Nickel-based rolled composite plate and preparation method thereof

Abstract

The invention discloses a nickel-based rolled composite plate and a preparation method thereof, and relates to the technical field of alloys. When the nickel-based rolled composite plate is prepared, pure nickel blocks and ytterbium powder are melted and mixed, and a rare earth-nickel intermediate alloy is prepared through a high-energy ultrasonic method; nickel powder, aluminum powder and germanium powder serve as raw materials, and the aluminum-germanium modified nickel alloy is prepared through ball milling, pressing and sintering. The rare earth-nickel intermediate alloy and the aluminum-germanium modified nickel alloy are melted and mixed, and the modified nickel alloy is prepared through a high-energy ultrasonic method; a pipeline steel plate and modified nickel alloy are combined through a welding technology, and the nickel-based rolled composite plate is prepared through a vacuum rolling composite method. The nickel-based rolled composite plate prepared by the invention has excellent mechanical properties and corrosion resistance.

Description

Technical Field

[0001] This invention relates to the field of alloy technology, specifically to a nickel-based rolled composite plate and its preparation method. Background Technology

[0002] In today's era, due to the continuous development of the automotive, shipbuilding, and industrial sectors, the demand for materials is showing a diversified trend and a higher requirement for material performance. However, a single material cannot simultaneously possess all the excellent performance characteristics. Therefore, to meet this demand, materials will tend towards a composite trend in the future, allowing materials to simultaneously possess different excellent properties to meet needs; among them, rolled composite plates are an important type of composite material. Nickel-based rolled composite plates are bimetallic composite materials with nickel-based alloys as the cladding and carbon steel or low-alloy steel as the base layer, and are widely used in high-end equipment manufacturing. Nickel-based rolled composite plates are mainly used under high temperature, high pressure, and corrosive environments, but they suffer from insufficient strength and susceptibility to corrosion. Therefore, it is necessary to improve existing technologies to enhance the strength and corrosion resistance of nickel-based rolled composite plates. Summary of the Invention

[0003] The purpose of this invention is to provide a nickel-based rolled composite plate and its preparation method to solve the problems existing in the prior art.

[0004] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0005] A nickel-based rolled composite plate, wherein the nickel-based rolled composite plate is obtained by vacuum rolling composite method of modified nickel alloy and pipeline steel plate;

[0006] The preparation method of the nickel-based rolled composite plate includes the following preparation steps:

[0007] S1. Surface-treat the 22mm thick modified nickel alloy and the 180mm thick pipeline steel plate. Combine the pipeline steel plate and the modified nickel alloy using a symmetrical assembly method, placing the pipeline steel plate on the outermost side to complete the assembly.

[0008] S2. Weld and seal the assembled modified nickel alloy and pipeline steel plates, and then perform vacuum treatment. The vacuum degree of the vacuum treatment shall not be less than 10. -2 Pa, to obtain a composite blank;

[0009] S3. Heat the composite billet to 1200~1300℃ at a heating rate of 10℃ / min, hold it at that temperature for 8~10h and then start rough rolling. Immediately after rough rolling, heat the composite billet to 800~1500℃ and start finish rolling. After finish rolling, cool it down.

[0010] S4. After the composite billet has been cooled by precision rolling, it is first subjected to hot straightening, and then placed at a temperature of 500-1100℃ for heat treatment. After the heat treatment is completed, it is cut, separated into plates, leveled, polished and inspected, and then printed, packaged and shipped to obtain nickel-based rolled composite plates.

[0011] As an optimization, the modified nickel alloy is prepared by melting and mixing a rare earth-nickel master alloy and an aluminum-germanium modified nickel alloy, and then using a high-energy ultrasonic method; wherein, the rare earth-nickel master alloy is prepared by melting and mixing pure nickel blocks and ytterbium powder, and then using a high-energy ultrasonic method; the aluminum-germanium modified nickel alloy is prepared by using nickel powder, aluminum powder, and germanium powder as raw materials, and then by ball milling, pressing, and sintering.

