Triple preparation method of high-uniformity carbide GH4169 alloy

Abstract

The invention relates to a triple preparation method of a high-uniformity carbide GH4169 alloy, which adopts VIM + ESR + VAR triple smelting, and obtains an alloy melt with uniformly distributed oxides of Ce as a nucleation particle of a subsequent carbide by controlling a charging sequence and refining time. Slag with high oxide content is used in the subsequent ESR process, higher power and shallower insertion depth are used, it is guaranteed that the relatively low melting speed is kept under the higher power, and all Ce elements are promoted to form fine nucleation particles. In addition, larger water flow and He flow are kept in the VAR process, and alloy cooling and carbide nucleation are promoted. And finally, a high-uniformity GH4169 alloy cast ingot is prepared, the grade of carbides at all parts of a final bar is grade 1 (GB / T1499.6), and the grade of the purity is grade 1 (GB / T14999.5). According to the method, the carbide uniformity of GH4169 alloy bars and workpieces is greatly improved, and an excellent foundation is laid for preparing high-quality GH4169 alloy.

Description

Technical Field

[0001] The invention relates to the technical field of metal materials, and in particular to a triple preparation method of a high-uniform carbide GH4169 alloy. Background Art

[0002] Advanced aviation manufacturing technology is one of the important symbols of a country's scientific and technological level, military strength and comprehensive national strength. With the rapid development of aviation technology, facing the ever-increasing requirements of national defense construction, the new generation of aircraft must meet the stringent service requirements of core components of aviation engines such as turbine disks and blades, and adapt to the continuous improvement of engine thermal efficiency in the aerospace industry. The main parameter considered for improving the thermal efficiency of aviation engines is the turbine inlet temperature (TIT), that is, the temperature of the airflow entering the first stage of the turbine. Improving TIT is the direction of efforts of scientific researchers in various countries. At high temperatures, high-end alloy parts have increasingly higher requirements for the purity and uniformity of alloys.

[0003] Through unremitting efforts, our scientific research and engineering workers have greatly improved the purity of the alloy by improving raw materials, smelting equipment, smelting technology, etc. It is reported that the content of key impurity elements (oxygen, nitrogen and sulfur) of GH4169 alloy can be controlled within 7ppm, indicating that the smelting level of GH4169 alloy in my country has reached a relatively high level. But at the same time, the uniformity of the alloy still needs to be improved. The problem of carbide segregation on the axial surface after forging of Sanlian GH4169 alloy has always been one of the serious problems that plagued major high-temperature alloy manufacturers. A large number of carbides are streamlined and distributed along the axial direction, resulting in anisotropy of the mechanical properties of the alloy, and even causing the failure of the mechanical properties of the alloy parts at weak points.

[0004] At present, some practitioners increase the nitrogen content in the alloy to form carbide nucleation points, so that the carbides can be more evenly distributed. However, although this method promotes the uniform distribution of carbides to a certain extent, it also introduces new inclusions into the alloy, increasing the risk of alloy failure. In addition, since nitrides and carbides have the same crystal structure, they are very easy to be improperly controlled, resulting in multiple serious segregation of carbides and nitrides, which damages the mechanical properties of alloy parts.

[0005] Therefore, the present invention aims at the problem of uneven carbide distribution in Sanlian GH4169 alloy bars and products, optimizes the smelting process through theoretical analysis, and greatly improves the distribution uniformity of alloy carbides. Summary of the invention

[0006] The purpose of the present invention is to provide a triple preparation method for a high-uniform carbide GH4169 alloy to solve the problems of carbide streamline and easy segregation in the existing triple GH4169 alloy (VIM+ESR+VAR). The present invention provides a preparation process for a high-uniform carbide GH4169 alloy. Firstly, by controlling the raw materials, feeding sequence and refining time in the VIM process, low-density non-metallic oxides such as Al2O3 and MgO in the alloy melt are reduced to obtain a highly pure VIM melt. Subsequently, an appropriate amount of NiCe alloy is added in the final stage of VIM melting to form Ce oxides in the alloy melt. The density of these oxides is greater than that of low-density non-metallic inclusions such as Al2O3 and MgO, and they are less likely to segregate in the alloy melt and can be evenly distributed in the alloy melt to serve as nucleation sites for subsequent carbides. In the subsequent ESR process, a slag with a high oxide content is used, and a larger power and a shallower insertion depth are used to ensure a relatively low melting rate at a larger power, promoting all Ce elements to form fine nucleation sites. In addition, a larger water flow rate and He flow rate are maintained in the VAR process to promote the cooling of the alloy and carbide nucleation. Finally, a GH4169 alloy ingot with high uniformity is prepared.

