Metal thin material side type 3D printing system and method

Abstract

The invention discloses a metal thin material side type 3D printing system and method. The system comprises a cutting laser, a printing laser, a gas circulation part, a feeding part, a printing base table and a printing control part. Wherein the feeding part is specially designed to comprise an upper feeding roller and a lower receiving roller, the upper feeding roller and the lower receiving roller are arranged in the vertical direction, and the metal thin material is tightly wound between the two rollers and is fed and recycled along a vertical path. The cutting laser and the printing laser are arranged on the same side of the printing face of the metal thin material, and the printing platform is arranged on the other side of the printing face. The feeding roller and the receiving roller are vertically arranged, so that the metal thin materials are continuously conveyed and recycled in the vertical direction. By means of the gravity effect, metal liquid drops generated by laser melting in the printing process are effectively prevented from splashing and falling to the workpiece forming surface, so that the printing quality is remarkably improved, and the device is particularly suitable for printing (super) meter-scale large-breadth workpieces.

Description

Technical Field

[0001] The present invention relates to the technical field of laser 3D printing, and in particular to a metal thin material side-type 3D printing system and method. Background Art

[0002] Laser powder bed fusion (LPBF) is an important metal 3D printing technology. It uses a laser beam to melt metal powder and accumulate it layer by layer to form a three-dimensional entity. It can realize the integrated direct forming of complex structural metal components and has been applied in important fields such as aerospace, electronics, medical, oil and gas, etc. Since the raw materials used in LPBF are metal powder particles, during the printing process, the metal vapor jet at the bottom of the molten pool will entrain a large amount of metal powder to form spatter, which will directly deteriorate the forming quality when it falls on the forming layer. Although the LPBF equipment is designed with a circulating airflow blowing system, for (super) meter-level large-format LPBF equipment, the wind field uniformity deviation is large, the spatter is difficult to remove, the full-format quality consistency is poor, and the manufacturing risk is increased.

[0003] Many existing metal sheets are 0.04-0.2mm thick, almost reaching the thickness of each layer of LPBF powder. Therefore, there are some methods that successfully prepare the required workpieces by printing metal sheets layer by layer. For example, CN108080638A discloses a laser 3D printing forming system and forming method for amorphous alloy foil, and CN106964900A discloses a laminated manufacturing device and method for metal additive manufacturing. Both achieve the use of metal sheets for printing, avoiding the disadvantages of using metal powder splashing, and also reduce the printing cost because the price of metal sheets is lower than that of metal powder and the utilization rate of metal sheets is higher.

[0004] However, even when 3D printing is performed using thin metal materials, the interaction between the laser and the metal material will still produce metal vapor-induced melt splashes, which are more significant and difficult to remove in the (super) meter-scale large-format multi-laser printing process. It is necessary to provide a corresponding solution. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the present invention vertically arranges the feeding component of the metal sheet so that the molten metal splashes generated during laser printing fall under the action of the top-down airflow and gravity without affecting the forming surface. The formed workpiece has the advantage of good forming quality consistency.

[0006] In order to achieve the above-mentioned object, the present invention provides a metal thin material side-type 3D printing system, comprising a cutting laser, a printing laser, a feeding component, a printing base and a printing control component, wherein the feeding component comprises a receiving roller and a feeding roller, wherein the feeding roller is located at the upper end of the receiving roller in the vertical direction, and the metal thin material is wound around the feeding roller and the receiving roller and is tightened for vertical feeding and receiving; The cutting laser and the printing laser are arranged on one side of the printing surface of the metal sheet; The printing base is arranged on the other side of the printing surface of the metal sheet; The printing control component is used to slice the workpiece and control the cutting laser, printing laser, feeding component and printing base.

[0007] Furthermore, the printing base comprises a substrate, a slider and a horizontal guide rail; the slider is arranged on the horizontal guide rail and connected to the substrate, and is used to control the workpiece on the substrate to move away from or close to the metal sheet.

[0008] Furthermore, a gas circulation component is provided parallel to the metal sheet, and the gas circulation component can generate a protective gas flow parallel to the metal sheet from top to bottom, which is used to purge the molten liquid generated by the printing laser and remove the splashes; The speed of the protective gas flow is 0.3-1m / s.

[0009] Furthermore, it also includes a printing cavity, wherein the feeding component and the printing base are arranged inside the printing cavity; The gas circulation component is fixed on the printing chamber; The printing cavity is filled with protective gas.

[0010] Furthermore, a recovery cabin is also provided in the printing chamber for collecting fallen splashes and serving as a return air device for protecting the airflow; the recovery cabin is located at the lower end of the metal sheet.

[0011] 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 thin material through the protective mirror.

[0012] The present invention also provides a method for printing using the above-mentioned metal thin material side 3D printing system, comprising: Use the printing control component to slice the workpiece and obtain the printing contour information; The feeding component delivers the metal sheet to the processing station, the printing laser prints it, and then the cutting laser cuts and separates it, and the printing of the workpiece is completed in this cycle.

