A method and device for pulse laser-assisted additive manufacturing of nickel-based superalloy microstructure performance regulation

Abstract

The present application relates to a kind of pulse laser assisted additive manufacturing nickel-based superalloy structure performance regulation and control method and device, belong to additive manufacturing technical field, the method includes steps: control LPBF forming device's sealed forming cabin oxygen content, nickel-based superalloy powder is laid flat to the base plate of sealed forming cabin;Pulse laser, continuous laser output laser beam, pulse laser beam and continuous laser beam are coupled by the way of polarization beam combination or wavelength beam combination, after the focal length of coupled laser beam is adjusted, the nickel-based superalloy powder on base plate is fused and formed.The method of the present application realizes in-situ synchronous disturbance to molten pool in the process of LPBF additive manufacturing by coupling pulse laser and continuous laser into coaxial facula, can accurately control the solidification behavior of nickel-based superalloy, effectively break the epitaxial growth of columnar crystal, promote the formation of small equiaxed crystal, be conducive to reducing the anisotropy and cracking risk of material.

Description

Technical Field

[0001] This invention relates to the field of additive manufacturing technology, and specifically to a method and apparatus for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing. Background Technology

[0002] Laser-assisted powder bed fusion (LPBF) additive manufacturing technology suffers from severe anisotropy in its grain structure due to the layer-by-layer scanning powder deposition process. High-temperature alloys formed by LPBF exhibit numerous coarse columnar crystals, leading to susceptibility to cracking and anisotropic mechanical properties. Research indicates that introducing an additional energy field to disturb the solidification pool during additive manufacturing, thereby regulating the solidification process, can promote grain refinement, reduce columnar crystal formation, and ultimately decrease material anisotropy and cracking risk.

[0003] Currently, the main external fields introduced for controlling the solidification behavior of LPBF additive manufacturing processes are magnetic fields and ultrasonic fields. However, these methods have two main problems. First, these energy fields are difficult to focus, making it impossible to precisely control their area of ​​effect, and consequently, to accurately control their effect on the solidification of the molten pool. Second, due to the limited space in the LPBF forming chamber, it is difficult to integrate ultrasonic and magnetic field generators into the LPBF equipment, further hindering the feasibility of external field regulation of the LPBF forming and solidification process. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method and apparatus for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing.

[0005] The main technical problems solved by this invention include: how to reduce the formation of columnar crystals during the solidification of LPBF molten pool, thereby reducing the anisotropy and cracking risk of the material.

[0006] The technical solution of the present invention is as follows:

[0007] This invention provides a method for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing, comprising the following steps:

[0008] (1) Control the oxygen content in the sealed forming chamber of the LPBF forming device and spread the nickel-based high-temperature alloy powder evenly on the substrate of the sealed forming chamber.

[0009] (2) Control the output laser beams of the pulsed laser and the continuous laser, and couple the pulsed laser beam and the continuous laser beam into a coaxial spot by means of polarization beam combining or wavelength beam combining. After adjusting the focal length of the coupled laser beam, melt and form the nickel-based high-temperature alloy powder on the substrate.

[0010] According to a preferred embodiment of the present invention, the specific method of polarization beam combining is as follows: a pulsed laser beam passes sequentially through a collimating lens A, a beam expander A, a thin-film polarizer A, and a half-wave plate A to output a horizontally polarized pulsed laser beam; a continuous laser beam passes sequentially through a collimating lens B, a beam expander B, a thin-film polarizer B, and a half-wave plate B to output a vertically polarized continuous laser beam; and the horizontally polarized pulsed laser beam and the vertically polarized continuous laser beam are coupled into a coaxial laser beam through a polarization beam splitter.

[0011] According to a preferred embodiment of the present invention, the specific method for wavelength beam combining is as follows: a pulsed laser beam passes sequentially through collimating lens A and beam expander A to output a collimated and expanded pulsed laser beam; a continuous laser beam passes sequentially through collimating lens B and beam expander B to output a collimated and expanded continuous laser beam; and the collimated and expanded pulsed laser beam and the collimated and expanded continuous laser beam are coupled to coaxial laser beams through a dichroic mirror.

