Low-temperature high-strength nickel-based foil strip and method for manufacturing the same

Abstract

The application discloses a low-temperature high-strength nickel-based foil strip and a preparation method thereof. The nickel-based foil strip takes a NiCr alloy as a matrix, and other elements are added to enhance the performance. According to the total mass percentage of 100%, the nickel-based foil strip comprises the following components: Cr 22%-27%, P 6%-10%, Si 2%-6%, Cu 1%-2%, Mo 1%-2%, RE 0.1%-0.5%, B 0.3%-0.5%, Zr 0.5-0.7%, and the balance is nickel. The total content of Cu and Mo is 2%-4%, and the total content of B and Zr is 1%. The nickel-based foil strip has the advantages of strong corrosion resistance, low melting point, high strength and good formability. The preparation of the nickel-based foil strip adopts a graphite tank boat with one mold and multiple outputs for casting, and multiple alloy rods are obtained through one-time casting, thereby saving a large amount of time and solving the problem of long time consumption in the existing preparation process.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of welding technology, in particular to a low-temperature high-strength nickel-based foil strip and a preparation method thereof. BACKGROUND

[0002] The three-way catalyst is one of the most important off-purification devices installed in the exhaust system of a vehicle, which can convert the harmful gases such as CO, HC and NOx discharged from the vehicle exhaust into harmless carbon dioxide, water and nitrogen through oxidation and reduction.

[0003] The stainless steel honeycomb body, as a catalyst carrier of the three-way catalyst, has a structure including a cylindrical shell and a honeycomb core, and the honeycomb core is formed by stacking and rolling metal flat strips and corrugated strips. The metal flat strips and corrugated strips, and the honeycomb core and the shell are connected together by brazing.

[0004] In the prior art, the stainless steel honeycomb carrier is usually brazed in the form of brazing filler paste applied to the welding part or brazing filler foil assembled on the welding part. The preparation process of the brazing filler paste is to melt the raw materials into an alloy melt, then to make a powder by gas atomization, and then to mix and prepare the paste with organic matter and flux for use. Due to the complex structure of the welding part of the stainless steel honeycomb carrier and the small welding gap, the process of applying the brazing filler paste is relatively cumbersome, it is difficult to apply uniformly and accurately, and it is easy to cause waste of the brazing filler paste. In addition, the binder and solvent in the brazing filler paste will volatilize when heated, and the volatilized matter will contaminate the vacuum brazing furnace, and when accumulated to a certain amount, it will reduce the vacuum degree and affect the brazing quality of the welding part of the stainless steel honeycomb carrier.

[0005] The preparation process of the brazing filler foil is as follows Figure 3 : First, the raw materials are repeatedly remelted and cast into alloy ingots under nitrogen protection, then cut into small pieces by wire cutting equipment, and then remelted and sprayed onto a high-speed rotating copper roller by a single-roll rapid cooling and strip casting machine to obtain amorphous or nanocrystalline brazing filler foil. Since the alloy ingot needs to be cut into small pieces by wire cutting equipment before being put into the quartz tube of the strip casting machine for melting, the alloy ingot is relatively hard and the cutting time is relatively long, so the process is relatively cumbersome and time-consuming and labor-intensive.