[0013] Furthermore, the thickness of the metal thin material is 100-200 μm.

[0014] In the present invention, the protective gas filled in the printing cavity and the protective gas purged by the blowing component can prevent the thin material from being oxidized and forming defects during laser printing and laser cutting. The protective gas filled in the printing cavity and the protective gas generated by the blowing component are rare gases, preferably argon or helium.

[0015] The present invention also provides the application of the above-mentioned metal thin material side 3D printing system in the printing of meter-scale workpieces or super-meter-scale workpieces.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The present invention specially designs the feeding component to include an upper feeding roller and a lower receiving roller, which are arranged in the vertical direction. The metal sheet is tightly wound between the two rollers and fed and recovered along the vertical path. The effect of gravity is utilized to effectively prevent the metal droplets generated by laser melting from splashing and falling onto the workpiece forming surface during the printing process, thereby significantly improving the printing quality, which is particularly suitable for the printing of (super) meter-level large-format workpieces. At the same time, for the current meter-level LPBF printing equipment, which is about 5-6 meters or even 7-8 meters in height, the present invention can make full use of the horizontal space, and the overall height of the printing system is about 2 meters.

[0017] The raw material for printing in the present invention is a metal thin material without powder particle splashing, which is beneficial to improving the forming quality. At the same time, the surplus material can be efficiently recycled, and the raw material utilization rate is close to 100%. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 The schematic diagram of the structure of the metal thin material side 3D printing system of the present invention is shown; Figure 2 A schematic diagram showing the use of the metal thin material side 3D printing system of the present invention to print 100 layers of a required workpiece; Figure 3 A schematic diagram showing the transfer of new material for layer 101 is shown; Figure 4 A schematic diagram of printing the 101st layer is shown; Description of reference numerals: 1. Printing chamber; 101. Protective mirror; 102. Gas circulation component; 2. Printing laser; 3. Cutting laser; 4. Feeding component; 401. Receiving roller; 402. Feeding roller; 5. Metal sheet; 501. Melt; 6. Printing base; 601. Base plate; 602. Slider; 603. Horizontal guide rail; 7. Formed part; 8. Recovery bin. DETAILED DESCRIPTION

[0020] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] The following will be combined with the specific embodiments of the present invention and the drawings of the specification to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] Example 1 like Figure 1As shown, a side-type 3D printing system for metal thin materials includes a printing control component, a printing chamber 1 with a protective mirror 101 on the side wall, a cutting laser, a printing laser, and a feeding component 4, a printing base 6 and a recovery bin 8 arranged inside the printing chamber 1. Among them, the feeding component 4 includes a receiving roller 401 and a feeding roller 402, and the feeding roller 402 is located at the upper end of the receiving roller 401 in the vertical direction. The metal thin material 5 is wound around the feeding roller 402 and the receiving roller 401 and is tightened for vertical feeding and receiving. The cutting laser and the printing laser are arranged on one side of the printing surface of the metal thin material 5 and are arranged outside the printing chamber 1. The cutting laser 3 and the printing laser 2 incident from the cutting laser and the printing laser act on the metal thin material 5 through the protective mirror 101. The printing base 6 is arranged on the other side of the printing surface of the metal sheet 5, and the printing base 6 includes a substrate 601, a slider 602, a servo motor and a horizontal guide rail 603; the slider 602 is arranged on the horizontal guide rail 603 and connected to the substrate 601, and the slider 602 can be driven by the servo motor to control the forming part 7 on the substrate 601 to move away from or close to the metal sheet 5. A gas circulation component 102 is also arranged at the top of the printing chamber 1, and the gas circulation component 102 is arranged parallel to the direction of the metal sheet 5. The gas circulation component 102 can generate an argon gas flow parallel to the metal sheet 5 from top to bottom, and the speed of the argon gas flow is 0.5m / s, which is used to purge the melt 501 generated by the printing laser 2 and take away the splashes. The recovery bin 8 is located at the lower end of the metal sheet 5, and is used to collect the fallen splashes and as a return air device for protecting the air flow. 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 base 6.

[0023] In this embodiment, two printing lasers 2 are provided, and one cutting laser is provided, and the two printing lasers are provided symmetrically to the cutting laser. Of course, the actual embodiment is not limited thereto, and the number of printing lasers can be set to 4, 6, 8, 10, 12, 16, etc. according to the printing format size.

[0024] In this embodiment, the printing chamber 1 is also connected to an argon tank to provide argon gas to the inside of the printing chamber 1 and the blowing component 102. The printing chamber 1 is filled with argon gas to prevent defects caused by oxidation of materials during laser printing and cutting. The height of the printing chamber is about 2m.

[0025] The centers of the receiving roller 401 and the feeding roller 402 are connected to the rotating shaft, and the direction and speed of the rotating shaft are controlled by a stepper motor. The rotating shaft is designed with a tension adjustment device, which accurately moves in the vertical direction by monitoring the tension force of the metal sheet 5, and performs necessary tensioning according to the actual printing situation to make the metal sheet 5 move smoothly.

