A method for additive manufacturing of a lightweight non-rotating body cabin section

Abstract

The present application relates to a kind of lightweight non-rotating body cabin section additive manufacturing method, belong to additive manufacturing technical field, for the one of the problems such as the difficult control of the rib camber forming angle of existing additive manufacturing method, difficult to actively optimize the structural bearing capacity of cabin section, low modeling efficiency.The lightweight non-rotating body cabin section additive manufacturing method of the present application, including S1, construct non-rotating body cabin section model;S2, to cabin section model is carried out additive manufacturing preprocessing;S3, according to the path and support data after optimization are carried out additive manufacturing printing;S4, to the cabin section of printing forming is postprocessed.The additive manufacturing method of the present application can obtain the camber that meets the requirement, improve the effect of structural lightweight, improve the efficiency of modeling and additive manufacturing.

Description

Technical Field

[0001] This invention relates to the field of additive manufacturing technology, and in particular to an additive manufacturing method for a lightweight non-rotating body section. Background Technology

[0002] With the advancement of modern high-end equipment technology, the shapes of compartments with mesh-reinforced structures, widely used in aerospace and transportation, are gradually breaking through the limitations of traditional rotating bodies and evolving towards complex irregular curved surfaces of non-rotating bodies with hyperbolic curvature and multi-section transitions. As additive manufacturing technology is increasingly used in lightweight structure manufacturing, modeling non-rotating curved mesh-reinforced structures for additive manufacturing has become a challenge in additive manufacturing technology.

[0003] Existing modeling methods for non-rotational surface mesh-stiffened structures in additive manufacturing typically employ the surface free deformation method. This method first establishes a mapping relationship between a simple surface and a set of control points, then deforms the simple surface stiffened shell into a surface stiffened shell. However, this method struggles to generate uniform and continuous geometric paths for the mesh stiffeners on complex surfaces, easily leading to problems such as mesh stiffener distortion, breakage, or uneven spacing. Furthermore, since the free deformation mapping relationship is determined by the surface control points, and the positions and spacing of these control points are generally automatically generated, stress concentrations can easily occur in regions of abrupt curvature changes when the irregular surface causes uneven structural stiffness distribution. Moreover, it is difficult to actively optimize and adjust these stresses by adjusting parameters. Summary of the Invention

[0004] Based on the above analysis, this invention aims to provide an additive manufacturing method for lightweight non-rotating body sections, addressing one of the problems of existing additive manufacturing methods: difficulty in controlling the position and shape of mesh reinforcement surfaces during modeling, difficulty in actively optimizing the structural load-bearing capacity of the section through parameterization, and low modeling efficiency. The objective of this invention is mainly achieved through the following technical solutions.

[0005] This invention provides an additive manufacturing method for a lightweight non-rotating body section, comprising the following steps: S1. Construct a model of a non-rotating body section; S2. Perform additive manufacturing preprocessing on the compartment model; S3. Perform additive manufacturing printing based on the optimized path and support data; S4. Post-process the printed compartment.

[0006] Furthermore, step S1 also includes: S11. Construct a non-rotating irregular curved surface model of the outer surface of the compartment, and offset the outer surface surface inward at equal intervals along the normal direction to generate the reference surface of the inner surface of the compartment.

[0007] Furthermore, step S1 also includes: S12. Using the UV parametric mapping method, construct and generate a mesh rib model on the reference surface.

[0008] Furthermore, step S12 also includes: extracting the UV parameter domain of the reference surface; constructing a mesh pattern with a preset topological shape in the two-dimensional UV parameter domain; mapping the two-dimensional mesh pattern back to three-dimensional space along the surface normal to generate the center line of the mesh ribs; and generating a three-dimensional mesh rib entity based on the center line and merging it with the reference surface.

[0009] Furthermore, the preprocessing in step 2 includes slicing, conformal scan path planning, support structure generation, and support structure mechanical simulation.

[0010] Furthermore, in step S3, a laser selective melting process is used, and titanium alloy, aluminum alloy or high-temperature alloy powder is selected; during the printing process, a partitioned scanning strategy is adopted, and the laser power is controlled within the range of 250W-350W, and the scanning speed is controlled within the range of 1000mm / s-1500mm / s.