[0006] The materials suitable for brazing stainless steel are mainly nickel-based brazing filler metals. Commonly used nickel-based brazing filler metals include BNi-2, BNi-5 and BNi-7. BNi-2 belongs to the NiCrSiBFe system, and its composition is as follows: Cr content 6.0%-8.0%, Fe content 2.5%-3.5%, Si content 4.0%-5.0%, B content 2.75%-3.5%, and Ni balance; the brazing temperature is 1010°C-1177°C, and the brazing filler metal can be made into powder or foil strip. BNi-2 brazing filler metal has a low Cr content and poor corrosion resistance; has a high B content, and the brazing filler metal is easy to be made into a foil strip, but B diffuses to the base material in large quantities during brazing, and corrosion and other phenomena are prone to occur, thereby affecting the quality of the stainless steel. BNi-5 belongs to the NiCrSi system, and its composition is as follows: Cr content 18.5%-19.5%, Si content 9.75%-10.5%, and Ni balance; the brazing temperature is 1149°C-1204°C, and the brazing filler metal can be made into powder or foil strip. However, the brazing temperature of BNi-5 brazing filler metal is relatively high, close to 1200°C, and the brazing of the brazing filler metal can induce the growth of metal grains of the stainless steel base material; and the high brazing temperature leads to long heating and cooling times, low production efficiency and high comprehensive cost. BNi-7 belongs to the NiCrSi system, and its composition is as follows: Cr content 13.0%-15.0%, P content 9.7%-10.5%, and Ni balance; the brazing temperature is 927°C-1093°C, and the brazing filler metal can only be made into powder. However, the Cr content of BNi-7 brazing filler metal is not high enough, and the P content is relatively high, so the strength and corrosion resistance of the brazing filler metal are poor, and the brazing filler metal cannot be made into a foil strip. In addition, patent CN200910107824.8 discloses a NiCrPSi nickel-based brazing filler metal, and its composition is as follows: Cr content 21.5%-28.0%, P content 7.0%-9.0%, Si content 2.0%-3.5%, and Ni balance; the brazing temperature is within 1050°C, and the brazing filler metal can be made into powder or foil strip. Patent CN201711361760.5 discloses a NiCrPSi nickel-based brazing filler metal, and its composition is as follows: Cr content 27%-31%, P content 5.0%-7.0%, Si content 3.0%-5.0%, Zr content 0.5%-1%, and Ni balance; the brazing temperature is within 1090°C, and the brazing filler metal can be made into powder or foil strip. The two kinds of NiCrPSi brazing filler metals have a high Cr content and good corrosion resistance; a small amount of Zr is added to improve the amorphous forming ability; but the strength of the brazing filler metal is not enough due to the large amount of P and Si, and the foil strip prepared is brittle. SUMMARY

[0007] The application provides a low-temperature high-strength nickel-based foil strip and a preparation method thereof, and the nickel-based foil strip is prepared by taking a NiCr alloy as a base body, adding Cu, Mo and rare earth elements, and synergistically playing the roles of reducing melting, corrosion resistance, solid solution strengthening and enhancing amorphous forming ability.

[0008] The application is implemented by the following technical scheme:

[0009] The low-temperature high-strength nickel-based foil strip is prepared by taking a NiCr alloy as a base body, adding Cu, Mo and rare earth elements, and synergistically playing the roles of reducing melting, corrosion resistance, solid solution strengthening and enhancing amorphous forming ability.

[0010] Preferably, the RE is selected from La or Ce.

[0011] The nickel-based foil strip in the application takes a NiCr alloy as a base body, adds Cu, Mo and rare earth elements, and synergistically plays the roles of reducing melting, corrosion resistance, solid solution strengthening and enhancing amorphous forming ability. The Cr element in the base body can improve the corrosion resistance and oxidation resistance of the brazing filler metal, but the increase of the Cr element will cause the melting point of the brazing filler metal to increase obviously, and it is difficult to prepare the foil strip when the content of the Cr element exceeds 27%. The P and Si elements are melting reducing elements, and the P element has a stronger ability to reduce the melting point of the brazing filler metal than the Si element. Therefore, in order to obviously reduce the melting, the content of the P element should be greater than that of the Si element, and the content of the P element is controlled to be 6%-10% and the content of the Si element is controlled to be 2%-6%. However, the addition of a large amount of P and Si will form a large amount of brittle compounds in the brazing filler metal, thereby reducing the strength of the brazing joint. In order to solve the brittleness problem caused by the P and Si elements, an appropriate amount of Cu element and Mo element can be added, because Ni and Cu and Mo can be greatly mutually soluble at high temperatures, the proportion of the solid solution in the brazing filler metal can be increased, the brittle phase in the brazing filler metal can be effectively reduced, and the corrosion resistance of the brazing filler metal can be improved. However, excessive Cu and Mo will increase the melting point of the brazing filler metal, so the content of the Cu element should be controlled to be 1%-2% and the content of the Mo element should be controlled to be 1%-2%. The addition of 0.1-0.5% of the rare earth element RE (La or Ce) can refine the grains and reduce the size of the intermetallic compounds. The B and Zr elements are both elements with strong amorphous forming ability, and the content of the B element should be less than 1% in order to reduce the diffusion to the stainless steel. In addition, the addition of 0.5%-1% of the Zr element is beneficial to the preparation of the amorphous foil strip.

