Vacuum melting purification method for high-temperature alloy

Abstract

The invention relates to the technical field of high-temperature alloy smelting, and particularly discloses a high-temperature alloy vacuum smelting purification method which comprises the steps of S1, raw material crushing, S2, vacuum heat treatment, S3, smelting, S4, slag removal, S5, slag remelting, S6, slag filtering, S7, repeating the steps S3-S6 and S8, component detection. By optimizing metal raw material control, slag treatment optimization, slag remelting and filtering technologies, impurities and impure substances in the alloy can be effectively removed, the purity of the alloy is improved, the purification method can ensure that the impurities and bad substances in the alloy are effectively removed, and therefore defects in the alloy are reduced, and the quality and reliability of products are improved; the mechanical property, the heat resistance and the corrosion resistance of the alloy can be improved due to improvement of the purity of the alloy, so that the application range and the performance advantages of the alloy are increased, the waste rate and the energy consumption in the production process can be reduced by reducing unnecessary impurities in the alloy, and the production cost is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of high-temperature alloy smelting, and in particular relates to a method for vacuum melting and purification of high-temperature alloys. Background Art

[0002] Harmful impurity elements such as oxygen, nitrogen, sulfur and metal impurities have extremely adverse effects on the mechanical properties, process properties, and high-temperature oxidation corrosion resistance of metal materials, especially nickel-based high-temperature alloys. Therefore, how to reduce the content of harmful impurity elements in nickel-based high-temperature alloys has always been the focus of research and development of nickel-based high-temperature alloy smelting technology.

[0003] In the prior art, CN112538577B relates to a rare earth element control method for high-temperature alloy purification smelting, in which the designed addition amount of rare earth elements is calculated by an empirical formula and added in a specific order of addition. The control method can achieve the effect of deep purification smelting and precise control of rare earth content according to actual needs. By controlling the addition method of rare earth elements, the degree of alloying of rare earth elements with alloy matrix elements can be guaranteed, and the slag content during the remelting of rare earth element-containing master alloy can be effectively reduced, the purity of the alloy can be improved, and the quality of castings can be improved. The present invention is suitable for the smelting of most nickel-based high-temperature alloy master alloys. While improving the degree of alloy purification, the rare earth element content in the alloy can be accurately controlled, and the slag content during the secondary remelting of the master alloy can be effectively reduced, which greatly improves the quality of the master alloy and has significant economic benefits.

[0004] CN108546834B relates to a method for purifying and smelting a nickel-based high-temperature alloy master alloy, and the steps are as follows: (1) subjecting a metal raw material to hydrochloric acid and ultrasonic treatment; preparing a CaO-CaF2 pre-melted slag; uniformly mixing the pre-melted slag with pure nickel powder and pressing into blocks; (2) placing the raw material and the pressed blocks into a crucible together and evacuating the vacuum; adding C, Nb, Ti, and Al after melting; filling with argon gas, adding B and Zr until the alloy liquid is melted again and then pouring into a steel mold to obtain a high-temperature alloy ingot; removing the oxide scale and riser of the ingot to obtain a high-temperature alloy concentrate; (3) placing the concentrate into a copper crucible; evacuating the vacuum, melting, and rapidly solidifying to obtain a high-temperature alloy master alloy. The invention performs slag refining during vacuum induction melting, and has low sulfur and phosphorus contents; the copper crucible can avoid the crucible from polluting the alloy melt; the magnetic levitation can promote the floating of non-metallic inclusions; the oxygen and nitrogen contents are low, thereby reducing the number of non-metallic inclusions formed during the cooling and solidification of the alloy liquid; the existing mature melting equipment is used, and the operation is convenient.

[0005] CN115948657A relates to a purification recovery method, which comprehensively utilizes vacuum refining, air blowing refining, slag washing treatment, overheating treatment, filtration treatment, decompression purification, and coordinated purification treatment, which fully and effectively guarantees the cleanliness of the returned alloy after treatment, and smelting under pressure atmosphere reduces the volatilization loss of useful elements and the crucible reaction of active elements such as hafnium, aluminum, and titanium, thereby ensuring the accuracy of the alloy composition. Overheating treatment and gas stirring also further promote the homogenization and organization refinement of the alloy composition, and reduce the generation of harmful aggregates. The quality of the returned material is significantly improved, and the quality risk of the returned material is reduced, especially for the treatment of alloys containing hafnium, high aluminum, high chromium, etc.