[0011] Furthermore, S11 also includes determining the additive direction, determining the bottom curve of the reference surface, and setting the planar curve of the bottom curve.

[0012] Furthermore, instead of step S12, step S1 also includes: S12': Based on the initial geometric parameters of the mesh reinforcement, construct the mesh curve CL on the reference surface, and construct the normal segment of the reference surface at the intersection of each mesh curve CL.

[0013] Furthermore, S12' also includes: constructing each mesh reinforcement surface using each mesh curve CL and normal segment as the framework for the mesh reinforcement surface.

[0014] Furthermore, S12' also includes: checking whether the mesh rib surface meets the additive manufacturing forming angle requirements; if not, iteratively optimizing the mesh rib surface until all mesh rib surfaces meet the additive manufacturing forming angle requirements.

[0015] Furthermore, S12' also includes that the modeling sequence of the mesh reinforcement surface is consistent with the additive direction. Taking the bottom edge mesh intersection point P1 on the bottom edge curve L1 as the modeling starting point, the mesh curve point Pn is determined layer by layer according to the mesh tilt angle θ and the mesh spacing H, and then the position of the mesh curve CL on the reference surface is determined, and finally the modeling of the mesh reinforcement surface 21 is completed.

[0016] Furthermore, S12' also includes the following steps: S121', Create a set of cross-sectional curves LS for the reference surface 11 along the additive manufacturing direction; including: determining the additive manufacturing direction and the bottom edge of the reference surface, the bottom edge curve L1 of the reference surface is a planar curve, creating a set of planes with equal spacing parallel to the bottom edge plane of the reference surface, and creating a set of cross-sectional curves LS that intersects the plane set with the reference surface. S122', Construct the set of bottom edge grid intersection points P1S on the bottom edge curve L1; including: setting the grid spacing H of the grid rib surface, setting the grid rib surface to intersect at the bottom edge of the reference surface, and determining the position of the set of bottom edge grid intersection points P1S on the bottom edge curve L1 according to the grid spacing H. S123', Create a set of grid curve points PS along the additive manufacturing direction; Set the grid tilt angle θ of the grid rib surface, and starting from the grid intersection point set PS1, determine the set of grid curve points PnS on each layer of cross-sectional curve Ln in the cross-sectional curve set LS one by one according to the grid tilt angle θ, and then create the set of grid curve points PS. S124', Create the mesh curve CL based on the mesh curve point set PS; including: connecting the mesh curve points of each mesh curve CL on each layer of cross-sectional curve to obtain all the mesh curves CL on the reference surface; S125' Generate mesh reinforcement surfaces based on mesh curves CL; including: setting the mesh reinforcement height W of the mesh reinforcement surface, and generating all mesh reinforcement surfaces one by one according to the position of each mesh curve CL.

[0017] Furthermore, S122 also includes determining the (n+1)th layer grid curve point P. n+1 Steps: S123'-1, Given the nth layer grid curve point P n , through P n Construct a plane perpendicular to the intersection line of the nth layer; S123'-2, Construct the intersection point P of this plane and the line of intersection with the (n+1)th layer. n+1 '; S123'-3, Measurement P n and P n+1 The distance d between them; S123'-4, Take point P on the intersection line of the (n+1)th layer. n+1 , making P n+1 and P n+1 The arc length between the two points is d×tanθ.

[0018] Furthermore, S125' also includes the following steps: S125'-1, Take the set of intersection points between grid curves CL; S125'-2. At the intersection point, construct the normal segment of the reference surface. The length of the normal segment is equal to the height H of the mesh reinforcement. S125'-3. Using the Nth mesh curve and the normal segment on the Nth mesh curve as the framework of the Nth mesh reinforcement surface, construct the Nth mesh reinforcement surface; S125'-4, take N=N+1, repeat steps S125'-3 and S125'-4 until all the mesh reinforcement surfaces are created.

[0019] Furthermore, S12' also includes: S126': Check whether the mesh rib surface meets the additive manufacturing forming angle requirements. If not, reduce the mesh tilt angle θ and repeat S123' to S126' until all mesh rib surfaces meet the additive manufacturing forming angle requirements.