[0012] The application also protects the preparation method of the above low-temperature high-strength nickel-based foil strip, comprising the following steps:

[0013] 1) batching and smelting: after the raw materials are weighed and prepared according to the mass percentage, they are put into a vacuum medium-frequency smelting furnace, vacuum is first extracted, and then argon protection is filled, medium frequency is turned on for alloying smelting, after slag removal and refining, the alloy ingot is cast into a crucible and cooled to form an alloy ingot; the alloy ingot is repeatedly remelted 3-5 times according to the above steps, and then cast into a graphite tank boat provided with more than three grooves, and cooled to obtain more than three alloy rods with the same specifications;

[0014] 2) strip casting: the alloy rod obtained in step 1) is put into a quartz tube, vertically placed in an induction coil and fixed on a fixed frame of a single-roll rapid cooling strip casting machine, vacuum is extracted and argon protection is filled, the alloy melt is remelted by induction heating and sprayed to a rapidly rotating copper roller under pressure, and the foil strip is prepared after cooling.

[0015] Preferably, in step 1), the purity of Ni, Cr, Si, Cu, RE elements, P, B and Zr elements is more than 99.9%, and the elements are added in the form of Ni-P, Ni-B and Ni-Zr intermediate alloy.

[0016] Preferably, in step 1), the raw materials are put into a vacuum medium-frequency smelting furnace, a mechanical pump is first opened to extract to below 700 Pa, a Roots pump is then opened to extract to 10 -2 Pa, and then argon protection is filled.

[0017] Preferably, in step 1), the graphite tank boat is compounded with carbon and ceramic at high temperature by PVD process to form a stable carbide crystal structure, the structure of the graphite tank boat is one mold with multiple outputs, the graphite tank boat is composed of a bottom plate and side walls, a plurality of grooves are formed on the upper surface of the bottom plate, the grooves have a trapezoidal structure with a wide top and a narrow bottom, the grooves are arranged in sequence according to the connection order of the groove top surface, the first inclined surface, the groove bottom surface and the second inclined surface, the two sides of the end groove are the side walls, the two side walls have the same specifications, the length of the inclined surface near the two ends in the grooves near the two ends is greater than the length of the inclined surface near the middle groove, the lengths of the two inclined surfaces of the middle groove are equal, the included angle between the two inclined surfaces of the groove is 30°, the number of the middle grooves is not less than 1, the top surface of the groove near the two ends is higher than the top surface of the middle groove, and the top surface of the middle groove is coated with an anti-sticking reinforcing layer.

[0018] The process parameters of step 2) are as follows: the diameter of beryllium copper is 400 mm, the copper roller rotates at a speed of 500-2000 rpm, the cooling speed is greater than 10 6 / sec; the width of the nozzle is 10-20 mm, the caliber is 1.5 mm; the distance between the nozzle and the surface of the copper roller is 0.2-0.4 mm; the argon injection pressure is 30-50 KPa; and the smelting temperature is 1300-1400℃.

[0019] Preferably, the prepared nickel-based foil strip has a width of 10-20 mm and a thickness of 35-45 μm.

[0020] The beneficial effects of the present application are as follows:

[0021] 1) The nickel-based foil strip of the present application takes NiCr alloy as the matrix, by adding a higher Cr element, the nickel-based foil strip has higher corrosion resistance; by adding a large amount of melting element P and Si, the melting point of the filler metal is reduced to within 1100℃, avoiding the growth of stainless steel grains caused by high brazing temperature; by adding Cu, Mo and rare earth elements, they play a synergistic role, increase the proportion of solid solution in the filler metal, effectively reduce the brittle phase in the filler metal, improve the corrosion resistance of the filler metal, and refine the grain of the brittle phase, so as to realize the goal of reducing the melting point of the filler metal and improving the corrosion resistance of the filler metal, and the strength of the filler metal will not decrease; by reducing the content of B element in the nickel-based filler metal, the diffusion of B element to stainless steel is reduced; by adding Zr element, the amorphous forming ability of the nickel-based foil strip is further strengthened.

