A method and apparatus for controlling a laser additive manufacturing process

Abstract

The application provides a laser additive manufacturing process control method and device, and the laser additive manufacturing process control method first establishes a process calling library, divides a to-be-printed part along a first direction according to a threshold value of a thin-wall feature and the size of a cross section of the to-be-printed part, obtains a plurality of area blocks, divides the area blocks into a plurality of sub-blocks according to the size of a first included angle, then determines the powder layer thickness of each sub-block, and determines the spot size and process parameters corresponding to a sub-block according to the powder layer thickness and the process calling library. The application improves the precision and efficiency of laser additive manufacturing.

Description

Technical Field

[0001] This invention relates to the field of laser additive manufacturing technology, and in particular to a laser additive manufacturing process control method and apparatus. Background Technology

[0002] Laser additive manufacturing is a novel layer-by-layer processing technology that uses high-energy lasers to melt materials such as metals and then deposit them layer by layer to create parts. Traditional laser additive manufacturing processes, when printing metal parts, use a single-mode laser (such as a Gaussian laser) and a fixed combination of process parameters (such as powder layer thickness, laser power, scanning speed, and scanning spacing) to melt and solidify layer by layer the solid slice file of the 3D part, ultimately forming a blank solid of the 3D part. Traditional laser additive manufacturing processes have relatively low efficiency and accuracy. Summary of the Invention

[0003] This invention provides a method and apparatus for controlling laser additive manufacturing processes, thereby improving the efficiency and precision of laser additive manufacturing processes.

[0004] According to one aspect of the present invention, a laser additive manufacturing process control method is provided. The laser additive manufacturing process control method includes: acquiring a process call library, wherein the process call library includes spot sizes and process parameters corresponding to different powder layer thicknesses; at least partially different powder layer thicknesses correspond to different spot sizes, and at least partially different powder layer thicknesses correspond to different process parameters; dividing the part to be printed along a first direction according to a threshold of thin-wall features and the size of the cross-section of the part to be printed, to obtain multiple region blocks, wherein the first direction is perpendicular to the cross-section, adjacent region blocks correspond to different cross-sectional sizes, and adjacent region blocks correspond to different reference powder layer thicknesses; dividing each region block according to a first angle between the tangent of the outer contour of the region block and the cross-section of the region block, to obtain multiple sub-blocks, wherein adjacent sub-blocks have different first angles; determining the powder layer thickness of the sub-block according to the first angle of the sub-block and the reference powder layer thickness of the region block in which the sub-block is located; and determining the spot size and process parameters corresponding to each sub-block according to the powder layer thickness of each sub-block and the process call library.

[0005] Optionally, the process parameters include laser power and scanning speed; the range of spot size corresponding to different powder layer thickness ranges is different, the range of laser power corresponding to different powder layer thickness ranges is different, and the range of scanning speed corresponding to different powder layer thickness ranges is different.

[0006] Optionally, the region block includes at least one first region block and at least one second region block, wherein the reference powder layer thickness of the first region block is greater than the reference powder layer thickness of the second region block.

[0007] The cross-sectional dimension of the first region block is greater than the threshold of the thin-walled feature.

[0008] The cross-sectional dimension of the second region block is less than or equal to the threshold of the thin-walled feature.

[0009] Optionally, the threshold of the thin-walled feature is less than or equal to 2 mm.

[0010] Optionally, the first included angle of the same sub-block is within the same angular range.

[0011] Optionally, determining the powder layer thickness of the sub-block based on the first included angle of the sub-block and the reference powder layer thickness of the region block in which the sub-block is located includes: determining the powder layer thickness of the sub-block based on the minimum value of the first included angle of the sub-block and the reference powder layer thickness of the region block in which the sub-block is located.

[0012] Optionally, the reference powder layer thickness of the first region block is 60 μm, and the reference powder layer thickness of the second region block is 20 μm.

[0013] Optionally, the powder layer thickness of the sub-block is determined according to the following formula: L=μ×Sinθ min .

