Selective laser melting forming method for C-shaped plate part with mounting joint

Abstract

The invention relates to a selective laser melting forming method for a C-shaped plate part with a mounting joint, belongs to the field of titanium alloy additive manufacturing, and solves the problems of large deformation and low forming efficiency in the additive manufacturing process of a non-closed rotary structure with a free end in the prior art. The invention discloses a selective laser melting forming method for a C-shaped plate part with a mounting joint. The selective laser melting forming method comprises the following steps: S1, three-dimensional modeling; s2, a placing mode and a supporting structure are set, specifically, the two C-shaped plate parts are placed in a mirror image mode, a solid support is added between the two C-shaped plate parts for connection, and a mirror image symmetry structure is formed; s3, model processing; s4, selective laser melting forming; s5, powder cleaning; and S6, linear cutting is conducted, specifically, after the part and the base plate are separated through linear cutting, the two integrated C-shaped plates are divided into two independent C-shaped plates. And less-support, high-dimensional-precision and high-efficiency selective laser melting forming of C-shaped plate parts with complex structures is realized.

Description

Technical Field

[0001] The invention relates to the technical field of titanium alloy additive manufacturing, and in particular to a laser selective melting forming method for a C-shaped plate part with a mounting joint. Background Art

[0002] Selective laser melting (SLM) is a rapidly developing technology in additive manufacturing. Thanks to its high precision, it is widely used in aerospace, automotive, medical and other fields. Thin-walled and complex structures can be formed with less excess through SLM, thereby reducing material loss and shortening processing cycles.

[0003] In the fields of aerospace, automobiles, etc., there are many TA15 titanium alloy thin-walled complex C-shaped plate parts with mounting joints. Since they are not closed rotary structures, there are free ends that are easily deformed, and there is a large wall thickness difference between the mounting joint position and other areas. Therefore, there is a large risk of deformation when directly performing laser selective melting on the C-shaped plate parts. It is necessary to increase the support density to prevent deformation and sagging during the forming process.

[0004] At present, in order to reduce gravity deformation during the 3D printing process of C-shaped plate parts, they are usually placed parallel to the printing platform. The commonly used support method is grid or lattice structure support, which is difficult to remove after printing. In addition, due to the dense support, it will limit the design of the part structure and is not suitable for the forming process of complex structural parts. Summary of the invention

[0005] In view of the above analysis, an embodiment of the present invention aims to provide a laser selective melting forming method for C-shaped plate parts with mounting joints, so as to solve at least one of the problems of large deformation, low forming efficiency, high support material loss, etc. in the existing additive manufacturing process of C-shaped plate parts with complex structures.

[0006] The embodiment of the present invention provides a method for selective laser melting of a C-shaped plate-like part with a mounting joint, comprising the following steps:

[0007] S1. 3D modeling: Establish a model based on the outline of the C-shaped plate part;

[0008] S2. Set the placement mode and support structure: Place two C-shaped plate parts in a mirrored manner, and add a solid support connection between the two C-shaped plate parts to form a mirror-symmetrical structure;

[0009] S3, model processing: slicing the two C-shaped plate part models after setting the placement mode and the solid support;

[0010] S4, laser selective melting forming: the processed model is subjected to laser selective melting forming operation, wherein the laser selective melting forming operation is performed on the substrate, and two C-shaped plate parts and a supporting structure are integrally formed, wherein the process parameters of the supporting structure are the same as those of the part body;

[0011] S5. Powder cleaning: After the laser selective melting is completed, the C-shaped plate part and the substrate are removed from the equipment, the substrate is lifted, and the powder around the substrate and the part is cleaned;

[0012] S6, Wire cutting: After the wire cutting separates the parts from the substrate, the two integrated C-shaped plates are further divided into two independent C-shaped plates.

[0013] Specifically, in step S2, the C-shaped plate part includes a body, a mounting joint and a process chuck; the body is a flat plate structure, including two panels, 2 bottom surfaces and 2 side surfaces; the mounting joint is located on the body panel, and the process chuck is located on the side of the body.

