Selective laser melting manufacturing process of nickel-based superalloy blade with complex structure

Abstract

The invention discloses a selective laser melting manufacturing process of a nickel-based superalloy blade with a complex structure, and relates to the technical field of superalloy processing. The method comprises the following steps: preparing nickel-based high-temperature alloy powder; the method comprises the following steps: constructing a three-dimensional model of a to-be-formed blade with a complex structure, carrying out layering treatment on the three-dimensional model of the blade, and importing parameters of the three-dimensional model into selective laser melting equipment; setting filling process parameters and contour process parameters; laser melting forming is carried out in a laser scanning mode, and the laser scanning mode comprises the steps that firstly, the filling part in each layer is scanned, and then one-time single-contour laser scanning is carried out on the layer; according to the selective laser melting forming method, selective laser melting forming manufacturing of IN718Plus nickel-based high-temperature alloy blades with complex structures can be achieved by exploring optimized technological parameters.

Description

Technical Field

[0001] The present invention relates to the technical field of high-temperature alloy processing, and in particular to a selective laser melting manufacturing process for a nickel-based high-temperature alloy blade with a complex structure. Background Art

[0002] In the field of modern aerospace and energy, nickel-based superalloys are widely used in the manufacture of key components such as turbine blades due to their excellent high-temperature strength, oxidation resistance and corrosion resistance. Turbine blade structures are currently manufactured by machining and polishing traditional alloys ingots in a subtractive manner. With the continuous improvement of engine performance and efficiency requirements, traditional manufacturing processes have been unable to meet the design and production needs of complex structure blades. Therefore, it is particularly important to develop new manufacturing processes to achieve efficient and high-quality forming of complex structure blades. Selective Laser Melting (SLM), as an advanced additive manufacturing technology, can construct complex three-dimensional structures by melting metal powder layer by layer, with the advantages of high design freedom and high material utilization. Selective laser melting technology shows good application prospects in the manufacture of nickel-based superalloys, especially in the manufacture of blades with complex geometries, which can effectively reduce material waste and processing time. However, nickel-based superalloys encounter problems such as difficulty in molten pool control and thermal stress concentration during the selective laser melting process, which leads to cracks and pores in the finished product, low density, overall shape distortion, and uneven microstructure. Therefore, it is particularly necessary to study the optimization of the selective laser melting manufacturing process for complex structure blades of nickel-based high-temperature alloys. Summary of the invention

[0003] In view of the deficiencies in the above-mentioned background technology, the main purpose of the present invention is to overcome the problems of low density, shape distortion, poor surface formability and uneven microstructure of the finished product caused by mismatch of process parameters during the selective laser melting process of IN718Plus nickel-based high-temperature alloy for manufacturing complex structure blades. The present invention provides a selective laser melting manufacturing process for nickel-based high-temperature alloy complex structure blades. This method can realize the selective laser melting forming and manufacturing of IN718Plus nickel-based high-temperature alloy complex structure blades by exploring optimized process parameters. The finished product has good surface forming, no macroscopic thermal cracks, and a density of up to 99.9%.

[0004] The first object of the present invention is to provide a selective laser melting manufacturing process for a nickel-based high-temperature alloy blade with a complex structure, comprising the following steps: Formulating nickel-based high-temperature alloy powder; Construct a three-dimensional model of a blade with a complex structure to be formed, perform layered processing on the blade three-dimensional model, and import various parameters of the three-dimensional model into the selective laser melting equipment; Place nickel-based high-temperature alloy powder in a liftable powder supply cylinder, and adjust the positions of the forming cylinder and the powder supply cylinder respectively, so that the upper surface of the substrate in the forming cylinder and the upper edge of the powder in the powder supply cylinder are flush with the lower surface of the equipment scraper; Argon gas is introduced into the molding cylinder as a protective gas, and the substrate is preheated; Set filling process parameters and contour process parameters; Laser melting is performed by laser scanning, wherein the laser scanning method includes: first scanning the internal filling part of each layer, and then performing a single contour laser scan on the layer; By cyclic scanning until all scanning layers are formed, a nickel-based high-temperature alloy blade with a complex structure is obtained.

[0005] Preferably, the filling process parameters are selected as follows: laser power 135W, laser scanning rate 750mm / s, layer thickness 0.02mm, overlap spacing 0.08mm; The contour process parameters use the single contour method, the contour laser power is 135W, and the laser scanning speed is 750mm / s.