[0012] As an optimization, the modified nickel alloy is prepared using the following steps:

[0013] (1) Preheat the graphite crucible to 500~520℃, put in pure nickel blocks, heat to 1400~1500℃, stir at 200~300r / min for 10~12min, add ytterbium powder at 0.06~0.08 times the mass of pure nickel blocks, continue stirring for 20~30min, preheat the ultrasonic concentrator of the ultrasonic device to 300~400℃, place the ultrasonic concentrator in the melt for ultrasonic treatment, refine and remove slag from the melt, pour it into a metal mold, cool to room temperature, and obtain rare earth-nickel master alloy;

[0014] (2) Mix the powder and polyethylene glycol at a mass ratio of 1:(0.006~0.008) evenly, place them in a mold, put the mold on a press, apply a pressure of 550~560MPa, hold for 2~3min to obtain a blank; place the blank in a sintering furnace, heat from room temperature to 350~360℃ at a heating rate of 10℃ / min, hold for 2~3h, heat to 1250~1260℃ at a heating rate of 5℃ / min, hold for 2~3h, cool to room temperature to obtain an aluminum-germanium modified nickel alloy;

[0015] (3) Preheat the graphite crucible to 380~420℃ in a pit-type resistance furnace. Place the rare earth-nickel master alloy and aluminum-germanium modified nickel alloy into the crucible at a mass ratio of 1:(2~2.2) and heat it to 1400~1500℃. Preheat the ultrasonic concentrator of the ultrasonic device to 300~400℃. Place the ultrasonic concentrator in the melt for ultrasonic treatment. Refine and remove slag from the melt. Pour it into a metal mold and cool it to room temperature to obtain the modified nickel alloy.

[0016] As an optimization, the process parameters for the ultrasonic treatment in step (1) are as follows: the ultrasonic concentrator is set to be located 16-20 cm below the surface of the melt, the ultrasonic output frequency is 1.4-1.6 kHz, the ultrasonic output power is 600-700 W, and the ultrasonic time is 10-12 min; the ytterbium powder has a mesh size of 400 mesh.

[0017] As an optimization, the preparation method of the mixed powder in step (2) is as follows: mix nickel powder, aluminum powder and germanium powder evenly, place them in a ball mill, and ball mill under argon protection. Set the ball-to-material ratio to (9~10):1, the ball milling speed to 140~160 r / min, and the ball milling time to 7~9 h to obtain the mixed powder.

[0018] As an optimization, the mass ratio of nickel powder, aluminum powder, and germanium powder is 1:(0.06~0.08):(0.04~0.06).

[0019] As an optimization, the nickel powder has a mesh size of 300, the aluminum powder has a mesh size of 400, and the germanium powder has a mesh size of 600.

[0020] As an optimization, the polyethylene glycol in step (2) is of type PEG2000.

[0021] As an optimization, the process parameters for ultrasonic treatment in step (3) are as follows: the ultrasonic concentrator is set to be located 16-20 cm below the surface of the melt, the ultrasonic output frequency is 1.4-1.6 kHz, the ultrasonic output power is 600-700 W, and the ultrasonic time is 14-16 min.

[0022] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0023] In preparing nickel-based rolled composite plates, this invention involves melting and mixing pure nickel blocks and ytterbium powder, and then using a high-energy ultrasonic method to obtain a rare earth-nickel master alloy; using nickel powder, aluminum powder, and germanium powder as raw materials, an aluminum-germanium modified nickel alloy is obtained through ball milling, pressing, and sintering; the rare earth-nickel master alloy and the aluminum-germanium modified nickel alloy are melted and mixed, and a modified nickel alloy is obtained through a high-energy ultrasonic method; and pipeline steel plates and the modified nickel alloy are combined using welding technology, and a nickel-based rolled composite plate is obtained through a vacuum rolling composite method.