[0014] Where L is the powder layer thickness of the sub-block, μ is the reference powder layer thickness corresponding to the region block where the sub-block is located, and θ min It is the minimum value of the first included angle of the sub-block.

[0015] Optionally, the laser additive manufacturing process control method further includes: slicing each sub-block according to the powder layer thickness of the sub-block to form a printing file; loading the printing file, the spot size corresponding to the sub-block, and the process parameters into the printing system for printing.

[0016] According to another aspect of the present invention, a laser additive manufacturing process control device is provided. The laser additive manufacturing process control device includes: a process call library acquisition module, configured to acquire a process call library, wherein the process call library includes spot sizes and process parameters corresponding to different powder layer thicknesses; at least partially different powder layer thicknesses correspond to different spot sizes, and at least partially different powder layer thicknesses correspond to different process parameters; and a region block formation module, configured to partition the part to be printed along a first direction according to a threshold of thin-wall features and the dimensions of the cross-section of the part to be printed, obtaining multiple region blocks, wherein the first direction is perpendicular to the cross-section, and adjacent regions are... The dimensions of the cross sections corresponding to the aforementioned region blocks are different, and the reference powder layer thicknesses corresponding to adjacent region blocks are different; the sub-block forming module is used to divide each region block into multiple sub-blocks according to the first included angle between the tangent of the outer contour of the region block and the cross section of the region block, wherein the first included angle of adjacent sub-blocks is different; the sub-block powder layer thickness determining module is used to determine the powder layer thickness of the sub-block according to the first included angle of the sub-block and the reference powder layer thickness of the region block in which the sub-block is located; the spot size and process parameter determining module is used to determine the spot size and process parameters corresponding to each sub-block according to the powder layer thickness of each sub-block and the process call library.

[0017] The laser additive manufacturing process control method provided in this embodiment first establishes a process call library. Based on the threshold of thin-wall features and the cross-sectional dimensions of the part to be printed, the part is divided into multiple regions along a first direction. Different reference powder layer thicknesses are used for regions with different cross-sectional dimensions. Then, the regions are divided into multiple sub-blocks based on the size of the first included angle of their contours. The powder layer thickness of each sub-block is determined based on its first included angle and the reference powder layer of the region it belongs to. Finally, the spot size and process parameters corresponding to each sub-block are determined based on the powder layer thickness and the process call library. This embodiment achieves the determination of powder layer thickness for sub-blocks with different cross-sectional dimensions and different contour angles, and at least some different powder layer thicknesses correspond to different spot sizes and process parameters. This ensures that the spot size, process parameters, and powder layer thickness are all adapted to the morphology of the sub-blocks, improving the accuracy and efficiency of laser additive manufacturing.

[0018] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of a laser additive manufacturing process control method provided in an embodiment of the present invention.

[0021] Figure 2 These are cross-sectional comparison images of a single melt channel formed by laser selective melting of titanium alloy under different process parameters.

[0022] Figure 3 This is a schematic diagram of the model of the part to be printed provided in an embodiment of the present invention.

[0023] Figure 4 This is a schematic diagram showing the formation of multiple region blocks.

[0024] Figure 5 This is a diagram illustrating how region block X1 is divided into two sub-blocks.

[0025] Figure 6 This is a schematic diagram of the laser additive manufacturing process in the existing technology.

[0026] Figure 7 This is a schematic diagram of the powder layer thickness in region block X2 and region block X3.

[0027] Figure 8 This is a schematic diagram of a laser additive manufacturing process control device provided in an embodiment of the present invention. Detailed Implementation

[0028] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of 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 skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0029] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0030] This invention provides a method for controlling the laser additive manufacturing process. Figure 1 This is a schematic flowchart of a laser additive manufacturing process control method provided in an embodiment of the present invention, with reference to... Figure 1 A laser additive manufacturing process control method includes: S101. Obtain the process call library, wherein the process call library includes spot size and process parameters corresponding to different powder layer thicknesses; at least some different powder layer thicknesses correspond to different spot sizes, and at least some different powder layer thicknesses correspond to different process parameters.