[0006] Preferably, after each layer of scanning is completed, the internal scanning direction of the next layer is rotated 67° clockwise based on the scanning direction of the previous layer.

[0007] Preferably, the laser melting forming process includes: First layer selective laser melting laser forming: Confirm the scanning area, calculate the moving distance of the scraper, and move the scraper to evenly spread the powder in the powder supply cylinder on the substrate to obtain the first layer of alloy powder; Turn on the laser and perform the first scan along the length direction of the part. After the first scan, perform the second scan at an interval of 0.08mm. The second scan direction is opposite to the first scan. Then repeat the first and second scan processes until the internal scan of the layer of the part is completed. Then perform a single scan along the outer contour of the layer of the part at the same power and scanning speed to complete the laser forming of the first layer. Second layer laser forming: The scraper is moved to evenly spread the powder in the powder supply cylinder on the surface of the first laser forming layer to obtain the second layer of alloy powder. The scanning direction is changed to start the first scan of the second layer. After the first scan of the second layer is completed, the second scan of the second layer is performed at an interval of 0.08mm. The scanning direction of the second scan of the second layer is opposite to that of the first scan. Then, the scanning process of the first and second scans of the layer is repeated until the internal scan of the layer of the part is completed. Then, a single scan is performed along the outer contour of the layer of the part at the same power and scanning speed to complete the laser forming of the second layer. The process of forming the second layer is cyclically repeated until the forming of all scanning layers is completed.

[0008] Preferably, the thickness of the first alloy powder layer is 0.02 mm; the thickness of the second alloy powder layer is 0.02 mm.

[0009] Preferably, when scanning the inner filling part of each layer, reciprocating weaving is used for scanning.

[0010] Preferably, the nickel-based high-temperature alloy raw material includes the following components in mass ratio: Cr: 17.0-21.0%, Mo: 2.50-3.10%, Nb: 5.20-5.80%, Al: 1.2-1.7%, Ti: 0.50-1.00%, Co: 8.0-20.0%, Fe: 8.0-10.0%, W: 0.80-1.50%, Ni: balance.

[0011] Preferably, the particle size of the nickel-based high-temperature alloy powder is 15-45 μm.

[0012] The second object of the present invention is to provide a nickel-based high-temperature alloy complex structure blade produced by the above process.

[0013] The third object of the present invention is to provide a nickel-based high-temperature alloy complex structure blade for use in aerospace engines.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The invention provides a selective laser melting manufacturing process for a nickel-based high-temperature alloy blade with a complex structure. The invention utilizes the selective laser melting technology to manufacture the nickel-based high-temperature alloy blade with a complex structure. The material used is IN718Plus nickel-based high-temperature alloy powder. The optimized process parameters are determined through a large number of preliminary experimental explorations: the laser power is 135W, the scanning rate is 750mm / s, the layer thickness is 0.02mm, and the overlap spacing is 0.08mm. The scanning strategy of each layer is divided into two parts. First, the inside of the layer is scanned, and a reciprocating weaving scanning strategy is adopted, that is, reciprocating scanning within the layer. After scanning the inside of each layer, a single-pass scanning is performed on the contour of the part in the layer with the same process parameters. The internal scanning direction of each subsequent layer is rotated 67° clockwise on the basis of the scanning direction of the previous layer. The scanning is cyclically performed until the forming of all the scanned layers is completed. Finally, the IN718Plus nickel-based high-temperature alloy blade with a complex structure having no macro crack pores, no shape distortion, low surface roughness, good formability, and a density of up to 99.8% is obtained.

[0015] The present invention uses a high-energy laser beam to melt powder materials based on SLM technology, and builds parts layer by layer through layered stacking. Under the action of the laser, the powder particles of each layer will melt into liquid metal and combine with the previous forming layer, and form a dense solid structure after cooling. The layer-by-layer melting method helps to reduce the existence of interlayers and gaps. SLM technology can accurately control process parameters such as laser power and scanning rate, so that the heat input during the melting process can be controlled. This adjustability is conducive to optimizing process parameters so that excessive defects such as pores and cracks can be avoided in the material during the melting and forming process, thereby improving density. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a macroscopic morphology of a nickel-based high-temperature alloy blade with a complex structure manufactured by the method of the present invention; Figure 2 The microstructure diagram of the nickel-based high-temperature alloy blade with complex structure manufactured by the method of the present invention; Figure 3 This is a Laves phase morphology of a nickel-based high-temperature alloy blade with a complex structure prepared by the method of the present invention; Figure 4 This is a diffraction pattern of a nickel-based high-temperature alloy blade with a complex structure prepared by the method of the present invention. DETAILED DESCRIPTION

[0017] In order to enable those skilled in the art to better understand and implement the technical solution of the present invention, the present invention is further described below in conjunction with specific embodiments and drawings, but the embodiments are not intended to limit the present invention.