[0024] First, pure nickel blocks and ytterbium powder are melted and mixed, and a rare earth-nickel master alloy is prepared by high-energy ultrasonic method. The addition of ytterbium powder can refine the grains. The ytterbium powder is uniformly dispersed in the nickel-based alloy by high-energy ultrasonic method, which helps to hinder dislocation movement and grain boundary slip, and at the same time reduces the atomic diffusion rate in the matrix, thereby achieving a dispersion strengthening effect on the nickel-based alloy, inhibiting grain boundary corrosion, and giving the nickel-based rolled composite plate excellent mechanical properties and corrosion resistance.

[0025] Secondly, using nickel powder, aluminum powder, and germanium powder as raw materials, an aluminum-germanium modified nickel alloy was prepared by ball milling, pressing, and sintering. The addition of Ge element reduced the migration rate of Ni element from the matrix to the surface. Al element has a smaller atomic radius and a relatively faster migration rate compared to other metal elements, making it easier to contact oxygen in the air, thereby forming a complete aluminum oxide film on the alloy surface, which hinders further oxidation by oxygen and improves the corrosion resistance of the alloy. Detailed Implementation

[0026] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0027] The polyethylene glycol used in the following examples and comparative examples is PEG2000;

[0028] The ytterbium powder used has a mesh size of 400, the nickel powder has a mesh size of 300, the aluminum powder has a mesh size of 400, and the germanium powder has a mesh size of 600.

[0029] Example 1:

[0030] A method for preparing a nickel-based rolled composite plate, the method comprising the following steps:

[0031] (1) Preheat the graphite crucible to 500°C, put in pure nickel blocks, heat to 1400°C, stir at 200r / min for 12min, add ytterbium powder at 0.06 times the mass of pure nickel blocks, continue stirring for 30min, preheat the ultrasonic concentrator of the ultrasonic device to 300°C, place the ultrasonic concentrator in the melt for ultrasonic treatment, set the ultrasonic concentrator to 16cm below the melt surface, the ultrasonic output frequency is 1.4KHz, the ultrasonic output power is 600W, the ultrasonic time is 12min, refine and remove slag from the melt, pour it into a metal mold, cool to room temperature, and obtain rare earth-nickel master alloy;

[0032] (2) Nickel powder, aluminum powder and germanium powder are mixed evenly in a mass ratio of 1:0.06:0.04 and placed in a ball mill. The ball milling is carried out under argon protection. The ball-to-material ratio is set to 9:1, the ball milling speed is 140 r / min, and the ball milling time is 9 h to obtain a mixed powder. The mixed powder and polyethylene glycol are mixed evenly in a mass ratio of 1:0.006 and placed in a mold. The mold is placed on a press and a pressure of 550 MPa is applied. The pressure holding time is 3 min to obtain a blank. The blank is placed in a sintering furnace and heated from room temperature to 350°C at a heating rate of 10°C / min. The temperature is held for 3 h. The temperature is then raised to 1250°C at a heating rate of 5°C / min. The temperature is held for 3 h. The blank is cooled to room temperature to obtain an aluminum-germanium modified nickel alloy.

[0033] (3) Preheat the graphite crucible to 380°C in a pit-type resistance furnace. Place the rare earth-nickel master alloy and aluminum-germanium modified nickel alloy into the crucible at a mass ratio of 1:2 and heat to 1400°C. Preheat the ultrasonic concentrator of the ultrasonic device to 300°C. Place the ultrasonic concentrator in the melt for ultrasonic treatment. Set the ultrasonic concentrator to 16cm below the melt surface. The ultrasonic output frequency is 1.4KHz, the ultrasonic output power is 600W, and the ultrasonic time is 16min. Refine and remove slag from the melt. Pour the melt into a metal mold and cool to room temperature to obtain the modified nickel alloy. Perform surface treatment on 10mm thick modified nickel alloy and 18mm thick pipeline steel plate. Combine the pipeline steel plate and modified nickel alloy using a symmetrical assembly method. Place the pipeline steel plate on the outermost side to complete the assembly. Weld the assembled modified nickel alloy and pipeline steel plate to seal the edges and perform vacuum treatment. The vacuum degree of the vacuum treatment is not less than 10. -2 Pa was used to prepare a composite billet. The composite billet was heated to 1200℃ at a heating rate of 10℃ / min and held for 8 hours before rough rolling. After rough rolling, the temperature of the composite billet reached 880℃ before finish rolling. The finished product specifications were 3+24.5mm. After finish rolling, the billet was cooled. The composite billet after finish rolling and cooling was first hot straightened and then placed at 500℃ for heat treatment. After heat treatment, it was cut, separated into plates, leveled, polished, and inspected before being printed, packaged, and shipped to obtain a nickel-based rolled composite plate.