[0007] To achieve the above object, the present invention provides the following technical solution: A triple preparation method for a high-uniform carbide GH4169 alloy, comprising the following steps:

[0008] Step 1: Prepare a high-quality high-aluminum-based preformed crucible or a brick-shaped crucible; the alumina content is greater than 90%, the refractoriness is greater than 1770 °C, the bulk density is greater than 3.2 g / cm3, and the apparent porosity is less than 40%;

[0009] Step 2: Prepare according to the component ratio: Ni, with a proportion of 51-55%; Cr with a proportion of 18-21%; C, with a proportion of 0.02-0.08%; Fe, with the balance; Mo with a proportion of 2.85-3.3%; Nb with a proportion of 4.5-5.4%. All raw materials are added through a continuous feeding hopper;

[0010] Step 3: After the leak rate before vacuum induction furnace melting is lower than 250 Pa / min, add the materials prepared in Step 2 in sequence: the bottom material is Ni, and the remaining materials are added in sequence; after all are added, stir for 10 min, adjust the temperature to between 1450 and 1550 °C for refining for 30-60 min, stir for 10 min every 10 minutes, and stir at least twice;

[0011] Step 4: Prepare according to the composition ratio with Ti accounting for 0.75 - 1.15%, Al accounting for 0.4 - 0.7%, and Ce accounting for 0.05 - 0.06%. After the refining is completed, adjust the melt temperature to the casting temperature between 1450 and 1500 °C, and then add the Ti, Al, and Ce raw materials in sequence. Stir for 10 min after adding Ti, 30 min after adding Al, and 10 min after adding Ce;

[0012] Step 5: Use vacuum casting. Use multi-stage baffles or filters in the casting launder for multi-stage filtration. Cool the ingot under vacuum for more than 240 min, and then break the vacuum and take out the ingot to obtain the GH4169 alloy VIM ingot;

[0013] Step 6: Use a grinding wheel to grind the GH4169 alloy VIM ingot with a single-sided grinding depth of more than 10 mm, and then perform ESR melting. Use a slag with CaF:Al2O3 = 7:3, and at the same time set the melting process to be controlled by melting rate / slag resistance. The melting rate range is 100 - 200 kg / h, and the slag resistance range is greater than 10 mOhm. After melting, the furnace cooling time is greater than 120 min, and then break the vacuum to obtain the GH4169 alloy ESR ingot;

[0014] Step 7: Use a lathe to turn the GH4169 alloy ESR ingot with a processing depth of more than 15 mm, and then perform VAR melting. The melting rate range is set to 100 - 150 kg / h, the water flow rate is set to 1500 L / min, and the cooling gas flow rate is 1200 ml / min. After melting, the furnace cooling time is greater than 120 min, and then break the vacuum to obtain the GH4169 alloy VAR ingot.

[0015] Preferably, the Ni is nickel plate, nickel beads or nickel ingot, the Cr is degassed chromium, the C is high-purity graphite block, the Fe is high-purity iron block, the Mo is Mo beads, and the Nb is pure Nb.

[0016] Preferably, in Step 2, first add 6 main alloying elements of Ni, Cr, C, Fe, Mo, and Nb in proportion, without adding Ti and Al elements.

[0017] Preferably, in the last step of Step 4, add Ti, Al, and Ce elements according to the composition ratio. After the refining is completed, adjust the melt temperature to the casting temperature between 1450 and 1500 °C, and then add the Ti, Al, and Ce raw materials in sequence. Stir for 10 min after adding Ti, 30 min after adding Al, and 10 min after adding Ce.

[0018] Preferably, in Step 6, the ESR melting uses a slag with CaF:Al2O3 = 7:3, and at the same time, the melting process is controlled by melt rate / slag resistance. The melt rate range is 100 - 200 kg / h, and the slag resistance range is greater than 10 mOhm.

[0019] Preferably, the slag in Step 6 is 70% CaF2 - 30% Al2O3 slag.

