A low-rare earth dross content nickel-based superalloy and a method of making the same

Abstract

The application provides a nickel-based high-temperature alloy with low rare earth dross content and a preparation method thereof, wherein the preparation method comprises the following steps: 1) preparing raw materials according to the chemical composition requirements of the nickel-based high-temperature alloy; the raw materials comprise first raw materials and second raw materials; the second raw materials are used for providing rare earth elements; and the first raw materials are used for providing other elements except the rare earth elements; 2) performing smelting and high-temperature refining on the first raw materials; when low-temperature refining is performed, the second raw materials are added into the melt, the adsorption impurity-removing structure is immersed into the melt after alloying, and at least one compound treatment is performed, so that the adsorption impurity-removing structure adsorbs rare earth oxides and rare earth sulfides in the melt, thereby reducing the content of rare earth dross in the melt; each compound treatment comprises low-temperature refining, power-off and stirring treatment; and 3) performing pouring treatment on the melt to obtain the nickel-based high-temperature alloy with low rare earth dross content. The application is mainly used for reducing the content of rare earth dross in the nickel-based high-temperature alloy.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high-temperature alloy smelting, in particular to a nickel-based high-temperature alloy with low rare earth dross content and a preparation method thereof. BACKGROUND

[0002] Cast nickel-based high-temperature alloys have excellent high-temperature strength, creep resistance, and thermal corrosion and oxidation resistance, and are widely used to prepare advanced turbine blades, guide vanes and other high-temperature structural components. Among them, the creep resistance, fatigue resistance and fatigue-creep interaction resistance of the alloy at high temperature are one of the important indicators for evaluating the alloy. For some complex-shaped static parts that serve at high temperatures, the alloy used to manufacture them not only has good casting performance, but also has excellent oxidation and thermal corrosion resistance. And with the increasing demand for engine thrust-to-weight ratio and the increasing scarcity of international high-temperature alloy raw materials, low density and low cost are also another major trend of high-temperature alloy development.

[0003] Among them, the alloy with less noble metal element content, good long-term aging organizational stability and excellent casting performance is usually suitable for manufacturing some hot end complex thin-walled components, and can also be used to manufacture more complex new type high-efficiency cooling vanes and complex guide vanes in the engine with a thrust-to-weight ratio of 12-15. And because thin-walled parts are usually formed by equiaxed crystal casting process, which is significantly superior to directional solidification casting process in terms of manufacturing cost control and production efficiency, it has great significance for improving the thrust-to-weight ratio of the aero-engine, so it has become one of the preferred conditions for the material of the complex thin-walled structural parts of the current aero-engine.

[0004] The composition characteristics of the alloy of the present application are that a large amount of Nb element is added, and 0.015-0.050% of rare earth element Y is added. Among them, Nb can replace the lattice position of Al atoms in γ'-Ni3Al, play a role of solid solution strengthening γ' phase, and can significantly improve the flow stress of γ' phase, thereby improving the mechanical properties of the alloy; and the rare earth element Y mainly forms a dross of rare earth oxide and sulfide during smelting, and a small amount of Y element solid-solved in the grain boundary can improve the purity of the grain boundary, thereby improving the high-temperature oxidation and hot corrosion resistance of the alloy.

[0005] However, with the increase of the content of rare earth elements in the alloy, due to its high activity, small amount of O and S elements in the melt can form small rare earth oxide and sulfide inclusions during smelting, and it is not easy to be filtered as slag during pouring, resulting in a large amount of small inclusions in the alloy, which can easily form a high dross content during remelting and pouring. If it cannot be completely filtered, it can cause the inclusions of the castings to be scrapped, affecting the qualified rate of the castings.

[0006] Therefore, it is urgent to develop a master alloy preparation process for reducing the content of rare earth float slag in alloy, so as to improve the purity of the rare earth element-containing nickel-based superalloy, and then improve the qualified rate of the alloy castings, which has very important scientific significance and social significance. SUMMARY

[0007] Therefore, the present application provides a nickel-based superalloy with low rare earth float slag content and a preparation method thereof, which mainly aims to reduce the content of rare earth float slag in the nickel-based superalloy.

[0008] To achieve the above-mentioned purpose, the present application mainly provides the following technical solutions:

[0009] On the one hand, the present application provides a preparation method of a nickel-based superalloy with low rare earth float slag content, which comprises the following steps:

[0010] 1) Preparing raw materials according to the chemical composition requirements of the nickel-based superalloy; wherein the raw materials include first raw materials and second raw materials; wherein the second raw materials are used to provide rare earth elements; and the first raw materials are used to provide other elements except rare earth elements;

[0011] 2) First, the first raw materials are subjected to smelting and high-temperature refining; then, when the low-temperature refining is performed, the second raw materials are added to the melt, and after alloying, the adsorption and impurity removal structure is immersed in the melt, and at least one compound treatment is performed, so that the adsorption and impurity removal structure adsorbs the rare earth oxides and rare earth sulfides in the melt, purifies the melt, and reduces the content of rare earth float slag in the melt; wherein each time the compound treatment comprises sequentially performing low-temperature refining, power-off, and stirring treatment;

[0012] 3) The adsorption and impurity removal structure is taken out from the melt, and the melt is subjected to pouring treatment to obtain a nickel-based superalloy with low rare earth float slag content.

[0013] Preferably, the material of the adsorption and impurity removal structure is any one of magnesium oxide ceramic material, aluminum oxide ceramic material, and composite ceramic material of magnesium oxide and aluminum oxide; wherein the mass fraction of magnesium oxide in the magnesium oxide ceramic material is ≥80wt%; and the mass fraction of aluminum oxide in the aluminum oxide ceramic material is ≥80wt%. Preferably, the composite ceramic material of magnesium oxide and aluminum oxide comprises magnesium oxide, aluminum oxide, and silicon dioxide; further preferably, the mass fraction of magnesium oxide is ≥80wt%, the mass fraction of aluminum oxide is 10-15wt%, and the mass fraction of silicon dioxide is 1-5wt%.