[0034] Example 2:

[0035] A method for preparing a nickel-based rolled composite plate, the method comprising the following steps:

[0036] (1) Preheat the graphite crucible to 510°C, put in pure nickel blocks, heat to 1450°C, stir at 250r / min for 11min, add ytterbium powder at 0.07 times the mass of pure nickel blocks, continue stirring for 25min, preheat the ultrasonic concentrator of the ultrasonic device to 350°C, place the ultrasonic concentrator in the melt for ultrasonic treatment, set the ultrasonic concentrator to 17cm below the melt surface, the ultrasonic output frequency is 1.5KHz, the ultrasonic output power is 650W, the ultrasonic time is 11min, refine and remove slag from the melt, pour it into a metal mold, cool to room temperature, and obtain rare earth-nickel master alloy;

[0037] (2) Nickel powder, aluminum powder and germanium powder are mixed evenly in a mass ratio of 1:0.07:0.05 and placed in a ball mill. The ball milling is carried out under argon protection. The ball-to-material ratio is set to 9.5:1, the ball milling speed is 150 r / min, and the ball milling time is 8 h to obtain a mixed powder. The mixed powder and polyethylene glycol are mixed evenly in a mass ratio of 1:0.007 and placed in a mold. The mold is placed on a press and a pressure of 555 MPa is applied. The holding time is 2.5 min to obtain a blank. The blank is placed in a sintering furnace and heated from room temperature to 355℃ at a heating rate of 10℃ / min and held for 2.5 h. Then, the temperature is raised to 1255℃ at a heating rate of 5℃ / min and held for 2.5 h. The blank is cooled to room temperature to obtain an aluminum-germanium modified nickel alloy.

[0038] (3) Preheat the graphite crucible to 400°C in a pit-type resistance furnace. Place the rare earth-nickel master alloy and aluminum-germanium modified nickel alloy in the crucible at a mass ratio of 1:2.1 and heat to 1450°C. Preheat the ultrasonic concentrator of the ultrasonic device to 350°C. Place the ultrasonic concentrator in the melt for ultrasonic treatment. Set the ultrasonic concentrator to 18cm below the melt surface. The ultrasonic output frequency is 1.5KHz, the ultrasonic output power is 650W, and the ultrasonic time is 15min. Refine and remove slag from the melt. Pour it into a metal mold and cool it to room temperature to obtain the modified nickel alloy. Perform surface treatment on 10mm thick modified nickel alloy and 18mm thick pipeline steel plate. Combine the pipeline steel plate and modified nickel alloy using a symmetrical assembly method. Place the pipeline steel plate on the outermost side to complete the assembly. Weld the assembled modified nickel alloy and pipeline steel plate to seal the edges and perform vacuum treatment. The vacuum degree of the vacuum treatment is not less than 10. -2Pa was used to prepare a composite billet. The composite billet was heated to 1180℃ at a heating rate of 10℃ / min and held at that temperature for 90h before rough rolling. After rough rolling, the temperature of the composite billet reached 850℃ before finish rolling. The finished product specifications were 3+24.5mm. After finish rolling, the billet was cooled. The composite billet after finish rolling and cooling was first hot straightened and then placed at 600℃ for heat treatment. After heat treatment, it was cut, separated into plates, leveled, polished, and inspected before being printed, packaged, and shipped to the factory to obtain a nickel-based rolled composite plate.