[0006] However, the existing technology does not solve the problem that the inclusion of oxides and nitrides formed by oxygen, nitrogen and other alloying elements in nickel-based high-temperature alloys will become crack initiation sources and rapid expansion channels, seriously reducing core mechanical properties such as durability, creep and fatigue. In order to solve the problem that the impurities contained in high-temperature alloys during vacuum melting affect their quality, this patent proposes a method for vacuum melting purification of high-temperature alloys to solve the above problems. Summary of the invention

[0007] The object of the present invention is to provide a method for purifying high-temperature alloys by vacuum melting, so as to solve the problem that the quality of high-temperature alloys is affected by impurities contained in the vacuum melting.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] The method for vacuum melting and purification of high temperature alloys comprises:

[0010] S1. Raw material crushing: using alloy raw material cutting machine or crusher, the alloy material is divided into uniform small pieces, so that the particle size of the alloy material is controlled below 100 mesh;

[0011] S2, vacuum heat treatment, placing the alloy material into a crucible 1 of a vacuum melting furnace, pumping the melting furnace to a high vacuum state, and performing vacuum preheating treatment;

[0012] S3, melting, heating to 2000℃~2200℃, making the alloy raw materials completely melted and fully mixed;

[0013] S4, slag removal, set the slag trough and slag mouth with an inclination angle of 30° to 50° so that the slag can be discharged smoothly, use cyclone separation or centrifugal separation method to separate the melted alloy from the slag, use inert gas flow to assist slag discharge, use slag spoon or vacuum slag suction device to quickly and effectively remove the slag to obtain partially pure alloy one;

[0014] S5, slag remelting, collecting the slag produced during the smelting step S4 under vacuum conditions, placing it in a second crucible, heating the slag using a resistance furnace or an induction heating furnace, and separating the heavy metal impurities in the slag by dumping or using a centrifuge;

[0015] S6, slag filtering, selecting a ceramic filter, installing the ceramic filter at the outlet or pouring port of the crucible 2 in step S5, ensuring that the slag passes through the ceramic filter before flowing out, filtering out impurities in the slag through the ceramic filter, and obtaining pure alloy 2;

[0016] S7, fusing the pure alloy 2 in S6 with the pure alloy 1 in S4, and repeating the steps of S3, S4, S5 and S6 to obtain a pure alloy;

[0017] S8. Composition testing: Analyze and test the pure alloy in S7, including chemical analysis and microstructural observation.

[0018] Preferably, the high vacuum state in S2 is 10 -2 ~10 -4 Pa, vacuum heating method is resistance heating or induction heating.

[0019] Preferably, the vacuum preheating temperature in S2 ranges from 800° C. to 1200° C., and the processing time is 1 to 2 hours.

[0020] Preferably, the slag heating temperature in S5 is between 1400°C and 1600°C.

[0021] Preferably, the crucible 2 in S5 comprises a stainless steel crucible or a ceramic crucible.

[0022] Preferably, the pore size of the ceramic filter in S6 is between 10 and 100 microns, and the material is a high-temperature resistant and chemically stable ceramic material, and the ceramic material includes aluminum oxide or silicon carbide.

[0023] Preferably, the component of the inert gas flow is argon.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) The present invention can effectively remove impurities and impure substances in the alloy and improve the purity of the alloy by optimizing metal raw material control, slag treatment optimization, slag remelting and filtration technology. The purification method can ensure that impurities and undesirable substances in the alloy are effectively removed, thereby reducing defects in the alloy and improving product quality and reliability. The improvement of alloy purity will lead to the improvement of the alloy's mechanical properties, heat resistance and corrosion resistance, thereby increasing the application range and performance advantages of the alloy.