[0020] Preferably, the pouring pressure in Step 5 is ≤50 Pa.

[0021] Preferably, in Step 4, Ti is in the form of Ti blocks, Al is high - purity aluminum beans, and Ce is NiCe alloy.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: The GH4169 alloy is prepared by using a triple - melting method of VIM + ESR + VAR. In VIM, by reasonably changing the order of adding Al and the refining time, the content of gas impurities and inclusions in the alloy is reduced. Subsequently, NiCe alloy is added, providing a fine and uniform nucleating agent for the formation of carbides. In the ESR stage, a slag with a high oxide content is used, while reducing the melt rate and increasing the slag resistance to promote the uniform distribution of Ce oxides in the alloy melt and being wrapped by Al2O3. In the VAR stage, a water flow rate of more than 1200 L / min and a cooling gas flow rate of more than 1000 ml / min are used to rapidly cool the alloy, thereby preventing the growth and deformation of carbides. This method successfully prepares a GH4169 alloy ingot with ultra - uniform carbide distribution. After forging with any deformation amount, a GH4169 bar with ultra - uniform carbide distribution can be obtained, laying a good foundation for the preparation of high - quality aerospace key components. Description of the Drawings

[0023] Figure 1 The carbide morphology of Example 1;

[0024] Figure 2 The carbide morphology of Example 2

[0025] Figure 3 The carbide morphology of Example 3

[0026] Figure 4 The carbide morphology of Example 4

[0027] Figure 5 The carbide morphology of Example 5. Detailed Embodiments

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0029] Please refer to Figures 1-5 , the present invention provides a technical solution: using a 3-ton vacuum induction furnace, a 4-ton protective atmosphere electroslag furnace, and a 4-ton vacuum consumable melting furnace to melt the GH4169 alloy of the invention, with the furnace numbers marked as 1# and 2# respectively, and the comparison furnace numbers for other processes being 3#, 4#, and 5#. Among them, the VIM and ESR processes of the 3# process are the same as those of the marked furnace charges, but a weaker cooling method is used in the VAR process; the charging amount is 2100 kg; the specific steps are as follows:

[0030] Example 1

[0031] (1). Before vacuum melting, the pre-melting leak rate of the vacuum induction furnace is 35 Pa / min. The weights of the prepared materials are 1115.2 kg of Ni (nickel plate, nickel beads or nickel ingots); 409.3 kg of Cr (degassed chromium); 1.27 kg of C (high-purity graphite block); 373.9 kg of Fe (high-purity iron block), 65.3 kg of Mo (Mo beads), 105 kg of Nb (pure Nb), 18.3 kg of Ti (Ti block), 11.4 kg of Al (high-purity aluminum beans), and 12.6 kg of NiCe alloy.

[0032] (2). Add all Ni as the bottom charge. After melting clear, add Cr, C, Fe, Mo, and Nb in sequence. After melting clear again, stir for 10 - 20 min;

[0033] (3). Adjust the temperature to 1540 °C, start refining, stir for 10 min, hold for 10 min, then stir for 10 min, hold for 10 min, and the refining ends; control the temperature at 1530 °C, sample and adjust the composition to Cr (20%), C (0.04%);

[0034] (4). Adjust the temperature to 1510 °C, start adding the Ti block, stir for 10 min after melting clear. Then add Al, stir for 30 min after melting clear. Finally, add NiCe, stir for 10 min after melting clear.

[0035] (5). The pressure in the melting chamber is 10 Pa, pour, and the ingot is taken out of the furnace after cooling for 240 min;

[0036] (6) Use a grinding wheel to grind the GH4169 alloy VIM ingot, with a single-side grinding depth of 10 mm, and then use CaF:Al2O3=7:3 slag (37 slag) for ESR smelting, with the melting rate set to 150 kg / h and the slag resistance set to 12 mOhm. After smelting, the furnace is cooled for 150 minutes;

[0037] (7) The GH4169 alloy ESR ingot was polished using a lathe with a processing depth of 15 mm on one side, followed by VAR smelting with a melting rate range of 120 kg / h, a water flow rate of 1500 L / min, a cooling gas flow rate of 1200 ml / min, and furnace cooling for 120 min after smelting.