[0039] Example 3:

[0040] A method for preparing a nickel-based rolled composite plate, the method comprising the following steps:

[0041] (1) Preheat the graphite crucible to 510°C, put in pure nickel blocks, heat to 1500°C, stir at 300r / min for 10min, add ytterbium powder at 0.08 times the mass of pure nickel blocks, continue stirring for 20min, preheat the ultrasonic concentrator of the ultrasonic device to 400°C, place the ultrasonic concentrator in the melt for ultrasonic treatment, set the ultrasonic concentrator to 20cm below the melt surface, the ultrasonic output frequency is 1.6KHz, the ultrasonic output power is 700W, the ultrasonic time is 10min, the melt is refined and slag is removed, and it is poured in a metal mold and cooled to room temperature to obtain rare earth-nickel master alloy;

[0042] (2) Nickel powder, aluminum powder and germanium powder are mixed evenly in a mass ratio of 1:0.08:0.06 and placed in a ball mill. The ball milling is carried out under argon protection. The ball-to-material ratio is set to 10:1, the ball milling speed is 160 r / min, and the ball milling time is 7 h to obtain mixed powder. The mixed powder and polyethylene glycol are mixed evenly in a mass ratio of 1:0.008 and placed in a mold. The mold is placed on a press and a pressure of 560 MPa is applied. The pressure holding time is 2 min to obtain a blank. The blank is placed in a sintering furnace and heated from room temperature to 360°C at a heating rate of 10°C / min and held for 2 h. Then, the temperature is raised to 1260°C at a heating rate of 5°C / min and held for 2 h. The blank is cooled to room temperature to obtain aluminum-germanium modified nickel alloy.

[0043] (3) Preheat the graphite crucible to 420°C in a pit-type resistance furnace. Place the rare earth-nickel master alloy and aluminum-germanium modified nickel alloy in the crucible at a mass ratio of 1:2.2 and heat to 1500°C. Preheat the ultrasonic concentrator of the ultrasonic device to 400°C. Place the ultrasonic concentrator in the melt for ultrasonic treatment. Set the ultrasonic concentrator to 20cm below the melt surface. The ultrasonic output frequency is 1.6KHz, the ultrasonic output power is 700W, and the ultrasonic time is 14min. Refine and remove slag from the melt. Pour the melt into a metal mold and cool to room temperature to obtain the modified nickel alloy. Perform surface treatment on 10mm thick modified nickel alloy and 18mm thick pipeline steel plate. Combine the pipeline steel plate and modified nickel alloy using a symmetrical assembly method. Place the pipeline steel plate on the outermost side to complete the assembly. Weld the assembled modified nickel alloy and pipeline steel plate to seal the edges and perform vacuum treatment. The vacuum degree of the vacuum treatment is not less than 10. -2 Pa was used to prepare a composite billet. The composite billet was heated to 1250℃ at a heating rate of 10℃ / min and held for 10 hours before rough rolling. After rough rolling, the temperature of the composite billet reached 880℃ before finish rolling. The finished product specifications were 3+24.5mm. After finish rolling, the billet was cooled. The composite billet after finish rolling and cooling was first hot straightened and then placed at 660℃ for heat treatment. After heat treatment, it was cut, separated into plates, leveled, polished, and inspected before being printed, packaged, and shipped to obtain a nickel-based rolled composite plate.

[0044] Comparative Example 1:

