A laser additive manufacturing method for thin-walled three-period minimal curved surface lattice structures

Abstract

This invention discloses a laser additive manufacturing method for a thin-walled three-period minimal surface lattice structure, relating to the field of additive manufacturing, comprising the following steps: (1) obtaining single-path contours for each layer by direct slicing based on the implicit function of the three-period minimal surface and the thickness of the additive manufacturing layer; (2) generating parallel filling lines in each layer and intersecting them with the combination of the contour paths of that layer and the layer above; (3) combining the obtained intersection points in pairs to form line segments, and using the line segment sampling points as filling paths if they satisfy the functional expression, tilt angle, and length conditions; (4) using the filling path of that layer as a support layer and moving it up one layer to form a filling layer; (5) inputting all the above paths into an additive manufacturing equipment and setting different processing parameters for manufacturing. This invention can efficiently generate laser paths for thin-walled three-period minimal surface lattice structures, with only one melt channel in the thickness direction of the structure, a wall thickness of less than 200 micrometers, and can fill voids and defects generated during the slicing process.

Description

Technical Field

[0001] This invention relates to the field of additive manufacturing, and more particularly to a laser additive manufacturing method for a thin-walled, three-period minimal curved surface lattice structure. Background Technology

[0002] Additive manufacturing is a crucial field in advanced manufacturing. Its "layer-by-layer manufacturing" method liberates the freedom of part manufacturing and has unique advantages in shaping complex geometric models, enabling the creation of structures that are difficult to form using traditional manufacturing processes. In the implementation of additive manufacturing technology, slicing the model to form the tool head path is one of the important steps in additive manufacturing data preprocessing.

[0003] Tri-period minimal surfaces, characterized by continuity, smoothness, and large specific surface area, are often used as lattice structures to fill the interior of parts, enabling them to achieve excellent properties such as lightweight, high strength, and good heat dissipation. In the industrial field, their large specific surface area has led to their increasingly widespread application in parts such as heat exchangers. Furthermore, the development of additive manufacturing has made it possible to create this complex structural model.

[0004] The common method for generating slicing paths in additive manufacturing is to export the 3D model of the part into STL format, and then use specialized slicing software to convert it into a printing task file containing path, parameter and other information. However, this approach has certain limitations: Additive manufacturing demonstrates its advantages in manufacturing complex parts. For complex lattice structures such as three-period minimal curved surfaces, they often share the characteristics of complex internal structure and large specific surface area. The number of triangular facets in the STL file is positively correlated with the surface area of ​​the part, resulting in a large number of triangular facets that need to be stored in the STL file of complex parts. The part geometry design and path generation process require extremely high processing time and memory usage. In addition, the slicing of STL models often results in a closed contour surrounding the part, making it difficult to form a single-pass scanning path for open curved surfaces, which limits the minimum wall thickness of micro-scale thin-walled parts formed by additive manufacturing.

[0005] Research indicates that existing studies primarily utilize direct slicing techniques to avoid the accuracy, efficiency, and memory bottlenecks associated with STL models in slicing complex parts. These techniques include explicit modeling direct slicing (such as CAD direct slicing and point cloud direct slicing), as well as discrete data direct slicing and implicit function direct slicing. Tri-period minimal surfaces can be directly represented by implicit function analytical expressions, and implicit function direct slicing can effectively improve slicing efficiency. Existing research has extensively studied implicit function direct slicing of tri-period minimal surfaces, but it still has the following limitations: 1. Existing research generally uses variant F... 2 =C 2(where F is the implicit function of the three-period minimal surface and C is a constant controlling the wall thickness of the model) to generate a three-period minimal surface model with a certain wall thickness, and scan the solid region. However, the wall thickness of the structure processed by this method exceeds the width of the double-track molten pool and fails to reach the processing limit of the single-track molten pool width; 2. For the existing single-track scanning research of the three-period minimal surface, when the unit cell size exceeds 5mm, hole defects will appear, which seriously affect the quality and performance of the parts.