[0020] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects: 1. The additive manufacturing method of the present invention, by modeling according to the parameters of the mesh ribs in the modeling step of S12 or S12', gets rid of the dependence on the axis of rotational symmetry and can effectively complete the modeling of additive manufacturing of non-rotating irregular curved surface compartments; it can effectively avoid the problems of rib surface distortion, breakage and uneven spacing caused by direct projection or deformation, and realize the native generation of mesh rib surfaces on complex curved surfaces.

[0021] 2. The additive manufacturing method of the present invention, in step S12', by aligning the modeling sequence of the mesh reinforcement surface with the additive direction F, and by determining the mesh curve points Pn layer by layer based on the mesh tilt angle θ and mesh spacing H, makes the mesh tilt angle θ directly related to the additive forming angle. This allows for optimization of the additive forming angle by adjusting the mesh tilt angle θ, ensuring that the process risk of an excessively small forming angle can be avoided during the modeling stage, thus guaranteeing the manufacturability of the model from the source. Simultaneously, since the modeling process automatically ensures the symmetry of the mesh reinforcement curve, the symmetry of the mesh reinforcement model can be guaranteed for non-rotating body sections that are inherently symmetrical. Furthermore, since the mesh tilt angle θ and mesh spacing H directly affect the strength and stiffness of the mesh-reinforced structure, precise adjustment of these two parameters during modeling can also optimize the structural performance such as the load-bearing capacity of the mesh reinforcement, improving the lightweight effect of the structure.

[0022] 3. The additive manufacturing method of the present invention includes a step of checking the forming angle of the mesh reinforcement surface in step S126', and for cases where the forming angle requirement is not met, iterative optimization of the mesh reinforcement model is performed by reducing the mesh tilt angle, so that the generated irregular curved surface mesh reinforcement structure model can meet the process constraints of additive manufacturing on the forming angle, which significantly improves the modeling efficiency and processing efficiency.

[0023] 4. The additive manufacturing method of the present invention, since the modeling steps can be clearly described as algorithms, is convenient for secondary development through modeling software to achieve automated modeling, which greatly improves the modeling speed and structural optimization design efficiency.

[0024] 5. The additive manufacturing method of the present invention, through step S125', constructs normal segments at the intersection of mesh curves, and generates mesh reinforcement surfaces based on the mesh curves and normal segments, ensuring the geometric compatibility between the mesh reinforcement surfaces and the reference surfaces, improving the mechanical support performance of the mesh reinforcement surfaces on the reference surfaces, reducing the risk of structural failure due to geometric deviations during additive manufacturing, and providing an accurate geometric model basis for subsequent additive manufacturing; by automatically generating mesh reinforcement surfaces, the modeling speed and computational stability of complex irregular curved surface reinforcement structures are greatly improved.

[0025] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained through the embodiments described and the accompanying drawings, which are particularly pointed out. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the additive manufacturing method for a lightweight non-rotating body section according to an embodiment of the present invention; Figure 2 This is a structural schematic diagram of the lightweight non-rotating body section according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the reference surface 11 in an embodiment of the present invention; Figure 4 This is a schematic diagram of step S12' in Embodiment 2 of the present invention; Figure 5 This is a schematic diagram of the modeling process in step S122' of Embodiment 2 of the present invention; Figure 6 This is a schematic diagram of step S125' in Embodiment 2 of the present invention; Figure 7 This is a schematic diagram showing the dimensions of the bottom curve L1 and the top curve Ld of the reference surface 11 in Embodiment 2 of the present invention. Figure 8 This is a schematic diagram of the modeling process in step S124' of Embodiment 2 of the present invention; Figure 9 This is a schematic diagram of the modeling process in step S125' of Embodiment 2 of the present invention; Figure 10This is a schematic diagram of the angle inspection results for the additive manufacturing of irregular curved surface mesh reinforcement with a mesh tilt angle of θ=45° in Embodiment 2 of the present invention. Figure 11 This is a schematic diagram showing the angle inspection results of the additive manufacturing forming of irregular curved surface mesh reinforcement with a mesh tilt angle of θ=30° in Embodiment 2 of the present invention.