[0045] The preparation method of the nickel-based rolled composite plate in Comparative Example 1 differs from that in Example 2 in that step (1) is omitted, and step (3) is modified as follows: the graphite crucible is preheated to 400°C in a pit-type resistance furnace, pure nickel blocks and aluminum-germanium modified nickel alloy are placed in the crucible at a mass ratio of 1:2.1 and heated to 1450°C, the ultrasonic concentrator of the ultrasonic device is preheated to 350°C, and the ultrasonic concentrator is placed in the melt for ultrasonic treatment. The ultrasonic concentrator is set to be 18 cm below the surface of the melt, and the ultrasonic output frequency is 1.5 kHz. The acoustic output power is 650W, the ultrasonic time is 15 minutes, the melt is refined and slag removed, poured into a metal mold, and cooled to room temperature to obtain a modified nickel alloy. A 10mm thick modified nickel alloy and an 18mm thick pipeline steel plate are surface-treated, and the pipeline steel plate and modified nickel alloy are combined using a symmetrical assembly method, with the pipeline steel plate placed on the outermost side to complete the assembly. The assembled modified nickel alloy and pipeline steel plate are welded and sealed, and then vacuum-treated, with a vacuum degree of not less than 10. -2Pa was used to prepare a composite billet. The composite billet was heated to 1100℃ at a heating rate of 10℃ / min and held at that temperature for 90 hours before rough rolling. Immediately after rough rolling, the composite billet was heated to 1200℃ for finish rolling. After finish rolling, it was cooled. The composite billet after finish rolling and cooling was first hot-straightened, and then placed at 800℃ for heat treatment. After heat treatment, it was cut, separated into plates, leveled, surface polished, and inspected before being printed, packaged, and shipped to obtain a nickel-based rolled composite plate. The remaining steps were the same as in Example 2.

[0046] Comparative Example 2:

[0047] The preparation method of the nickel-based rolled composite plate in Comparative Example 2 differs from that in Example 2 in that step (2) is omitted, and step (3) is modified as follows: the graphite crucible is preheated to 400°C in a pit-type resistance furnace, rare earth-nickel master alloy and pure nickel blocks are placed in the crucible at a mass ratio of 1:2.1 and heated to 1450°C, the ultrasonic concentrator of the ultrasonic device is preheated to 350°C, and the ultrasonic concentrator is placed in the melt for ultrasonic treatment. The ultrasonic concentrator is set to be 18 cm below the melt surface, and the ultrasonic output frequency is 1.5 kHz. The acoustic output power is 650W, the ultrasonic time is 15 minutes, the melt is refined and slag removed, poured into a metal mold, and cooled to room temperature to obtain a modified nickel alloy. A 10mm thick modified nickel alloy and an 18mm thick pipeline steel plate are surface-treated, and the pipeline steel plate and modified nickel alloy are combined using a symmetrical assembly method, with the pipeline steel plate placed on the outermost side to complete the assembly. The assembled modified nickel alloy and pipeline steel plate are welded and sealed, and then vacuum-treated, with a vacuum degree of not less than 10. -2 Pa was used to prepare a composite billet. The composite billet was heated to 1100℃ at a heating rate of 10℃ / min and held at that temperature for 90 hours before rough rolling. Immediately after rough rolling, the composite billet was heated to 1200℃ for finish rolling. After finish rolling, it was cooled. The composite billet after finish rolling and cooling was first hot-straightened, and then placed at 800℃ for heat treatment. After heat treatment, it was cut, separated into plates, leveled, surface polished, and inspected before being printed, packaged, and shipped to obtain a nickel-based rolled composite plate. The remaining steps were the same as in Example 2.

[0048] Test Example 1

[0049] Mechanical property testing

[0050] Test method: The Vickers hardness of the examples and comparative examples was tested using a micro Vickers hardness tester. The loading pressure was 10N and the holding time was 15s. 20 data points were tested and the average value was calculated.

[0051] Shear specimens were prepared in accordance with GB / T6396-2008. The mechanical properties of the shear specimens were tested using a universal tensile testing machine (model INSTRON5969), and the shear strength, yield strength, and interfacial bond strength were statistically analyzed.

[0052] Refer to ASTM G28 A method to test the intergranular corrosion rate of the coating;

[0053] The results are shown in Table 1.

[0054] Table 1

[0055]

[0056] A comparison of the experimental data from Examples 1-3 and Comparative Examples 1-2 in Table 1 reveals that the nickel-based rolled composite plate prepared by this invention has good mechanical properties.