[0038] After forging, the carbide rating of each part of the final bar is 1 level (GB / T 14999.6), the purity rating is 1 level (GB / T 14999.5), and the carbide morphology is shown in Figure 1 ;

[0039] Example 2

[0040] (1) Before vacuum melting, the pre-melting leakage rate of the vacuum induction furnace is 31 Pa / min, and the weights of the prepared materials are Ni (nickel plate, nickel ball or nickel ingot) 1115.1 kg; Cr (degassed chromium) 409.3 kg; C (high-purity graphite block) 1.27 kg; Fe (high-purity iron block), 373.8 kg; Mo (Mo ball) 65.4 kg; Nb (pure Nb) 105 kg, Ti (Ti block) 18.3 kg, and Al (high-purity aluminum bean) 11.4 kg, NiCe alloy 12.6 kg.

[0041] (2) Add all Ni as a base material, and add Cr, C, Fe, Mo, and Nb in sequence after melting. After melting again, stir for 10-20 minutes;

[0042] (3) Adjust the temperature to 1540°C, start refining by stirring for 10 minutes, keep warm for 10 minutes, stir for 10 minutes, keep warm for 10 minutes, and then end refining; control the temperature to 1530°C, take samples and adjust the composition to Cr (20%) and C (0.04%);

[0043] (4) Adjust the temperature to 1510℃, start adding Ti blocks, stir for 10 minutes after melting, then add Al, stir for 30 minutes after melting, and finally add NiCe, stir for 10 minutes after melting.

[0044] (5) The pressure in the smelting chamber is 10 Pa, and pouring is carried out. After cooling for 240 minutes, the ingot is taken out of the furnace;

[0045] (6) Use a grinding wheel to grind the GH4169 alloy VIM ingot, with a single-side grinding depth of 10 mm, and then use CaF:Al2O3=7:3 slag (37 slag) for ESR smelting, with the melting rate set to 150 kg / h and the slag resistance set to 12 mOhm. After smelting, the furnace is cooled for 150 minutes;

[0046] (7) The GH4169 alloy ESR ingot was polished using a lathe with a processing depth of 15 mm on one side, followed by VAR smelting with a melting rate range of 120 kg / h, a water flow rate of 1500 L / min, a cooling gas flow rate of 1200 ml / min, and furnace cooling for 120 min after smelting.

[0047] After forging, the carbide rating of each part of the final bar is 1 level (GB / T 14999.6), the purity rating is 1 level (GB / T 14999.5), and the carbide morphology is shown in Figure 2 ;

[0048] Example 3

[0049] (1) Before vacuum melting, the pre-melting leakage rate of the vacuum induction furnace is 41 Pa / min, and the weights of the prepared materials are Ni (nickel plate, nickel ball or nickel ingot) 1110.0 kg; Cr (degassed chromium) 406.0 kg; C (high-purity graphite block) 1.23.3 kg; Fe (high-purity iron block), 373.2 kg; Mo (Mo ball) 65.0 kg; Nb (pure Nb) 105.3 kg, Ti (Ti block) 18.4 kg, and Al (high-purity aluminum bean) 11.51 kg.

[0050] (2) Add all Ni as a base material, and after melting, add Cr, Fe, Mo, and Nb to the mixture, and stir for 15 minutes after melting again;

[0051] (3) Adjust the temperature to 1545℃, stir for 10 minutes at the beginning of refining, keep warm for 10 minutes, stir for another 10 minutes, keep warm for 10 minutes and stir for 10 minutes. When refining is finished, add C.

[0052] (4) The temperature is adjusted to 1500°C and Al and Ti are added to the mixture.

[0053] (5) The pressure in the smelting chamber is 8 Pa, and pouring is carried out. After cooling for 120 minutes, the ingot is taken out of the furnace;

[0054] (6) Use a grinding wheel to grind the GH4169 alloy VIM ingot, with a single-side grinding depth of 10 mm, and then use CaF:Al2O3=7:3 slag (37 slag) for ESR smelting, with the melting rate set to 150 kg / h and the slag resistance set to 12 mOhm. After smelting, the furnace is cooled for 150 minutes;

[0055] (7) Use a lathe to finish turning the GH4169 alloy ESR ingot with a single-sided processing depth of 15 mm. Subsequently, perform VAR melting with the melting rate range set at 120 kg / h, the water flow rate set at 600 L / min, the cooling gas flow rate at 100 ml / min, and after melting, cool the furnace for 120 min.