[0014] Preferably, the surface of the adsorption impurity-removing structure is of a microporous structure. Preferably, the pore size of the microporous structure is 10-100 microns, so that the adsorption impurity-removing structure has a relatively narrow pore size distribution range and a relatively high porosity. The microporous surface of this porous type has a large internal surface, i.e. a large surface energy, so that the adsorbate and the ceramic material are in sufficient contact, thereby having a strong adsorption capacity and being able to adsorb and filter a large amount of fine suspended particulate matter and inclusions.

[0015] Preferably, the method for preparing the adsorption impurity-removing structure comprises the following steps: placing ceramic powder into a mold and performing isostatic pressing forming treatment to obtain a blank; and performing sintering treatment on the blank to obtain the adsorption impurity-removing structure. Preferably, the particle size of the ceramic powder is ≤400 mesh (here, the inventor of the present application has found that it is relatively difficult to sinter and form if ceramic powder with a particle size of more than 400 mesh is used); preferably, the ceramic powder is selected from one or both of magnesium oxide ceramic powder and aluminum oxide ceramic powder; further preferably, the mass fraction of magnesium oxide in the magnesium oxide ceramic powder is ≥80wt% (i.e. the main component is magnesium oxide, and there is a small amount of aluminum oxide and silicon dioxide); the mass fraction of aluminum oxide in the aluminum oxide ceramic powder is ≥80wt% (i.e. the main component is aluminum oxide, and there can be a small amount of talc); preferably, the pressure of the isostatic pressing forming treatment is 200-600 MPa; the time of the isostatic pressing forming treatment is 2-10 min; preferably, in the step of the sintering treatment: first heat the blank to a temperature of 800±100℃ to perform low-temperature sintering treatment for 3.5-4.5 h, and then heat to 1500±100℃ to perform high-temperature sintering for 2-2.5 h; after cooling, the adsorption impurity-removing structure with a physical adsorption dross effect is obtained.

[0016] Preferably, the adsorption impurity-removing structure is of a rod-like structure.

[0017] Preferably, a fixing groove is arranged on the adsorption impurity-removing structure; wherein the fixing groove is used for fixing a top charging rod or a temperature measuring rod.

[0018] Preferably, if under electromagnetic induction, the flow mode of the melt at the center of the crucible is from top to bottom, then the longitudinal section of the adsorption impurity-removing structure is designed as a normal trapezoid; if under electromagnetic induction, the flow mode of the melt at the center of the crucible is from bottom to top, then the longitudinal section of the adsorption impurity-removing structure is designed as an inverted trapezoid.

[0019] Preferably, the chemical composition of the nickel-based superalloy is as follows in terms of weight percentage: carbon: 0.03-0.15wt%, chromium: 8.00-10.00wt%, cobalt: 4.00-6.00wt%, tungsten: 2.00-5.00wt%, molybdenum: 2.50-3.50wt%, aluminum: 5.50-6.00wt%, niobium: 1.85-2.30wt%, yttrium: 0.005-0.050wt%, boron: 0.001-0.035wt%, zirconium: 0.001-0.007wt%, rhenium: 0-0.2wt%, oxygen: 0-0.002wt%, nitrogen 0-0.002wt%, sulfur 0-0.002wt%, and the balance being nickel.

[0020] Preferably, the content of oxygen, nitrogen and sulfur in the nickel-based superalloy is ≤20ppm.

[0021] Preferably, the nickel-based superalloy is an equiaxed nickel-based superalloy.

[0022] Preferably, in the step 1), the second raw material comprises Al-Y intermediate alloy.

[0023] Preferably, in the step 1), the first raw material comprises carbon, chromium, cobalt, tungsten, molybdenum, aluminum, niobium, boron, zirconium, nickel, and preferably further comprises rhenium.

[0024] Preferably, in the step 2), before vacuum induction melting of the first raw material, cobalt, carbon, tungsten, molybdenum, niobium, chromium and nickel are sequentially arranged in the crucible, and then melting and high-temperature refining are performed; wherein, after the high-temperature refining is completed, aluminum, boron and zirconium are added to the melt, and then low-temperature refining is performed; preferably, when the first raw material further comprises rhenium, the rhenium is added to the melt after the cobalt, carbon, tungsten, molybdenum, niobium, chromium and nickel are completely melted and before the high-temperature refining; preferably, the temperature of the high-temperature refining is 1480-1550℃.

[0025] Preferably, in the step 2), the temperature of the low-temperature refining is 1380-1420℃; and / or in each complex treatment including low-temperature refining, power-off and stirring treatment, the time of the low-temperature refining is 5-30min (stirring immediately after power-off); and / or the adsorption impurity removal structure is first baked on the surface of the melt for at least 1min, and then slowly immersed in the melt; and / or the depth of the adsorption impurity removal structure immersed in the melt is 1 / 2-2 / 3 of the depth of the melt; and / or the volume of the adsorption impurity removal structure immersed in the melt is about 1 / 5-1 / 4 of the volume of the melt; and / or the adsorption impurity removal structure is immersed in the melt from the center position of the liquid surface.

[0026] Preferably, in the step 2), if the weight of the raw material is ≤10 Kg, the number of times of the composite treatment is 1-2, and the time of each stirring treatment is 0.5-2 min; if the weight of the raw material is greater than 10 Kg and ≤50 Kg, the number of times of the composite treatment is 1-3, and the time of each stirring treatment is 1-3 min; if the weight of the raw material is greater than 50 Kg and ≤200 Kg, the number of times of the composite treatment is 3-5, and the time of each stirring treatment is 2-4 min; if the weight of the raw material is greater than 200 Kg and ≤500 Kg, the number of times of the composite treatment is 4-7, and the time of each stirring treatment is 3-6 min; if the weight of the raw material is greater than 500 Kg, the time of each stirring treatment is ≥5 min.

[0027] In another aspect, the embodiment of the present application provides a low rare earth dross content nickel-based superalloy, characterized in that the chemical composition of the nickel-based superalloy in percentage by weight is as follows: carbon: 0.03-0.15 wt%, chromium: 8.00-10.00 wt%, cobalt: 4.00-6.00 wt%, tungsten: 2.00-5.00 wt%, molybdenum: 2.50-3.50 wt%, aluminum: 5.50-6.00 wt%, niobium: 1.85-2.30 wt%, yttrium: 0.005-0.050 wt%, boron: 0.001-0.035 wt%, zirconium: 0.001-0.007 wt%, rhenium: 0-0.2 wt%, oxygen: 0-0.002 wt%, nitrogen 0-0.002 wt%, sulfur 0-0.002 wt%, and the balance being nickel; wherein the dross content in the nickel-based superalloy is ≤3 wt%; preferably, the low rare earth dross content nickel-based superalloy is prepared by the preparation method of the low rare earth dross content nickel-based superalloy according to any one of the preceding items; preferably, the sum of the contents of oxygen, nitrogen and sulfur in the nickel-based superalloy is ≤20 ppm.

