Bionic support structure for SLM formed titanium alloy thin-walled cylindrical part

Abstract

The application provides a SLM forming titanium alloy thin-walled cylinder part bionic support structure and belongs to the technical field of three-dimensional printing, which comprises a base plate, a cylinder part located above the base plate, a solid support located below the side surface of the cylinder part and above the base plate, the cylinder part being connected with the base plate through the solid support, and a bionic support located above the base plate, wherein the bionic support comprises a plurality of support edges, each support edge is connected with each other to form a planar honeycomb structure, the planar honeycomb structure is uniformly distributed around the center of the cylinder part, a plurality of layers of the planar honeycomb structure are stacked along the height direction of the cylinder part to form a three-dimensional honeycomb structure, and the three-dimensional honeycomb structure is connected with the cylinder part. The application has the beneficial effects of improving the printing precision of the part, effectively preventing stress cracking, being easy to remove, improving local heat accumulation and reducing material consumption.

Description

Technical Field

[0001] This invention belongs to the field of 3D printing technology and relates to a biomimetic support structure for SLM-molded thin-walled titanium alloy cylindrical parts. Background Technology

[0002] 3D printing is a technology that uses the principle of digital layer-by-layer manufacturing to print three-dimensional digital models into solid parts. Depending on the state of the materials used and the forming method, 3D printing technology can be divided into several methods, including Fused Deposition Modeling (FDM), Stereolithography (SLA), Digital Light Processing (DLP), Layered Object Manufacturing (LOM), Selective Electron Beam Melting (EBM), and Selective Laser Melting (SLM).

[0003] Selective Laser Melting (SLM) technology, based on the "discrete-stacking" additive manufacturing concept, can directly form complex structural parts such as lattice sandwich panels, irregular curved surfaces, and internal cavity channels. It utilizes specialized 3D software to slice and layer the model to obtain cross-sectional information, which is then input into a printing device. The solid part is ultimately formed by layering materials. This method requires no tooling or molds, is virtually unrestricted by the complexity of the part, and offers high forming accuracy, short cycle time, and stable part quality and performance. It has broad application prospects in aerospace, biomedicine, automotive manufacturing, and industrial production.

[0004] Titanium alloys are extremely difficult to manufacture due to their high melting point, high activity, low thermal conductivity, and high resistance to deformation. This is especially true for complex aerospace structures, where traditional manufacturing methods result in numerous steps, long lead times, high costs, and low yields. Aerospace titanium alloy parts are trending towards functionalization, lightweighting, increased complexity, and integrated structures. Traditional manufacturing technologies are increasingly unable to meet these demands.

[0005] SLM technology possesses superior capabilities for forming complex structures, providing a low-cost and high-efficiency method for forming aerospace titanium alloy parts. However, during the SLM forming of thin-walled cylindrical parts made of titanium alloy, the rapid heating of the molten pool leads to a large temperature difference with the surrounding environment, causing stress cracking due to rapid heating and cooling, difficulty in removing support structures, local deformation caused by poor local heat dissipation, and high cost of support structures, which hinders its development. Therefore, there is considerable room for improvement. Summary of the Invention

[0006] The purpose of this invention is to address the aforementioned problems in the existing technology by proposing a biomimetic support structure for SLM-formed thin-walled titanium alloy cylindrical parts.

[0007] The objective of this invention can be achieved through the following technical solution: a biomimetic support structure for a thin-walled cylindrical titanium alloy part formed by SLM molding, characterized in that it comprises:

[0008] substrate;

[0009] A cylindrical component located above the substrate;

[0010] A solid support is located on the lower side of the cylindrical component and above the substrate, and the cylindrical component is connected to the substrate through the solid support.

[0011] A biomimetic support is located above the substrate. The biomimetic support includes several support ridges, which are connected to each other to form a planar honeycomb structure. The planar honeycomb structure is evenly distributed around the center of the cylindrical component. Several layers of the planar honeycomb structure are stacked along the height direction of the cylindrical component to form a three-dimensional honeycomb structure. The three-dimensional honeycomb structure is connected to the cylindrical component.

[0012] In the above-mentioned biomimetic support structure for a thin-walled cylindrical titanium alloy SLM forming titanium alloy, the biomimetic support also includes support columns, and the upper and lower adjacent planar honeycomb structures are connected by the support columns to form the three-dimensional honeycomb structure.