[0026] (2) The present invention can reduce the scrap rate and energy consumption in the production process by reducing unnecessary impurities in the alloy, thereby reducing production costs; the above purification method can improve the operating efficiency and process stability in the production process, and reduce production failures and downtime caused by impurities and impure substances. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The present invention is a flow chart of the method for vacuum melting and purification of high-temperature alloys. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] Embodiment 1:

[0030] See also Figure 1 As shown, the method for vacuum melting and purification of high temperature alloy comprises:

[0031] S1. Crush the raw materials. Use an alloy raw material cutting machine to cut the alloy material into uniform small pieces, so that the particle size of the alloy material is controlled below 100 mesh. The proportions of the components in the alloy are 30% nickel, 12% chromium, 0.5% niobium, 3% tungsten, 3% titanium, 1% aluminum, 0.1% boron, 0.1% carbon, and the balance is iron;

[0032] S2, vacuum heat treatment, put the alloy material into the crucible of the vacuum melting furnace, pump the melting furnace to a high vacuum state, and control the pressure to 10 -3 Pa, vacuum preheating treatment, vacuum heating method is resistance heating, heating temperature is 1100℃, treatment time is 2 hours;

[0033] S3, melting, heating to 2100°C to completely melt the alloy raw materials and mix them thoroughly;

[0034] S4, slag removal, set the slag trough and slag mouth with an inclination angle of 50° so that the slag can be discharged smoothly, use cyclone separation to separate the melted alloy from the slag, use argon gas flow to assist slag discharge, use a vacuum slag suction device to quickly and effectively remove the slag to obtain partially pure alloy 1;

[0035] S5, slag remelting, using a ceramic crucible to collect the slag produced during the smelting step S4 under vacuum conditions, using a resistance furnace to heat the slag at a heating temperature of 1600° C., and separating the heavy metal impurities in the slag by dumping;

[0036] S6, slag filtration, select a ceramic filter with a pore size of 70 microns, install the ceramic filter at the pouring port of the crucible 2, ensure that the slag passes through the ceramic filter before flowing out, filter out impurities in the slag through the ceramic filter, and obtain pure alloy 2;

[0037] S7, fusing the pure alloy 2 in S6 with the pure alloy 1 in S4, and repeating the steps of S3, S4, S5 and S6 to obtain a pure alloy;

[0038] S8. Composition testing: Analyze and test the pure alloy in S7, including chemical analysis and microstructural observation.

[0039] Specifically, chemical analysis includes:

[0040] Use mass spectrometer, gas chromatograph and other equipment to analyze the gas composition in the vacuum furnace to ensure the stability of the inert atmosphere;

[0041] Metal composition analysis: Use spectrum analyzer, X-ray fluorescence spectrometer and other equipment to analyze the composition of smelted metal samples to ensure the accuracy and consistency of product alloy composition;

[0042] Slag analysis: chemical analysis and microstructural observation of the slag produced after smelting to evaluate the purity and component distribution of the slag;

[0043] The slag is sampled after smelting, ground, and dissolved or prepared into a sample solution suitable for analysis using inductively coupled plasma optical emission spectrometry.

[0044] Embodiment 2:

[0045] See also Figure 1 As shown, the method for vacuum melting and purification of high temperature alloy comprises:

[0046] S1. Crush the raw materials. Use an alloy raw material crusher to divide the alloy material into uniform small pieces, so that the particle size of the alloy material is controlled below 100 mesh. The proportions of the components in the alloy are 30% nickel, 12% chromium, 0.5% niobium, 3% tungsten, 3% titanium, 1% aluminum, 0.1% boron, 0.1% carbon, and the balance is iron;

[0047] S2, vacuum heat treatment, put the alloy material into the crucible of the vacuum melting furnace, pump the melting furnace to a high vacuum state, and control the pressure to 10 -3 Pa, vacuum preheating treatment, vacuum heating method is resistance heating, heating temperature is 1200℃, treatment time is 2 hours;

[0048] S3, melting, heating to 2200°C to completely melt the alloy raw materials and mix them thoroughly;