[0012] According to a preferred embodiment of the present invention, the particle size of the nickel-based superalloy powder is on the order of micrometers.

[0013] According to a preferred embodiment of the present invention, the process parameters of the pulsed laser are set as follows: power of 100-1000 W, pulse width of 10-2000 ns, repetition frequency of 1-400 kHz, and spot diameter of 50-200 μm.

[0014] According to a preferred embodiment of the present invention, the process parameters set for the continuous laser are: power of 100-4000 W and spot diameter of 50-200 μm.

[0015] In this invention, the diameter of the pulsed laser beam spot is larger than the width of the molten pool generated under the continuous laser beam spot, which satisfies the requirement of the continuous laser beam melting nickel-based superalloy powder to form a molten pool. The pulsed laser beam generates an impact force to synchronously disturb the molten pool and regulate the solidification behavior of the nickel-based superalloy.

[0016] According to a preferred embodiment of the present invention, the process parameters of the coupling laser beam are set as follows: the scanning speed of the coupling laser beam is 500-1500 mm / s, and the rotation angle of the coupling laser beam during interlayer scanning is 67° or 90°.

[0017] The present invention also provides an apparatus for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing, comprising a computer control system, a pulsed laser, a continuous laser, a coupling optical path system, and an LPBF forming device; the pulsed laser and the continuous laser are respectively communicatively connected to the computer control system, the coupling optical path system is disposed on the output side of the pulsed laser and the continuous laser, and the LPBF forming device is disposed on the output side of the coupling optical path system.

[0018] According to a preferred embodiment of the present invention, the coupled optical path system includes a collimating lens A, a collimating lens B, a beam expander A, a beam expander B, a thin-film polarizer A, a thin-film polarizer B, a half-wave plate A, a half-wave plate B, a polarizing beam splitter prism, a galvanometer system, and an F-θ lens; the output side of the pulsed laser is sequentially provided with a collimating lens A, a beam expander A, a thin-film polarizer A, and a half-wave plate A, and the output side of the continuous laser is sequentially provided with a collimating lens B, a beam expander B, a thin-film polarizer B, and a half-wave plate B; the output sides of the half-wave plate A and the half-wave plate B are sequentially provided with a polarizing beam splitter prism, a galvanometer system, and an F-θ lens.

[0019] According to a preferred embodiment of the present invention, the coupled optical path system includes a collimating lens A, a collimating lens B, a beam expander A, a beam expander B, a dichroic mirror, a galvanometer system, and an F-θ lens; the output side of the pulsed laser is sequentially provided with collimating lens A and beam expander A, and the output side of the continuous laser is sequentially provided with collimating lens B and beam expander B; the output sides of beam expander A and beam expander B are sequentially provided with a dichroic mirror, a galvanometer system, and an F-θ lens.

[0020] According to a preferred embodiment of the present invention, the LPBF forming apparatus includes a powder spreading scraper, a powder supply cylinder, a powder recovery system, and a sealed forming chamber. The powder spreading scraper, powder supply cylinder, forming cylinder, and powder recovery system are all disposed within the sealed forming chamber. The forming cylinder is disposed within the sealed forming chamber at a position corresponding to the F-θ lens. The powder supply cylinder and the powder recovery system are respectively disposed on both sides of the forming cylinder. A forming platform and a substrate are sequentially disposed from bottom to top within the forming cylinder. A powder supply platform is disposed within the powder supply cylinder. The powder spreading scraper is disposed above the forming cylinder and the powder supply cylinder and reciprocates above the forming cylinder and the powder supply cylinder to spread the nickel-based high-temperature alloy powder in the powder supply cylinder onto the entire plane of the substrate.

[0021] The technical features and beneficial effects of this invention are as follows:

[0022] 1. The method of the present invention achieves in-situ synchronous disturbance of the molten pool during LPBF additive manufacturing by coupling pulsed laser and continuous laser into a coaxial spot. This enables precise control of the solidification behavior of nickel-based superalloys, effectively breaks the epitaxial growth of columnar crystals, promotes the formation of fine equiaxed crystals, and helps reduce the anisotropy and cracking risk of the material.