[0018] The purpose of the present invention is to overcome the problems of low density, shape distortion, poor surface formability and uneven microstructure of the finished product caused by mismatch of process parameters in the process of selective laser melting of IN718Plus nickel-based high-temperature alloy for manufacturing complex structure blades. A selective laser melting manufacturing process for complex structure blades of nickel-based high-temperature alloy is provided. By exploring the optimized process parameters, the selective laser melting forming and manufacturing of complex structure blades of IN718Plus nickel-based high-temperature alloy can be realized. The surface of the finished product is well formed, without macroscopic thermal cracks, and the density is as high as 99.9%.

[0019] In order to achieve the above-mentioned object, the first aspect of the present invention provides a selective laser melting manufacturing process for a nickel-based high-temperature alloy complex structure blade, comprising the following steps: Formulating nickel-based high-temperature alloy powder; Construct a three-dimensional model of a blade with a complex structure to be formed, perform layered processing on the blade three-dimensional model, and import various parameters of the three-dimensional model into the selective laser melting equipment; Place nickel-based high-temperature alloy powder in a liftable powder supply cylinder, and adjust the positions of the forming cylinder and the powder supply cylinder respectively, so that the upper surface of the substrate in the forming cylinder and the upper edge of the powder in the powder supply cylinder are flush with the lower surface of the equipment scraper; Argon gas is introduced into the molding cylinder as a protective gas, and the substrate is preheated; Set filling process parameters and contour process parameters; Laser melting is performed by laser scanning, wherein the laser scanning method includes: first scanning the internal filling part of each layer, and then performing a single contour laser scan on the layer; By cyclic scanning until all scanning layers are formed, a nickel-based high-temperature alloy blade with a complex structure is obtained.

[0020] Among them, the filling process parameters are laser power 135W, laser scanning rate 750mm / s, layer thickness 0.02mm, and overlap spacing 0.08mm; The contour process parameters use the single contour method, the contour laser power is 135W, and the laser scanning speed is 750mm / s.

[0021] According to the present invention, after each layer of scanning is completed, the internal scanning direction of the next layer is rotated 67° clockwise based on the scanning direction of the previous layer.

[0022] Specifically, the laser melting forming process includes: First layer selective laser melting laser forming: Confirm the scanning area, calculate the moving distance of the scraper, and move the scraper to evenly spread the powder in the powder supply cylinder on the substrate to obtain the first layer of alloy powder; Turn on the laser and perform the first scan along the length direction of the part. After the first scan, perform the second scan at an interval of 0.08mm. The second scan direction is opposite to the first scan. Then repeat the first and second scan processes until the internal scan of the layer of the part is completed. Then perform a single scan along the outer contour of the layer of the part at the same power and scanning speed to complete the laser forming of the first layer. Second layer laser forming: The scraper is moved to evenly spread the powder in the powder supply cylinder on the surface of the first laser forming layer to obtain the second layer of alloy powder. The scanning direction is changed to start the first scan of the second layer. After the first scan of the second layer is completed, the second scan of the second layer is performed at an interval of 0.08mm. The scanning direction of the second scan of the second layer is opposite to that of the first scan. Then, the scanning process of the first and second scans of the layer is repeated until the internal scan of the layer of the part is completed. Then, a single scan is performed along the outer contour of the layer of the part at the same power and scanning speed to complete the laser forming of the second layer. The process of forming the second layer is cyclically repeated until the forming of all scanning layers is completed.

[0023] The thickness of the first alloy powder layer is 0.02 mm; the thickness of the second alloy powder layer is 0.02 mm.

[0024] When scanning the inner filling part of each layer, reciprocating weaving is used for scanning.