[0028] Compared with the prior art, the low rare earth dross content nickel-based superalloy and the preparation method thereof have at least the following beneficial effects:

[0029] Since the size of rare earth inclusions formed during alloy smelting is usually less than 1mm, and in a suspended state in the melt, it is not only difficult to grow, float to form macroscopic dross, but also difficult to remove by filter screen, and after pouring into the top die, it usually exists in the form of carbide core or grain boundary inclusion. However, when secondary remelting is carried out, part of the fine inclusions in the alloy ingot will float as dross, and the other part will continue to suspend in the melt, and continue to act as carbide core or grain boundary inclusion after pouring into the casting. In view of the above technical problems existing in the prior art, the embodiment of the present application proposes a preparation method of a low-rare earth dross content nickel-based high-temperature alloy, which comprises the following steps: adding rare earth to the melt during low-temperature refining, after alloying, immersing the adsorption and impurity removal structure into the melt, and cooperating with at least one composite treatment (each composite treatment comprises: sequentially performing low-temperature refining, power-off and stirring treatment), so that the adsorption and impurity removal structure adsorbs rare earth oxides and rare earth sulfides in the melt, and the melt is purified, thereby reducing the rare earth dross content in the melt. It should be noted that the composite treatment and the adsorption and impurity removal structure have a synergistic impurity removal effect: the repeated composite treatment makes the melt fully alloyed and has a certain flowability in the crucible, so that the melt can fully contact the surface of the ceramic rod during stirring, and the inclusions in the melt are adsorbed out with the melt flow process through the adsorption effect of the surface of the microporous ceramic material.

[0030] Further, the embodiment of the present application provides a preparation method of a low-rare earth dross content nickel-based high-temperature alloy, which comprises the following steps: using an adsorption and impurity removal structure made of high-alumina, high-magnesia or alumina-magnesia ceramic material, and the adsorption and impurity removal structure has a microporous surface structure, so that the adsorption and impurity removal structure has high thermal stability, and can avoid reaction with the melt and avoid the formation of new inclusions, and also makes the adsorption and impurity removal structure have a structure similar to the crucible (increasing the effective contact area of the melt with the crucible material), thereby promoting the deoxidation and denitrification reactions during alloy smelting, and having a positive effect on improving the purity of the high-temperature alloy ingot.

[0031] In addition, the present application is suitable for the purification preparation of most high-temperature alloy ingots containing rare earth elements, and the size and shape of the impurity removal and adsorption device can be freely designed according to the weight of the alloy or the different flow field conditions of the melt under electromagnetic induction, which is flexible, variable and practical.

[0032] Furthermore, the adsorption and impurity removal structure of this invention differs from existing foam ceramic filters in that: the overall structure is rod-shaped, and the surface has a microporous structure; the preparation process of the adsorption and impurity removal structure in this application utilizes isostatic pressing technology in the early stages, and the size and shape of the adsorption and impurity removal structure can be freely designed according to the weight of the smelting alloy or the different flow field conditions of the melt under electromagnetic induction, making it flexible, versatile, and highly practical. For example, if the melt flows from top to bottom in the center of the crucible under electromagnetic induction (the melt flow direction is controlled by the induction furnace; if an electromagnetic stirring function is included, the stirring direction can be freely selected), it can be designed as a positive trapezoid; if the melt flows from bottom to top in the center of the crucible under electromagnetic induction, it can be designed as an inverted trapezoid. This design increases the contact area between the flowing melt and the surface of the adsorption and impurity removal structure, improving the impurity removal effect.

[0033] It should also be noted that existing foam-like ceramic filters are made by first preparing ceramic powder into a liquid slurry, then immersing a special polyurethane foam into the slurry. After the foam vaporizes, a blank is obtained, which is then dried and sintered. The filter's pore structure is similar to that of the foam. In contrast, the adsorption and impurity removal structure of this invention is formed by isostatically pressing ceramic powder with a particle size less than 400 mesh into a mold to obtain a blank with a pore size of 10-100 μm, which is then sintered to obtain the adsorption and impurity removal structure. Therefore, the surface microporous structure of the adsorption and impurity removal structure of this application is significantly different from the pore structure of existing filters, resulting in different adsorption effects and adsorption principles.

[0034] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0035] Figure 1 The slag condition of alloys prepared by Example 1 of the present invention and conventional processes during remelting and use is shown; wherein, Figure 1 Figure (a) shows the slag condition of the alloy prepared in Example 1 during remelting; Figure 1 Figure (b) shows the slag situation when the alloy prepared by conventional process is remelted and used.

[0036] Figure 2 This describes the slag condition of alloys prepared by Example 2 of the present invention and conventional processes during remelting and use; wherein, Figure 2 Figure (a) shows the slag condition of the alloy prepared in Example 1 during remelting; Figure 2 Figure (b) shows the slag situation when the alloy prepared by conventional process is remelted and used.

[0037] Figure 3is a structural diagram of the adsorption impurity removal structure.

[0038] Figure 4 is another structural diagram of the adsorption impurity removal structure. DETAILED DESCRIPTION

[0039] In order to further clarify the technical means and effects adopted by the present application to achieve the predetermined inventive objectives, the following describes the specific embodiments, structures, features and effects according to the present application in detail with reference to the accompanying drawings and preferred embodiments. In the following description, different "an embodiment" or "embodiments" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0040] Since the size of the rare earth inclusions formed during alloy smelting is usually less than 1 mm and in a suspended state in the melt, it is not only difficult to grow, float and form macroscopic dross, but also difficult to remove by filter screen (because the density of the inclusions is much greater than that of the gas, the size of the rare earth inclusions formed during smelting is very small, usually less than 1 mm, plus the flow of the metal liquid, so the inclusions are much more difficult to remove than the gas bubbles, and the mesh size of the filter screen is larger than the size of the inclusions). After pouring into the top mold, it usually exists in the form of carbide core or grain boundary inclusion. However, when secondary remelting is performed, part of the fine inclusions in the alloy ingot will float as dross, and the other part will continue to suspend in the melt and enter the casting with pouring, continuing to act as carbide core or grain boundary inclusion. Therefore, reducing the content of rare earth dross in the master alloy is of great significance to improve the purity of high-temperature alloy castings.