[0014] It should be noted that, in step S2, the angle between the panel of the C-shaped plate part and the vertical direction is less than 45°; the mounting joint of the C-shaped plate part faces the symmetry axis of the mirror-symmetrical structure;

[0015] Specifically, the physical support includes 2 physical plate structures;

[0016] The solid plate structure comprises two isosceles trapezoidal plate surfaces, an upper bottom edge, a lower bottom edge and two side edges; the plate surface of the solid plate structure is perpendicular to the base plate; the lower bottom edge of the solid plate structure is connected to the base plate; the two side edges of the solid plate structure are respectively connected to the side panels of two C-shaped plate strip mounting joints and are coplanar;

[0017] The two solid plate structures and the two C-shaped plate parts form a prism structure without upper and lower bottom surfaces;

[0018] Preferably, the solid plate structure is provided with periodically arranged teardrop-shaped holes.

[0019] Furthermore, the support structure also includes a surface support, and the surface support is distributed at the lowest point of the part and the area that does not meet the self-forming requirements.

[0020] Exemplarily, the C-shaped plate part is formed by laser selective melting using TA15 titanium alloy powder, and the particle size range of the TA15 titanium alloy powder is 15 to 53 μm.

[0021] Specifically, in step S4, the laser selective melting forming process parameters are: laser power 160-200 W, scanning rate 600-1000 mm / s, scanning spacing 0.08-0.12 mm, and powder layer thickness 30-40 μm.

[0022] Furthermore, the deformation of the C-shaped plate during the laser selective melting forming process is controlled within ±1 mm.

[0023] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0024] 1. In view of the large-format, non-closed rotational structural characteristics of C-shaped plate parts containing mounting joints, the present invention places each part at an angle of less than 45° between the panel and the vertical direction, so that most areas of each C-shaped plate and the mounting joint meet the self-forming conditions. In order to ensure the structural strength and control the surface quality, two C-shaped plate parts are arranged in mirror symmetry and connected by a solid plate-like support structure, which increases the structural strength and stability and avoids deformation of parts during the printing process; improves the dimensional accuracy of the surface, and controls the deformation during the forming process within ±1mm; reduces the addition of a large number of supports, and only needs to add support structures to the lowest point of the workpiece and some areas that do not meet the self-forming conditions, thereby reducing the loss of support materials.

[0025] 2. The present invention adopts a display form in which two C-shaped plate parts are arranged in mirror symmetry and connected by a solid plate support, so that a single C-shaped plate part can be placed at an angle less than 45° with the vertical direction. Compared with the prior art in which plate parts are 3D printed and placed parallel to the printing platform, the forming area of ​​a single part is reduced by more than 25%, which greatly improves the utilization rate of the printing platform, thereby improving the forming efficiency.

[0026] 3. The present invention further reduces material loss by designing periodically arranged teardrop-shaped holes on the solid plate-like support structure connecting two C-shaped plate parts, without affecting the support strength.

[0027] 4. The present invention forms two C-shaped plates at one time. On the one hand, it reduces the addition of supporting structures and improves material utilization; on the other hand, it reduces the forming area of ​​a single C-shaped plate, enables the placement of more parts on the substrate, and improves the forming efficiency.

[0028] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0030] Figure 1It is a schematic diagram of the three-dimensional structure of a TA15 titanium alloy C-shaped plate part (excluding a process chuck) with a mounting joint in an embodiment of the present invention;

[0031] Figure 2 This is a front view of a TA15 titanium alloy C-shaped plate part with a mounting joint in an embodiment of the present invention;

[0032] Figure 3 It is a left view of a TA15 titanium alloy C-shaped plate part with a mounting joint in an embodiment of the present invention;

[0033] Figure 4 It is a schematic diagram of the three-dimensional structure of two TA15 titanium alloy C-shaped plate parts with mounting joints with added physical support in an embodiment of the present invention;

[0034] Figure 5 This is a front view of the structure of two TA15 titanium alloy C-shaped plate parts with mounting joints with added physical support in an embodiment of the present invention;

[0035] Figure 6 A yz-plane cross-sectional view of a structure of two TA15 titanium alloy C-shaped plates with mounting joints with added physical support in an embodiment of the present invention;

[0036] Figure 7 A top view of the structure of two TA15 titanium alloy C-shaped plate parts with mounting joints with added physical support in an embodiment of the present invention;

[0037] Figure 8 A partial cross-sectional view of the mounting joint portion of two TA15 titanium alloy C-shaped plate parts with mounting joints having added physical supports in an embodiment of the present invention;

[0038] Fig. 9 Schematic diagram of the structural coordinate system of a TA15 titanium alloy C-shaped plate part with a mounting joint in an embodiment of the present invention.