[0006] Therefore, those skilled in the art are dedicated to developing a laser additive manufacturing method for thin-walled, three-period minimal curved surface lattice structures. Summary of the Invention

[0007] In view of the above-mentioned defects of the prior art, the technical problem to be solved by the present invention is that the three-cycle minimal curved surface lattice structure model currently used for additive manufacturing fails to reach the processing limit of single-pass melt pool width, the slicing method has high memory consumption and time consumption, low processing efficiency, and the model unit cell size exceeds 5mm and hole defects appear.

[0008] To achieve the above objectives, the present invention provides a laser additive manufacturing method for a thin-walled, three-period minimal curved surface lattice structure, the method comprising the following steps:

[0009] Step 1: Based on the implicit function model expression F(x,y,z)=0 of the three-period minimum surface and the layer thickness adapted to the laser selective melting additive manufacturing equipment, the single-pass contour path of each layer is obtained by direct slicing.

[0010] Step 2: Traverse each plane layer, generate a series of parallel fill lines according to the set fill line spacing value, and find the intersection of the parallel fill lines with the contour path of the current layer and the contour path of the next higher layer.

[0011] Step 3: The resulting intersection points are combined in pairs to form line segments. Sampling points are taken in each line segment. If the function and tilt angle requirements are met at the same time and the line segment length is greater than the set threshold, the line segment is retained as the filling path.

[0012] Step 4: Use the filling path of this layer as a support layer, and move it up one layer to form a filling layer. Set different process parameters for the support layer and the filling layer to optimize the filling effect.

[0013] Step 5: Generate a path file that the additive manufacturing equipment can recognize based on the contour path and the filling path, input it into the additive manufacturing equipment, set the processing parameters, and carry out manufacturing.

[0014] Further, the specific process of step 1 is as follows: based on the layer thickness information, the planes perpendicular to the z-axis at each height of the model are traversed to obtain the contour lines of the implicit function model F(x,y,z)=0 in each plane, which are used as single-track contour scanning paths. This process is called direct slicing.

[0015] In step 1, the three-period minimum surface is a Gyroid surface, a Primitive surface, or a Diamond surface. The implicit function expression of the Gyroid surface is F(x,y,z)=sin(2πx / L)·cos(2πy / L)+sin(2πy / L)·cos(2πz / L)+sin(2πz / L)·cos(2πx / L)=0. The Primitive surface… The implicit function expression is F(x,y,z)=cos(2πx / L)+cos(2πy / L)+cos(2πz / L)=0; the implicit function expression of the Diamond surface is F(x,y,z)=sin(2πx / L)·sin(2πy / L)·sin(2πz / L)+sin(2πx / L)·cos(2πy / L)·cos(2πz / L)+cos(2πx / L)·sin(2πy / L)·cos(2πz / L)+cos(2πx / L)·cos(2πy / L)·sin(2πz / L)=0, where L is the unit cell size.

[0016] Furthermore, the unit cell size L is set to 5–30 mm, the thickness of the slice layer is set to 0.03–0.05 mm, and the spacing between the parallel filler lines is set to 0.03–0.2 mm.

[0017] Further, step 3 specifically involves combining the obtained intersection points pairwise to form line segments. If the sampled points (x0, y0) in each line segment satisfy the functional relationship F(x0, y0, z... n )·F(x0,y0,z n+1 If z < 0, and the model tilt angle θ0 at that point satisfies cosθ0 > c, and the length of the line segment is greater than a set value, then the line segment is retained as the fill path; where z n z n+1 This represents the z-height of the nth and n+1th layers, and c is the set cosine threshold of the tilt angle.

[0018] Furthermore, the length of the line segment is set to 0.03 to 0.1 mm, and the cosine threshold value of the tilt angle c is set to 0.75 to 0.9.