[0041] The concept of the present application is as follows: the present application prepares a high-purity alloy melt first, and then adds rare earth elements at low temperature (to ensure the yield of rare earth elements). The melt is kept at a temperature of about 1380-1420℃ on the surface, and low-temperature refining is performed. During this process, the adsorption impurity removal structure (for example, high-alumina or high-magnesia ceramic rod) is inserted into the smelting melt as a device for physically adsorbing dross. The melt is fully alloyed and has a certain flowability in the crucible through the composite treatment of repeated composite treatment of keeping at 1380-1420℃, power failure, stirring, and reheating to the power failure temperature…… The fine rare earth oxides and sulfides in the melt are adsorbed on the surface of the adsorption impurity removal structure during the flow of the melt through the surface adsorption of the ceramic material. Before pouring, the adsorption impurity removal structure is removed through the upper charging / temperature measuring rod, thereby achieving the effect of reducing the content of inclusions in the melt. The specific scheme of the present application is as follows:

[0042] The present application provides a preparation method of a nickel-based high-temperature alloy with low rare earth dross content, which comprises the following steps:

[0043] 1) preparing raw materials according to the chemical composition requirements of the nickel-based superalloy; wherein, the raw materials include first raw materials and second raw materials; wherein, the second raw materials are used to provide rare earth elements; and the first raw materials are used to provide other elements except the rare earth elements.

[0044] In this step, the chemical composition of the nickel-based superalloy is as follows: carbon: 0.03-0.15wt%, chromium: 8.00-10.00wt%, cobalt: 4.00-6.00wt%, tungsten: 2.00-5.00wt%, molybdenum: 2.50-3.50wt%, aluminum: 5.50-6.00wt%, niobium: 1.85-2.30wt%, yttrium: 0.005-0.050wt%, boron: 0.001-0.035wt%, zirconium: 0.001-0.007wt%, rhenium: 0-0.2wt%, oxygen: 0-0.002wt%, nitrogen 0-0.002wt%, sulfur 0-0.002wt%, and the balance is nickel.

[0045] Here, it needs to be explained about the above-mentioned alloy that: the above-mentioned alloy contains a large amount of rare earth elements, and the adsorption and impurity removal structure mentioned in the present application can solve the problem that the large amount of rare earth oxides in such rare earth-containing alloy can easily lead to a high content of dross during subsequent use.

[0046] Among them, the high-temperature alloy is an equiaxed crystal nickel-based superalloy. It should be noted that equiaxed crystals usually have a short pouring time, and if the dross is poured onto the shell and floats up for a short time, it is easy to form inclusions in the casting. For single crystals and columnar crystals, the directional solidification time is longer, and the dross has sufficient time to float up.

[0047] To ensure low dross content, it is required that [O]+[N]+[S]≤20ppm.

[0048] Preferably, the first raw materials include: cobalt, carbon, tungsten, molybdenum, niobium, chromium, nickel, aluminum, boron, zirconium; and preferably also include rhenium.

[0049] Preferably, the second raw materials include Al-Y.

[0050] 2) First, the first raw materials are melted and high-temperature refined; then, when the low-temperature refining is performed, the second raw materials are added to the melt, the adsorption and impurity removal structure is immersed in the melt after alloying, and at least one compound treatment is performed to make the adsorption and impurity removal structure adsorb the rare earth oxides and rare earth sulfides in the melt, purify the melt, and reduce the content of rare earth dross in the melt; wherein each compound treatment includes low-temperature refining, power-off, and stirring treatment.

[0051] The order of adding raw materials is cobalt, carbon, tungsten, molybdenum, niobium, chromium, nickel, rhenium, aluminum, boron, zirconium, and yttrium.

[0052] In order to ensure that the melt is rapidly formed in the crucible during the cleaning stage, and to avoid oxidation of the raw materials and the formation of high-melting-point compounds, cobalt, carbon, tungsten, molybdenum, niobium, chromium and nickel can be used as the distribution sequence when the cold crucible is loaded. In order to ensure the yield of rare and precious metals such as rhenium, aluminum, boron, zirconium, yttrium, trace elements and rare earth elements, rhenium can be added after cobalt, carbon, tungsten, molybdenum, niobium, chromium and nickel are completely cleaned; aluminum, boron, titanium and zirconium can be added after high-temperature refining (the surface temperature of the melt is about 1480-1550°C) is completed; yttrium can be added when entering the low-temperature refining stage (the surface temperature of the melt is about 1380-1420°C). Among them, yttrium is added in the form of a second raw material (such as Al-Y intermediate alloy).

[0053] In addition, the size of the ceramic rod should be designed to meet the requirements that the immersion depth of the melt is about 1 / 2-2 / 3 of the melt depth, and the immersion volume of the melt is about 1 / 5-1 / 4 of the melt volume. Due to the flow direction of the melt under electromagnetic heating and stirring is usually from the center to the periphery or from the periphery to the center, the ceramic rod can be immersed in the melt from the center of the liquid surface, thereby ensuring that the melt can fully contact the surface of the ceramic rod during stirring.

[0054] 3) The adsorption and impurity removal structure is taken out from the melt, and the melt is poured to obtain a nickel-based high-temperature alloy with low rare earth dross content.

[0055] In this step, after the smelting process is completed, the adsorption and impurity removal structure is taken out, and the alloy liquid is poured into an ingot mold. After solidification, an alloy ingot is formed, and a nickel-based high-temperature alloy with low rare earth dross content is obtained.