[0057] By comparison, the hardness of Examples 1-3 is greater than that of Comparative Example 1, indicating that the rare earth-nickel master alloy is prepared by melting and mixing pure nickel blocks and ytterbium powder and using high-energy ultrasonic method. The addition of ytterbium powder can refine the grains. The high-energy ultrasonic method can uniformly disperse ytterbium powder in the nickel-based alloy, which helps to hinder dislocation movement and grain boundary slip, and at the same time reduce the atomic diffusion rate in the matrix, thereby achieving the dispersion strengthening effect of nickel-based alloy and giving nickel-based rolled composite plate excellent mechanical properties.

[0058] Test Example 2

[0059] Corrosion resistance test

[0060] Test Method: The corrosion resistance of the examples and comparative examples was tested using electrochemical impedance spectroscopy. A Gamry Interface 1000 electrochemical workstation was used, with the examples and comparative examples as the working electrodes, and the working area was 1 cm². 2 A platinum electrode was used as the counter electrode, and a saturated calomel electrode as the reference electrode. The open-circuit potential of this three-electrode system was measured in a 3.5% NaCl solution for 1800 s. Once the open-circuit potential stabilized, the system reached a steady state. Electrochemical impedance spectroscopy was then measured, with parameters set to an amplitude of 10 mV and a frequency range of 100 kHz to 0.01 Hz. The results are shown in Table 2.

[0061] Table 2

[0062]

[0063] A comparison of the experimental data from Examples 1-3 and Comparative Examples 1-2 in Table 2 reveals that the nickel-based rolled composite plate prepared by this invention has good corrosion resistance.

[0064] By comparison, the charge transfer resistance of Examples 1-3 is greater than that of Comparative Example 1, indicating that the rare earth-nickel master alloy is prepared by melting and mixing pure nickel blocks and ytterbium powder and using high-energy ultrasonic method. The addition of ytterbium powder can refine the grains. The high-energy ultrasonic method can uniformly disperse ytterbium powder in the nickel-based alloy, which helps to hinder dislocation movement and grain boundary slip, and at the same time reduce the atomic diffusion rate in the matrix, thereby achieving the dispersion strengthening effect of nickel-based alloy, inhibiting grain boundary corrosion, and giving nickel-based rolled composite plates excellent corrosion resistance.

[0065] By comparison, the charge transfer resistance of Examples 1-3 is greater than that of Comparative Example 2, indicating that the aluminum-germanium modified nickel alloy is prepared by ball milling, pressing and sintering using nickel powder, aluminum powder and germanium powder as raw materials. The addition of Ge element reduces the migration rate of Ni element from the matrix to the surface. Al element has a smaller atomic radius and a relatively faster migration rate compared to other metal elements, making it easier to contact oxygen in the air, thereby forming a complete aluminum oxide film on the alloy surface, which hinders further oxidation by oxygen and improves the corrosion resistance of the alloy.

[0066] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A nickel-based rolled composite plate, characterized in that, The nickel-based rolled composite plate is produced by vacuum rolling composite method of modified nickel alloy and pipeline steel plate; The preparation method of the nickel-based rolled composite plate includes the following preparation steps: S1. Surface-treat the 22mm thick modified nickel alloy and the 180mm thick pipeline steel plate. Combine the pipeline steel plate and the modified nickel alloy using a symmetrical assembly method, placing the pipeline steel plate on the outermost side to complete the assembly. S2. Weld and seal the assembled modified nickel alloy and pipeline steel plates, and then perform vacuum treatment. The vacuum degree of the vacuum treatment shall not be less than 10. -2 Pa, to obtain a composite blank; S3. Heat the composite billet to 1150~1250℃ at a heating rate of 10℃ / min, hold it at that temperature for 8~10h and then start rough rolling. Immediately after rough rolling, heat the composite billet to 800~1500℃ and start finish rolling. After finish rolling, cool it down. S4. After the composite billet has been cooled by precision rolling, it is first subjected to hot straightening, and then placed at a temperature of 500-920℃ for heat treatment. After the heat treatment is completed, it is cut, separated into plates, leveled, polished and inspected, and then printed, packaged and shipped to obtain nickel-based rolled composite plates.