[0019] Furthermore, step 4 specifically involves forming a support layer in the same area with the same path and different processing parameters before filling the void.

[0020] Further, step 5 specifically involves writing the contour path and the fill path into a path file recognizable by the laser selective melting device according to the standard file format. The path file is in CLI or SLC format, and the contour path and the fill path are written into different files to differentiate the settings for parameters such as processing power and scanning speed.

[0021] Furthermore, the thin-walled structure manufactured by the method contains only one melt channel in the thickness direction, and the wall thickness is less than 200 micrometers.

[0022] Furthermore, the path file is in CLI format, the powder material used is 17-4PH stainless steel, the laser power of the contour path is 135W, and the scanning speed is 400mm / s; the laser power of the filling layer path is 135W, and the scanning speed is 300mm / s; the laser power of the support layer is 60W, and the scanning speed is 1520mm / s.

[0023] Furthermore, the path file is in SLC format, the powder material used is Ti6Al4V titanium alloy, the laser power of the contour path is 280W, and the scanning speed is 1200mm / s; the laser power of the filling layer path is 200W, and the scanning speed is 1000mm / s; the laser power of the support layer is 100W, and the scanning speed is 2000mm / s.

[0024] Furthermore, the path file is in CLI format, the powder material used is AlSi10Mg aluminum alloy, the laser power of the contour path is 350W, and the scanning speed is 1150mm / s; the laser power of the filling layer path is 350W, and the scanning speed is 1000mm / s; the laser power of the support layer is 200W, and the scanning speed is 2000mm / s.

[0025] Three-period minimal curved surface lattice structures possess advantages such as lightweight, high specific stiffness, high specific strength, large surface area, and multifunctionality, showing great application potential in aerospace, medical, and other fields. Currently, such complex structures are mainly manufactured using additive manufacturing technology. This invention enables the efficient formation of laser selective melting processing paths for thin-walled three-period minimal curved surface lattice structures. The manufactured structure contains only one melt channel in the thickness direction and can fill voids generated during slicing, achieving efficient and high-quality additive manufacturing of large-scale lightweight lattice structures.

[0026] Compared with the prior art, the present invention has the following beneficial technical effects:

[0027] 1. This invention proposes a path generation and additive manufacturing method based on single-pass scanning and direct slicing. Based on the implicit function model expression F(x,y,z)=0 of the three-period minimal surface and the layer thickness adapted to the additive manufacturing equipment, a direct slicing algorithm is developed to directly generate single-pass contour path files for each layer. These files are then input into a laser selective melting additive manufacturing equipment, and processing parameters are set for manufacturing. On one hand, the wall thickness of the three-period minimal surface lattice structure manufactured by the formed path is only the width of a single melt pool, enabling thinner wall thicknesses, thereby increasing specific surface area and reducing weight. On the other hand, compared to STL model slicing, it significantly reduces the slicing process time and memory usage, and can efficiently process large-scale lattice structure models. Compared with existing methods, the method of fabricating three-period minimal surface lattice structures can significantly reduce path generation time and memory usage, and the computational efficiency is more than an order of magnitude higher than that of STL slicing. The fabricated lattice structure has a thinner wall thickness, less than 200 micrometers, which is close to the processing limit of laser selective melting equipment. The fabricated three-period minimal surface lattice structure has broad application prospects in the field of lightweight multifunctional structures.

[0028] 2. This invention proposes a method for filling voids in thin-walled three-cycle minimal curved surfaces based on parallel filling. The void region is determined by the surface tilt angle and the scanning paths of adjacent layers. A filling path is generated in the void region based on the surface function, tilt angle, and filling segment length criteria. This method can fill voids generated during the slicing of thin-walled three-cycle minimal curved surface lattice structures, significantly reducing void defects in additive manufacturing. Furthermore, it enables additive manufacturing of large-sized single-cell thin-walled three-cycle minimal curved surface lattice structures, solving the problem that void defects appear when the model cell size exceeds 5mm in existing single-pass scanning studies of three-cycle minimal curved surfaces, affecting part quality and performance.