[0027] Figure label: 1-Skin; 11-Reference surface; 2-Mesh rib; 21-Mesh rib surface; L1 - Bottom curve; Ld - Top curve; P1 - Bottom mesh intersection point; P1S - Bottom mesh intersection point set; LS - Section curve set; CL - Mesh curve; F - Additive direction. Detailed Implementation

[0028] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0029] Example 1 In a specific embodiment of the present invention, in order to solve one of the problems of difficulty in controlling the position and shape of the rib surface in existing additive manufacturing methods, such as... Figure 1 As shown, an additive manufacturing method for a lightweight non-rotating body section is disclosed, including the following steps: S1. Parametrically construct a non-rotating body section model; S2. Perform additive manufacturing preprocessing on the compartment model; S3. Perform additive manufacturing printing based on the optimized path and support data; S4. Post-process the printed compartment.

[0030] Furthermore, such as Figure 2 and Figure 3 As shown, in order to solve the problem of the inability to parametrically model the free deformation process of a curved surface, step S1 also includes: S11. Based on the geometric parameters of the skin 1 of the compartment, construct the reference surface 11 of the skin.

[0031] This embodiment takes an irregular curved surface with planar curves at both ends as an example. Step S11 also includes the following steps: S111, Set the edge curve of at least one end of the reference surface 11 to be a planar curve; S112. Determine the height parameters and at least the dimension parameters of the two end edges of the reference surface 11; S113. Generate a model of the reference surface 11 based on the dimensional parameters of the reference surface 11.

[0032] This embodiment sets the edge curve of at least one end of the reference surface 11 as a planar curve, which can determine the additive direction and provide a stable additive bottom edge, and also provide a geometric basis for the accurate arrangement of the subsequent mesh rib surface 21; by determining the height of the reference surface 11 and the size parameters of the edge lines at both ends, the non-rotational irregular surface model can be accurately generated according to the size parameters.

[0033] Furthermore, such as Figure 2 As shown, in order to solve the problems of distortion, breakage and uneven spacing that easily occur in the mesh-rib curved surface model, step S1 also includes: S12. Using the UV parametric mapping method, construct the model of mesh reinforcement 2 based on the reference surface 11.

[0034] Specifically, step S12 further includes: extracting the UV parameter domain of the reference surface 11; constructing a mesh pattern with a preset topological shape in the two-dimensional UV parameter domain; mapping the two-dimensional mesh pattern back to three-dimensional space along the surface normal to generate the center line of the mesh reinforcement 2; and generating a three-dimensional solid model of the mesh reinforcement 2 based on the center line and merging it with the reference surface 11.

[0035] In the additive manufacturing method of this embodiment, in the mesh rib modeling of step S12, UV parameter domain mapping is used instead of rotation array, which gets rid of the dependence on rotational symmetry axis and can effectively complete the modeling of additive manufacturing of non-rotating irregular curved surface compartments. Instead of deforming the existing stiffened shell as a whole, the UV parameter domain of the non-rotating inner skin is extracted, and a regular mesh is constructed in the two-dimensional parameter domain and then mapped back to three-dimensional space. This can effectively avoid the problems of rib surface distortion, breakage and uneven spacing caused by direct projection or deformation, and realize the native generation of mesh rib surface on complex curved surfaces.

[0036] Furthermore, the preprocessing in step 2 includes slicing, conformal scan path planning, support structure generation, and support structure mechanical simulation.

[0037] Furthermore, in step S3, a laser selective melting process is used, and titanium alloy, aluminum alloy or high-temperature alloy powder is selected; during the printing process, a partitioned scanning strategy is adopted, and the laser power is controlled within the range of 250W-350W, and the scanning speed is controlled within the range of 1000mm / s-1500mm / s.