[0023] 2. The method of the present invention uses pulsed laser as a disturbance source, and utilizes its high energy density and instantaneous impact characteristics to generate plasma impact force in the molten pool. It can achieve efficient control of microstructure without changing the original LPBF process path, and has good process compatibility and controllability.

[0024] 3. The method of the present invention combines pulsed laser and continuous laser into a coaxial beam by polarization beam combining or wavelength beam combining, which solves the problems of difficulty in focusing and spatial integration of traditional energy fields (such as magnetic fields and ultrasonic fields), significantly improves the control accuracy and system integration, and is suitable for the transformation and upgrading of existing LPBF equipment. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the device for controlling the microstructure and properties of nickel-based superalloys in embodiment 3 of the present invention;

[0026] Figure 2 This is a schematic diagram of the device for controlling the microstructure and properties of nickel-based superalloys in embodiment 4 of the present invention;

[0027] The components include: 1. Computer control system; 2. Pulsed laser; 3. Continuous laser; 4. Pulsed laser beam; 5. Continuous laser beam; 6. Collimating lens A; 7. Collimating lens B; 8. Collimated pulsed laser beam; 9. Collimated continuous laser beam; 10. Beam expander A; 11. Beam expander B; 12. Collimated and expanded pulsed laser beam; 13. Collimated and expanded continuous laser beam; 14. Thin-film polarizer A; 15. Thin-film polarizer B; 16. Linearly polarized pulsed laser beam; 17. Linearly polarized continuous laser beam; 18. Half-wave plate A. ; 19. Half-wave plate B; 20. Horizontally polarized pulsed laser beam; 21. Vertically polarized continuous laser beam; 22. Polarizing beam splitter; 23. Coupled laser beam; 24. Galvanometer system; 25. F-θ lens; 26. Focusing coupled laser beam; 27. Powder spreading scraper; 28. Nickel-based high-temperature alloy powder; 29. ​​Powder supply cylinder; 30. Powder supply platform; 31. Forming cylinder; 32. Formed sample; 33. Forming platform; 34. Substrate; 35. Powder recovery system; 36. Sealed forming chamber; 37. Dichroic mirror. Detailed Implementation

[0028] The present invention will be further described below with reference to embodiments and accompanying drawings, but is not limited thereto. The described embodiments are some embodiments of the present invention. Based on these embodiments, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other. Unless otherwise specified in the embodiments of the present invention, all techniques existing in the art can be used.

[0030] Example 1

[0031] This embodiment provides a method for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing, specifically including the following steps:

[0032] (1) Select IN939 nickel-based high-temperature alloy powder 28 with a particle size of 15-53 μm for forming; establish a 10 mm × 10 mm × 10 mm cube model and slice it with a thickness of 40 μm using computer software; import the model into the computer control system 1; place IN939 nickel-based high-temperature alloy powder 28 in the powder supply cylinder 29, introduce argon gas, and keep the oxygen content in the sealed forming chamber 36 below 300 ppm.

[0033] (2) Using computer control system 1, set the power of pulsed laser 2 to 200 W, pulse width to 80 ns, repetition frequency to 400 kHz, and spot diameter to 100 μm; and the power of continuous laser 3 to 200 W and spot diameter to 80 μm.

[0034] Pulsed laser 2 outputs a pulsed laser beam 4. The pulsed laser beam 4 passes through collimating lens A6 to output a collimated pulsed laser beam 8. The collimated pulsed laser beam 8 passes through beam expander A10 to output a collimated and expanded pulsed laser beam 12. The collimated and expanded pulsed laser beam 12 passes through thin-film polarizer A14 to output a linearly polarized pulsed laser beam 16. The linearly polarized pulsed laser beam 16 passes through half-wave plate A18 to output a horizontally polarized pulsed laser beam 20. Simultaneously, continuous laser 3 outputs a continuous laser beam 5. The continuous laser beam 5 passes through collimating lens B7 to output a collimated continuous laser beam 9. The collimated continuous laser beam 9 passes through a collimating lens B10 to output a collimated continuous laser beam 9. The beam expander B11 outputs a collimated and expanded continuous laser beam 13. The collimated and expanded continuous laser beam 13 outputs a linearly polarized continuous laser beam 17 through a thin-film polarizer B15. The linearly polarized continuous laser beam 17 outputs a vertically polarized continuous laser beam 21 through a half-wave plate B19. The horizontally polarized pulsed laser beam 20 and the vertically polarized continuous laser beam 21 output a coaxial coupled laser beam 23 through a polarizing beam splitter 22. The movement of the coupled laser beam 23 is controlled by a galvanometer system 24, and the focused coupled laser beam 26 is output through an F-θ lens 25 to reach the designated position on the substrate 34.