[0029] The following will further explain the concept, specific structure, and technical effects of the present invention in conjunction with the accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention. Attached Figure Description

[0030] Figure 1 This is a flowchart of the laser selective melting additive manufacturing method for thin-walled three-period minimal curved surface lattice structures according to the present invention;

[0031] Figure 2 This is a schematic diagram of the gyroid lattice structure model (left) used for slicing and its slice outline path (right) in Embodiment 1 of the present invention;

[0032] Figure 3 This is a schematic diagram illustrating the reason for the formation of void areas in the slice in Embodiment 1 of the present invention;

[0033] Figure 4This is a schematic diagram of the intersection of a fill line and the contour paths of two adjacent layers in Embodiment 1 of the present invention;

[0034] Figure 5 This is a schematic diagram of the contour path and support layer path of the nth layer in Embodiment 1 of the present invention;

[0035] Figure 6 This is a schematic diagram of the contour path and the filling layer path of the (n+1)th layer in Embodiment 1 of the present invention;

[0036] Figure 7 This is a schematic diagram of a part manufactured according to a path file in Embodiment 1 of the present invention (unit cell size is 5mm). (Left) Thin-walled three-period minimal surface formed by additive manufacturing without adding a filling path, (Right) Thin-walled three-period minimal surface formed by additive manufacturing with a filling path.

[0037] Figure 8 This is a schematic diagram of a part manufactured according to a path file in Embodiment 1 of the present invention (unit cell size is 10mm). (Left) Thin-walled three-period minimal surface formed by additive manufacturing without adding a filling path, (Right) Thin-walled three-period minimal surface formed by additive manufacturing with a filling path.

[0038] Figure 9 This is a schematic diagram of the primitive lattice structure model used for slicing in Embodiment 2 of the present invention;

[0039] Figure 10 This is a schematic diagram of the contour path obtained by slicing the primitive lattice structure model in Embodiment 2 of the present invention;

[0040] Figure 11 This is a schematic diagram of the contour path and support layer path of the nth layer in Embodiment 2 of the present invention;

[0041] Figure 12 This is a schematic diagram of the contour path and filling layer path of the (n+1)th layer in Embodiment 2 of the present invention;

[0042] Figure 13 This is a schematic diagram of the diamond lattice structure model used for slicing in Embodiment 3 of the present invention;

[0043] Figure 14 This is a schematic diagram of the contour path obtained by slicing the diamond lattice structure model in Embodiment 3 of the present invention;

[0044] Figure 15 This is a schematic diagram of the contour path and support layer path of the nth layer in Embodiment 3 of the present invention;

[0045] Figure 16 This is a schematic diagram of the contour path and filling layer path of the (n+1)th layer in Embodiment 3 of the present invention. Detailed Implementation

[0046] The following description, with reference to the accompanying drawings, illustrates several preferred embodiments of the present invention to make its technical content clearer and easier to understand. The present invention can be embodied in many different forms, and the scope of protection of the present invention is not limited to the embodiments mentioned herein.

[0047] In the accompanying drawings, components with the same structure are indicated by the same numerical designation, and components with similar structures or functions are indicated by similar numerical designations. The dimensions and thicknesses of each component shown in the drawings are arbitrary, and the present invention does not limit the dimensions and thicknesses of each component. To make the illustrations clearer, the thickness of some components has been appropriately exaggerated in the drawings.

[0048] like Figure 1 The flowchart shown is a process for laser selective melting additive manufacturing of a thin-walled, three-period minimal curved surface lattice structure. This method includes the following steps:

[0049] Step 1: Based on the implicit function model expression F(x,y,z)=0 of the three-period minimal surface and the layer thickness adapted to the additive manufacturing equipment, obtain the single-path contour path of each layer by direct slicing;

[0050] Step 2: Traverse each plane layer, generate a series of parallel fill lines according to the set fill line spacing value, and find the intersection of the parallel fill lines with the contour path of the current layer and the contour path of the next higher layer.