[0025] According to the present invention, the nickel-based high-temperature alloy raw material includes the following components by mass ratio: Cr: 17.0-21.0%, Mo: 2.50-3.10%, Nb: 5.20-5.80%, Al: 1.2-1.7%, Ti: 0.50-1.00%, Co: 8.0~20.0%, Fe: 8.0~10.0%, W: 0.80~1.50%, Ni: balance

[0026] It should be noted that the nickel-based high-temperature alloy powder is prepared by uniformly mixing the raw materials in the above-mentioned mass ratio.

[0027] The particle size of the nickel-based high-temperature alloy powder is 15-45 μm.

[0028] In one embodiment, a selective laser melting manufacturing process for a nickel-based high-temperature alloy complex structure blade comprises the following specific steps: (1) Material selection: IN718Plus nickel-based superalloy powder with a particle size range of 15 to 45 µm; wherein the nickel-based superalloy powder includes the following components by mass ratio: Cr 18.9%, Mo 2.8%, W 1.5%, Co 9.3%, Fe9.6%, Nb 5.4%, Ti 0.6%, Al 1.5%, and Ni balance.

[0029] (2) Drying of alloy powder: To prevent moisture from affecting the forming quality of the powder, the powder needs to be dried in a vacuum furnace and heated at 120 °C for 4 h under vacuum. The dried powder is placed in a vacuum bag for later use. (3) Substrate treatment: Use a stainless steel plate as the substrate, remove the oxide scale on the surface of the substrate with sandpaper, and then clean and dry it with acetone; (4) Model segmentation: Construct a 3D model of the complex structure blade to be formed in Materialise Magics software; perform layered processing on the 3D model of the blade; and import the determined parameters of the 3D model into the selective laser melting printer; The layer thickness of the three-dimensional model of the complex structure blade is 0.02 mm.

[0030] Wipe the inside of the selected laser melting equipment with alcohol to make sure it is clean and free of impurities.

[0031] (5) Powder spreading and substrate preheating: Place the alloy powder to be used in a liftable powder supply cylinder; introduce high-purity argon gas as a protective gas into the forming cylinder to make the oxygen content in the cylinder ≤200ppm; place the substrate in the forming cylinder, adjust the position and fix it, and adjust the position of the forming cylinder and the powder supply cylinder respectively so that the upper surface of the substrate in the forming cylinder and the upper edge of the powder in the powder supply cylinder are flush with the lower surface of the equipment scraper; heat the substrate to 100°C to achieve preheating of the substrate; (6) Forming process parameter setting: In the process of printing complex structure blades, the two process instructions mainly used are solid filling process parameters and contour process parameters.

[0032] The solid filling process parameters are as follows: laser power 135 W, laser scanning rate 750 mm / s, layer thickness 0.02 mm, and overlap spacing 0.08 mm.

[0033] The contour process parameters use the single contour method, the contour laser power is 135W, and the laser scanning speed is 750mm / s.

[0034] (7) Laser scanning strategy setting: The scanning strategy for each layer is divided into two parts; ① First, scan the filling part inside the layer, using the reciprocating weaving scanning strategy, that is, reciprocating scanning within the layer; ②After scanning the interior of each layer, perform a single profile laser scan on that layer; After each layer is scanned, the internal scanning direction of the next layer is rotated 67° clockwise based on the scanning direction of the previous layer; The scanning is repeated until all scanning layers are formed. After printing, the parts are separated from the substrate by wire cutting. The complex structure blade of the deposited IN718Plus nickel-based high-temperature alloy is obtained. (8) The specific process of the laser melting forming is: The first layer is selective laser melting and laser forming; Confirm the scanning area, calculate the moving distance of the scraper, and move the scraper to evenly spread the powder in the powder supply cylinder on the substrate to obtain the first layer of alloy powder. The thickness of the first layer of alloy powder is 0.02 mm. Turn on the laser and perform the first scan along the length direction of the part. After the first scan, perform the second scan at an interval of 0.08mm. The second scan direction is opposite to the first scan. Then repeat the first and second scan processes until the internal scan of the layer of the part is completed. Then perform a single scan along the outer contour of the layer of the part at the same power and scanning speed to complete the laser forming of the first layer. The second layer is laser formed; The scraper is moved to evenly spread the powder in the powder supply cylinder on the surface of the formed first laser layer to obtain a second layer of alloy powder; the thickness of the second layer of alloy powder is 0.02 mm; the scanning direction is changed to start the first scan of the second layer, and the scanning direction is the scanning direction of the first scan of the previous layer rotated 67° clockwise; after the first scan of the second layer is completed, the second scan of the second layer is performed at an interval of 0.08 mm, and the scanning direction of the second scan of the second layer is opposite to that of the first scan; then the scanning process of the first scan and the second scan of the layer is repeated until the internal scan of the layer of the part is completed, and then a single scan is performed along the outer contour of the layer of the part at the same power and scanning speed to complete the laser forming of the second layer; The second layer forming process is repeated cyclically until all scanning layers are formed. After printing, the parts are separated from the substrate by wire cutting.