[0056] Preferably, the preparation method of the adsorbing and impurity removing structure of the present application is as follows: ceramic powder with particle size of 400 mesh or less is selected as raw material, wherein the ceramic powder is one or both of magnesium oxide ceramic powder and aluminum oxide ceramic powder; the mass fraction of magnesium oxide in the magnesium oxide ceramic powder is ≥80wt%; and the mass fraction of aluminum oxide in the aluminum oxide ceramic powder is ≥80wt%. For the convenience of molding, the ceramic powder is put into a mold with length, width and height of about (20±10)mm×(20±10)mm×(100-300)mm or similar proportion and volume, and the process of isostatic pressing at a pressure of 200-600MPa for about 2-10min is adopted according to the actual situation to ensure the shaping according to the size and shape. Then, the ceramic powder is put into a sintering furnace for sintering, and the sintering process is as follows: (800±100)℃×4h+(1500±100)℃×2h, and after the end, the sintering furnace is cooled to below 400℃ and then the sintering furnace is taken out, so that the adsorbing and impurity removing structure with the physical adsorption of dross effect is obtained. Here, the adsorbing and impurity removing structure with high aluminum, high magnesium or aluminum-magnesium ceramic material is adopted, and the adsorbing and impurity removing structure has a microporous surface structure, so that the thermal stability of the adsorbing and impurity removing structure is high, and the adsorbing and impurity removing structure can avoid reaction with the melt and avoid the formation of new inclusions. The pore size of the microporous structure of the adsorbing and impurity removing structure is 10-100μm, so that the adsorbing and impurity removing structure has a relatively narrow pore size distribution range and a relatively high porosity. The porous micro-surface characteristics make the adsorbing and impurity removing structure have a large internal surface, i.e. a large surface energy, so that the adsorbed substances can fully contact with the ceramic material, thereby having a strong adsorption capacity and being able to adsorb and filter a large amount of small suspended particulate matters and inclusions. Here, the prior art mainly uses a filter screen to filter impurities, but the size of rare earth dross is small and difficult to remove by the filter screen. In addition, the prior art is also beneficial to the ceramic ball impurity removal, but the ceramic ball is not easy to add, and is easy to adhere to the crucible in continuous production.

[0057] The present application is suitable for the purification preparation of most high-temperature alloy ingots containing rare earth elements, and the size and shape of the adsorbing and impurity removing structure can be freely designed according to the weight of the alloy or the different flow field conditions of the melt under electromagnetic induction, which is flexible, variable and practical. For example, if the flow mode of the melt at the center of the crucible under electromagnetic induction is from top to bottom (the melt flow direction is controlled by the induction furnace, and if the electromagnetic stirring function is attached, the stirring direction can be freely selected), the cross section of the adsorbing and impurity removing structure is designed as a right trapezoid (see Figure 4 ), and preferably the whole adsorbing and impurity removing structure is rod-shaped. In this way, the contact area between the flowing melt and the surface of the adsorbing and impurity removing structure is increased, and the impurity removal effect is improved. If the flow mode of the melt at the center of the crucible under electromagnetic induction is from bottom to top, the cross section of the adsorbing and impurity removing structure is designed as an inverted trapezoid (see Figure 3 ), and in this way, the contact area between the flowing melt and the surface of the adsorbing and impurity removing structure is increased, and the impurity removal effect is improved. For example, Figure 3 and Figure 4As shown, the size of the adsorption and impurity removal structure 1 can be freely designed according to the structure of the smelting furnace. The fixing groove 2 on the adsorption and impurity removal structure 1 is used to fix the design device to the rear temperature measuring rod of the top charging rod through a nickel wire, so as to facilitate operation.

[0058] It should be further explained that under electromagnetic induction, if the flow mode of the melt at the center of the crucible is from bottom to top, the cross section of the adsorption and impurity removal structure is designed as an inverted trapezoid. In this way, during the upward flow of the melt, as the side wall surface of the adsorption structure gradually increases, the contact area between the flowing melt and the surface of the adsorption and impurity removal structure also gradually increases. Through the adsorption effect of the surface of the micropores of the ceramic material, the inclusions in the melt are adsorbed out during the flow of the melt, thereby further improving the impurity removal effect. Similarly, if the flow mode of the melt at the center of the crucible is from top to bottom, the cross section of the adsorption and impurity removal structure is designed as a trapezoid, which can further improve the impurity removal effect.

[0059] According to the above scheme, the present application provides a preparation method of a nickel-based high-temperature alloy with low rare earth dross content, and the specific implementation steps are as follows:

[0060] (1) According to the composition and size of the crucible, ceramic powder (high alumina, high magnesium or aluminum-magnesium powder) is prepared, and the adsorption and impurity removal structure with the required size and shape is prepared by hot isostatic pressing, and then is placed into a ceramic sintering furnace for sintering according to the corresponding process of the ceramic type.

[0061] (2) The rare earth raw material is weighed according to the composition requirement and the burning loss, and is tightly wrapped with a nickel foil.

[0062] (3) The vacuum induction melting is carried out according to the purification smelting process. When the low-temperature refining stage is reached, the rare earth element is added to the alloy melt, and after sufficient alloying, the adsorption and impurity removal structure is fixed on the top charging rod or the temperature measuring rod. After baking on the surface of the melt for more than 1 min, it is slowly immersed into the melt to prevent the ceramic from being broken due to thermal expansion.

[0063] (4) The alloying and impurity removal process is carried out according to the weight of the smelted alloy. The parameters of the alloying process are consistent with those of the low-temperature refining. The stirring power during the impurity removal period is about the high-temperature refining power. For different charging weights, the relationship between the stirring frequency and time is shown in Table 1.

[0064] Table 1 shows the relationship between the stirring frequency and time and the charging weight.

[0065] Charge weight Number of stirrings Single stirring time, min ≤ 10 kg 1 1 ≤ 50 kg 2 2 ≤ 200 kg 5 3 ≤ 500 kg 6 5 > 500 kg ≥7 ≥5

[0066] (5) After the last stirring is completed, the adsorption and impurity removal structure is taken out, and the temperature of the melt is increased to the pouring temperature required by the process, and the alloy ingot is poured to obtain the nickel-based high-temperature alloy with low rare earth dross content.

[0067] The application will be further explained below by means of specific embodiments.