[0013] In the above-mentioned biomimetic support structure for a thin-walled cylindrical titanium alloy SLM-formed titanium alloy, there are also several gradient platforms. The gradient platforms are located above the substrate and are arranged sequentially from bottom to top. A three-dimensional honeycomb structure is provided between every two adjacent gradient platforms. The two adjacent gradient platforms are connected by the three-dimensional honeycomb structure. A three-dimensional honeycomb structure is provided between the bottom gradient platform and the substrate. The bottom gradient platform is connected to the substrate by the three-dimensional honeycomb structure.

[0014] In the above-mentioned biomimetic support structure for a thin-walled cylindrical titanium alloy SLM-formed component, the XY cross-sectional area of ​​the bottommost gradient platform does not exceed the XY cross-sectional area of ​​the substrate, and the XY cross-sectional area of ​​the upper gradient platform among two adjacent gradient platforms does not exceed the XY cross-sectional area of ​​the lower gradient platform.

[0015] In the above-mentioned biomimetic support structure for a thin-walled cylindrical titanium alloy SLM-formed component, the length of the support ridge of the upper three-dimensional honeycomb structure in two adjacent three-dimensional honeycomb structures does not exceed the length of the support ridge of the lower three-dimensional honeycomb structure, and the XY cross-sectional area of ​​the planar honeycomb structure of the upper three-dimensional honeycomb structure in two adjacent three-dimensional honeycomb structures does not exceed the XY cross-sectional area of ​​the planar honeycomb structure of the lower three-dimensional honeycomb structure.

[0016] In the above-mentioned biomimetic support structure for a thin-walled titanium alloy cylindrical part formed by SLM, there are also several key supports. The key supports are evenly distributed around the center of the cylindrical part. Each key support includes several serrations. The narrower end of each serration is connected to the cylindrical part. The three-dimensional honeycomb structure is connected to the serrations. Each serration is arranged sequentially from bottom to top.

[0017] In the above-mentioned biomimetic support structure for a thin-walled titanium alloy cylindrical part formed by SLM, the key support also includes fins, and the wider end of the serration is connected to the fin support. The fin is connected to the cylindrical part through the serration.

[0018] In the above-mentioned biomimetic support structure for a thin-walled cylindrical titanium alloy SLM forming titanium alloy, the interval between two adjacent saw teeth is 1mm-2mm, the inclination angle of the saw teeth is 30°-45°, the thickness of the fins is 0.5mm-2mm, and the width of the fins is 1mm-5mm.

[0019] In the above-mentioned biomimetic support structure for a thin-walled titanium alloy cylindrical part formed by SLM, the solid support includes several arc units, which are evenly distributed around the center of the cylindrical part.

[0020] In the above-mentioned biomimetic support structure for a thin-walled cylindrical titanium alloy SLM forming titanium alloy, the thickness of the arc unit is 2mm-3mm, the inner diameter of the arc unit is the same as the inner diameter of the cylindrical part, the outer diameter of the arc unit is the same as the outer diameter of the cylindrical part, and the arc unit increases in size as the height and diameter of the cylindrical part increase.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] 1. The three-dimensional honeycomb structure composed of hexagonal units reduces the deformation of thin-walled cylindrical parts due to their own stress during the SLM molding process, thereby maintaining the formability of the parts, improving the printing accuracy of the parts, effectively preventing stress cracking, making them easy to remove, improving local heat accumulation, and reducing material consumption.

[0023] 2. A gradient platform is established between each three-dimensional honeycomb structure, which can adapt to the changes in the upper and lower three-dimensional honeycomb structures, further effectively preventing stress cracking, facilitating removal, improving local heat accumulation, and reducing material consumption.

[0024] 3. As the height of the cylindrical component increases, the XY cross-sectional area of ​​the planar honeycomb structure decreases until it completely fits the outer wall of the cylindrical component. This adapts to the different stresses at different heights of the cylindrical component and makes it easier to remove, reducing material consumption.

[0025] 4. For locations where the residual stress of the cylindrical component exceeds a set threshold, serrations are set. The narrower end of the serration is connected to the cylindrical component, which effectively prevents stress cracking and is easy to remove. The three-dimensional honeycomb structure is connected to the serrations, making the three-dimensional honeycomb structure more stable.

[0026] 5. Fins are used for heat dissipation to improve local heat accumulation. At the same time, for cylindrical parts with large residual stress, the fins can be connected to the cylindrical parts through serrations to effectively prevent stress cracking. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the biomimetic support structure for the SLM-formed titanium alloy thin-walled cylindrical part of the present invention.

[0028] Figure 2 This is a front view of the biomimetic support structure for the SLM-formed titanium alloy thin-walled cylindrical part of the present invention.