[0026] Example 2 A method for 3D printing of a workpiece, based on the 3D printing system of embodiment 1, comprises the following steps: S1. Use the slicing software of the printing control component to slice the three-dimensional structure of the workpiece to obtain the contour information of each slice layer; and adjust the laser parameters of the cutting laser and the printing laser, the feeding speed of the receiving roller and the feeding roller for 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 component; S2, the receiving roller and the feeding roller rotate to send the metal sheet to the processing station, and the printing laser is used for printing, and then the cutting laser is used for cutting and separation, and the printing of the workpiece is completed in this cycle. Specifically, the printing process of the 100th and 101st layers of a workpiece is described as follows: 1. If Figure 2 As shown, the metal sheet can be divided into multiple partitions, such as ①②③④, where area ① is the residual material area formed by cutting after the 99th layer is printed, area ② is the processing area of ​​the 100th layer, and areas ③ and ④ are the new material areas of the 101st and 102nd layers respectively. At this time, the metal sheet is stationary, area ② becomes a processing station, the substrate is translated in the -X direction to the 99th layer forming surface of the workpiece and is flattened with the metal sheet, the printing laser prints the 100th layer of the workpiece, and the cutting laser separates the workpiece and the metal sheet according to the contour of the 100th layer. At this time, area ② is converted into the residual material area of ​​the 100th layer; 2. If Figure 3 As shown, after the 100th layer is processed, the substrate is translated 1-2 mm in the +X direction, and the thin material is moved one step in the -Z direction to transfer the 101st layer of new material area (area ③) to the processing station.

[0027] 3. If Figure 4 As shown, after area ③ reaches the processing station, the substrate is translated in the -X direction until the 100th layer forming surface of the part is flush with the metal sheet, and the 101st layer is printed.

[0028] In general, compared with other methods of printing with thin materials, the present invention sets the feed roller and the receiving roller in the vertical direction, and the metal thin materials wrapped around the feed roller and the receiving roller are also fed and received vertically, making use of gravity and the top-down airflow generated by the gas circulation component so that the molten splashes generated by the printing laser will not fall on the forming surface of the workpiece. For the thin material printing method with horizontal feeding, in the process of meter-level large-format printing, in order to blow away the splashes generated by the printing droplets, the airflow speed needs to reach 3m / s or even higher, and the defects caused to the workpiece cannot be avoided. The airflow speed of the present invention does not need to be very large, 0.5m / s is sufficient. In addition, by using the printing method of the present invention, the metal thin materials are collected on the receiving roller after printing, and can be recycled and re-smelted as a whole, and rolled to form new thin materials.

[0029] Finally, it should be noted that the above 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 aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A metal thin material side 3D printing system, comprising a cutting laser, a printing laser, a feeding component, a printing base and a printing control component, wherein the feeding component comprises a receiving roller and a feeding roller, characterized in that: The feeding roller is located at the upper end of the receiving roller in the vertical direction, and the metal sheet is wound around the feeding roller and the receiving roller and is tightened for vertical feeding and receiving; The cutting laser and the printing laser are arranged on one side of the printing surface of the metal sheet; The printing base is arranged on the other side of the printing surface of the metal sheet; The printing control component is used to slice the workpiece and control the cutting laser, printing laser, feeding component and printing base.

2. The metal thin material side 3D printing system according to claim 1, characterized in that: The printing base comprises a substrate, a slider and a horizontal guide rail; the slider is arranged on the horizontal guide rail and connected to the substrate, and is used to control the workpiece on the substrate to move away from or close to the metal sheet.

3. The metal thin material side-type 3D printing system according to claim 1, characterized in that: A gas circulation component is also arranged parallel to the metal sheet, and the gas circulation component can generate a protective gas flow parallel to the metal sheet from top to bottom, which is used to purge the melt generated by the printing laser and remove the splashes; The speed of the protective gas flow is 0.3-1m / s.

4. The metal thin material side 3D printing system according to claims 1-3, characterized in that: It also includes a printing cavity, wherein the feeding component and the printing base are arranged inside the printing cavity; The gas circulation component is fixed on the printing chamber; The printing cavity is filled with protective gas.

5. The metal thin material side-type 3D printing system according to claim 4, characterized in that: A recovery cabin is also provided in the printing chamber for collecting fallen splashes and serving as a return air device for protecting the air flow; the recovery cabin is located at the lower end of the metal sheet.

6. The metal thin material side-type 3D printing system according to claim 4, 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 thin material through the protective mirror.

7. A method for printing using the metal thin material side-type 3D printing system according to any one of claims 1 to 6, characterized in that: include, Use the printing control component to slice the workpiece and obtain the printing contour information; The feeding component delivers the metal sheet to the processing station, the printing laser prints it, and then the cutting laser cuts and separates it, and the printing of the workpiece is completed in this cycle.

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

9. Application of the metal thin material side-type 3D printing system according to any one of claims 1 to 6 in printing meter-scale workpieces or super-meter-scale workpieces.

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