[0035] The coupling laser process parameters were set as follows: scanning speed of 1000 mm / s, and coupling laser rotation angle of 67° during interlayer scanning;

[0036] In the coupled laser working plane, the continuous laser rapidly raises the temperature of the IN939 nickel-based superalloy powder 28 through the high-energy laser beam, causing it to melt and form a molten pool. The pulsed laser generates plasma in the molten pool, creating an impact force that disturbs the molten pool, affecting the solidification path of the IN939 nickel-based superalloy and breaking the columnar epitaxial growth to form fine equiaxed crystals.

[0037] In this embodiment, the diameter of the pulsed laser spot is larger than the width of the molten pool generated by the continuous laser spot, which meets the requirement of continuous laser melting of nickel-based superalloy powder 28 to form a molten pool. The pulsed laser generates an impact force to synchronously disturb the molten pool and regulate the solidification behavior of the nickel-based superalloy.

[0038] The width of the molten pool generated by continuous laser is calculated using the dimensionless temperature field function g:

[0039] ;

[0040] Where x, y, z are dimensionless coordinates of the temperature field generated by continuous laser, p is the Peckley number, and t is the dimensionless time. When g reaches the dimensionless melting temperature of the material... ,in, The enthalpy is dimensionless and depends on the laser spot diameter, as well as the absorptivity, density, specific heat capacity, enthalpy of fusion, and thermal diffusivity of the material being melted. In this case, x, y, and z are the coordinates of the molten pool boundary, and x is the width of the molten pool. Where d is the laser spot diameter, the molten pool width is proportional to the laser spot diameter, and the proportionality coefficient depends on the dimensionless enthalpy, Peckley number and laser process parameters. Under the preferred parameters, the molten pool is generally greater than 1 when it is in conduction mode. Therefore, the diameter of the pulsed laser spot should be greater than the diameter of the continuous laser spot.

[0041] Example 2

[0042] This embodiment provides a method for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing, as described in Embodiment 1, except that:

[0043] In step (1), the thickness of the slice is 30 μm;

[0044] In step (2), the computer control system 1 is used to set the power of the pulsed laser 2 to 100W, the pulse width to 20 ns, the repetition frequency to 120 kHz, and the spot diameter to 180 μm; the power of the continuous laser 3 is set to 100 W and the spot diameter to 100 μm.

[0045] Pulsed laser 2 outputs pulsed laser beam 4, which is collimated into a collimated pulsed laser beam 8 through collimating lens A6. Collimated pulsed laser beam 8 is then collimated into a collimated expanded pulsed laser beam 12 through beam expander A10. Simultaneously, continuous laser 3 outputs continuous laser beam 5, which is collimated into a collimated continuous laser beam 9 through collimating lens B7. Collimated continuous laser beam 9 is then collimated into a collimated expanded continuous laser beam 13 through beam expander B11. Collimated expanded pulsed laser beam 12 and collimated expanded continuous laser beam 13 are then output as a coaxial coupled laser beam 23 through dichroic mirror 37. The movement of coupled laser beam 23 is controlled by galvanometer system 24, and focused coupled laser beam 26 is output through F-θ lens 25 to reach a designated position on substrate 34.

[0046] The coupling laser process parameters were set as follows: scanning speed of 500 mm / s, and coupling laser rotation angle of 90° during interlayer scanning.