[0049] S4, slag removal, set the slag trough and slag mouth with an inclination angle of 30° so that the slag can be discharged smoothly, use the centrifugal separation method to separate the melted alloy from the slag, use argon gas flow to assist the slag discharge, use a slag spoon or a vacuum slag suction device to quickly and effectively remove the slag to obtain partially pure alloy one;

[0050] S5, slag remelting, using a ceramic crucible to collect the slag produced during the smelting process under vacuum conditions, using an induction heating furnace to heat the slag at a heating temperature of 1500°C, and using a centrifuge to separate heavy metal impurities in the slag;

[0051] S6, slag filtration, select a ceramic filter with a pore size of 80 microns, install the ceramic filter at the outlet of the crucible 2, ensure that the slag passes through the ceramic filter before flowing out, filter out impurities in the slag through the ceramic filter, and obtain pure alloy 2;

[0052] S7, fusing the pure alloy 2 in S6 with the pure alloy 1 in S4, and repeating the steps of S3, S4, S5 and S6 to obtain a pure alloy;

[0053] S8. Composition testing: Analyze and test the pure alloy in S7, including chemical analysis and microstructural observation.

[0054] Embodiment three:

[0055] See also Figure 1 As shown, the method for vacuum melting and purification of high temperature alloy comprises:

[0056] S1. Crushing the raw materials: using an alloy raw material crusher, the alloy material is divided into uniform small pieces, so that the particle size of the alloy material is controlled below 100 meshes, and the proportions of the components in the alloy are 35% nickel, 15% chromium, 0.5% niobium, 3% tungsten, 3% titanium, 1% aluminum, 0.1% boron, 0.1% carbon, and the balance is iron;

[0057] S2, vacuum heat treatment, put the alloy material into the crucible of the vacuum melting furnace, pump the melting furnace to a high vacuum state, and control the pressure to 10 -3 Pa, vacuum preheating treatment, vacuum heating method is resistance heating, heating temperature is 1100℃, treatment time is 2 hours;

[0058] S3, melting, heating to 2100°C to completely melt the alloy raw materials and mix them thoroughly;

[0059] S4, slag removal, set the slag trough and slag mouth with an inclination angle of 50° so that the slag can be discharged smoothly, use the centrifugal separation method to separate the melted alloy from the slag, use argon gas flow to assist the slag discharge, use the vacuum slag suction device to quickly and effectively remove the slag, and obtain partially pure alloy one;

[0060] S5, slag remelting, using a ceramic crucible to collect the slag produced during the smelting process under vacuum conditions, using a resistance furnace to heat the slag at a heating temperature of 1600°C, and using a centrifuge to separate heavy metal impurities in the slag;

[0061] S6, slag filtration, select a ceramic filter with a pore size of 70 microns, install the ceramic filter at the pouring port of the crucible 2, ensure that the slag passes through the ceramic filter before flowing out, filter out impurities in the slag through the ceramic filter, and obtain pure alloy 2;

[0062] S7, fusing the pure alloy 2 in S6 with the pure alloy 1 in S4, and repeating the steps of S3, S4, S5 and S6 to obtain a pure alloy;

[0063] S8. Composition testing: Analyze and test the pure alloy in S7, including chemical analysis and microstructural observation.

[0064] Embodiment 4:

[0065] See also Figure 1 As shown, the method for vacuum melting and purification of high temperature alloy comprises:

[0066] S1. Crush the raw materials. Use an alloy raw material cutting machine to cut the alloy material into uniform small pieces, so that the particle size of the alloy material is controlled below 100 mesh. The proportions of the components in the alloy are 30% nickel, 12% chromium, 0.5% niobium, 3% tungsten, 3% titanium, 1% aluminum, 0.1% boron, 0.1% carbon, and the balance is iron;

[0067] S2, vacuum heat treatment, put the alloy material into the crucible of the vacuum melting furnace, pump the melting furnace to a high vacuum state, and control the pressure to 10 -3 Pa, vacuum preheating treatment, vacuum heating method is resistance heating, heating temperature is 1200℃, treatment time is 2 hours;