[0022] 2) The method for preparing the nickel-based foil strip of the present application can cast multiple short rods at one time by pouring the molten liquid onto the graphite tank boat, which can be repeatedly used, and saves a lot of time compared with cutting into small pieces by wire cutting; the graphite tank boat used adopts PVD process to composite carbon and ceramic at high temperature to form stable carbide crystal structure, which has high strength, excellent high temperature oxidation resistance and corrosion resistance, completely solves the problem of difficult demolding caused by easy adhesion of alloy bar to graphite boat, and improves the demolding efficiency and quality of alloy bar. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 The design drawing of the graphite tank boat used for the embodiments of the present application is shown in the figure, wherein the left is a perspective structure diagram, and the right is a cross-sectional view, 1 is a bottom plate, 2 is a side wall, 3 is a first groove top surface, 4 is a first groove first inclined surface, 5 is a first groove bottom surface, 6 is a second groove top surface, 7 is a first groove second inclined surface, 8 is a second groove first inclined surface, 9 is a third groove second inclined surface, 10 is a second groove second inclined surface, and 11 is a third groove first inclined surface.

[0024] Figure 2 The preparation flow chart of the nickel-based foil strip of the present application is shown in the figure.

[0025] Figure 3 The preparation flow chart of the filler metal foil strip of the prior art is shown in the figure. DETAILED DESCRIPTION

[0026] Those skilled in the art will appreciate that the technology disclosed in the following examples represents techniques found by the inventors to function well in the practice of the application. However, many changes can be made to the disclosed specific embodiments and still obtain the same or similar results without departing from the spirit and scope of the application.

[0027] The graphite groove boat design used in the embodiments of the present application adopts a one-mold multi-outlet structure, as shown in Figure 1 The bottom plate 1 is a plane, and the upper surface of the bottom plate 1 is provided with three grooves. The grooves are trapezoidal structures with the upper width being larger than the lower width. The grooves are continuously arranged in the following order: the top surface of the first groove 3, the first inclined surface of the first groove 4, the bottom surface of the first groove 5, and the second inclined surface of the first groove 7. The two sides of the end groove are the side walls, and the two side walls have the same specifications. The length of the inclined surface near the two ends in the groove near the two ends (for example, the length of the first inclined surface 4 of the first groove is greater than the length of the second inclined surface 7 near the middle groove). The lengths of the two inclined surfaces of the middle groove are equal (for example, the lengths of the first inclined surface 8 of the second groove and the second inclined surface 10 of the second groove are equal). The included angle between the two inclined surfaces of the groove is 30°. The top surface of the groove near the two ends, for example, the top surface 3 of the first groove, is higher than the top surface of the middle groove, for example, the top surface 6 of the second groove. In order to ensure that each graphite groove can be filled with molten liquid and prevent the molten liquid from flowing out, the top surface 6 of the middle groove is coated with an anti-sticking reinforcing layer. The position is connected together during casting, and a coating is added for good demolding.

[0028] The manufacturing method of the graphite groove boat is to composite carbon and ceramic at high temperature by PVD process to form a stable carbide crystal structure, which has excellent high-temperature oxidation resistance and corrosion resistance, completely solves the problem of easy adhesion of alloy bars to graphite boat grooves, resulting in difficult demolding, and improves the demolding efficiency and quality of the alloy bars. After carbon and ceramic are compounded, the strength of the graphite groove boat is higher, greatly improving the service life of the graphite groove boat. When remelting and manufacturing alloy bars of nickel-based alloy, the graphite groove boat is placed under the furnace mouth of the vacuum melting furnace and fixed. After the alloy is heated and melted, the alloy melt is poured into the graphite boat groove from the furnace mouth under the protection of argon atmosphere. When the alloy melt flows into all the grooves and is at the same level, the casting is completed. A plurality of alloy bars with consistent specifications are formed after solidification, greatly improving the production efficiency of nickel-based alloy bars.

