A metal sheet side 3D printing system and method

Abstract

This invention discloses a side-mounted 3D printing system and method for thin metal sheets. The system includes a cutting laser, a printing laser, a gas circulation component, a feeding component, a printing platform, and a printing control component. The feeding component is specifically designed to include an upper feeding roller and a lower receiving roller, both arranged vertically. The thin metal sheet is tightly wound between these two rollers and fed and retrieved along a vertical path. The cutting laser and the printing laser are positioned on the same side of the metal sheet printing surface, while the printing platform is located on the other side. By arranging the feeding and receiving rollers vertically, the thin metal sheet is continuously transported and retrieved vertically. This invention utilizes gravity to effectively prevent molten metal droplets generated by laser melting from splashing onto the workpiece surface during printing, thereby significantly improving print quality, and is particularly suitable for printing large-format (ultra-meter) workpieces.

Description

Technical Field

[0001] This invention relates to the field of laser 3D printing technology, and in particular to a side-mounted 3D printing system and method for thin metal materials. Background Technology

[0002] Laser bed melting (LPBF) is an important metal 3D printing technology that uses a laser beam to melt metal powder and deposit it layer by layer to form a three-dimensional solid. It enables the direct, integrated forming of complex metal components and has been applied in important fields such as aerospace, electronics, medical, and oil and gas. However, because LPBF uses metal powder particles as raw material, during the printing process, the metal vapor jet at the bottom of the molten pool entrains a large amount of metal powder, forming spatter that falls onto the formed layer and directly degrades the quality of the finished product. Although LPBF equipment is designed with a circulating airflow removal system, for (ultra) meter-scale large-format LPBF equipment, the airflow uniformity is large, making spatter difficult to remove, resulting in poor overall quality consistency and increased manufacturing risks.

[0003] Many existing metal sheets have a thickness of 0.04-0.2 mm, which is almost the thickness of each layer of LPBF powder deposition. Therefore, some methods have successfully prepared the required workpieces by printing metal sheets layer by layer. For example, CN108080638A discloses a laser 3D printing system and method for amorphous alloy foil, and CN106964900A discloses a layer-by-layer manufacturing equipment and method for metal additive manufacturing. Both of these methods achieve printing using metal sheets, avoiding the drawbacks of metal powder splatter. Furthermore, the lower price of metal sheets compared to metal powder and their higher utilization rate reduce printing costs.

[0004] However, even when using thin metal sheets for 3D printing, the interaction between the laser and the metal material still produces molten metal induced splashing, which is more pronounced and difficult to remove during large-format multi-laser printing at the (ultra) meter level. Therefore, it is necessary to provide corresponding solutions. Summary of the Invention

[0005] To address the problems of existing technologies, this invention vertically positions the feeding component of the thin metal material, allowing the molten metal splashes generated during laser printing to fall off under the influence of the downward airflow and gravity, without affecting the forming surface. This results in workpieces with good consistency in forming quality.

[0006] To achieve the above objectives, the present invention provides a side-mounted 3D printing system for thin metal sheets, including a cutting laser, a printing laser, a feeding component, a printing base, and a printing control component. The feeding component includes a take-up roller and a feeding roller. The feeding roller is located at the upper vertical direction of the take-up roller. Thin metal sheets are wound around the feeding roller and the take-up roller and tightened for vertical feeding and take-up.

[0007] The cutting laser and the printing laser are disposed on one side of the printing surface of the metal sheet;

[0008] The printing base is located on the other side of the printing surface of the metal sheet;

[0009] The printing control unit is used to slice the workpiece and control the cutting laser, printing laser, feeding unit, and printing base.

[0010] Furthermore, the printing platform includes a substrate, a slider, and a horizontal guide rail; the slider is disposed on the horizontal guide rail and connected to the substrate, and is used to control the movement of the workpiece on the substrate away from or towards the thin metal material.