2. The nickel-based rolled composite plate according to claim 1, characterized in that, The modified nickel alloy is prepared by melting and mixing rare earth-nickel master alloy and aluminum-germanium modified nickel alloy and then using a high-energy ultrasonic method. The rare earth-nickel master alloy is prepared by melting and mixing pure nickel blocks and ytterbium powder and then using a high-energy ultrasonic method. The aluminum-germanium modified nickel alloy is prepared by using nickel powder, aluminum powder, and germanium powder as raw materials and then ball milling, pressing, and sintering.

3. The nickel-based rolled composite plate according to claim 1, characterized in that, The modified nickel alloy is prepared using the following steps: (1) Preheat the graphite crucible to 500~520℃, put in pure nickel blocks, heat to 1400~1500℃, stir at 200~300r / min for 10~12min, add ytterbium powder at 0.06~0.08 times the mass of pure nickel blocks, continue stirring for 20~30min, preheat the ultrasonic concentrator of the ultrasonic device to 300~400℃, place the ultrasonic concentrator in the melt for ultrasonic treatment, refine and remove slag from the melt, pour it into a metal mold, cool to room temperature, and obtain rare earth-nickel master alloy; (2) Mix the powder and polyethylene glycol at a mass ratio of 1:(0.006~0.008) evenly, place them in a mold, put the mold on a press, apply a pressure of 550~560MPa, hold for 2~3min to obtain a blank; place the blank in a sintering furnace, heat from room temperature to 350~360℃ at a heating rate of 10℃ / min, hold for 2~3h, heat to 1250~1260℃ at a heating rate of 5℃ / min, hold for 2~3h, cool to room temperature to obtain an aluminum-germanium modified nickel alloy; (3) Preheat the graphite crucible to 380~420℃ in a pit-type resistance furnace. Place the rare earth-nickel master alloy and aluminum-germanium modified nickel alloy into the crucible at a mass ratio of 1:(2~2.2) and heat it to 1400~1500℃. Preheat the ultrasonic concentrator of the ultrasonic device to 300~400℃. Place the ultrasonic concentrator in the melt for ultrasonic treatment. Refine and remove slag from the melt. Pour it into a metal mold and cool it to room temperature to obtain the modified nickel alloy.

4. The nickel-based rolled composite plate according to claim 3, characterized in that, The process parameters for ultrasonic treatment in step (1) are as follows: the ultrasonic concentrator is set 16-20 cm below the surface of the melt, the ultrasonic output frequency is 1.4-1.6 kHz, the ultrasonic output power is 600-700 W, and the ultrasonic time is 10-12 min; the ytterbium powder has a mesh size of 400 mesh.

5. The nickel-based rolled composite plate according to claim 3, characterized in that, The method for preparing the mixed powder in step (2) is as follows: mix nickel powder, aluminum powder and germanium powder evenly, place them in a ball mill, and ball mill under argon protection. Set the ball-to-material ratio to (9~10):1, the ball milling speed to 140~160 r / min, and the ball milling time to 7~9 h to obtain the mixed powder.

6. The nickel-based rolled composite plate according to claim 5, characterized in that, The mass ratio of nickel powder, aluminum powder, and germanium powder is 1:(0.06~0.08):(0.04~0.06).

7. The nickel-based rolled composite plate according to claim 5, characterized in that, The nickel powder has a mesh size of 300, the aluminum powder has a mesh size of 400, and the germanium powder has a mesh size of 600.

8. The nickel-based rolled composite plate according to claim 3, characterized in that, The polyethylene glycol used in step (2) is PEG2000.

9. The nickel-based rolled composite plate according to claim 3, characterized in that, The process parameters for ultrasonic treatment in step (3) are as follows: the ultrasonic concentrator is set 16-20 cm below the surface of the melt, the ultrasonic output frequency is 1.4-1.6 kHz, the ultrasonic output power is 600-700 W, and the ultrasonic time is 14-16 min.

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