[0038] Example 2 This embodiment discloses an additive manufacturing method for a lightweight non-rotating body segment. The steps are basically the same as those of the additive manufacturing method for a lightweight non-rotating body segment in Embodiment 1. The difference lies in that, to address one of the problems of difficulty in controlling the forming angle of the rib curved surface of the non-rotating body segment, difficulty in actively optimizing the structural bearing capacity of the segment, and complexity of the modeling process, step S12 is replaced by step S12' in this embodiment: S12': Construct mesh reinforcement surface 2 based on the mesh reinforcement size parameters and generate the mesh reinforcement model; The additive manufacturing method for the lightweight non-rotating body section in this embodiment constructs a mesh reinforcement surface 2 based on the mesh reinforcement's dimensional parameters. This facilitates the optimization of the additive forming angle, structural strength, and stiffness of the model through active control and adjustment of the mesh reinforcement's dimensional parameters. Since modeling is based on the reference surface 11 and the geometric parameters of the mesh reinforcement, it can be implemented through programming, significantly improving modeling efficiency. Because the modeling steps can be clearly described as algorithms, automated modeling can be achieved after secondary development of the modeling software, greatly improving modeling speed and structural optimization design efficiency.

[0039] Specifically, in step S11 of this embodiment, Specifically, step S12' includes: the modeling sequence of the mesh rib surface 21 is consistent with the additive direction F. Taking the bottom edge mesh intersection point P1 on the bottom edge curve L1 as the modeling starting point, the mesh curve point Pn is determined layer by layer according to the mesh tilt angle θ and the mesh spacing H, and then the position of the mesh curve CL on the reference surface is determined, and finally the modeling of the mesh rib surface 21 is completed.

[0040] It should be noted that the additive forming angle refers to the angle between the building direction and the model surface during the printing process, also known as the overhang angle. A forming angle greater than a threshold (generally 45°) allows for forming, while an angle less than the threshold prevents forming.

[0041] In this embodiment, in step S12', the modeling sequence of the mesh reinforcement surface 21 is aligned with the additive direction F. Based on the mesh tilt angle θ and mesh spacing H, the mesh curve points Pn are determined layer by layer. This ensures that the mesh tilt angle θ is directly related to the additive forming angle, allowing for optimization of the additive forming angle by adjusting the mesh tilt angle θ. This avoids the process risk of an excessively small forming angle during the modeling stage, guaranteeing the manufacturability of the model from the outset. Furthermore, since the modeling sequence starts from the mesh intersection point P1 on the bottom curve L1, ensuring the symmetry of the mesh intersection point P1 on the bottom curve L1 automatically guarantees the symmetry of the mesh reinforcement curve in subsequent modeling processes. For the reference surface 11, which inherently possesses symmetry, the symmetry of the mesh reinforcement surface 21 can be guaranteed. Additionally, since the mesh tilt angle θ and mesh spacing H directly affect the strength and stiffness of the mesh-reinforced structure, precise adjustment of these two parameters during modeling can optimize the structural performance of the mesh reinforcement, such as its load-bearing capacity, thereby improving the lightweight effect of the structure.

[0042] Specifically, such as Figure 4 As shown, step S12' further includes the following steps: S121', Create a set of cross-sectional curves LS of the reference surface 11 along the additive manufacturing direction; including: determining the additive manufacturing direction and the bottom edge of the reference surface 11, the bottom edge curve L1 of the reference surface 11 is a planar curve, creating a set of equally spaced planes parallel to the bottom edge plane of the reference surface 11, and creating a set of cross-sectional curves LS that intersect the plane set with the reference surface 11.

[0043] Preferably, considering the problem that the generated mesh reinforcement shape is prone to errors, in S121', the planes parallel to the bottom edge plane of the reference surface 11 are concentrated, and the spacing between each plane should be less than 1 / 10 of the minimum radius of curvature of the reference surface 11, so as to reduce the error of the generated mesh reinforcement shape and make the mesh reinforcement surface 21 smoother.

[0044] Furthermore, in order to address the difficulty of actively designing mesh-reinforced surfaces through parameters, such as... Figure 4 As shown, step S12' further includes: S122', Construct the set of bottom edge grid intersection points P1S on the bottom edge curve L1; including: setting the grid spacing H of the grid rib surface 21, setting the grid rib surface 2 to intersect at the bottom edge of the reference surface 11, and determining the position of the set of bottom edge grid intersection points P1S on the bottom edge curve L1 according to the grid spacing H.