[0029] Example 1

[0030] A low-temperature high-strength nickel-based foil strip, the raw materials include the following components in total mass percentage of 100%: Cr 22%, P 7%, Si 5%, Cu 2%, Mo 2%, La 0.5%, B 0.5%, Zr 0.5%, and the balance is nickel.

[0031] The preparation method steps are as follows:

[0032] (1)Batching: Selecting Ni, Cr, Si, Cu, La elements with purity of 99.9% or above. P, B, Zr elements in the solder are added in the form of Ni-P, Ni-B, Ni-Zr intermediate alloy. Weighing according to the above mass percentage.

[0033] (2) Melting: Put the prepared raw materials into a vacuum medium frequency melting furnace, open the mechanical pump to below 700 Pa, then open the Roots pump to 10 Pa, then fill in argon protection, open the medium frequency to alloying melting, after deslagging and refining, pour into the crucible to cool into alloy ingot. The alloy ingot is repeatedly remelted 3 times according to the above steps and poured into the graphite groove boat with three or more grooves as shown in the figure to cool to obtain three or more alloy rods with consistent specifications. -2 Figure 1

[0034] (3) Spinning: Put the alloy rod into a quartz tube, vertically into the induction coil and fixed on the fixed frame of the single-roll rapid cooling spinning machine, vacuumize and fill in argon protection, remelt by induction heating and pressurize the melted alloy melt to spray onto the rapidly rotating copper roller, and cool to form a foil. The required process parameters are: the diameter of beryllium copper is 400 mm, the copper roller speed is 2000 rpm, the cooling speed is greater than 10 6 / sec; the width of the nozzle is 10 mm, the caliber is 1.5 mm; the distance between the nozzle and the surface of the copper roller is 0.4 mm; the argon spraying pressure is 50 KPa; the melting temperature is 1300℃. After preparation, a nickel-based foil with a width of 10 mm and a thickness of 45 μm is obtained.

[0035] Comparative Example 1

[0036] Reference Example 1, except that the solder composition does not contain Cu element.

[0037] A low-temperature high-strength nickel-based foil, the solder composition is Cr 22%, P 7%, Si 5%, Mo 2%, La 0.5%, B 0.5%, Zr 0.5%, and the balance is nickel.

[0038] The other steps are the same as Example 1.

[0039] Comparative Example 2

[0040] Reference Example 1, except that the solder composition does not contain Mo element and La element.

[0041] A low-temperature high-strength nickel-based foil, the solder composition is Cr 22%, P 7%, Si 5%, Cu 2%, B 0.5%, Zr 0.5%, and the balance is nickel.

[0042] The other steps are the same as Example 1. ​​

[0043] Comparative Example 3

[0044] Referring to Example 1, the difference is that in the process of nickel-based foil strip production, the raw materials are melted and cast into alloy ingots, which are then cut into small pieces and placed into a strip spinning machine for preparation.

[0045] (2) Melting: The prepared raw materials are placed in a vacuum medium-frequency melting furnace. The mechanical pump is turned on sequentially to pump the material to below 700 Pa, and then the Roots pump is turned on to pump the material to below 10 Pa. -2 Pa, then argon gas is introduced for protection, and medium frequency is turned on for alloying and melting. After slag removal and refining, it is cast into a crucible and cooled into an alloy ingot. The alloy ingot is then cut into small pieces.

[0046] The other steps are the same as in Example 1.

[0047] Example 2

[0048] A low-temperature, high-strength nickel-based foil strip, with a solder composition of Cr 23%, P 6%, Si 5%, Cu 1.5%, Mo 1.5%, and La.

[0049] 0.4% B, 0.4% Zr, balance nickel.

[0050] The preparation method steps are as follows:

[0051] (1) Ingredients: Select Ni, Cr, Si, Cu, and La elements with a purity of 99.9% or higher. P, B, Zr, and other elements in the solder are added in the form of Ni-P, Ni-B, and Ni-Zr master alloys. Weigh according to the above mass percentage ratio.