[0051] Step 3: The resulting intersection points are combined in pairs to form line segments. Sampling points are taken in each line segment. If the function and tilt angle requirements are met at the same time and the line segment length is greater than the set threshold, the line segment is retained as the filling path.

[0052] Step 4: Use the filling path of this layer as a support layer, and move it up one layer to form a filling layer. Set different process parameters for the support layer and the filling layer to optimize the filling effect.

[0053] Step 5: Generate a path file that the additive manufacturing equipment can recognize based on the contour path and the filling path, input it into the additive manufacturing equipment, set the processing parameters, and carry out manufacturing.

[0054] The following description is based on specific embodiments.

[0055] Example 1

[0056] Step 1: Taking the Gyroid surface in the three-period minimal surface as an example, its implicit function expression is F(x,y,z)=sin(2πx / L)·cos(2πy / L)+sin(2πy / L)·cos(2πz / L)+sin(2πz / L)·cos(2πx / L)=0. In this embodiment, the unit cell size is set to L=30mm, and the slice layer thickness is 0.03mm. Based on the layer thickness information, the planes perpendicular to the z-axis at each height of the model are traversed to obtain the contour lines of the implicit function model F(x,y,z)=0 in each plane, which serve as the single-track contour scan path. This process is called direct slicing. The model and its slice contour path are as follows: Figure 2 As shown.

[0057] like Figure 3 As shown, during the formation of a single path from a three-cycle minimal surface slice with no thickness, if the surface tilt angle is too small, feature loss will occur in the model, forming void regions. This will lead to hole defects during additive manufacturing, affecting the performance of the manufactured part. Subsequent steps 2-4 are used to generate filling paths for the void regions.

[0058] Step 2: Set the fill line spacing h = 0.03mm, and obtain a series of parallel fill lines according to the given slope. Figure 4 The diagram shows the intersection of one of the fill lines with the contour paths of the two adjacent layers. (1)-(14) are the intersection points obtained.

[0059] Step 3: Combine the resulting intersection points pairwise to form line segments. If the sampled points (x0, y0) in each line segment satisfy the functional relationship F(x0, y0, z) n )·F(x0,y0,z n+1 If z < 0, and the model tilt angle θ0 at that point satisfies cosθ0 > c, and the length of the line segment is greater than a set value (set to 0.05 mm in this example), then the line segment is retained as the fill path. n z n+1 The z-height represents the height of the nth and n+1th layers, and c is the set cosine threshold of the tilt angle (set to 0.75 in the embodiment).

[0060] Step 4: Before filling the void, form a support layer in the same area using the same path but different processing parameters. Figure 5 , 6 The diagrams show the contour path and support layer path of the nth layer, as well as the contour path and filling layer path of the (n+1)th layer.

[0061] Step 5: Following the standard file format, write the contour path and fill path into a path file (such as CLI or SLC format) recognizable by the laser selective melting equipment. Write the contour path and fill path into different files to differentiate the settings for parameters such as processing power and scanning speed. This embodiment uses the CLI format, 17-4PH stainless steel powder, a contour path laser power of 135W, and a scanning speed of 400mm / s; a fill layer path laser power of 135W and a scanning speed of 300mm / s; and a support layer laser power of 60W and a scanning speed of 1520mm / s. The manufactured parts are as follows... Figure 7 , 8 As shown.

[0062] Example 2

[0063] Step 1: Taking the Primitive surface in the three-period minimal surface model as an example, its implicit modeling function expression is F(x,y,z)=cos(2πx / L)+cos(2πy / L)+cos(2πz / L)=0. In this embodiment, the unit cell size L=5mm and the slice layer thickness is 0.03mm. The model and its slice contour paths are as follows: Figure 9 , 10 As shown.