[0035] The scanning of each layer is divided into two parts. After reciprocating scanning inside each layer of the part, a single-pass scan of the outer contour of the part is required to improve the surface forming quality.

[0036] The nickel-based high-temperature alloy complex structure blade prepared by the method of the present invention has no macro cracks and pores, the overall shape of the blade is not distorted, the surface roughness in the deposited state is low, the formability is good, and the density is as high as 99.8%.

[0037] A second aspect of the present invention provides a nickel-based high-temperature alloy complex structure blade manufactured by the above process.

[0038] A third aspect of the present invention provides an application of a nickel-based high-temperature alloy complex structure blade in an aerospace engine.

[0039] It should be noted that the experimental methods used in the present invention are all conventional methods unless otherwise specified; the reagents and materials used are all commercially available unless otherwise specified.

[0040] Example 1 A selective laser melting manufacturing process for a nickel-based high-temperature alloy blade with a complex structure comprises the following steps: (1) Material selection: IN718Plus grade nickel-based high-temperature alloy powder with an average particle size of 25 µm to maintain its powder fluidity and. The nickel-based high-temperature alloy powder includes the following components by mass ratio: Cr 18.9%, Mo 2.8%, W1.5%, Co 9.3%, Fe 9.6%, Nb 5.4%, Ti 0.6%, Al 1.5%, and Ni balance.

[0041] (2) Drying of alloy powder: To prevent moisture from affecting the forming quality, the powder must be dried in a vacuum furnace before printing. The powder is heated at 120 °C for 4 h under vacuum and then placed in a vacuum bag for later use.

[0042] (3) Substrate treatment: Use a stainless steel plate as the substrate, remove the oxide scale on the surface of the substrate with sandpaper, and then clean and dry it with acetone; (4) Model segmentation: Construct a 3D model of the complex structure blade to be formed in the Materialise Magics software; perform layered processing on the 3D model of the blade; and import the determined parameters of the 3D model into the selective laser melting printer.

[0043] (5) The layer thickness of the three-dimensional model of the complex structure blade is 0.02 mm.

[0044] (6) Wipe the inside of the selected laser melting equipment with alcohol to ensure it is clean and free of impurities.

[0045] (7) Powder spreading and substrate preheating: Place the alloy powder to be used in a liftable powder supply cylinder; introduce high-purity argon gas into the forming cylinder as a protective gas and make the oxygen content in the cylinder ≤200ppm; place the substrate in the forming cylinder, adjust the position and fix it, and adjust the position of the forming cylinder and the position of the powder supply cylinder respectively, so that the upper surface of the substrate in the forming cylinder and the upper edge of the powder in the powder supply cylinder are flush with the lower surface of the equipment scraper; heat the substrate to 100°C to achieve preheating of the substrate.

[0046] (6) Forming process parameter setting: In the process of printing complex structure blades, the two process instructions mainly used are solid filling process parameters and contour process parameters.

[0047] The solid filling process parameters include laser power, scanning rate, layer thickness and overlap spacing. The optimized process parameters use a laser power of 135W. The lower laser power can ensure that the high-temperature alloy maintains good material properties without excessive stress causing internal microcracks. The laser scanning rate is 750mm / s. The lower laser scanning speed can increase the laser energy density, avoid the occurrence of unfused phenomena, and improve the material density. The layer thickness is selected as 0.02 mm, and the overlap spacing is selected as 0.08 mm.

[0048] The contour process parameters use a single contour method, the contour laser power is 135W, and the laser scanning speed is 750mm / s. This step can improve the surface quality of the blade and reduce the surface roughness.

[0049] (7) Laser scanning strategy setting: During selective laser melting, the sputtered metal vapor condensate will fall onto a flat metal powder bed along the wind direction. Prioritizing melting and forming the area close to the air outlet can avoid re-melting the metal condensate and causing poor internal fusion of the part.