[0045] It should be noted that, since the arc length and chord length are almost equal when the curve length is very small, the grid spacing H is calculated based on the arc length between the two intersection points for ease of plotting.

[0046] Furthermore, in step S122', the grid spacing H can be set to an equal arc length spacing, and the position of the bottom grid intersection point set P1S is determined using the equal arc length spacing method; the grid spacing W can also be set to a variable spacing according to the needs of structural optimization design.

[0047] Furthermore, to address the issue that the forming angle of the mesh reinforcement surface and the stiffness and strength of the mesh reinforcement cannot be actively controlled through parameters, such as... Figure 4 As shown, step S12' further includes: S123', Create a set of grid curve points PS along the additive manufacturing direction; Set the grid tilt angle θ of the grid rib surface 21, and starting from the grid intersection point set PS1, determine the set of grid curve points PnS on each layer of cross-sectional curve Ln in the cross-sectional curve set LS one by one according to the grid tilt angle θ, and then create the set of grid curve points PS.

[0048] Furthermore, to prevent the geometric shape of the mesh rib surface 21 from being discontinuous and uneven, such as... Figure 5 As shown, step S123' further includes determining the grid curve point P of the grid curve CL in the (n+1)th layer. n+1 Steps: S123'-1, Given the nth layer grid curve point P n , through P n Construct a plane perpendicular to the intersection line of the nth layer; S123'-2, Construct the intersection point P of this plane and the line of intersection with the (n+1)th layer. n+1 '; S123'-3, Measurement P n and P n+1 The distance d between them; S123'-4, Take point P on the intersection line of the (n+1)th layer. n+1 , making P n+1 and P n+1 The arc length between the two points is d×tanθ.

[0049] In step S123' of this embodiment, the grid curve point set PS is determined by iteratively layer by layer, which realizes the accurate tracking and positioning of the grid curve CL on the complex surface, ensuring the continuity and consistency of the geometric shape of the grid curve CL, and providing parameter basis for the subsequent generation of high-quality grid rib surface 21.

[0050] Furthermore, such as Figure 4 As shown, step S12' further includes: S124', Create the mesh curve CL based on the mesh curve point set PS; including: connecting the mesh curve points of each mesh curve CL on each layer of cross section curve to obtain all the mesh curves CL on the reference surface 11; S125' Generate mesh reinforcement surface 21 based on mesh curve CL; including: setting the mesh reinforcement height W of mesh reinforcement surface 21, and generating all mesh reinforcement surfaces 21 one by one according to the position of each mesh curve CL.

[0051] Furthermore, in order to address the problem of low geometric compatibility between the mesh surface 21 and the reference surface 11, such as... Figure 6 As shown, S125' of this embodiment further includes the following steps: S125'-1, Take the set of intersection points between grid curves CL; S125'-2. At the intersection point, construct the normal segment of the reference surface 11. The length of the normal segment is equal to the height H of the mesh reinforcement. S125'-3. Using the Nth mesh curve and the normal segment on the Nth mesh curve as the framework of the Nth mesh reinforcement surface 21, construct the Nth mesh reinforcement surface 21; S125'-4, take N=N+1, repeat steps S125'-3 and S125'-4 until all the mesh reinforcement surfaces 21 are made.

[0052] In step S125' of this embodiment, normal segments are constructed at the intersections of mesh curves CL, and mesh stiffener surfaces 21 are generated using mesh curves CL and normal segments as a reference framework. This ensures the geometric compatibility between mesh stiffener surfaces 21 and reference surfaces 11, improves the mechanical support performance of mesh stiffener surfaces 21 on reference surfaces 11, reduces the risk of structural failure due to geometric deviations during additive manufacturing, and provides an accurate geometric model basis for subsequent additive manufacturing. By automatically generating mesh stiffener surfaces in steps S125'-4, the modeling speed and computational stability of complex irregular surface stiffened structures are significantly improved.

[0053] Preferably, the height H of the mesh reinforcement is 5-20mm.

[0054] Furthermore, in order to address the issue that the forming angle of the mesh reinforcement surface cannot fully conform to the process constraints such as the forming angle of additive manufacturing, such as... Figure 4 As shown, step S12' in this embodiment further includes: S126': Check whether the mesh rib surface 21 meets the additive manufacturing forming angle requirements. If not, reduce the mesh tilt angle θ and repeat S123' to S126' until all mesh rib surfaces 21 meet the additive manufacturing forming angle requirements.