[0039] Reference numerals:

[0040] 1-Solid plate structural support connecting two C-shaped plates; 2-Solid support in the non-self-forming area of ​​the C-shaped plate; 201-Surface support in the non-self-forming area at the C-shaped plate machining process chuck; 202-Surface support in the non-self-forming area at the C-shaped plate mounting joint; 203-Surface support in the non-self-forming area at the lowest point of the C-shaped plate; 3-C-shaped plate machining process chuck; 4-Mounting joint; 5-C-shaped plate body; 501-C-shaped plate body panel; 502-C-shaped plate body bottom surface; 503-C-shaped plate body side. DETAILED DESCRIPTION

[0041] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0042] The C-shaped plate part forming process includes a main body 5, a mounting joint 4 and a process chuck 3; the main body is a flat plate structure, including two panels 501, two bottom surfaces 502 and two side surfaces 503; the mounting joint 4 is located on the main body panel 501, and the process chuck 3 is located on the side surface 503 of the main body.

[0043] The 3D printing process of C-shaped plate part panels usually requires the setting of dense solid supports, which will limit the design of complex structures such as installation joints and process chucks on the C-shaped plate part panels. In addition, since the panels are provided with suspended structures such as installation joints and process chucks that are easily deformed or drooped during the printing process, the geometric discontinuity of the solid supports will easily lead to stress concentration.

[0044] At present, in order to reduce gravity deformation during the 3D printing process of C-shaped plate parts, they are usually placed parallel to the printing platform, and the commonly used support method is grid or lattice structure support. When this method is used, the grid or lattice structure support is difficult to remove after printing, and because the support is dense, it will limit the design of the part structure, which is not suitable for the forming process of complex structural parts, especially the 3D printing of large-format C-shaped plate parts with mounting joints of the present invention.

[0045] Based on this, a specific embodiment of the present invention discloses a laser selective melting forming method for a C-shaped plate-like part with a mounting joint, comprising the following steps:

[0046] S1. 3D modeling: Establish a model based on the outline of the C-shaped plate part;

[0047] S2. Set the placement mode and support structure: Place two C-shaped plate parts in a mirrored manner, and add a solid support connection between the two C-shaped plate parts to form a mirror-symmetrical structure;

[0048] S3, model processing: slicing the two C-shaped plate part models after setting the placement mode and the solid support;

[0049] S4, laser selective melting forming: two C-shaped plate parts and a support structure are integrally formed on a substrate, wherein the process parameters of the support structure are the same as those of the part body;

[0050] S5. Powder cleaning: After the laser selective melting is completed, the C-shaped plate part and the substrate are removed from the equipment, the substrate is lifted, and the powder around the substrate and the part is cleaned;

[0051] S6, Wire cutting: After the parts are separated from the substrate by wire cutting, the two integrated C-shaped plates are divided into two independent C-shaped plates.

[0052] Compared with the method in the prior art of placing C-shaped plate parts parallel to the printing platform and using a grid or lattice structure support during 3D printing, the placement method and support scheme of the present invention reduces the forming area by more than 25%, improves the utilization rate of the printing platform and the forming efficiency, and the support structure is easy to remove, shortening the post-processing time.

[0053] Specifically, in step S2, the C-shaped plate part includes a body, a mounting joint and a process chuck; the body is a flat plate structure, including two panels, two bottom surfaces and two side surfaces; the mounting joint is located on the body panel, and the process chuck is located on the side of the body;

[0054] The installation joint is a rectangular cylinder structure, located at the center of the panel on one side of the body, and the four walls of the installation joint cylinder are perpendicular to the body panel;

[0055] The process chuck is a rectangular parallelepiped structure and is located on the side of the main body. The height direction of the process chuck rectangular parallelepiped is perpendicular to the main body panel.

[0056] The 3D printing process of C-shaped plate part panels usually requires the setting of dense solid supports; and because the panels are equipped with suspended structures such as mounting joints and process chucks that are easily deformed or drooped during the printing process, the geometric discontinuity of the solid supports leads to stress concentration.

[0057] It should be noted that, in step S2, the angle between the panel of the C-shaped plate part and the vertical direction is less than 45°; the mounting joint of the C-shaped plate part faces the symmetry axis of the mirror-symmetrical structure;

[0058] Specifically, the physical support includes 2 physical plate structures;

[0059] The solid plate structure comprises two isosceles trapezoidal plate surfaces, an upper bottom edge, a lower bottom edge and two side edges; the plate surface of the solid plate structure is perpendicular to the base plate; the lower bottom edge of the solid plate structure is connected to the base plate; the two side edges of the solid plate structure are respectively connected to the side panels of two C-shaped plate strip mounting joints and are coplanar;

[0060] The two solid plate structures and the two C-shaped plate parts form a prism structure without upper and lower bottom surfaces;

[0061] The symmetry of the prism structure helps to evenly distribute the load, reduce structural deformation, and increase structural stability.