[0050] The scanning strategy for each layer is divided into two parts: ① First, the inner filling part of the layer is laser scanned, using a reciprocating weaving scanning strategy, that is, reciprocating scanning within the layer; ②After scanning the interior of each layer, perform a single profile laser scan on that layer; In order to reduce the internal thermal stress of the material as much as possible and improve the density of the finished product, after each layer is scanned, the internal scanning direction of the next layer is rotated 67° clockwise based on the scanning direction of the previous layer, so as to minimize the number of overlaps of the scanning melt paths between different layers; The scanning is repeated until all scanning layers are formed, and a complex structure blade of IN718Plus nickel-based high-temperature alloy is obtained; (8) The specific process of the laser melting forming is: The first layer is selective laser melting and laser forming; Confirm the scanning area, calculate the moving distance of the scraper, and move the scraper to evenly spread the powder in the powder supply cylinder on the substrate to obtain the first layer of alloy powder. The thickness of the first layer of alloy powder is 0.02 mm. Turn on the laser and perform the first scan along the length direction of the part. After the first scan, perform the second scan at an interval of 0.08mm. The second scan direction is opposite to the first scan. Then repeat the first and second scan processes until the internal scan of the layer of the part is completed. Then perform a single scan along the outer contour of the layer of the part at the same power and scanning speed to complete the laser forming of the first layer. The second layer is laser formed; The scraper is moved to evenly spread the powder in the powder supply cylinder on the surface of the formed first laser layer to obtain a second layer of alloy powder; the thickness of the second layer of alloy powder is 0.02 mm; the scanning direction is changed to start the first scan of the second layer, and the scanning direction is the scanning direction of the first scan of the previous layer rotated 67° clockwise; after the first scan of the second layer is completed, the second scan of the second layer is performed at an interval of 0.08 mm, and the scanning direction of the second scan of the second layer is opposite to that of the first scan; then the scanning process of the first scan and the second scan of the layer is repeated until the internal scan of the layer of the part is completed, and then a single scan is performed along the outer contour of the layer of the part at the same power and scanning speed to complete the laser forming of the second layer; The second layer forming process is repeated until all scanning layers are formed. After printing, wire cutting is used to separate the parts from the substrate, while taking care to avoid damaging the blade parts.

[0051] In order to illustrate the relevant performance of the blades obtained by the method provided by the present invention, the relevant performance of Example 1 is described in conjunction with the accompanying drawings.

[0052] The macroscopic morphology of the nickel-based high-temperature alloy complex structure blade prepared by the method described in Example 1 is as follows Figure 1 As shown, there are no macro cracks and pores, the overall shape of the blade is not distorted, the surface roughness of the deposited state is low, the formability is good, and the density is as high as 99.8%.

[0053] Figure 2 This is the microstructure diagram of the cross section of the blade in the laser scanning direction of Example 1. Figure 2 (a) is a microscopic morphology of the filling part inside the leaf. It can be found that there are almost no micropores and microcracks inside the leaf tissue. Figure 2 (b) is the morphology of the blade contour part containing a single molten pool. It can be found that the outer surface of the blade has good formability, the contour part structure and the filling part structure are well combined, and there are no macro defects.

[0054] Figure 3 This is the Laves phase morphology of the blade in Example 1. During the selective laser melting process, the laser quickly melts the metal powder and cools it rapidly. The complex thermal process causes the alloy elements such as Nb and Mo to be severely segregated along the interdendritic region and form a granular Laves phase with a size of less than 1 µm.

[0055] Figure 4 (a) and (b) are the diffraction patterns of the blade provided in Example 1 along the laser deposition direction and the scanning direction, respectively. It can be found that due to the influence of the directional heat flow from the laser source to the previous deposition layer, irregular columnar grains with a width of microns are formed inside the blade along the deposition direction, accounting for more than 99% of the entire deposition sample structure.

[0056] The nickel-based high-temperature alloy complex structure blade obtained in this embodiment 1 has a density of up to 99.8%, a tensile strength of 1.10 GPa, and a yield strength of 0.75 GPa.

[0057] Comparative Example 1 The operation steps and scanning strategy of the selective laser melting forming are consistent with those of Example 1, except that: the parameters used in the printing process are: the forming part filling laser input power is 200w, the scanning speed is 800mm / s, the contour laser input power is 120w, and the scanning speed is 900mm / s; the density of the obtained product is only 98.37%, and the tensile strength is only 985MPa.