[0052] (2) Melting: The prepared raw materials are placed in a vacuum medium-frequency melting furnace. The mechanical pump is turned on sequentially to pump the material to below 700 Pa, and then the Roots pump is turned on to pump the material to below 10 Pa. -2 Pa, then argon gas is introduced for protection, and medium-frequency induction is turned on for alloying melting. After slag removal and refining, it is cast into a crucible and cooled into an alloy ingot. The alloy ingot is then remelted three times using the above steps before being cast into a... Figure 1 The graphite boat shown has three or more grooves, from which three or more alloy bars of the same specifications are obtained by cooling.

[0053] (3) Strip spinning: The alloy rod is placed in a quartz tube, vertically placed in an induction coil, and fixed on the frame of a single-roller rapid cooling strip spinning machine. A vacuum is drawn and argon gas is introduced for protection. The alloy is remelted by induction heating, and the molten alloy is pressurized and sprayed onto a rapidly rotating copper roller. After cooling, it is formed into a foil strip. The required process parameters are: beryllium copper roller diameter 400mm, copper roller speed 1000rpm, cooling rate greater than 10... 6The width of the nozzle is 15 mm, the caliber is 1.5 mm, the distance between the nozzle and the surface of the copper roller is 0.3 mm, the argon spraying pressure is 40 KPa, and the smelting temperature is 1400℃. After preparation, a nickel-based brazing filler metal foil strip with a width of 15 mm and a thickness of 40 μm is obtained.

[0054] Example 3

[0055] A low-temperature high-strength nickel-based foil strip, the brazing filler metal composition is Cr 27%, P 6%, Si 6%, Cu 2%, Mo 2%, La

[0056] 0.5%, B 0.3%, Zr 0.7%, La 0.2%, and the balance is nickel.

[0057] The preparation method steps are as follows:

[0058] (1) batching: the purity of the selected Ni, Cr, Si, Cu, La elements is more than 99.9%. The P, B, Zr and other elements in the brazing filler metal are added in the form of Ni-P, Ni-B, Ni-Zr intermediate alloy. Weigh according to the above mass percentage.

[0059] (2) smelting: put the prepared raw materials into a vacuum medium-frequency smelting furnace, open the mechanical pump to below 700 Pa, then open the Roots pump to 10 -2 Pa, then fill in argon protection, open the medium frequency to alloy smelting, after deslagging and refining, pour into a crucible to cool into an alloy ingot. The alloy ingot is repeatedly remelted 3 times according to the above steps and poured into Figure 1 a graphite tank boat provided with three or more grooves, and three or more alloy rods with the same specifications are obtained by cooling.

[0060] (3) strip casting: put the alloy rod into a quartz tube, vertically into the induction coil and fix it on the fixing frame of the single-roller rapid cooling strip casting machine, vacuumize and fill in argon protection, spray the molten alloy melt to the rapidly rotating copper roller through induction heating, and cool to form a foil strip. The required process parameters are: the diameter of the beryllium copper roller is 400 mm, the copper roller rotating speed is 2000 rpm, the cooling speed is greater than 10 6 / sec; the width of the nozzle is 20 mm, the caliber is 1.5 mm; the distance between the nozzle and the surface of the copper roller is 0.2 mm; the argon spraying pressure is 30 KPa; the smelting temperature is 1300℃. After preparation, a nickel-based brazing filler metal foil strip with a width of 20 mm and a thickness of 35 μm is obtained.

[0061] The nickel-based brazing filler metal of examples 1-3, comparative examples 1-2 and commercial nickel-based brazing filler metals BNi-2, BNi-5, BNi-7 and NiCrPSi (source CN200910107824.8), NiCrPSiZr (source CN201711361760.5) were tested for performance, and the results are shown in Table 1. As can be seen from Table 1, examples 1 and comparative examples 1 and 2, the addition of Cu, Mo and rare earth elements makes them play a synergistic effect, increases the proportion of solid solution in the brazing filler metal, effectively reduces the brittle phase in the brazing filler metal, and improves the corrosion resistance of the brazing filler metal.

