a mixture of nickel and magnesium; and melting the mixture to prepare the nickel-magnesium master alloy for high-temperature alloys. The length, width and thickness of the magnesium ingot after cutting and polishing in step one are 10cm~15cm, 5cm~10cm and 3cm~5cm respectively, and the length, width and thickness of the electrolytic nickel after cutting and polishing are 3cm~5cm, 3cm~5cm and 0.5cm~1.5cm respectively.

5. The method of claim 1, wherein the nickel-magnesium master alloy for high-temperature alloys is prepared by the steps of: preparing a mixture of nickel and magnesium; and melting the mixture to prepare the nickel-magnesium master alloy for high-temperature alloys. The vacuuming in step two is to a vacuum of no more than 5 x 10 -1 Pa.

6. The method of claim 1, wherein the nickel-magnesium master alloy for high-temperature alloys is prepared by the steps of: preparing a mixture of nickel and magnesium; and melting the mixture to prepare the nickel-magnesium master alloy for high-temperature alloys. The mode of power heating melting in step two is stepwise power heating, gradually adjusting the melting power, and keeping at each power for 10min~15min.

7. The method of claim 1, wherein the nickel-magnesium master alloy for high-temperature alloys is prepared by the steps of: preparing a mixture of nickel and magnesium; and melting the mixture to prepare the nickel-magnesium master alloy for high-temperature alloys. In step two, after the raw material is red, the argon is filled to-0.045MPa±0.005MPa.

8. The method of claim 1, wherein the nickel-magnesium master alloy for high-temperature alloys is prepared by the steps of: preparing a mixture of nickel and magnesium; and melting the mixture to prepare the nickel-magnesium master alloy for high-temperature alloys. In step three, the vapor filtration system includes a condenser (2) arranged at the interface of the furnace body (1) of the induction melting furnace, the inside of the condenser (2) is provided with a stacked water-cooled baffle (3), and the rear end of the condenser (2) is provided with an oil pool filter (4).

9. A nickel magnesium intermediate alloy for high temperature alloy, characterized in that it is prepared by the method of any one of claims 1~8.

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