[0031] Specifically, by identifying the melting channel characteristics of the laser energy acting on the powder layer, a process call library is established. The process call library includes the spot size and process parameters corresponding to different powder layer thicknesses. The powder layer thickness refers to the thickness of each layer of metal or non-metal powder laid on the processing platform by the powder spreading device. The spot size includes the spot diameter, and the process parameters include laser power, scanning speed, and scanning spacing. Figure 2 These are cross-sectional comparison images of individual melt channels formed by laser selective melting of titanium alloys under different process parameters. Figure 2 By comparing the cross-sectional diagrams of individual melt channels, under the same powder layer thickness, process parameters that can ensure better forming quality in laser additive manufacturing can be selected, and process parameters corresponding to unqualified melt channels can be eliminated, thereby forming a process call library. Figure 2 The melt flow lines highlighted in the red box are defective. Figure 2 The values ​​on the right side of the image, such as 180W, represent the laser power, and the values ​​at the bottom of the image, such as 800mm / s, represent the scanning speed. Table 1 shows the spot size and process parameters corresponding to different powder layer thicknesses in the process call library. S102. Based on the threshold of the thin-wall feature and the size of the cross-section of the part to be printed, the part to be printed is divided into multiple regions along the first direction to obtain multiple region blocks. The first direction is perpendicular to the cross-section, and the cross-sections of adjacent region blocks are different in size and the reference powder layer thicknesses of adjacent region blocks are different.

[0032] Specifically, the cross-sectional dimension of the part to be printed is the minimum dimension of the cross-section of the part to be printed in the XY plane. For example, when the part to be printed is a solid structure, the cross-sectional dimension is the minimum dimension of the cross-sectional profile of the solid structure in the XY plane; when the part to be printed is a ring-shaped hollow structure, the cross-sectional dimension is the minimum wall thickness of the ring-shaped structure. Adjacent regions may have different cross-sectional dimensions, which could be due to the cross-sectional dimensions of adjacent regions falling within different size ranges. For instance, a threshold for thin-walled features can be set, where one adjacent region has a cross-sectional dimension greater than the threshold, and the other has a dimension less than the threshold. Alternatively, two or more different thresholds for thin-walled features can be set, dividing the area into multiple different size ranges based on these thresholds. Regions with cross-sectional dimensions within the same size range are grouped into the same region, while regions with cross-sectional dimensions within different size ranges are grouped into different regions. Setting different base powder layer thicknesses for adjacent regions can satisfy the powder layer thickness requirements of different cross-sectional sizes. For example, regions with larger cross-sectional sizes correspond to larger powder layer thicknesses, and regions with smaller cross-sectional sizes correspond to smaller powder layer thicknesses.

[0033] For example, Figure 3 This is a schematic diagram of the model of the part to be printed provided in an embodiment of the present invention, with reference to... Figure 3 , Figure 3 The left image is a front view of the part to be printed, and the right image is a top view. The cross-section of the part to be printed is parallel to the XY plane. The placement direction of the part to be printed is determined by the three-dimensional solid model of the part. The first direction is the placement direction of the part to be printed, which is perpendicular to the cross-section and can be the Z direction. Based on the threshold of the thin-wall feature and the dimensions of the cross-section of the part to be printed, the part to be printed is cut along the first direction Z to form multiple region blocks. For example, Figure 4 For a schematic diagram showing the formation of multiple region blocks, refer to... Figure 3 and Figure 4 ,Will Figure 3 The parts to be printed are divided into three regions, namely X1, X2 and X3, based on the threshold of thin-wall features and the size of the cross-section of the parts to be printed.

[0034] S103. Based on the first angle between the tangent of the outer contour of the region block and the cross section of the region block, divide each region block into multiple sub-blocks, wherein the first angle between adjacent sub-blocks is different.