[0062] The thickness of the solid plate structure is 2-5 mm, preferably 5 mm.

[0063] In order to take into account both printing self-forming and surface quality during the 3D printing process, plate parts are usually placed parallel to the printing platform in the prior art, with a large format area, resulting in low utilization of the printing platform.

[0064] The study found that if the angle between the panel of a C-shaped plate part and the vertical direction is less than 45°, the plate part can self-form along the vertical direction; if a single C-shaped plate part is placed at an angle that allows it to self-form along the vertical direction, the C-shaped plate panel will be easily deformed and the surface quality cannot be controlled. The surface quality can be improved through dense support, but the setting of dense support will limit the design of complex structures such as installation joints and process chucks on the panel of the C-shaped plate part.

[0065] In the present invention, two C-shaped plate parts are arranged in mirror symmetry, and the two are connected by a solid plate structure support to form a stable structure, thereby avoiding deformation of parts during the printing process, improving the dimensional accuracy of the molding surface, and controlling the deformation during the forming process within ±1mm; at the same time, compared with placing the parts parallel to the printing platform, the forming area of ​​a single part is reduced by more than 25%, which greatly improves the utilization rate of the printing platform and the forming efficiency;

[0066] Furthermore, when placed, the mounting joints of the two C-shaped plate parts face the symmetry axis of the mirror-symmetrical structure, which facilitates the arrangement of linear support structures at the joints and other very few areas where self-forming cannot be completed;

[0067] Specifically, in step S2, the support structure further includes a surface support, the surface support is distributed at the lowest point of the part and the area that does not meet the self-forming requirement, and the surface support structure is a thin plate extending downward from the support position to the printing platform substrate;

[0068] The lowest point of the part and the area that does not meet the self-forming requirements are identified during the model processing, and then the surface support structure is added;

[0069] The structural coordinate system of the C-shaped plate parts is: the direction parallel to the bottom surface of the C-shaped plate body is the x direction, the direction parallel to the side surface of the C-shaped plate body is the z direction, and the center line of the C-shaped plate mounting joint cylinder is the y direction;

[0070] In a possible design, the surface support position of the part on one side of the symmetry axis of the mirror structure that does not meet the self-forming area includes: the four sides of the xy direction plane of each process chuck facing the printing platform; the three sides of the xy direction plane of the mounting joint facing the printing platform that are not connected to the C-shaped plate body panel; the edge of the inner wall of the cylinder at one end of the mounting joint that is not connected to the C-shaped plate body panel and is away from the printing platform in the x direction; the surface support position of the part on the other side of the symmetry axis that does not meet the self-forming area is mirror-symmetrical to the above positions;

[0071] The surface support structure at the area that does not satisfy the self-forming region is a thin plate extending along the above-mentioned support position to the printing platform substrate; the thickness of the surface support thin plate is 2 to 5 mm, preferably 5 mm.

[0072] Preferably, the solid plate structure and parts do not satisfy the requirement that the surface support of the self-forming area is provided with periodically arranged teardrop-shaped holes;

[0073] The water drop-shaped hole has a tapered portion facing upward, a hole diameter of 5-8 mm, a major axis of 6-10 mm, a hole spacing of 15-20 mm, and an opening rate of 30-40%;

[0074] The setting of the teardrop-shaped hole does not affect the structural strength and is conducive to reducing the loss of supporting materials. Compared with round holes and square holes, local deformation is more likely to occur, thereby reducing stress concentration.

[0075] In a possible design, the teardrop-shaped hole has a diameter of 6 mm, a major axis of 7.3 mm, a hole spacing of 18 mm, and an opening ratio of 38.6%.

[0076] Preferably, in order to facilitate positioning and removal of the support structure, the surface-shaped support sheet connected to the mounting joint is provided with a row of circular holes at its support position, and the diameter of the circular holes is 1 to 2 mm.

[0077] Exemplarily, the C-shaped plate part is formed by laser selective melting using TA15 titanium alloy powder, and the particle size range of the TA15 titanium alloy powder is 15 to 53 μm.