[0029] Figure 3 This is a top view of the biomimetic support structure for the SLM-formed titanium alloy thin-walled cylindrical part of the present invention.

[0030] Figure 4 for Figure 3 A cross-sectional view from the perspective of AA.

[0031] Figure 5 This is a schematic diagram of the three-dimensional honeycomb structure of the present invention.

[0032] Figure 6 This is a schematic diagram of the planar honeycomb structure of the present invention.

[0033] Figure 7 This is a schematic diagram of the stress distribution of the cylindrical component of the present invention.

[0034] Figure 8 This is a schematic diagram showing the residual stress and allowable stress of the cylindrical component of the present invention.

[0035] In the diagram, 100 is the substrate; 200 is the cylindrical component; 300 is the solid support; 310 is the arc unit; 400 is the biomimetic support; 410 is the three-dimensional honeycomb structure; 411 is the planar honeycomb structure; 4111 is the support ridge; 412 is the support column; 500 is the gradient platform; 600 is the key support; 610 is the serration; and 620 is the fin. Detailed Implementation

[0036] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings to further illustrate the technical solutions of the present invention. However, the present invention is not limited to these embodiments.

[0037] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0038] Furthermore, in this invention, descriptions involving terms such as "first," "second," and "a" are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0039] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0040] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0041] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

[0042] like Figures 1-8 As shown, a biomimetic support structure for a thin-walled cylindrical titanium alloy part formed by SLM includes: a substrate 100, a cylindrical part 200, a solid support 300, and a biomimetic support 400.

[0043] The cylindrical component 200 is located above the substrate 100.

[0044] The solid support 300 is located on the lower side of the cylindrical component 200 and above the substrate 100, and the cylindrical component 200 is connected to the substrate 100 through the solid support 300.

[0045] The biomimetic support 400 is located above the substrate 100. The biomimetic support 400 includes a plurality of support ridges 4111, which are connected to each other to form a planar honeycomb structure 411. The planar honeycomb structure 411 is evenly distributed around the center of the cylindrical member 200. Several layers of the planar honeycomb structure 411 are stacked along the height direction of the cylindrical member 200 to form a three-dimensional honeycomb structure 410. The three-dimensional honeycomb structure 410 is connected to the cylindrical member 200.

[0046] Specifically, the planar honeycomb structure 411 is a structure with multiple hollow hexagonal units.

[0047] In this embodiment, a three-dimensional honeycomb structure 410 composed of hexagonal units is used to reduce the deformation of thin-walled cylindrical parts due to their own stress during the SLM molding process, thereby maintaining the formability of the parts, improving the printing accuracy of the parts, effectively preventing stress cracking, making them easy to remove, improving local heat accumulation, and reducing material consumption.

[0048] Based on the above embodiments, the biomimetic support 400 further includes a support column 412, and the two adjacent planar honeycomb structures 411 are connected by the support column 412 to form the three-dimensional honeycomb structure 410.

[0049] In this embodiment, the two adjacent planar honeycomb structures 411 are connected by support columns 412. The diameter of the support columns 412 is 0.4mm-0.5mm. The bottom and top of the support columns 412 are connected to the vertices of the hexagons on the planar honeycomb structure 411 by rib-shaped arc transitions, with the angle ranging from 120° to 150°.

[0050] Based on the above embodiments, a plurality of gradient platforms 500 are also included. The gradient platforms 500 are located above the substrate 100. Each gradient platform 500 is arranged sequentially from bottom to top. A three-dimensional honeycomb structure 410 is provided between each two adjacent gradient platforms 500. The two adjacent gradient platforms 500 are connected by the three-dimensional honeycomb structure 410. A three-dimensional honeycomb structure 410 is provided between the bottom gradient platform 500 and the substrate 100. The bottom gradient platform 500 is connected to the substrate 100 by the three-dimensional honeycomb structure 410.

[0051] In this embodiment, a gradient platform 500 is established between each three-dimensional honeycomb structure 410, which can adapt to the changes in the upper and lower three-dimensional honeycomb structures 410, further effectively preventing stress cracking, facilitating removal, improving local heat accumulation, and reducing material consumption.

[0052] Based on the above implementation, the XY cross-sectional area of ​​the bottommost gradient platform 500 does not exceed the XY cross-sectional area of ​​the substrate 100, and the XY cross-sectional area of ​​the upper gradient platform 500 among two adjacent gradient platforms 500 does not exceed the XY cross-sectional area of ​​the lower gradient platform 500.