[0068] S3, melting, heating to 2200°C to completely melt the alloy raw materials and mix them thoroughly;

[0069] S4, slag removal, set the slag trough and slag mouth with an inclination angle of 45° so that the slag can be discharged smoothly, use cyclone separation to separate the melted alloy from the slag, use argon gas flow to assist slag discharge, use a vacuum slag suction device to quickly and effectively remove the slag to obtain partially pure alloy one;

[0070] S5, slag remelting, using a ceramic crucible to collect the slag produced during the smelting process under vacuum conditions, using an induction heating furnace to heat the slag at a heating temperature of 1500°C, and using a centrifuge to separate heavy metal impurities in the slag;

[0071] S6, slag filtration, select a ceramic filter with a pore size of 80 microns, install the ceramic filter at the outlet of the crucible 2, ensure that the slag passes through the ceramic filter before flowing out, filter out impurities in the slag through the ceramic filter, and obtain pure alloy 2;

[0072] S7, fusing the pure alloy 2 in S6 with the pure alloy 1 in S4, and repeating the steps of S3, S4, S5 and S6 to obtain a pure alloy;

[0073] S8. Composition testing: Analyze and test the pure alloy in S7, including chemical analysis and microstructural observation.

[0074] Embodiment five:

[0075] See also Figure 1 As shown, the method for vacuum melting and purification of high temperature alloy comprises:

[0076] S1. Crush the raw materials. Use an alloy raw material cutting machine to cut the alloy material into uniform small pieces, so that the particle size of the alloy material is controlled below 100 mesh. The proportions of the components in the alloy are 30% nickel, 12% chromium, 0.5% niobium, 3% tungsten, 3% titanium, 1% aluminum, 0.1% boron, 0.1% carbon, and the balance is iron;

[0077] S2, vacuum heat treatment, put the alloy material into the crucible of the vacuum melting furnace, pump the melting furnace to a high vacuum state, and control the pressure to 10 -3 Pa, vacuum preheating treatment, vacuum heating method is resistance heating, heating temperature is 1200℃, treatment time is 2 hours;

[0078] S3, melting, heating to 2200°C to completely melt the alloy raw materials and mix them thoroughly;

[0079] S4, slag removal, set the slag trough and slag mouth with an inclination angle of 40° so that the slag can be discharged smoothly, use the centrifugal separation method to separate the melted alloy from the slag, use argon gas flow to assist the slag discharge, use the slag spoon to quickly and effectively remove the slag to obtain partially pure alloy 1;

[0080] S5, slag remelting, using a ceramic crucible to collect the slag produced during the smelting process under vacuum conditions, using a resistance furnace to heat the slag at a heating temperature of 1600°C, and using a centrifuge to separate heavy metal impurities in the slag;

[0081] S6, slag filtration, select a ceramic filter with a pore size of 80 microns, install the ceramic filter at the outlet of the crucible 2, ensure that the slag passes through the ceramic filter before flowing out, filter out impurities in the slag through the ceramic filter, and obtain pure alloy 2;

[0082] S7, fusing the pure alloy 2 in S6 with the pure alloy 1 in S4, and repeating the steps of S3, S4, S5 and S6 to obtain a pure alloy;

[0083] S8. Composition testing: Analyze and test the pure alloy in S7, including chemical analysis and microstructural observation.

[0084] Embodiment six:

[0085] See also Figure 1 As shown, the method for vacuum melting and purification of high temperature alloy comprises:

[0086] S1. Crush the raw materials. Use an alloy raw material cutting machine to cut the alloy material into uniform small pieces, so that the particle size of the alloy material is controlled below 100 mesh. The proportions of the components in the alloy are 30% nickel, 12% chromium, 0.5% niobium, 3% tungsten, 3% titanium, 1% aluminum, 0.1% boron, 0.1% carbon, and the balance is iron;