[0047] Example 3

[0048] This embodiment provides a device for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing, such as... Figure 1 As shown, the device includes a computer control system 1, a pulsed laser 2, a continuous laser 3, a coupling optical path system, and an LPBF forming device; the pulsed laser 2 and the continuous laser 3 are respectively connected to the computer control system 1 for communication, the coupling optical path system is set on the output side of the pulsed laser 2 and the continuous laser 3, and the LPBF forming device is set on the output side of the coupling optical path system.

[0049] In this embodiment, the coupled optical path system includes a collimating lens A6, a collimating lens B7, a beam expander A10, a beam expander B11, a thin-film polarizer A14, a thin-film polarizer B15, a half-wave plate A18, a half-wave plate B19, a polarizing beam splitter 22, a galvanometer system 24, and an F-θ lens 25. The output side of the pulsed laser 2 is sequentially provided with a collimating lens A6, a beam expander A10, a thin-film polarizer A14, and a half-wave plate A18. The output side of the continuous laser 3 is sequentially provided with a collimating lens B7, a beam expander B11, a thin-film polarizer B15, and a half-wave plate B19. The output sides of the half-wave plates A18 and B19 are sequentially provided with a polarizing beam splitter 22, a galvanometer system 24, and an F-θ lens 25.

[0050] In this embodiment, the LPBF forming device includes a powder spreading scraper 27, a powder supply cylinder 29, a powder recovery system 35, and a sealed forming chamber 36. The powder spreading scraper 27, the powder supply cylinder 29, the forming cylinder 31, and the powder recovery system 35 are all disposed within the sealed forming chamber 36. The forming cylinder 31 is disposed within the sealed forming chamber 36 at the position corresponding to the F-θ lens 25. The powder supply cylinder 29 and the powder recovery system 35 are respectively disposed on both sides of the forming cylinder 31. From bottom to top, a forming platform 33 and a substrate 34 are disposed in the forming cylinder 31. A powder supply platform 30 is disposed within the powder supply cylinder 29. The powder spreading scraper 27 is disposed above the forming cylinder 31 and the powder supply cylinder 29, and moves back and forth above the forming cylinder 31 and the powder supply cylinder 29 to spread the nickel-based high-temperature alloy powder 28 in the powder supply cylinder 29 onto the entire plane of the substrate 34.

[0051] The computer control system 1, which imports the slice model file, controls the forming platform 33 after mounting the substrate 34 to descend, controls the nickel-based superalloy powder 28 in the powder supply platform 30 to rise, controls the powder spreading scraper 27 to spread the nickel-based superalloy powder 28 onto the entire plane of the substrate 34, controls the galvanometer system 24 to move and couple the laser beam, and uses the F-θ lens 25 to focus and couple the laser beam 26 to form the nickel-based superalloy powder 28 on the substrate 34, thus obtaining the formed sample 32.

[0052] Example 4

[0053] This embodiment provides a device for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing, such as... Figure 2 As shown, the difference from Example 3 is that:

[0054] The coupled optical path system includes a collimating mirror A6, a collimating mirror B7, a beam expander A10, a beam expander B11, a dichroic mirror 37, a galvanometer system 24, and an F-θ lens 25. The output side of the pulsed laser 2 is provided with a collimating mirror A6 and a beam expander A10 in sequence, and the output side of the continuous laser 3 is provided with a collimating mirror B7 and a beam expander B11 in sequence. The output sides of beam expanders A10 and B11 are provided with a dichroic mirror 37, a galvanometer system 24, and an F-θ lens 25 in sequence.