[0011] Furthermore, a gas circulation component is provided parallel to the metal sheet. The gas circulation component can generate a protective airflow parallel to the metal sheet from top to bottom to blow away the molten liquid generated by the printing laser and carry away the splashes.

[0012] The velocity of the protective gas flow is 0.3-1 m / s.

[0013] Furthermore, it also includes a printing cavity, wherein the feeding component and the printing base are disposed inside the printing cavity;

[0014] The gas circulation component is fixed to the printing cavity;

[0015] The printing cavity is filled with protective gas.

[0016] Furthermore, the printing cavity is also equipped with a recovery chamber for collecting fallen debris and a return air device for protecting the airflow; the recovery chamber is located at the lower end of the metal sheet.

[0017] Furthermore, a protective mirror is provided on one side of the printing cavity, and the lasers incident from the cutting laser and the printing laser act on the metal sheet after passing through the protective mirror.

[0018] This invention also provides a method for printing using the aforementioned side-mounted 3D printing system for thin metal sheets, including:

[0019] The workpiece is sliced ​​using the printing control unit to obtain the printing contour information;

[0020] The feeding component delivers the thin metal sheet to the processing station, where the printing laser prints it, and then the cutting laser cuts it apart. This cycle is repeated to complete the printing of the workpiece.

[0021] Furthermore, the thickness of the metal sheet is 100-200 μm.

[0022] In this invention, filling the printing cavity with a protective gas and using a blowing component to purge the gas prevents oxidation defects in thin materials during laser printing and laser cutting. The protective gas filling the printing cavity and the protective gas generated by the blowing component are rare gases, preferably argon or helium.

[0023] The present invention also provides the application of the above-mentioned metal thin-film side-type 3D printing system in the printing of meter-level or ultra-meter-level workpieces.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] This invention features a specially designed feeding component comprising an upper feeding roller and a lower receiving roller, both arranged vertically. The thin metal sheet is tightly wound between these two rollers and fed and retrieved along a vertical path. Utilizing gravity, this effectively prevents molten metal droplets generated by laser melting from splashing onto the workpiece surface during printing, thus significantly improving print quality. This is particularly suitable for printing large-format (ultra) meter-level workpieces. Furthermore, compared to the current height of approximately 5-6 meters, or even 7-8 meters, in meter-level LPBF printing equipment, this invention fully utilizes lateral space, resulting in an overall printing system height of approximately 2 meters.

[0026] The raw material used for printing in this invention is thin metal material, which does not cause powder particles to splash, thus improving the forming quality. At the same time, the leftover material can be efficiently recycled, and the raw material utilization rate is close to 100%. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 A schematic diagram of the structure of the metal thin-film side-type 3D printing system of the present invention is shown;

[0029] Figure 2 A schematic diagram is shown of printing a desired workpiece with 100 layers using the metal thin-film side-type 3D printing system of the present invention;

[0030] Figure 3 A schematic diagram of the transfer of new material in the 101st layer is shown;

[0031] Figure 4 A schematic diagram of the printing on layer 101 is shown;

[0032] Explanation of reference numerals in the attached figures:

[0033] 1. Printing cavity; 101. Protective mirror; 102. Gas circulation component; 2. Printing laser; 3. Cutting laser; 4. Feeding component; 401. Receiving roller; 402. Feeding roller; 5. Thin metal sheet; 501. Molten metal; 6. Printing base; 601. Substrate; 602. Slider; 603. Horizontal guide rail; 7. Formed part; 8. Recycling bin. Detailed Implementation

[0034] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, a direct connection, or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0035] The technical solutions of the present invention will be clearly and completely described below with reference to specific embodiments and accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] Example 1