[0087] S2, vacuum heat treatment, put the alloy material into the crucible of the vacuum melting furnace, pump the melting furnace to a high vacuum state, and control the pressure to 10 -3 Pa, vacuum preheating treatment, vacuum heating method is resistance heating, heating temperature is 1200℃, treatment time is 2 hours;

[0088] S3, melting, heating to 2200°C to completely melt the alloy raw materials and mix them thoroughly;

[0089] S4, slag removal, set the slag trough and slag mouth with an inclination angle of 50° so that the slag can be discharged smoothly, use the centrifugal separation method to separate the melted alloy from the slag, use argon gas flow to assist the slag discharge, use the slag spoon to quickly and effectively remove the slag to obtain partially pure alloy 1;

[0090] S5, slag remelting, using a ceramic crucible to collect the slag produced during the smelting process under vacuum conditions, using an induction heating furnace to heat the slag at a heating temperature of 1500° C. and separating the heavy metal impurities in the slag by dumping;

[0091] S6, slag filtration, select a ceramic filter with a pore size of 70 microns, install the ceramic filter at the outlet of the crucible 2, ensure that the slag passes through the ceramic filter before flowing out, filter out impurities in the slag through the ceramic filter, and obtain pure alloy 2;

[0092] S7, fusing the pure alloy 2 in S6 with the pure alloy 1 in S4, and repeating the steps of S3, S4, S5 and S6 to obtain a pure alloy;

[0093] S8. Composition testing: Analyze and test the pure alloy in S7, including chemical analysis and microstructural observation.

[0094] Comparative Example:

[0095] The method for vacuum melting and purification of high temperature alloys comprises:

[0096] S1. Crush the raw materials. Use an alloy raw material crusher to divide the alloy material into uniform small pieces, so that the particle size of the alloy material is controlled below 100 mesh. The proportions of the components in the alloy are 30% nickel, 12% chromium, 0.5% niobium, 3% tungsten, 3% titanium, 1% aluminum, 0.1% boron, 0.1% carbon, and the balance is iron;

[0097] S2, vacuum heat treatment, put the alloy material into the crucible of the vacuum melting furnace, pump the melting furnace to a high vacuum state, and control the pressure to 10 -3 Pa, vacuum preheating treatment, vacuum heating method is resistance heating, heating temperature is 1200℃, treatment time is 2 hours;

[0098] S3, melting, heating to 2200°C to completely melt the alloy raw materials and mix them thoroughly;

[0099] S4, filtering, select a ceramic filter with a pore size of 80 microns, install the ceramic filter at the outlet of the second crucible, ensure that the alloy passes through the ceramic filter before flowing out, filter out impurities in the slag through the ceramic filter, and obtain a pure alloy;

[0100] S5. Composition testing: analyzing and testing the pure alloy obtained in S4, including chemical analysis and microstructural observation.

[0101] The test steps are as follows:

[0102] The samples in Example 1 and Example 4 were selected for microstructure observation:

[0103] Sample preparation: Prepare the slag samples after sampling by grinding;

[0104] Microstructure observation: Observation was performed using optical microscope and scanning electron microscope (SEM) equipment;

[0105] Structural characteristics: Observe the microstructural characteristics such as grain morphology, grain boundary, pore structure, etc. of the samples in Example 1 and Example 4;

[0106] Particle shape: It was observed that the sample alloy materials in Example 1 and Example 4 had a granular or flaky structure, and the particle size was uniform.

[0107] Surface morphology: The surfaces of the sample alloy materials in Example 1 and Example 4 are smooth and have no obvious cracks or particle accumulation.

[0108] Particle distribution: The sample particles in Example 1 and Example 4 are evenly distributed without obvious aggregation, and the alloy material has high stability.

[0109] Taking a sample from the smelted slag, grinding the sample, and dissolving or preparing it into a sample solution suitable for analysis by inductively coupled plasma optical emission spectrometry or atomic absorption spectrometry;

[0110] Analyze the content of main elements and impurity elements in the sample liquid:

[0111] The result is:

[0112] Main element analysis: Fe, Cr, Ni, Co;

[0113] Impurity element analysis: SiO2, Al2O3, MgO;

[0114] The purity of the alloys in all the above embodiments and comparative examples was tested, and the data are as follows:

[0115] Example 1: Alloy composition 99.95%;

[0116] Example 2: alloy composition 99.72%;

[0117] Example 3: alloy composition 99.84%;

[0118] Example 4: alloy composition 99.96%;

[0119] Example 5: alloy composition 99.89%;

[0120] Example 6: alloy composition 99.81%;

[0121] Comparative example: alloy composition 96.32%.