[0055] When inspecting the curved surface 21 of the mesh reinforcement, the results of the additive manufacturing forming angle of the irregular curved surface mesh reinforcement were analyzed using simulation software.

[0056] Preferably, considering that when the mesh tilt angle θ is greater than 45°, the forming angle is too large to form and the forming angle is too large to be formed, while when it is less than 30°, the circumferential strength of the mesh ribs is too weak, in step S300, the adjustment range of the mesh tilt angle θ is 30°-45°, so as to achieve the effect of balancing the forming effect and the strength of the mesh ribs.

[0057] In step S126' of this embodiment, the process of generating the mesh rib surface 21 includes a step of checking the forming angle of the mesh rib surface. For cases where the forming angle requirement is not met, the mesh rib model is iteratively optimized by reducing the mesh tilt angle. This enables the generated irregular curved surface mesh rib structure model to meet the process constraints of additive manufacturing on the forming angle. It can effectively avoid the shortcomings of traditional free deformation methods for curved surfaces, where the deformation result is determined by the mapping relationship, making it difficult to directly control the forming angle of the rib surface. This significantly improves the forming success rate and structural reliability of complex irregular curved surface structures in the additive manufacturing process.

[0058] For example, this embodiment uses Figure 3 Taking the reference surface 11 shown as an example, the specific example of step S12' in this embodiment is as follows: First, in step S11, the bottom curve L1 and top curve Ld of the reference surface 11 are determined. Both curves are planar curves and their planes are parallel. The height of the reference surface 11 is 300mm. The dimensional parameters of the bottom curve L1 and the top curve Ld are as follows: Figure 7 The bid is marked.

[0059] like Figure 8 As shown, in step S121', taking the plane where the bottom curve L1 is located as the bottom edge of the additive manufacturing, a set of planes parallel to the bottom edge plane of the reference surface 11 is made at intervals of 10mm, and the set of cross-sectional curves LS of the plane set and the reference surface 11 is made.

[0060] like Figure 5 As shown, in step S122', the intersection points of the bottom edge of the reference surface 11 of the mesh reinforcement and the mesh are set to be distributed with equal arc length spacing, and the arc length spacing is equal to the mesh spacing H=55mm; according to the size parameters of curve 2 and the arc length spacing, the bottom edge mesh intersection point set P1S of 28 points on the bottom edge of the reference surface 11 is obtained.

[0061] Four of the intersection points lie within two symmetric planes of the surface, therefore the set of bottom intersection points is also symmetric about the two planes. For surfaces that are inherently symmetric, if the symmetry of the bottom mesh intersection points is guaranteed, the subsequent modeling process will automatically ensure the symmetry of the mesh reinforcement.

[0062] like Figure 5 and Figure 9 As shown, in step S123', the grid tilt angle is set to θ = ±45°; taking the grid intersection point set of the bottom edge of the reference surface 11 (the first layer intersection line) as the starting point, the grid curve intersection points on the second layer intersection line are determined. This includes: drawing a plane perpendicular to the first layer intersection line through point P1, drawing the intersection point P2' of this plane with the second layer intersection line, measuring the distance d = 10.02mm between P1 and P2', taking point P2 on the second layer intersection line, such that the arc length between P2 and P2' is d × tan45° = 5.79mm; and so on, drawing the grid curve intersection point set PnS on the cross-sectional curve Ln of each layer, and then drawing the grid curve point set PS.

[0063] like Figure 8 As shown, in step S124', spline curves are constructed by connecting the grid curve points of each grid curve CL on each layer of cross-sectional curve to obtain a single grid curve CL. All grid curves are constructed using this method, thereby determining the positions of all grid curves CL on the reference surface 11.