[0064] Step 2: Set the fill line spacing h = 0.2mm, obtain a series of parallel fill lines according to the given slope, and find the intersection of the parallel fill lines with the contour path of this layer and the contour path of the higher layer.

[0065] Step 3: Combine the resulting intersection points pairwise to form line segments. If the sampled points (x0, y0) in each line segment satisfy the functional relationship F(x0, y0, z) n )·F(x0,y0,z n+1 If z < 0, and the model tilt angle θ0 at that point satisfies cosθ0 > c, and the length of the line segment is greater than a set value (0.03 mm in this example), then the line segment is retained as the fill path. n z n+1 The z-height represents the height of the nth and n+1th layers, and c is the set cosine threshold of the tilt angle (set to 0.9 in this embodiment).

[0066] Step 4: Before filling the void, form a support layer in the same area using the same path but different processing parameters. Figure 11 This shows the contour path and support layer path of the nth layer. Figure 12 A schematic diagram showing the contour path and filling layer path of the (n+1)th layer is presented.

[0067] Step 5: Following the standard file format, write the contour path and fill path into a path file recognizable by the laser selective melting equipment. This embodiment uses the SLC format, employs Ti6Al4V titanium alloy powder, and features a contour path laser power of 280W and a scanning speed of 1200mm / s; a fill layer path laser power of 200W and a scanning speed of 1000mm / s; and a support layer laser power of 100W and a scanning speed of 2000mm / s.

[0068] Example 3

[0069] Step 1: Taking the Diamond surface in the three-period minimal surface as an example, its implicit function expression is F(x,y,z)=sin(2πx / L)·sin(2πy / L)·sin(2πz / L)+sin(2πx / L)·cos(2πy / L)·cos(2πz / L)+cos(2πx / L)·sin(2πy / L)·cos(2πz / L)+cos(2πx / L)·cos(2πy / L)·sin(2πz / L)=0. In this embodiment, the unit cell size L=20mm and the slice layer thickness is 0.05mm. The model and its slice contour paths are as follows: Figure 13 , 14 As shown.

[0070] Step 2: Set the fill line spacing h = 0.05mm, obtain a series of parallel fill lines according to the given slope, and find the intersection of the parallel fill lines with the contour path of this layer and the contour path of the higher layer.

[0071] Step 3: Combine the resulting intersection points pairwise to form line segments. If the sampled points (x0, y0) in each line segment satisfy the functional relationship F(x0, y0, z) n )·F(x0,y0,z n+1 If z < 0, and the model tilt angle θ0 at that point satisfies cosθ0 > c, and the length of the line segment is greater than a set value (set to 0.1 mm in this example), then the line segment is retained as the fill path. n z n+1 The z-height represents the height of the nth and n+1th layers, and c is the set cosine threshold of the tilt angle (set to 0.9 in the embodiment).

[0072] Step 4: Before filling the void, form a support layer in the same area using the same path but different processing parameters to improve the collapse of the filling layer. Figure 15 This shows the contour path and support layer path of the nth layer. Figure 16 A schematic diagram showing the contour path and filling layer path of the (n+1)th layer is presented.

[0073] Step 5: Following the standard file format, write the contour path and fill path into a path file recognizable by the additive manufacturing equipment. This embodiment uses a laser selective melting process, with the path output in CLI format. The powder material used is AlSi10Mg aluminum alloy. The laser power for the contour path is 350W, and the scanning speed is 1150mm / s; the laser power for the fill layer path is 350W, and the scanning speed is 1000mm / s; the laser power for the support layer is 200W, and the scanning speed is 2000mm / s.