[0037] like Figure 1As shown, a side-mounted 3D printing system for thin metal sheets includes a printing control unit, a printing cavity 1 with a protective mirror 101 on its sidewall, a cutting laser, a printing laser, and a feeding unit 4, a printing base 6, and a recovery chamber 8 disposed inside the printing cavity 1. The feeding unit 4 includes a receiving roller 401 and a feeding roller 402. The feeding roller 402 is located at the upper vertical direction of the receiving roller 401. The thin metal sheet 5 is wound around the feeding roller 402 and the receiving roller 401 and is tightened for vertical feeding and recovery. The cutting laser and the printing laser are disposed on one side of the printing surface of the thin metal sheet 5 and are located outside the printing cavity 1. The cutting laser 3 and the printing laser 2 incident from the cutting laser and the printing laser act on the thin metal sheet 5 through the protective mirror 101. A printing platform 6 is located on the other side of the printing surface of the metal sheet 5. The printing platform 6 includes a substrate 601, a slider 602, a servo motor, and a horizontal guide rail 603. The slider 602 is mounted on the horizontal guide rail 603 and connected to the substrate 601. The slider 602 can be driven by the servo motor to control the movement of the formed part 7 on the substrate 601 away from or near the metal sheet 5. A gas circulation component 102 is also provided at the top of the printing cavity 1. The gas circulation component 102 is arranged parallel to the direction of the metal sheet 5 and can generate an argon gas flow parallel to the metal sheet 5 from top to bottom. The argon gas flow velocity is 0.5 m / s, which is used to blow away the molten liquid 501 generated by the printing laser 2 and carry away the splashes. A recovery chamber 8 is located at the lower end of the metal sheet 5 and is used to collect the fallen splashes and serve as a return air device for protective airflow. The printing control component is used to slice the workpiece and control the cutting laser, the printing laser, the feeding component 4, and the printing platform 6.

[0038] In this embodiment, two printing lasers and one cutting laser are provided, with the two printing lasers symmetrically positioned to the cutting laser. However, this is not a limitation; the number of printing lasers can be adjusted to 4, 6, 8, 10, 12, 16, etc., depending on the printing area size.

[0039] In this embodiment, the printing cavity 1 is also connected to an argon gas tank, thereby providing argon gas to the interior of the printing cavity 1 and the blowing component 102. The printing cavity 1 is filled with argon gas to prevent material oxidation and defects during the laser printing and cutting process. The height of the printing cavity is approximately 2m.

[0040] The centers of the receiving roller 401 and the feeding roller 402 are connected to the rotating shaft, which is controlled by a stepper motor to adjust the direction and speed. The rotating shaft is designed with a tension adjustment device, which monitors the tension of the metal sheet 5 in the vertical direction to move it precisely, and adjusts the tension as necessary according to the actual printing situation to make the metal sheet 5 move smoothly.

[0041] Example 2

[0042] A method for 3D printing a workpiece, based on the 3D printing system of Embodiment 1, includes the following steps:

[0043] S1. Use the slicing software of the printing control unit to slice the three-dimensional structure of the workpiece and obtain the contour information of each slice layer; and adjust the laser parameters of the cutting laser and printing laser, the feeding speed of the take-up roller and the feeding roller on the metal sheet, the flow rate of the argon gas flow generated by the blowing component, and the movement parameters of the slider through the printing control unit.

[0044] S2. The take-up roller and feed roller rotate, feeding the thin metal sheet to the processing station. A printing laser prints the sheet, followed by a cutting laser separating it. This cycle repeats to complete the printing of the workpiece. The printing process for the 100th and 101st layers of a specific workpiece will be explained below:

[0045] 1. For example Figure 2 As shown, the thin metal sheet can be divided into multiple zones, such as zones ①②③④. Zone ① is the leftover material area formed after cutting away the material after 99 layers of printing, zone ② is the processing zone for the 100th layer, and zones ③ and ④ are the new material areas for the 101st and 102nd layers, respectively. At this time, the thin metal sheet is stationary, zone ② becomes the processing station, the substrate is translated in the -X direction until the 99th layer forming surface of the workpiece is flat against the thin metal sheet, the printing laser prints the 100th layer of the workpiece, and the cutting laser separates the workpiece from the thin metal sheet according to the contour of the 100th layer. At this time, zone ② becomes the leftover material area for the 100th layer.