[0035] Specifically, multiple sub-blocks can be arranged sequentially along the first direction. The cross-section of the region block is parallel to the XY plane. Figure 5 This is a diagram illustrating the division of region block X1 into two sub-blocks. (Refer to...) Figure 5 Based on the different first angles between the tangent of the outer contour of region block X1 and the cross-section of the region block, region block X1 is divided into sub-blocks K1 and K2. The tangent of the outer contour of region block X1 is as follows: Figure 5 As shown by the red and black dashed lines. The first angle between sub-block K1 and its cross-section is 90°, and the first angle between sub-block K2 and its cross-section is θ0. The first angle between the outer contour of region block X2 and its cross-section is 90°, and the first angle between the outer contour of region block X3 and its cross-section is 90°.

[0036] S104. Determine the powder layer thickness of the sub-block based on the first included angle of the sub-block and the reference powder layer thickness of the area block where the sub-block is located.

[0037] Specifically, the smaller the first included angle of the sub-block, the smaller the powder layer thickness of the sub-block. The powder layer thickness of the sub-block can be determined by multiplying the sine value of the first included angle of the sub-block with the reference powder layer thickness of the block in which the sub-block is located.

[0038] S105. Determine the spot size and process parameters corresponding to each sub-block based on the powder layer thickness of each sub-block and the process call library.

[0039] Specifically, the spot size, laser power, and scanning speed for each sub-block are determined in Table 1 based on the powder layer thickness of each sub-block.

[0040] Figure 6 This is a schematic diagram of the existing laser additive manufacturing process, for reference. Figure 6 In existing technologies, the digital file of a 3D entity is first layered according to a specific layer thickness. For each layer of the digital file, path planning is performed to obtain the laser scanning path information for each layer of the 2D digital file. Following the set 2D path information and the scanning sequence initiated by the equipment control system, the melting and accumulation of the melt channels are completed layer by layer. After each layer is melted, the printing platform descends by one layer thickness, and another layer of powder is laid. The laser continues to melt layer by layer according to the path in the 2D digital file. Layer-by-layer printing completes the accumulation and manufacturing of the part entity. Existing technologies use fixed layer thicknesses and fixed lasers for layered printing of the part to be printed, resulting in low printing accuracy.

[0041] The laser additive manufacturing process control method provided in this embodiment first establishes a process call library. Based on the threshold of thin-wall features and the cross-sectional dimensions of the part to be printed, the part is divided into multiple regions along a first direction. Different reference powder layer thicknesses are used for regions with different cross-sectional dimensions. Then, the regions are divided into multiple sub-blocks based on the size of the first included angle of their contours. The powder layer thickness of each sub-block is determined based on its first included angle and the reference powder layer of the region it belongs to. Finally, the spot size and process parameters corresponding to each sub-block are determined based on the powder layer thickness and the process call library. This embodiment achieves the determination of powder layer thickness for sub-blocks with different cross-sectional dimensions and different contour angles, and at least some different powder layer thicknesses correspond to different spot sizes and process parameters. This ensures that the spot size, process parameters, and powder layer thickness are all adapted to the morphology of the sub-blocks, improving the accuracy and efficiency of laser additive manufacturing.

[0042] Optional process parameters include laser power and scanning speed; different spot size ranges correspond to different powder layer thickness ranges, different laser power ranges correspond to different powder layer thickness ranges, and different scanning speed ranges correspond to different powder layer thickness ranges.

[0043] Specifically, the spot size includes the spot diameter. Using a larger spot diameter, higher laser power, and higher scanning speed for sub-blocks with larger powder layer thickness can achieve the formation of larger melt channels and improve the efficiency of laser additive manufacturing. Using a smaller spot diameter, lower laser power, and lower scanning speed for sub-blocks with smaller powder layer thickness can achieve the delineation of fine structures and improve the precision of laser additive manufacturing.

[0044] Optionally, the region block includes at least one first region block and at least one second region block, wherein the reference powder layer thickness of the first region block is greater than the reference powder layer thickness of the second region block.

[0045] The cross-sectional size of the first region block is greater than the threshold of the thin-walled feature.

[0046] The cross-sectional dimensions of the second region block are less than or equal to the threshold of the thin-walled feature.