[0055] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing, characterized in that, Including the following steps: (1) Control the oxygen content in the sealed forming chamber of the LPBF forming device and spread the nickel-based high-temperature alloy powder evenly on the substrate of the sealed forming chamber. (2) Control the output laser beams of the pulsed laser and the continuous laser, and couple the pulsed laser beam and the continuous laser beam into a coaxial spot by means of polarization beam combining or wavelength beam combining. After adjusting the focal length of the coupled laser beam, melt and shape the nickel-based high-temperature alloy powder on the substrate. The specific method of polarization beam combining is as follows: the pulsed laser beam passes sequentially through collimating lens A, beam expander A, thin-film polarizer A, and half-wave plate A to output a horizontally polarized pulsed laser beam; the continuous laser beam passes sequentially through collimating lens B, beam expander B, thin-film polarizer B, and half-wave plate B to output a vertically polarized continuous laser beam; the horizontally polarized pulsed laser beam and the vertically polarized continuous laser beam are coupled into a coaxial laser beam through a polarization beam splitter. The specific method for wavelength beam combining is as follows: the pulsed laser beam passes sequentially through collimating lens A and beam expander A to output a collimated and expanded pulsed laser beam; the continuous laser beam passes sequentially through collimating lens B and beam expander B to output a collimated and expanded continuous laser beam; the collimated and expanded pulsed laser beam and the collimated and expanded continuous laser beam are output as a coaxial coupled laser beam through a dichroic mirror.

2. The method for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing according to claim 1, characterized in that, The process parameters set for the pulsed laser are: power of 100-1000 W, pulse width of 10-2000 ns, repetition frequency of 1-400 kHz, and spot diameter of 50-200 μm.

3. The method for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing according to claim 1, characterized in that, The process parameters set for the continuous laser are: power of 100-4000 W and spot diameter of 50-200 μm.

4. The method for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing according to claim 1, characterized in that, The process parameters of the coupling laser beam are set as follows: the scanning speed of the coupling laser beam is 500-1500 mm / s, and the rotation angle of the coupling laser beam during interlayer scanning is 67° or 90°.

5. An apparatus for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing, used in the method for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing as described in claim 1, characterized in that... It includes a computer control system, a pulsed laser, a continuous laser, a coupling optical path system, and an LPBF forming device; the pulsed laser and the continuous laser are respectively communicatively connected to the computer control system, the coupling optical path system is located on the output side of the pulsed laser and the continuous laser, and the LPBF forming device is located on the output side of the coupling optical path system.

6. The apparatus for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing according to claim 5, characterized in that, The coupled optical path system includes collimating lens A, collimating lens B, beam expander A, beam expander B, thin-film polarizer A, thin-film polarizer B, half-wave plate A, half-wave plate B, polarizing beam splitter prism, galvanometer system, and F-θ lens; the output side of the pulsed laser is sequentially provided with collimating lens A, beam expander A, thin-film polarizer A, and half-wave plate A, and the output side of the continuous laser is sequentially provided with collimating lens B, beam expander B, thin-film polarizer B, and half-wave plate B; the output sides of half-wave plate A and half-wave plate B are sequentially provided with polarizing beam splitter prism, galvanometer system, and F-θ lens.

7. The apparatus for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing according to claim 5, characterized in that, The coupled optical path system includes a collimating lens A, a collimating lens B, a beam expander A, a beam expander B, a dichroic mirror, a galvanometer system, and an F-θ lens; the output side of the pulsed laser is provided with collimating lens A and beam expander A in sequence, the output side of the continuous laser is provided with collimating lens B and beam expander B in sequence, and the output sides of beam expander A and beam expander B are provided with a dichroic mirror, a galvanometer system, and an F-θ lens in sequence.

8. The apparatus for controlling the microstructure and properties of nickel-based superalloys in pulsed laser-assisted additive manufacturing according to claim 6 or 7, characterized in that, The LPBF forming apparatus includes a powder spreading scraper, a powder supply cylinder, a powder recovery system, and a sealed forming chamber. The powder spreading scraper, powder supply cylinder, forming cylinder, and powder recovery system are all located inside the sealed forming chamber. The forming cylinder is located inside the sealed forming chamber at the position corresponding to the F-θ lens. The powder supply cylinder and the powder recovery system are respectively located on both sides of the forming cylinder. From bottom to top, a forming platform and a substrate are arranged in sequence inside the forming cylinder. A powder supply platform is arranged inside the powder supply cylinder. The powder spreading scraper is located above the forming cylinder and the powder supply cylinder and moves back and forth above the forming cylinder and the powder supply cylinder to spread the nickel-based high-temperature alloy powder in the powder supply cylinder onto the entire plane of the substrate.

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