[0053] In this embodiment, as the height of the cylindrical component 200 increases, the XY cross-sectional area of ​​the gradient platform 500 decreases, thereby adapting to different stresses at different heights of the cylindrical component 200 and making it easier to remove stresses, thus reducing material consumption.

[0054] Based on the above embodiments, the length of the support ridge 4111 of the upper three-dimensional honeycomb structure 410 in two adjacent three-dimensional honeycomb structures 410 does not exceed the length of the support ridge 4111 of the lower three-dimensional honeycomb structure 410, and the XY cross-sectional area of ​​the planar honeycomb structure 411 of the upper three-dimensional honeycomb structure 410 in two adjacent three-dimensional honeycomb structures 410 does not exceed the XY cross-sectional area of ​​the planar honeycomb structure 411 of the lower three-dimensional honeycomb structure 410.

[0055] In this embodiment, as the height of the cylindrical component 200 increases, the cross-sectional area of ​​the planar honeycomb structure 411XY becomes smaller, until it finally completely fits the outer wall of the cylindrical component 200, thereby adapting to the different stresses at different height positions of the cylindrical component 200, and making it easier to remove and reducing material consumption.

[0056] Based on the above implementation method, it also includes several key supports 600, which are evenly distributed around the center of the cylindrical component 200. Each key support 600 includes several serrations 610, the narrower end of each serration 610 is connected to the cylindrical component 200, and the three-dimensional honeycomb structure 410 is connected to the serrations 610. Each serration 610 is arranged sequentially from bottom to top.

[0057] In this embodiment, serrations 610 are provided at the locations where the residual stress of the cylindrical component 200 is greater than a set threshold. The narrower end of the serration 610 is connected to the cylindrical component 200, which effectively prevents stress cracking and is easy to remove. The three-dimensional honeycomb structure 410 is connected to the serrations 610, making the three-dimensional honeycomb structure 410 more stable.

[0058] Preferably, the interval between two adjacent saw teeth 610 is 1mm-2mm, and the inclination angle of the saw teeth 610 is 30°-45°.

[0059] Based on the above embodiments, the key support 600 also includes a fin 620, the wider end of the serration 610 is supported and connected to the fin 620, and the fin 620 is connected to the cylindrical component 200 through the serration 610.

[0060] In this embodiment, the fins 620 are used for heat dissipation to improve local heat accumulation. At the same time, for locations where the residual stress of the cylindrical component 200 is large, the fins 620 can be connected to the cylindrical component 200 through the serrations 610 to effectively prevent stress cracking.

[0061] Preferably, the thickness of the fin 620 is 0.5mm-2mm, and the width of the fin 620 is 1mm-5mm.

[0062] Based on the above embodiments, the solid support 300 includes a plurality of arc units 310, which are evenly distributed around the center of the cylindrical component 200, and the arc units 310 are easy to remove.

[0063] Preferably, the thickness of the arc unit 310 is 2mm-3mm, the inner diameter of the arc unit 310 is the same as the inner diameter of the cylindrical part 200, the outer diameter of the arc unit 310 is the same as the outer diameter of the cylindrical part 200, and the arc unit 310 increases in size as the height and diameter of the cylindrical part 200 increase.

[0064] Preferably, the included angle between two adjacent arc units 310 is 15-45°, and the thickness of the arc unit 310 is 2mm-3mm.

[0065] Taking the actual printing process as an example, firstly, a solid support 300 composed of arc units 310 is printed on the substrate 100. The solid support 300 includes a bottom surface and a top surface. The thickness of the solid support 300 is 2mm-3mm. The bottom surface is a trapezoid with the height and diameter of the cylindrical workpiece increasing accordingly as needed. The included angle between the arc units 310 is 15°-45°. Then, a gradient platform 500 with a thickness of 3mm-5mm is printed on the top surface of the solid support 300. The XY cross-sectional area of ​​the gradient platform 500 increases with the height and diameter of the cylindrical workpiece 200. Then, on this gradient platform 500... Starting from 00, a three-dimensional honeycomb structure 410 is constructed around the outer wall of the cylindrical component 200. The three-dimensional honeycomb structure 410 consists of a planar honeycomb structure 411 and supporting columns 412. The height between adjacent layers of the planar honeycomb structure 411 from the first to the third layer is 5mm-15mm. The length of the supporting edge 4111 is consistent with the height of the layer it belongs to (5mm-15mm), and the diameter of the supporting edge 4111 is 0.3mm-2mm. 10-50 hexagons are constructed on one side of the cylindrical component 200 on the XY plane. The XY cross-sectional area of ​​the planar honeycomb structure 411 does not exceed 5 of this gradient platform. The cross-sectional area of ​​the 00XY section is as follows: the diameter of the support column 412 is 0.4mm-0.5mm; the bottom and top of the support column 412 are connected to the vertices of the hexagons on the planar honeycomb structure 411 by rib-shaped arc transitions, with an angle in the range of 120°-150°; then, another gradient platform 500 with a thickness of 0.5mm-2mm is printed. On this gradient platform 500, a three-dimensional honeycomb structure 410 with 1-3 fewer hexagons than the three-dimensional honeycomb structure 410 on the previous gradient platform 500 is built, thus completing the printing of the 4th to 6th layers; and so on, as the height of the cylindrical part 200 increases... The position changes, continuously reducing the number of supports and the size of the hexagons until they are completely fitted to the outer wall of the cylinder; in addition, during printing, serrations 610 are set at the positions where the residual stress of the cylindrical part 200 feature exceeds the set threshold. The narrower end of the serration 610 is integrated with the cylinder and the contact width between the two is 0.2mm-0.6mm. The interval between two adjacent serrations 610 is 1mm-2mm. The tilt angle of the serration 610 is 30°-45°. Fins 620 are set for heat dissipation. The thickness of the fins 620 is 0.5mm-2mm and the width of the fins 620 is 1mm-5mm.