[0056] After forging, the carbide rating of each part of the final bar is grade 2 (GB / T 14999.6), and the purity rating is grade 1.5 - 2 (GB / T 14999.5). See the carbide morphology in Figure 3 ;

[0057] Example 4

[0058] (1) Before vacuum melting, the pre-melting leak rate of the vacuum induction furnace is 23 Pa / min. Prepare the material weights as follows: Ni (nickel plate, nickel beads or nickel ingot) 1111.0 kg; Cr (degassed chromium) 406.5 kg; C (high-purity graphite block) 1.25 kg; Fe (high-purity iron block) 373.3 kg; Mo (Mo beads) 65.3 kg; Nb (pure Nb) 105.2 kg, Ti (Ti block) 18.6 kg, and Al (high-purity aluminum beans) 11.56 kg.

[0059] (2) Add all Ni as the bottom layer material. After melting is complete, add Cr, Fe, Mo, and Nb during mixing, and stir for 15 min after re-melting is complete;

[0060] (3) Adjust the temperature to 1545 °C, start refining, stir for 10 min first, hold for 10 min, stir for 10 min again, hold for 10 min, and then stir for 10 min. After refining is complete, add C.

[0061] (4) Adjust the temperature to 1500 °C, and add Al and Ti during mixing.

[0062] (5) The pressure in the melting chamber is 5 Pa, pour the molten metal, and take out the ingot after cooling for 120 min;

[0063] (6) Use a slag with CaF:Al2O3 = 7:3 (70 - 30 slag) for ESR melting, set the melting rate at 150 kg / h, and set the slag resistance at 1 mOhm. After melting, cool the furnace for 150 min;

[0064] (7) Use a lathe to finish turning the GH4169 alloy ESR ingot with a single-sided processing depth of 2 mm. Set the melting rate range at 120 kg / h, the water flow rate at 600 L / min, the cooling gas flow rate at 100 ml / min, and after melting, cool the furnace for 120 min.

[0065] After forging and forming, the carbide rating of each part of the final bar is 3-4 (GB / T 14999.6), and the purity rating is 3-4 (GB / T 14999.5). The carbide morphology is shown in Figure 4 ;

[0066] Example 5

[0067] (1) Before vacuum melting, the pre-melting leakage rate of the vacuum induction furnace is 15 Pa / min. The weights of the prepared materials are 1111.0 kg of Ni (nickel plate, nickel beads or nickel ingot); 406.5 kg of Cr (degassed chromium); 1.25 kg of C (high-purity graphite block); 373.3 kg of Fe (high-purity iron block); 65.3 kg of Mo (Mo beads); 105.2 kg of Nb (pure Nb); 18.6 kg of Ti (Ti block); and 11.56 kg of Al (high-purity aluminum pellets).

[0068] (2) Add all Ni as the bottom material. After melting is complete, mix and add Cr, Fe, Mo, and Nb, and stir for 15 min after melting again.

[0069] (3) Adjust the temperature to 1545 °C, start refining, stir for 10 min first, hold for 10 min, then stir for 10 min, hold for 10 min, and then stir for 10 min. After refining is completed, add C.

[0070] (4) Adjust the temperature to 1500 °C, mix and add Al and Ti.

[0071] (5) The pressure in the melting chamber is 5 Pa, pour, and the ingot is taken out of the furnace after cooling for 120 min.

[0072] (6) Use a slag of CaF:Al2O3 = 7:3 (70 / 30 slag) for ESR melting. Set the melting rate to 150 kg / h and the slag resistance to 1 mOhm. After melting, cool in the furnace for 150 min.

[0073] (7) Use a lathe to turn and finish the GH4169 alloy ESR ingot. The processing depth is 2 mm on one side. Set the melting rate range to 120 kg / h, the water flow rate to 600 L / min, the cooling gas flow rate to 100 ml / min, and cool in the furnace for 120 min after melting.

[0074] After forging and forming, the carbide rating of each part of the final bar is 3-4 (GB / T 14999.6), and the purity rating is 3-4 (GB / T 14999.5). The carbide morphology is shown in Figure 5 .