[0064] like Figure 9As shown, in step S125', the height W of the mesh reinforcement surface 21 is set to 20mm, the intersection set of the mesh curves is drawn, and the normal segment of the reference surface 11 is drawn at the intersection point. The length of the normal segment is the height W of the mesh reinforcement. The Nth mesh curve and the normal segment on the Nth mesh curve are used as the framework of the Nth mesh reinforcement surface 21, and the Nth mesh reinforcement surface 21 is drawn. In this way, all mesh reinforcement surfaces 21 are drawn.

[0065] like Figure 10 and Figure 11 As shown, in step S126', the forming angle results of the additive manufacturing of irregular curved surface mesh reinforcement are checked by simulation software.

[0066] Figure 10 The results of the additive manufacturing forming angle inspection for irregular curved surface mesh reinforcement when the mesh tilt angle θ=45° is shown; the red part in the mesh reinforcement surface 21 in the figure is the part that does not meet the additive manufacturing forming angle requirements.

[0067] Since the structure does not meet the requirements for additive manufacturing forming angle, reduce the mesh tilt angle θ to θ=±30°, repeat steps S125' and S126', and recreate all mesh rib surfaces 21.

[0068] Figure 11 The figure shows the additive manufacturing forming angle results of the irregular curved surface mesh reinforcement when the mesh tilt angle θ=30°. The results show that the curved surface 21 of the mesh reinforcement meets the additive manufacturing forming angle requirements.

[0069] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. An additive manufacturing method for a lightweight non-rotating body section, characterized in that, Includes the following steps: S1. Construct a model of a non-rotating body section; S2. Perform additive manufacturing preprocessing on the compartment model; S3. Perform additive manufacturing printing based on the optimized path and support data; S4. Post-process the printed compartment.

2. The additive manufacturing method for the lightweight non-rotating body section according to claim 1, characterized in that, Step S1 also includes: S11. Construct a non-rotating irregular curved surface model of the outer surface of the compartment, and offset the outer surface surface inward at equal intervals along the normal direction to generate the reference surface of the inner surface of the compartment.

3. The additive manufacturing method for the lightweight non-rotating body section according to claim 2, characterized in that, Step S1 also includes: S12. Using the UV parametric mapping method, construct and generate a mesh rib model on the reference surface.

4. The additive manufacturing method for the lightweight non-rotating body section according to claim 3, characterized in that, Step S12 further includes: extracting the UV parameter domain of the reference surface; constructing a mesh pattern with a preset topological shape in the two-dimensional UV parameter domain; mapping the two-dimensional mesh pattern back to three-dimensional space along the surface normal to generate the center line of the mesh ribs; and generating a three-dimensional mesh rib entity based on the center line and merging it with the reference surface.

5. The additive manufacturing method for the lightweight non-rotating body section according to claim 2, characterized in that, S11 also includes determining the additive direction, determining the bottom curve of the reference surface, and setting the planar curve of the bottom curve.

6. The additive manufacturing method for the lightweight non-rotating body section according to claim 5, characterized in that, Step S1 also includes: S12': Based on the initial geometric parameters of the mesh reinforcement, construct the mesh curve CL on the reference surface, and construct the normal segment of the reference surface at the intersection of each mesh curve CL.

7. The additive manufacturing method for the lightweight non-rotating body section according to claim 6, characterized in that, S12' also includes: using each mesh curve CL and normal segment as the framework for the mesh reinforcement surface, and constructing each mesh reinforcement surface.

8. The additive manufacturing method for the lightweight non-rotating body section according to claim 7, characterized in that, S12' also includes: checking whether the mesh rib surface meets the additive manufacturing forming angle requirements; if not, iteratively optimizing the mesh rib surface until all mesh rib surfaces meet the additive manufacturing forming angle requirements.

9. The additive manufacturing method for a lightweight non-rotating body section according to any one of claims 1 to 8, characterized in that, The preprocessing described in step 2 includes slicing, conformal scan path planning, support structure generation, and support structure mechanical simulation.

10. The additive manufacturing method for a lightweight non-rotating body section according to any one of claims 1 to 8, characterized in that, In step S3, a laser selective melting process is used, and titanium alloy, aluminum alloy or high-temperature alloy powder is selected. During the printing process, a partitioned scanning strategy is adopted, and the laser power is controlled within the range of 250W-350W, and the scanning speed is controlled within the range of 1000mm / s-1500mm / s.

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