[0074] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A laser additive manufacturing method for a thin-walled, three-period minimal curved surface lattice structure, characterized in that, The method includes the following steps: Step 1: Based on the implicit function model expression F(x, y, z)=0 of the three-period minimum surface and the layer thickness adapted to the laser selective melting additive manufacturing equipment, the single-track contour path of each layer is obtained by direct slicing. The specific process of Step 1 is as follows: based on the layer thickness information, the planes perpendicular to the z-axis at each height of the model are traversed to obtain the contour lines of the implicit function model F(x, y, z)=0 in each plane, which are used as the single-track contour scanning path. This process is called direct slicing. Step 2: Traverse each plane layer, generate a series of parallel fill lines according to the set fill line spacing value, and find the intersection of the parallel fill lines with the contour path of the current layer and the contour path of the next higher layer. Step 3: The resulting intersection points are combined in pairs to form line segments. Sampling points are taken from each line segment. If the function expression, tilt angle requirements, and line segment length are all satisfied, the line segment is retained as a fill path. Specifically, Step 3 involves combining the resulting intersection points in pairs to form line segments. If the sampling points (x0, y0) taken from each line segment satisfy the functional relationship F(x0, y0, z...)... n )·F(x0, y0, z n+1 If z < 0, and the model tilt angle θ0 at that point satisfies cosθ0 > c, and the length of the line segment is greater than a set value, then the line segment is retained as the fill path; where z n z n+1 This represents the z-height of the nth and n+1th layers, where c is the set cosine threshold of the tilt angle; Step 4: Use the filling path of this layer as a support layer, and move it up one layer to form a filling layer. The support layer and the filling layer are set with different process parameters to optimize the filling effect. Specifically, Step 4 is to form a support layer in the same area with the same path and different processing parameters before filling the void. Step 5: Generate a path file that the additive manufacturing equipment can recognize based on the contour path and the filling path, input it into the additive manufacturing equipment, set the processing parameters, and carry out manufacturing.

2. The laser additive manufacturing method for thin-walled three-period minimal curved surface lattice structures as described in claim 1, characterized in that, The length of the line segment is set to 0.03~0.1 mm, and the cosine threshold value of the tilt angle is set to 0.75~0.

9.

3. The laser additive manufacturing method for thin-walled three-period minimal curved surface lattice structures as described in claim 1, characterized in that, Step 5 specifically involves writing the contour path and the fill path into a path file that can be recognized by the laser selective melting equipment according to the standard file format. The path file is in CLI or SLC format. The contour path and the fill path are written into different files to distinguish the processing power and scanning speed parameters.

4. The laser additive manufacturing method for thin-walled three-period minimal curved surface lattice structures as described in claim 1, characterized in that, The thin-walled structure manufactured by the method has only one melt channel in the thickness direction and a wall thickness of less than 200 micrometers.

5. The laser additive manufacturing method for a thin-walled three-period minimal curved surface lattice structure as described in claim 1, characterized in that, The path file is in CLI format, the powder material used is 17-4PH stainless steel, the laser power of the contour path is 135 W, and the scanning speed is 400 mm / s; the laser power of the filling layer path is 135 W, and the scanning speed is 300 mm / s; the laser power of the support layer is 60 W, and the scanning speed is 1520 mm / s.

6. The laser additive manufacturing method for a thin-walled, three-period minimal curved surface lattice structure as described in claim 1, characterized in that, The path file is in SLC format, using Ti6Al4V titanium alloy powder material. The laser power for the contour path is 280W, and the scanning speed is 1200 mm / s; the laser power for the filling layer path is 200 W, and the scanning speed is 1000 mm / s; the laser power for the support layer is 100 W, and the scanning speed is 2000 mm / s.

7. The laser additive manufacturing method for thin-walled three-period minimal curved surface lattice structures as described in claim 1, characterized in that, The path file is in CLI format, the powder material used is AlSi10Mg aluminum alloy, the laser power of the contour path is 350 W, and the scanning speed is 1150 mm / s; the laser power of the filling layer path is 350 W, and the scanning speed is 1000 mm / s; the laser power of the support layer is 200 W, and the scanning speed is 2000 mm / s.

Images