[0047] Specifically, if the cross-sectional size of the first region block is greater than the threshold for thin-walled features, it indicates that the first region block does not have thin-walled features; if the cross-sectional size of the second region block is less than or equal to the threshold for thin-walled features, it indicates that the second region block has thin-walled features. Therefore, the reference powder layer thickness of the first region block is set to be greater than the reference powder layer thickness of the second region block. By setting a larger reference powder layer thickness for the first region block (which does not have thin-walled features), the powder layer thickness of the sub-blocks is made larger; conversely, by setting a smaller reference powder layer thickness for the second region block (which has thin-walled features), the powder layer thickness of the sub-blocks is made smaller. This improves the efficiency and accuracy of laser additive manufacturing.

[0048] Optionally, the threshold for thin-walled features is less than or equal to 2 mm.

[0049] Specifically, an excessively high threshold for thin-walled features can lead to inaccurate partitioning of the parts to be printed, thus reducing the accuracy of laser additive manufacturing. Setting the threshold for thin-walled features to be less than or equal to 2 mm can improve the accuracy of laser additive manufacturing. For example, the threshold for thin-walled features can be 1.5 mm, 1.6 mm, 1.8 mm, or 2 mm, etc.

[0050] Optionally, the first included angle θ of the same sub-block lies within the same angular range.

[0051] Specifically, based on the size of the first angle between the tangent of the outer contour of the region block and the cross-section of the region block, each region block is divided into multiple sub-blocks according to different angle ranges. The first angle θ of the same sub-block lies within the same angle range. For example, regions θ1≤θ≤θ2 are the same sub-block, regions θ2<θ≤θ3 are the same sub-block, regions θ3<θ≤θ4 are the same sub-block, and so on. n-1 <θ≤θ n The regions are the same sub-block, θ n Less than or equal to 180°.

[0052] Optionally, determining the powder layer thickness of the sub-block based on the first included angle of the sub-block and the reference powder layer thickness of the region block in which the sub-block is located includes: determining the powder layer thickness of the sub-block based on the minimum value of the first included angle of the sub-block and the reference powder layer thickness of the region block in which the sub-block is located.

[0053] Specifically, when the outer contour of the same sub-block is a curve or a broken line, the first included angle of the sub-block is not a fixed value. The first included angle of the sub-block is within a certain angle range. The minimum value of the first included angle and the reference powder layer thickness of the area block where the sub-block is located are used to determine the powder layer thickness of the sub-block. This makes the powder layer thickness used in the sub-block smaller, which can improve the accuracy of laser additive manufacturing.

[0054] Optionally, the reference powder layer thickness of the first region block is 60 μm, and the reference powder layer thickness of the second region block is 20 μm.

[0055] Specifically, the reference powder layer thickness for the first region is set to 60 μm, resulting in a larger powder layer thickness for the sub-blocks within the first region. This allows for the use of larger spot sizes and process parameters, thereby improving the efficiency of laser additive manufacturing. Conversely, the reference powder layer thickness for the second region is set to 20 μm, resulting in a smaller powder layer thickness for the sub-blocks within the second region. This allows for the use of smaller spot sizes and process parameters, thereby improving the precision of laser additive manufacturing. (Reference) Figure 3 and Figure 4Region blocks X1 and X3 are both first region blocks, and region block X2 is the second region block. Therefore, the reference powder layer thickness of region blocks X1 and X3 is set to 60 μm, and the reference powder layer thickness of region block X2 is set to 20 μm.

[0056] Optionally, the powder layer thickness of the sub-block is determined according to the following formula: L=μ×Sinθ min .

[0057] Where L is the powder layer thickness of the sub-block, μ is the reference powder layer thickness corresponding to the region block where the sub-block is located, and θ min It is the minimum value of the first included angle of the sub-block.