Claims

1. A biomimetic support structure for a thin-walled cylindrical titanium alloy part formed by SLM molding, characterized in that, include: substrate; A cylindrical component located above the substrate; A solid support is located on the lower side of the cylindrical component and above the substrate, and the cylindrical component is connected to the substrate through the solid support. A biomimetic support is located above the substrate. The biomimetic support includes several support ridges, which are connected to each other to form a planar honeycomb structure. The planar honeycomb structure is evenly distributed around the center of the cylindrical component. Several layers of the planar honeycomb structure are stacked along the height direction of the cylindrical component to form a three-dimensional honeycomb structure. The three-dimensional honeycomb structure is connected to the cylindrical component. The biomimetic support also includes support columns, and the upper and lower adjacent planar honeycomb structures are connected by the support columns to form the three-dimensional honeycomb structure. It also includes several gradient platforms, which are located above the substrate. The gradient platforms are arranged sequentially from bottom to top. A three-dimensional honeycomb structure is provided between each pair of adjacent gradient platforms. The two pairs of adjacent gradient platforms are connected by the three-dimensional honeycomb structure. A three-dimensional honeycomb structure is provided between the bottom gradient platform and the substrate. The bottom gradient platform is connected to the substrate by the three-dimensional honeycomb structure. The XY cross-sectional area of ​​the bottommost gradient platform does not exceed the XY cross-sectional area of ​​the substrate, and the XY cross-sectional area of ​​the upper gradient platform in two adjacent gradient platforms does not exceed the XY cross-sectional area of ​​the lower gradient platform. In two adjacent three-dimensional honeycomb structures, the length of the supporting edge of the upper three-dimensional honeycomb structure does not exceed the length of the supporting edge of the lower three-dimensional honeycomb structure, and the XY cross-sectional area of ​​the planar honeycomb structure of the upper three-dimensional honeycomb structure does not exceed the XY cross-sectional area of ​​the planar honeycomb structure of the lower three-dimensional honeycomb structure. It also includes several key supports, which are evenly distributed around the center of the cylindrical component. Each key support includes several serrations, with the narrower end of each serration connected to the cylindrical component. The three-dimensional honeycomb structure is connected to the serrations, and each serration is arranged sequentially from bottom to top. The key support also includes fins, with the wider end of the serrations connected to the fin support, and the fins connected to the cylindrical component via the serrations.

2. The biomimetic support structure for a thin-walled titanium alloy cylindrical part formed by SLM as described in claim 1, characterized in that: The interval between two adjacent serrations is 1mm-2mm, the inclination angle of the serrations is 30°-45°, the thickness of the fin is 0.5mm-2mm, and the width of the fin is 1mm-5mm.

3. The biomimetic support structure for a thin-walled titanium alloy cylindrical part formed by SLM as described in claim 1, characterized in that: The solid support includes several arc units, which are evenly distributed around the center of the cylindrical component.

4. The biomimetic support structure for a thin-walled titanium alloy cylindrical part formed by SLM as described in claim 3, characterized in that: The thickness of the arc unit is 2mm-3mm. The inner diameter of the arc unit is the same as the inner diameter of the cylindrical part, and the outer diameter of the arc unit is the same as the outer diameter of the cylindrical part. The arc unit increases in size as the height and diameter of the cylindrical part increase.

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