[0058] The present invention describes preferred embodiments and their effects. However, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0059] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A selective laser melting manufacturing process for complex structure blades of nickel-based high-temperature alloy, characterized in that: The following steps are involved: Formulating nickel-based high-temperature alloy powder; Construct a three-dimensional model of a blade with a complex structure to be formed, perform layered processing on the blade three-dimensional model, and import various parameters of the three-dimensional model into the selective laser melting equipment; Place nickel-based high-temperature alloy powder in a liftable powder supply cylinder, and adjust the positions of the forming cylinder and the powder supply cylinder respectively, so that the upper surface of the substrate in the forming cylinder and the upper edge of the powder in the powder supply cylinder are flush with the lower surface of the equipment scraper; Argon gas is introduced into the molding cylinder as a protective gas, and the substrate is preheated; Set filling process parameters and contour process parameters; Laser melting is performed by laser scanning, wherein the laser scanning method includes: first scanning the internal filling part of each layer, and then performing a single contour laser scan on the layer; By cyclic scanning until all scanning layers are formed, a nickel-based high-temperature alloy blade with a complex structure is obtained.

2. The selective laser melting manufacturing process for complex structured nickel-based high-temperature alloy blades according to claim 1 is characterized in that: The filling process parameters were laser power 135 W, laser scanning rate 750 mm / s, layer thickness 0.02 mm, and overlap spacing 0.08 mm; The contour process parameters use the single contour method, the contour laser power is 135W, and the laser scanning speed is 750mm / s.

3. The selective laser melting manufacturing process for complex structured nickel-based high-temperature alloy blades according to claim 1 is characterized in that: After each layer is scanned, the internal scanning direction of the next layer is rotated 67° clockwise based on the scanning direction of the previous layer.

4. The selective laser melting manufacturing process for nickel-based high-temperature alloy complex structure blades according to claim 1 is characterized in that: The laser melting process includes: First layer selective laser melting laser forming: Confirm the scanning area, calculate the moving distance of the scraper, and move the scraper to evenly spread the powder in the powder supply cylinder on the substrate to obtain the first layer of alloy powder; Turn on the laser and perform the first scan along the length direction of the part. After the first scan, perform the second scan at an interval of 0.08mm. The second scan direction is opposite to the first scan. Then repeat the first and second scan processes until the internal scan of the layer of the part is completed. Then perform a single scan along the outer contour of the layer of the part at the same power and scanning speed to complete the laser forming of the first layer. Second layer laser forming: The scraper is moved to evenly spread the powder in the powder supply cylinder on the surface of the first laser forming layer to obtain the second layer of alloy powder. The scanning direction is changed to start the first scan of the second layer. After the first scan of the second layer is completed, the second scan of the second layer is performed at an interval of 0.08mm. The scanning direction of the second scan of the second layer is opposite to that of the first scan. Then, the scanning process of the first and second scans of the layer is repeated until the internal scan of the layer of the part is completed. Then, a single scan is performed along the outer contour of the layer of the part at the same power and scanning speed to complete the laser forming of the second layer. The process of forming the second layer is cyclically repeated until the forming of all scanning layers is completed.

5. The selective laser melting manufacturing process for nickel-based high-temperature alloy complex structure blades according to claim 4 is characterized in that: The thickness of the first alloy powder layer is 0.02 mm; the thickness of the second alloy powder layer is 0.02 mm.

6. The selective laser melting manufacturing process for nickel-based high-temperature alloy complex structure blades according to claim 1 is characterized in that: When scanning the inner filling part of each layer, reciprocating weaving is used for scanning.

7. The selective laser melting manufacturing process for nickel-based high-temperature alloy complex structure blades according to claim 1 is characterized in that: The nickel-based high-temperature alloy raw material includes the following components by mass ratio: Cr: 17.0-21.0%, Mo: 2.50-3.10%, Nb: 5.20-5.80%, Al: 1.2-1.7%, Ti: 0.50-1.00%, Co: 8.0-20.0%, Fe: 8.0-10.0%, W: 0.80-1.50%, and Ni: balance.

8. The selective laser melting manufacturing process for nickel-based high-temperature alloy complex structure blades according to claim 1 is characterized in that: The particle size of the nickel-based high-temperature alloy powder is 15-45 μm.

9. A nickel-based high-temperature alloy complex structure blade made by the process described in any one of claims 1 to 8.

10. Use of the nickel-based high-temperature alloy complex structure blade according to claim 9 in an aerospace engine.

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