[0058] Specifically, Figure 7 This is a schematic diagram showing the powder layer thickness in region X2 and region X3, for reference. Figure 5 and Figure 7 The reference powder layer thickness of regions X1 and X3 is 60 μm, the reference powder layer thickness of region X2 is 20 μm, and the first included angle of sub-block K1 in region X1 is... The minimum value is 90°, and the powder layer thickness L of sub-block K1 is 60×sin90°=60μm; the minimum value of the first included angle θ of sub-block K2 in region block X1 is θ. min The powder layer thickness L of sub-block K2 is 60×sinθ0, which equals θ0. The minimum value of the first included angle θ of sub-block K3 in region block X2 is 90°, and the powder layer thickness L of sub-block K1 is 20×sin90°=20μm. The minimum value of the first included angle θ of sub-block K4 in region block X3 is 90°, and the powder layer thickness L of sub-block K1 is 60×sin90°=60μm.

[0059] Optionally, the laser additive manufacturing process control method also includes: slicing each sub-block according to the powder layer thickness of the sub-block to form a printing file; loading the printing file and the spot size and process parameters corresponding to the sub-block into the printing system for printing.

[0060] Specifically, each sub-block is sliced ​​according to its corresponding powder layer thickness, resulting in a slice file for each sub-block. A printing path, corresponding spot size, and process parameters are assigned to each layer's printing file. These files are then imported into the printing system. During the printing process of each layer, the printing system descends by the required distance based on the powder layer thickness of each sub-block. The doctor blade mechanism in the printing system spreads the powder. A spot diffractometer is used to obtain the spot size corresponding to the powder layer thickness of the sub-block to be printed. Under the control of the laser control card, the laser outputs according to the set path and process parameters, repeating the printing steps until the part is printed.

[0061] This invention provides a laser additive manufacturing process control device. Figure 8 This is a schematic diagram of a laser additive manufacturing process control device provided in an embodiment of the present invention, with reference to... Figure 8 The laser additive manufacturing process control device includes: The process call library acquisition module 301 is used to acquire the process call library, wherein the process call library includes spot size and process parameters corresponding to different powder layer thicknesses; at least some different powder layer thicknesses correspond to different spot sizes, and at least some different powder layer thicknesses correspond to different process parameters; The region block forming module 302 is used to divide the part to be printed along the first direction according to the threshold of the thin-wall feature and the size of the cross section of the part to be printed, to obtain multiple region blocks, wherein the first direction is perpendicular to the cross section, the cross section sizes of adjacent region blocks are different, and the reference powder layer thicknesses of adjacent region blocks are different. The sub-block forming module 303 is used to divide each region block into multiple sub-blocks based on the first angle between the tangent of the outer contour of the region block and the cross section of the region block, wherein the first angle of adjacent sub-blocks is different. The sub-block powder layer thickness determination module 304 is used to determine the powder layer thickness of the sub-block based on the first included angle of the sub-block and the reference powder layer thickness of the region block where the sub-block is located. The spot size and process parameter determination module 305 is used to determine the spot size and process parameters corresponding to each sub-block based on the powder layer thickness of each sub-block and the process call library.

[0062] This invention, through the cooperation of various modules, establishes a process call library. Based on the threshold of thin-wall characteristics and the cross-sectional dimensions of the part to be printed, the part is divided into multiple regions along a first direction. Different reference powder layer thicknesses are applied to regions with different cross-sectional dimensions. The regions are then divided into multiple sub-blocks based on the size of the first included angle of their contours. The powder layer thickness of each sub-block is determined based on its first included angle and the reference powder layer of the region it belongs to. Finally, the spot size and process parameters corresponding to each sub-block are determined based on the powder layer thickness and the process call library. This embodiment enables the determination of powder layer thickness for sub-blocks with different cross-sectional dimensions and contour angles, and at least some different powder layer thicknesses correspond to different spot sizes and process parameters. This ensures that the spot size, process parameters, and powder layer thickness are all adapted to the morphology of the sub-blocks, improving the accuracy and efficiency of laser additive manufacturing.