[0068] Embodiment 1

[0069] In this embodiment, a nickel-based superalloy with low rare earth dross content is prepared. Specifically, a 500 kg vacuum induction furnace is used to prepare a master alloy ingot, and the feeding amount is 450 kg. The main steps are as follows:

[0070] 1) A high-alumina ceramic rod is prepared as an adsorption and impurity removal structure by isostatic pressing + sintering process, with a size of about φ200*500mm. 3 And a groove with a depth of about 20mm is polished at a distance of about 50mm from the upper end (fixing groove) to fix it at the temperature measuring rod.

[0071] In this embodiment, the specific raw materials of the adsorption and impurity removal structure in this step are as follows: the ceramic powder is high-alumina ceramic, the mass fraction of alumina in the ceramic powder is ≥80wt%, and the particle size is ≤400 mesh. The specific preparation steps are as follows: the ceramic powder is placed in a mold, and a 300MPa pressure isostatic pressing process is used for about 6min to ensure shaping. Then it is put into a sintering furnace for sintering, and the sintering process is: 800℃*4h+1500℃*2h, after the end, it is taken out after the furnace is cooled to below 400℃, and the adsorption and impurity removal structure with a porous microstructure on the surface is obtained; wherein the pore size of the porous microstructure is 10-100μm. The adsorption and impurity removal structure is a rod structure. A fixing groove is provided on the adsorption and impurity removal structure; wherein the fixing groove is used to fix the temperature measuring rod. The longitudinal section of the adsorption and impurity removal structure is designed as a right trapezoid.

[0072] 2) Al-Y is used as the main raw material for adding rare earth, and the batching point is Y: 0.05wt%, and the nickel foil is wrapped after weighing.

[0073] 3) The raw materials are matched according to Table 2.

[0074] Table 2 Chemical composition matching of the alloy prepared in this embodiment, wt%

[0075] C Cr Co W Mo Al Nb Y B Zr Ni 0.10 9.50 5.00 3.50 3.00 6.00 2.00 0.05 0.02 0.005 Bal.

[0076] Specifically, first, cobalt, carbon, tungsten, molybdenum, niobium, chromium, and nickel are sequentially matched in the crucible, and then vacuum induction melting is carried out. After the alloy is liquefied and clear, high-temperature refining (1480-1550℃) is carried out. After the high-temperature refining is completed, aluminum, boron, and zirconium are added to the melt. Then, the low-temperature refining stage (the surface temperature of the melt is about 1380-1420℃) is entered, the second raw material Al-Y is added to the melt, and 5min electromagnetic stirring (alloying) is carried out to ensure uniformity of the composition.

[0077] 4) Fix the adsorbing impurity structure on the temperature measuring rod with iron wire, and close the top charging turret, and vacuumize to below 10 Pa.

[0078] Open the top charging plug valve, close the vacuum pump unit, and fill argon until the vacuum gauge shows about 0.06 MPa, then extend the adsorbing impurity structure into the furnace body until it just contacts the liquid surface, hover for about 3 min, and then slowly immerse into the melt until the exposed part is about 1 / 3 of the total length of the ceramic rod, and the immersion process lasts about 4 min.

[0079] 5) At the holding temperature of 1380-1420℃, sequentially perform low-temperature refining (5 min), power-off, stirring (5 min), and re-heating to the holding temperature before power-off, and so on for a total of 6 times, so that the melt is fully alloyed and has certain fluidity in the crucible. If solidification of the alloy liquid surface occurs during the process, the heating power can be increased to melt the surface solidified alloy.

[0080] In addition, under electromagnetic induction, the flow mode of the melt in the center of the crucible is from top to bottom.

[0081] 6) After the last stirring is completed, slowly take out the ceramic rod, and the taking-out time is about 5 min. This process should avoid too fast taking-out speed to cause thermal cracking of the ceramic rod and falling into the alloy liquid.

[0082] 7) After the ceramic rod is taken out, the melt temperature is increased to 1470℃ for pouring, and a nickel-based high-temperature alloy ingot with low rare earth dross content is obtained.

[0083] According to chemical composition analysis, the Y content in the alloy ingot prepared by the embodiment is about 0.022%, and it should be noted that the rare earth element Y will react with the inclusion elements O, N, and S to form rare earth oxides and rare earth sulfides, etc. during the refining process. After complex treatment, the adsorbing impurity structure adsorbs the rare earth oxides and rare earth sulfides in the melt, thereby reducing the content of Y element in the melt. The Y content in the alloy ingot prepared by the existing conventional process (i.e., using a filter screen to filter out inclusions and dross and other suspended matters) is about 0.029%.

[0084] In addition, the dross on the surface of the melt during the remelting process of the embodiment is compared with that of the conventional process (i.e., the conventional process is to use a filter screen to filter out inclusions and dross and other suspended matters), as shown in Figure 1 , wherein the dross surface ratio of the alloy prepared by the embodiment during the remelting process is about 1.5% (see Figure 1 (a) shown), and the dross surface ratio of the alloy prepared by the conventional process is about 13.0% (see Figure 1 (b) shown). From Figure 1It can be obviously seen that the process of the embodiment can significantly reduce the rare earth dross content. Here, the rare earth dross and other inclusions existing in the material can seriously affect the fatigue performance of the material. These inclusions can cause stress concentration and promote the generation of fatigue cracks, resulting in material damage.

[0085] Embodiment 2

[0086] In this embodiment, a nickel-based superalloy with low rare earth dross content is prepared. Specifically, a 25 kg vacuum induction furnace is used to prepare a master alloy ingot, and 19 kg of raw materials are fed. The main steps are as follows:

[0087] 1) A high-alumina ceramic rod is prepared as an adsorption and impurity removal structure by isostatic pressing + sintering process, with a size of about φ50x200mm 3 , and a groove about 10mm deep is polished around the upper end about 50mm away from the upper end to fix it on the temperature measuring rod.

[0088] In this embodiment, the specific raw materials of the adsorption and impurity removal structure in this step are: high-alumina ceramic powder, the mass fraction of alumina in the ceramic powder is ≥80wt%, and the particle size is ≤400 mesh. The specific preparation steps are: the ceramic powder is put into the mold, and the isostatic pressing process with a pressure of 300MPa for about 6min is used to ensure the shaping. Then it is put into a sintering furnace for sintering, and the sintering process is: 800℃x4h+1500℃x2h, after the end, it is taken out after the furnace is cooled to below 400℃, and the adsorption and impurity removal structure with a porous microstructure is obtained; wherein the pore size of the porous microstructure is 10-100μm. The adsorption and impurity removal structure is a rod structure. A fixing groove is provided on the adsorption and impurity removal structure; wherein the fixing groove is used to fix the temperature measuring rod. The longitudinal section of the adsorption and impurity removal structure is designed as an inverted trapezoid.