[0046] 2. For example Figure 3 As shown, after the 100th layer is processed, the substrate is translated 1-2mm in the +X direction, and the thin material is moved one step in the -Z direction to transfer the new material area of ​​the 101st layer (area ③) to the processing station.

[0047] 3. For example Figure 4 As shown, after reaching the processing station in area ③, the substrate is translated in the -X direction until it is flat against the forming surface of the 100th layer of the part and the metal sheet, and the 101st layer is printed.

[0048] Overall, compared to other methods of printing with thin materials, this invention arranges the feed and take-up rollers vertically. The metal sheet wound around the feed and take-up rollers is also fed and taken up vertically. Utilizing gravity and a downward airflow generated by the gas circulation component, the molten metal splashes from the printing laser do not fall onto the workpiece's forming surface. For horizontally fed thin-sheet printing, during meter-scale large-format printing, the airflow velocity needs to reach 3 m / s or even higher to remove the splashes from the molten droplets, and this still cannot avoid defects to the workpiece. In contrast, the airflow velocity of this invention is much lower, only 0.5 m / s is required. Furthermore, using this printing method, the metal sheet is collected on the take-up roller after printing and can be recycled and remelted, then rolled to form new thin-sheet material.

[0049] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A side-mounted 3D printing system for thin metal sheets, comprising a cutting laser, a printing laser, a feeding component, a printing base, and a printing control component, wherein the feeding component includes a take-up roller and a feeding roller, characterized in that: The feeding roller is located at the upper vertical direction of the receiving roller, and the thin metal material is wrapped around the feeding roller and the receiving roller and tightened to feed and collect materials vertically. The cutting laser and the printing laser are disposed on one side of the printing surface of the metal sheet; The printing base is located on the other side of the printing surface of the metal sheet; The printing control unit is used to slice the workpiece and control the cutting laser, printing laser, feeding unit, and printing base. A gas circulation component is also provided parallel to the metal sheet. The gas circulation component can generate a laminar protective airflow parallel to the metal sheet from top to bottom, which is used to blow away the molten liquid generated by the printing laser and carry away the splash. The velocity of the laminar protective airflow is adjustable according to the size of the splash, and can range from 0.3 to 1 m / s; The metal thin-film side-type 3D printing system is used for printing meter-level or ultra-meter-level workpieces.

2. The metal thin-film side-mounted 3D printing system according to claim 1, characterized in that, The printing platform includes a substrate, a slider, and a horizontal guide rail; the slider is disposed on the horizontal guide rail and connected to the substrate, and is used to control the movement of the workpiece on the substrate away from or towards the thin metal material.

3. The metal thin-film side-mounted 3D printing system according to claim 1, characterized in that, It also includes a printing cavity, wherein the feeding component and the printing base are disposed inside the printing cavity; The gas circulation component is fixed to the printing cavity; The printing cavity is filled with protective gas.

4. The metal thin-film side-mounted 3D printing system according to claim 3, characterized in that, The printing cavity is also equipped with a recovery chamber for collecting fallen debris and a return air device for protecting the airflow; the recovery chamber is located at the lower end of the metal sheet.

5. The metal thin-film side-mounted 3D printing system according to claim 3, characterized in that, A protective mirror is provided on one side of the printing cavity, and the lasers incident from the cutting laser and the printing laser act on the metal sheet after passing through the protective mirror.

6. A method for printing metal thin film using the side-mounted 3D printing system as described in any one of claims 1-5, characterized in that, include, The workpiece is sliced ​​using the printing control unit to obtain the printing contour information; The feeding component delivers the thin metal sheet to the processing station, where the printing laser prints it, and then the cutting laser cuts it apart. This cycle is repeated to complete the printing of the workpiece.

7. The method according to claim 6, characterized in that, The thickness of the metal sheet is 100-200 μm.

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