[0063] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0064] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for controlling a laser additive manufacturing process, characterized in that, include: Obtain a process call library, wherein the process call library includes spot sizes and process parameters corresponding to different powder layer thicknesses; at least some of the different powder layer thicknesses correspond to different spot sizes, and at least some of the different powder layer thicknesses correspond to different process parameters; The part to be printed is divided into multiple regions along a first direction based on the threshold of thin-wall characteristics and the size of the cross-section of the part to be printed. The first direction is perpendicular to the cross-section, and the cross-sections of adjacent regions have different sizes and the reference powder layer thicknesses of adjacent regions are different. Based on the first angle between the tangent of the outer contour of the region block and the cross section of the region block, each region block is divided into multiple sub-blocks, wherein the first angle of adjacent sub-blocks is different. The powder layer thickness of the sub-block is determined based on the first included angle of the sub-block and the reference powder layer thickness of the region block in which the sub-block is located; The spot size and process parameters corresponding to each sub-block are determined based on the powder layer thickness of each sub-block and the process call library.

2. The laser additive manufacturing process control method according to claim 1, characterized in that: The process parameters include laser power and scanning speed; Different powder layer thicknesses correspond to different spot size ranges, different powder layer thicknesses correspond to different laser power ranges, and different powder layer thicknesses correspond to different scanning speed ranges.

3. The laser additive manufacturing process control method according to claim 1, characterized in that: The region block includes at least one first region block and at least one second region block, wherein the reference powder layer thickness of the first region block is greater than the reference powder layer thickness of the second region block; The cross-sectional dimension of the first region block is greater than the threshold of the thin-walled feature; The cross-sectional dimension of the second region block is less than or equal to the threshold of the thin-walled feature.

4. The laser additive manufacturing process control method according to claim 1, characterized in that: The threshold for the thin-walled feature is less than or equal to 2 mm.

5. The laser additive manufacturing process control method according to claim 1, characterized in that: The first included angle of the same sub-block is within the same angular range.

6. The laser additive manufacturing process control method according to claim 1, characterized in that, Based on the first included angle of the sub-block and the reference powder layer thickness of the region block where the sub-block is located, the powder layer thickness of the sub-block is determined as follows: The powder layer thickness of the sub-block is determined based on the minimum value of the first included angle of the sub-block and the reference powder layer thickness of the region block in which the sub-block is located.

7. The laser additive manufacturing process control method according to claim 3, characterized in that: The reference powder layer thickness of the first region block is 60 μm, and the reference powder layer thickness of the second region block is 20 μm.

8. The laser additive manufacturing process control method according to claim 6, characterized in that: The powder layer thickness of the sub-block is determined according to the following formula: L=μ×Sinθ min ; Where L is the powder layer thickness of the sub-block, μ is the reference powder layer thickness corresponding to the region block where the sub-block is located, and θ min It is the minimum value of the first included angle of the sub-block.

9. The laser additive manufacturing process control method according to claim 1, characterized in that, Also includes: Each sub-block is sliced ​​according to the thickness of the powder layer of the sub-block to form a print file; The print file, the spot size corresponding to the sub-block, and the process parameters are loaded into the printing system for printing.

10. A laser additive manufacturing process control device, characterized in that, include: A process call library acquisition module is used to acquire a process call library, wherein the process call library includes spot sizes and process parameters corresponding to different powder layer thicknesses; at least some of the different powder layer thicknesses correspond to different spot sizes, and at least some of the different powder layer thicknesses correspond to different process parameters; A region block forming module is used to divide the part to be printed along a first direction according to the threshold of thin-wall features and the size of the cross-section of the part to be printed, to obtain multiple region blocks, wherein the first direction is perpendicular to the cross-section, adjacent region blocks have different cross-sectional sizes, and adjacent region blocks have different reference powder layer thicknesses. A sub-block forming module is used to divide each region block into multiple sub-blocks based on the first angle between the tangent of the outer contour of the region block and the cross section of the region block, wherein the first angle of adjacent sub-blocks is different. The sub-block powder layer thickness determination module is used to determine the powder layer thickness of the sub-block based on the first included angle of the sub-block and the reference powder layer thickness of the region block where the sub-block is located; The spot size and process parameter determination module is used to determine the spot size and process parameters corresponding to each sub-block based on the powder layer thickness of each sub-block and the process call library.

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