[0089] 2) Al-Y is used as the main raw material for adding rare earth, and the batching point is Y: 0.03wt%, and then it is wrapped with nickel foil after weighing.

[0090] 3) The raw materials are proportioned according to Table 3.

[0091] Table 3 Chemical composition of the alloy prepared in this embodiment, wt%

[0092] C Cr Co W Mo Al Nb Y B Zr Ni 0.10 9.50 5.00 3.50 3.00 6.00 2.00 0.03 0.02 0.005 Bal.

[0093] This step is specifically: first, the cobalt, carbon, tungsten, molybdenum, niobium, chromium, and nickel are sequentially fed into the crucible, and then vacuum induction melting is performed. After the alloy is liquefied and clear, high-temperature refining (1480-1550℃) is performed. After the high-temperature refining is completed, aluminum, boron, and zirconium are added to the melt. Then, the low-temperature refining stage (the surface temperature of the melt is about 1380-1420℃) is entered, the second raw material Al-Y is added to the melt, and 2min electromagnetic stirring (alloying) is performed to ensure uniform composition.

[0094] 4) Fix the adsorbing impurity structure on the temperature measuring rod with iron wire, and close the top charging turret, and vacuumize to below 1.0 Pa.

[0095] Open the top charging plug valve, close the vacuum pump unit, and fill argon until the vacuum gauge shows about 0.04 MPa, then extend the adsorbing impurity structure into the furnace body until it just contacts the liquid surface, hover for about 2 min, and then slowly immerse into the melt until the exposed part is about 1 / 3 of the total length of the ceramic rod, and the immersion process lasts for about 2 min.

[0096] 5) At the holding temperature of 1380-1420℃, sequentially perform low-temperature refining (2 min), power-off, stirring (stir for 2 min), reheat to the holding temperature before power-off, and so on for a total of 4 times, so that the melt is fully alloyed and has certain fluidity in the crucible. If the alloy liquid surface solidification phenomenon occurs during the process, the heating power can be increased to melt the surface solidified alloy.

[0097] In addition, under electromagnetic induction, the flow mode of the melt in the center of the crucible is from bottom to top.

[0098] 6) After the last stirring is completed, slowly take out the ceramic rod, and the taking-out time is about 2 min. This process should avoid too fast taking-out speed to cause thermal cracking of the ceramic rod and falling into the alloy liquid.

[0099] 7) After the ceramic rod is taken out, the melt temperature is increased to 1440℃ for pouring, and a low-rare earth float slag content nickel-based high-temperature alloy ingot can be obtained.

[0100] According to the chemical composition analysis, the Y content in the alloy ingot prepared by the embodiment is about 0.020%, and the Y content in the alloy ingot prepared by the conventional process (the conventional process is to filter out inclusions and float slag and other suspended matters) is about 0.022%.

[0101] The scheme of the embodiment compares the melt surface float slag during remelting with the conventional process, as shown in Figure 2 , wherein the float slag surface ratio of the alloy prepared by the embodiment during remelting is about 0.8% (see Figure 2 (a) figure), and the float slag surface ratio of the alloy prepared by the conventional process is about 7.5% (see Figure 2 (b) figure). It can be clearly seen from Figure 2 that the process of the embodiment can significantly reduce the rare earth float slag content.

[0102] The above is only a preferred embodiment of the present application, and does not limit the present application in any form. Any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present application still falls within the scope of the technical solution of the present application.

Claims

1. A method of producing a low rare earth dross content nickel-base superalloy, characterized by, It comprises the following steps: 1) preparing raw materials according to the chemical composition requirements of the nickel-based superalloy; wherein, the raw materials include first raw materials and second raw materials; wherein, the second raw materials are used to provide rare earth elements; the first raw materials are used to provide other elements except rare earth elements; 2) first, smelting and high-temperature refining are performed on the first raw materials; then, when low-temperature refining is performed, the second raw materials are added to the melt, after alloying, the adsorption impurity-removing structure is immersed in the melt, and at least one compound treatment is performed, so that the adsorption impurity-removing structure adsorbs rare earth oxides and rare earth sulfides in the melt, purifies the melt, and reduces the content of rare earth dross in the melt; wherein, each time the compound treatment comprises sequentially performing low-temperature refining, power-off, and stirring treatment; wherein, the material of the adsorption impurity-removing structure is any one of magnesia ceramic material, alumina ceramic material, and composite ceramic material of magnesia and alumina; wherein, the surface of the adsorption impurity-removing structure is microporous structure; the pore size of the microporous structure is 10-100 μm; wherein, the preparation method of the adsorption impurity-removing structure comprises the following steps: placing ceramic powder into a mold, performing isostatic pressing forming treatment to obtain a blank, and performing sintering treatment on the blank to obtain the adsorption impurity-removing structure; wherein, if the flow mode of the melt at the center of the crucible under electromagnetic induction is from top to bottom, the longitudinal section of the adsorption impurity-removing structure is designed as a right trapezoid; if the flow mode of the melt at the center of the crucible under electromagnetic induction is from bottom to top, the longitudinal section of the adsorption impurity-removing structure is designed as an inverted trapezoid; 3) taking out the adsorption impurity-removing structure from the melt, performing pouring treatment on the melt, and obtaining a nickel-based superalloy with low rare earth dross content.

2. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 1, characterized in that, The mass fraction of magnesia in the magnesia ceramic material is ≥80 wt%.

3. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 1, characterized in that, The mass fraction of alumina in the alumina ceramic material is ≥80 wt%.

4. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 1, characterized in that, The composite ceramic material of magnesia and alumina includes magnesia, alumina, and silicon dioxide; wherein, the mass fraction of magnesia is ≥80 wt%, the mass fraction of alumina is 10-15 wt%, and the mass fraction of silicon dioxide is 1-5 wt%.

5. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 1, characterized in that, In the preparation method of the adsorption impurity-removing structure: The particle size of the ceramic powder is ≤400 mesh.

6. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 1, characterized in that, In the preparation method of the adsorption impurity-removing structure: The ceramic powder is selected from one or both of magnesia ceramic powder and alumina ceramic powder; wherein, the mass fraction of magnesia in the magnesia ceramic powder is ≥80 wt%, and the mass fraction of alumina in the alumina ceramic powder is ≥80 wt%.

7. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 1, characterized in that, In the preparation method of the adsorption impurity-removing structure: The pressure of the isostatic pressing forming treatment is 200-600 MPa; the time of the isostatic pressing forming treatment is 2-10 min.

8. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 1, characterized in that, In the sintering treatment step: first, the blank is heated to a temperature of 800±100 ℃ for low-temperature sintering treatment for 3.5-4.5 h, and then heated to 1500±100 ℃ for high-temperature sintering for 2-2.5 h; after cooling, the adsorption impurity-removing structure with physical adsorption dross effect is obtained.

9. The method of claim 1, wherein the nickel-based superalloy has a low content of rare earth dross, and the method comprises the following steps: 1) preparing a first raw material and a second raw material; 2) vacuum induction melting the first raw material and the second raw material to obtain a molten metal; 3) stirring the molten metal; and 4) removing inclusions from the molten metal by using an adsorption structure. The adsorption structure is a rod structure; and / or The adsorption structure is provided with a fixing groove; wherein the fixing groove is used to fix the top charging rod or the temperature measuring rod.

10. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 1, characterized in that, The chemical composition of the nickel-based superalloy is as follows in terms of weight percentage: Carbon: 0.03-0.15wt%, chromium: 8.00-10.00wt%, cobalt: 4.00-6.00wt%, tungsten: 2.00-5.00wt%, molybdenum: 2.50-3.50wt%, aluminum: 5.50-6.00wt%, niobium: 1.85-2.30wt%, yttrium: 0.005-0.050wt%, boron: 0.001-0.035wt%, zirconium: 0.001-0.007wt%, rhenium: 0-0.2wt%, oxygen: 0-0.002wt%, nitrogen: 0-0.002wt%, sulfur: 0-0.002wt%, and the balance being nickel.

11. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 10, characterized in that, The content of oxygen, nitrogen and sulfur in the nickel-based superalloy is ≤20ppm.

12. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 1, characterized in that, The nickel-based superalloy is an equiaxed crystal nickel-based superalloy.

13. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 1, characterized in that, In the step 1), the second raw material comprises an Al-Y intermediate alloy. In the step 1), the first raw material comprises carbon, chromium, cobalt, tungsten, molybdenum, aluminum, niobium, boron, zirconium, and nickel.

14. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 1, characterized in that, In the step 1), the first raw material further comprises rhenium.

15. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 14, characterized in that, In the step 2), 16. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 1, wherein Before vacuum induction melting the first raw material, the cobalt, carbon, tungsten, molybdenum, niobium, chromium, and nickel are sequentially distributed in the crucible, and then melting and high-temperature refining are performed; wherein, after the high-temperature refining is completed, the aluminum, boron, and zirconium are added to the melt, and then low-temperature refining is performed. In the step 2), when the first raw material further comprises rhenium, wherein, after the cobalt, carbon, tungsten, molybdenum, niobium, chromium, and nickel are completely refined, the rhenium is added to the melt before high-temperature refining.

17. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 16, characterized in that, In the step 2), the temperature of the high-temperature refining is 1480-1550℃.

18. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 16, wherein In the step 2), 19. The method of producing a low-rare earth dross content nickel-base superalloy according to claim 1, wherein The temperature of the low-temperature refining is 1380-1420℃; and / or In each complex treatment including low-temperature refining, power-off, and stirring treatment, the time of the low-temperature refining is 5-30min; and / or The adsorption structure is slowly immersed in the melt after being baked on the surface of the melt for at least 1min; And / or The depth of the adsorption structure immersed in the melt is 1 / 2-2 / 3 of the depth of the melt; and / or The volume of the adsorption structure immersed in the melt is 1 / 5-1 / 4 of the volume of the melt; and / or The adsorption structure is immersed in the melt from the center position of the liquid surface. In the step 2), 20. The method of producing a low rare earth dross content nickel-base superalloy according to any one of claims 1 to 19, characterized in that, If the weight of the raw material is ≤10kg, the number of complex treatments is 1-2, and the time of each stirring treatment is 0.5-2min; If the weight of the raw material is greater than 10kg and less than or equal to 50kg, the number of complex treatments is 1-3, and the time of each stirring treatment is 1-3min; ​ If the weight of the raw material is greater than 50 kg and less than or equal to 200 kg, the number of times of the composite treatment is 3-5, and the time of each stirring treatment is 2-4 min; If the weight of the raw material is greater than 200 kg and less than or equal to 500 kg, the number of times of the composite treatment is 4-7, and the time of each stirring treatment is 3-6 min; If the weight of the raw material is greater than 500 kg, the time of each stirring treatment is ≥ 5 min.

21. A low rare earth dross content nickel-base superalloy characterized by, The chemical composition of the nickel-based superalloy is as follows in terms of weight percentage: carbon: 0.03-0.15 wt%, chromium: 8.00-10.00 wt%, cobalt: 4.00-6.00 wt%, tungsten: 2.00-5.00 wt%, molybdenum: 2.50-3.50 wt%, aluminum: 5.50-6.00 wt%, niobium: 1.85-2.30 wt%, yttrium: 0.005-0.050 wt%, boron: 0.001-0.035 wt%, zirconium: 0.001-0.007 wt%, rhenium: 0-0.2 wt%, oxygen: 0-0.002 wt%, nitrogen 0-0.002 wt%, sulfur 0-0.002 wt%, and the balance being nickel; wherein the dross content in the nickel-based superalloy is ≤ 3 wt%. The low-rare earth dross content nickel-based superalloy is prepared by the method of any one of claims 1-20.

22. The low rare earth dross content nickel-base superalloy of claim 21, wherein, The sum of the contents of oxygen, nitrogen, and sulfur in the nickel-based superalloy is ≤ 20 ppm.

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