[0122] From the above, we can see that by optimizing metal raw material control, slag treatment optimization, slag remelting and filtration technology, impurities and impure substances in the alloy can be effectively removed and the purity of the alloy can be improved. The purification method can ensure that impurities and undesirable substances in the alloy are effectively removed, thereby reducing defects in the alloy and improving product quality and reliability; the improvement of alloy purity will lead to the improvement of the alloy's mechanical properties, heat resistance and corrosion resistance, thereby increasing the application range and performance advantages of the alloy;

[0123] By reducing unnecessary impurities in the alloy, the scrap rate and energy consumption in the production process can be reduced, thereby reducing production costs; the above purification method can improve the operating efficiency and process stability in the production process, and reduce production failures and downtime caused by impurities and impure substances.

[0124] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for vacuum melting and purification of high temperature alloys, characterized in that: include: S1. Raw material crushing: using alloy raw material cutting machine or crusher, the alloy material is divided into uniform small pieces, so that the particle size of the alloy material is controlled below 100 mesh; S2, vacuum heat treatment, placing the alloy material into a crucible 1 of a vacuum melting furnace, pumping the melting furnace to a high vacuum state, and performing vacuum preheating treatment; S3, melting, heating to 2000℃~2200℃, making the alloy raw materials completely melted and fully mixed; S4, slag removal, set the slag trough and slag mouth with an inclination angle of 30° to 50° so that the slag can be discharged smoothly, use cyclone separation or centrifugal separation method to separate the melted alloy from the slag, use inert gas flow to assist slag discharge, use slag spoon or vacuum slag suction device to quickly and effectively remove the slag to obtain partially pure alloy one; S5, slag remelting, collecting the slag produced during the smelting step S4 under vacuum conditions, placing it in a second crucible, heating the slag using a resistance furnace or an induction heating furnace, and separating the heavy metal impurities in the slag by dumping or using a centrifuge; S6, slag filtering, selecting a ceramic filter, installing the ceramic filter at the outlet or pouring port of the crucible 2 in step S5, ensuring that the slag passes through the ceramic filter before flowing out, filtering out impurities in the slag through the ceramic filter, and obtaining pure alloy 2; S7, fusing the pure alloy 2 in S6 with the pure alloy 1 in S4, and repeating the steps of S3, S4, S5 and S6 to obtain a pure alloy; S8. Composition testing: Analyze and test the pure alloy in S7, including chemical analysis and microstructural observation.

2. The method for vacuum melting and purification of high temperature alloy according to claim 1, characterized in that: S2 medium and high vacuum state is 10 -2 ~10 -4 Pa, vacuum heating method is resistance heating or induction heating.

3. The method for vacuum melting and purification of high temperature alloy according to claim 1, characterized in that: The vacuum preheating temperature in S2 ranges from 800°C to 1200°C, and the processing time is 1 to 2 hours.

4. The method for vacuum melting and purification of high temperature alloy according to claim 1, characterized in that: The heating temperature of S5 slag is between 1400℃ and 1600℃.

5. The method for vacuum melting and purification of high temperature alloy according to claim 1, characterized in that: The crucible 2 in S5 includes a stainless steel crucible or a ceramic crucible.

6. The method for vacuum melting and purification of high temperature alloy according to claim 1, characterized in that: The pore size of the ceramic filter in S6 is between 10 and 100 microns, and the material is a high-temperature resistant and chemically stable ceramic material, and the ceramic material includes aluminum oxide or silicon carbide.

7. The method for vacuum melting and purification of high temperature alloy according to claim 1, characterized in that: The component of the inert gas flow is argon.

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