[0062] Table 1 Comparison of performance test results of nickel-based brazing filler metal

[0063]

[0064]

[0065] Table 2 Comparison of performance and preparation time of nickel-based brazing filler metal

[0066]

[0067] The nickel-based brazing filler metal prepared in example 1 and comparative example 3 was tested for performance, and the preparation time was counted. The results are shown in Table 2.

Claims

1. A low-temperature, high-strength nickel-based foil strip, characterized in that, The raw materials, based on a total mass percentage of 100%, consist of the following components: Cr 22%-27%, P 6%-10%, Si 2%-6%, Cu 1%-2%, Mo 1%-2%, RE 0.1%-0.5%, B 0.3%-0.5%, Zr 0.5%-0.7%, with the balance being nickel; the total content of Cu and Mo is 2%-4%, and the total content of B and Zr is 1%.

2. The low-temperature high-strength nickel-based foil strip according to claim 1, characterized in that, RE is selected from La or Ce.

3. The method for preparing low-temperature high-strength nickel-based foil strip according to claim 1, characterized in that, Includes the following steps: 1) Batching and smelting: After weighing the raw materials according to the mass percentage, they are placed in a vacuum medium-frequency melting furnace. First, a vacuum is drawn and then argon gas is introduced for protection. The medium frequency is turned on for alloying and smelting. After slag removal and refining, the alloy is cast into a crucible and cooled into an alloy ingot. The alloy ingot is then remelted repeatedly according to the above steps 3-5 times. After casting, it is cast into a graphite groove boat with three or more grooves and cooled to obtain three or more alloy bars of the same specifications. 2) Strip spinning: The alloy rod obtained in step 1) is placed in a quartz tube, vertically placed in an induction coil and fixed on the fixed frame of a single-roller rapid cooling strip spinning machine. Vacuum is drawn and argon gas is filled for protection. The alloy is remelted by induction heating and the molten alloy liquid is pressurized and sprayed onto a rapidly rotating copper roller. After cooling, it is made into foil strip.

4. The method according to claim 3, characterized in that, In step 1), the raw material preparation process selects Ni, Cr, Si, Cu, RE elements with a purity of 99.9% or higher, and P, B, and Zr elements are added in the form of Ni-P, Ni-B, and Ni-Zr master alloys.

5. The method according to claim 3, characterized in that, In step 1), the raw material is placed in a vacuum medium-frequency melting furnace. First, the mechanical pump is turned on to pump the material to below 700 Pa, and then the Roots pump is turned on to pump the material to below 10 Pa. -2 Pa, then fill with argon gas for protection.

6. The method according to claim 3, characterized in that, In step 1), the graphite trough boat uses PVD technology to composite carbon and ceramic at high temperature to form a stable carbide crystal structure. The graphite trough boat has a multi-mold structure and consists of a bottom plate and side walls. Several grooves are formed on the upper surface of the bottom plate. The grooves are trapezoidal structures that are wider at the top and narrower at the bottom. The grooves are arranged continuously in the order of groove top surface, first inclined surface, groove bottom surface, and second inclined surface. The two sides of the end grooves are the side walls. The two side walls have the same specifications. The length of the inclined surface near the two ends of the grooves is greater than the length of the inclined surface near the middle groove. The two inclined surfaces of the middle grooves are of equal length. There is no less than one middle groove. The angle between the extension lines of the two inclined surfaces of the grooves is 30°. The top surface of the grooves near the two ends is higher than the top surface of the middle groove. The top surface of the middle groove is coated with an anti-sticking reinforcing layer.

7. The method according to claim 3, characterized in that, Step 2) The process parameters are: beryllium copper diameter is 400mm, copper roller speed is 500-2000rpm, and cooling rate is greater than 10. 6 / sec; nozzle width is 10-20mm, orifice diameter is 1.5mm; nozzle-to-copper roller surface distance is 0.2-0.4mm; argon injection pressure is 30-50KPa; smelting temperature is 1300-1400℃.

8. The method according to claim 3, characterized in that, The prepared nickel-based foil strips have a width of 10-20 mm and a thickness of 35-45 μm.

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