[0075] Although embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A triple preparation method for a high-uniform carbide GH4169 alloy, characterized in that It includes the following steps: Step 1: Knotting. Prepare a high-quality high-aluminum-based preformed crucible or a brick-shaped crucible; The alumina content is greater than 90%, the refractoriness is greater than 1770 °C, the bulk density is greater than 3.2 g / cm3, and the apparent porosity is less than 40%; Step 2: Prepare according to the component ratio: Ni, with a proportion of 51-55%; Cr with a proportion of 18-21%; C, with a proportion of 0.02-0.08%; Fe, with the remaining proportion; Mo with a proportion of 2.85-3.3%; Nb with a proportion of 4.5-5.4%. All raw materials are added into a continuous feeding hopper; Step 3: After the leak rate before vacuum induction furnace melting is lower than 250 Pa / min, add the materials prepared in Step 2 in sequence: the bottom layer material is Ni, and the other materials are added in sequence; after all are added, stir for 10 min, adjust the temperature to 1450-1550 °C for refining for 30-60 min, stir for 10 min every 10 minutes, and stir at least twice; Step 4: Prepare according to the component ratio: Ti with a proportion of 0.75-1.15%; Al with a proportion of 0.4-0.7%, and Ce with a proportion of 0.05-0.06%. After the refining is completed, adjust the melt temperature to the pouring temperature between 1450-1500 °C, and then add Ti, Al, and Ce raw materials in sequence. Stir for 10 min after adding Ti, stir for 30 min after adding Al, and stir for 10 min after adding Ce; Step 5: Use vacuum pouring. Use multi-stage baffles or filters in the pouring launder for multi-stage filtration. Cool the ingot under vacuum for more than 240 min, and then break the vacuum and take out the furnace to obtain a GH4169 alloy VIM ingot; Step 6: Use a grinding wheel to grind the GH4169 alloy VIM ingot, with the unilateral grinding depth greater than 10 mm, and then carry out ESR melting. Use a slag of CaF:Al2O3 = 7:3, and at the same time set the use of melt rate / slag resistance control during the melting process. The melt rate range is 100-200 kg / h, and the slag resistance range is greater than 10 mOhm. After melting, the furnace cooling time is greater than 120 min, and then break the vacuum to obtain a GH4169 alloy ESR ingot; Step 7: Use a lathe to turn the GH4169 alloy ESR ingot, with the processing depth greater than 15 mm, and then carry out VAR melting. The melt rate range is set to 100-150 kg / h, the water flow rate is set to 1500 L / min, and the cooling gas flow rate is 1200 ml / min. After melting, the furnace cooling time is greater than 120 min, and then break the vacuum to obtain a GH4169 alloy VAR ingot.

2. The preparation method according to claim 1, characterized in that, The Ni is nickel plate, nickel beads or nickel ingot, the Cr is degassed chromium, the C is high-purity graphite block, the Fe is high-purity iron block, the Mo is Mo beads, and the Nb is pure Nb.

3. The preparation method according to claim 1, characterized in that, In Step 2 described above, first add Ni, Cr, C, Fe, Mo, and Nb, a total of 6 main alloying elements, in proportion, without adding Ti and Al elements.

4. The preparation method according to claim 1, characterized in that, In the last step of Step 4, Ti, Al, and Ce elements are added according to the composition ratio. After the refining is completed, the melt temperature is adjusted to the casting temperature between 1450 and 1500 °C. Subsequently, Ti, Al, and Ce raw materials are added in sequence. After adding Ti, stirring is carried out for 10 min. After adding Al, stirring is carried out for 30 min. After adding Ce, stirring is carried out for 10 min.

5. The preparation method according to claim 1, wherein In Step 6, the ESR melting uses a slag with CaF:Al2O3 = 7:

3. At the same time, the melting process is controlled using the melting rate / slag resistance. The melting rate range is 100 - 200 kg / h, and the slag resistance range is greater than 10 mOhm.

6. The preparation method according to claim 5, characterized in that, The slag in Step 6 is a 70%-30% slag.

7. The preparation method according to claim 1, characterized in that, The casting pressure in Step 5 is ≤50 Pa.

8. The preparation method according to claim 1, characterized in that In Step 4, Ti is in the form of Ti blocks, Al is high-purity aluminum beans, and Ce is NiCe alloy.

Images