[0078] Specifically, in step S4, the laser selective melting forming process parameters are: laser power 160-200 W, scanning rate 600-1000 mm / s, scanning spacing 0.08-0.12 mm, and powder layer thickness 30-40 μm.

[0079] In a possible design, the laser selective melting forming process parameters are: laser power 180W, scanning rate 800mm / s, scanning spacing 0.10mm, and powder layer thickness 30μm.

[0080] Furthermore, the deformation of the C-shaped plate during the laser selective melting forming process is controlled within ±1 mm.

[0081] A three-coordinate measuring machine is used to measure the external dimensions of the 3D printed C-shaped plate parts, and the dimensions are compared with the design model to evaluate the dimensional deviation. The placement method and support design of the present invention can control the deformation of the forming process within ±1mm.

[0082] The present invention places each C-shaped plate part at an angle of less than 45° between the panel and the vertical direction, and arranges two C-shaped plate parts in mirror symmetry and connects them through a solid plate-shaped support structure, thereby increasing the structural strength and stability, avoiding deformation of parts during the printing process; improving the dimensional accuracy of the molding surface, and controlling the deformation during the forming process to ±1mm; reducing the loss of support materials; and reducing the forming format area, thereby improving the forming efficiency;

[0083] Furthermore, by designing periodically arranged teardrop-shaped holes on the solid plate support structure connecting the two C-shaped plate parts, material loss is further reduced without affecting the support strength.

[0084] The design of the present invention is described below through specific embodiments.

[0085] Example 1

[0086] The steps of laser selective melting to form a C-shaped plate part in this embodiment are as follows:

[0087] S1. 3D modeling: Establish a model based on the outline of the C-shaped plate part;

[0088] The dimensions of each C-shaped plate body are 230mm×180mm×5mm (thickness), and the mounting joint is located in the center of one side panel;

[0089] S2. Set the placement method and support structure:

[0090] Place two C-shaped plate parts in a mirrored manner, with the angle between each C-shaped plate panel and the vertical direction being 45°, the minimum spacing between the two C-shaped plates being 10mm, and the spacing between the bottom edges being 310mm;

[0091] Add a solid support connection between the two C-shaped plate parts to form a mirror-symmetrical structure. The solid support thickness is 5mm, with a teardrop-shaped hole with a hole diameter of 6mm, a major axis of 7.3mm, a hole spacing of 18mm, and an opening rate of 38.6%;

[0092] S3, model processing: slicing the two C-shaped plate part models after setting the placement mode and the solid support;

[0093] S4, laser selective melting forming: the processed model is subjected to laser selective melting forming operation, wherein the laser selective melting forming operation is performed on the substrate, and two C-shaped plate parts and a supporting structure are integrally formed, wherein the process parameters of the supporting structure are the same as those of the part body;

[0094] The process parameters of laser selective melting are as follows: laser power 180W, scanning rate 800mm / s, scanning spacing 0.10mm, powder layer thickness 30μm;

[0095] S5. Powder cleaning: After the laser selective melting is completed, the C-shaped plate part and the substrate are removed from the equipment, the substrate is lifted, and the powder around the substrate and the part is cleaned;

[0096] S6, Wire cutting: After the wire cutting separates the parts from the substrate, the two integrated C-shaped plates are further divided into two independent C-shaped plates.

[0097] Compared with placing only a single C-shaped plate part at the same vertical angle, the support material is saved by 35%; compared with the same C-shaped plate parallel to the printing plane, the format area is saved by 29.3%; the deformation during the forming process is controlled within ±1mm.

[0098] In view of the large-format, non-closed rotational structural characteristics of C-shaped plate parts containing mounting joints, the present invention places each part at an angle of less than 45° between the panel and the vertical direction, so that most areas of each C-shaped plate and the mounting joint meet the self-forming conditions. In order to ensure the structural strength and control the surface quality, two C-shaped plate parts are arranged in mirror symmetry and connected by a solid plate-like support structure, which increases the structural strength and stability, avoids deformation of parts during the printing process, reduces the forming format area of ​​a single part by more than 25%, and greatly improves the utilization rate of the printing platform; improves the dimensional accuracy of the surface, and controls the deformation during the forming process within ±1mm; reduces the addition of a large number of supports, and only needs to add support structures to the lowest point of the workpiece and some areas that do not meet the self-forming conditions, thereby reducing the loss of support materials.

[0099] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A laser selective melting forming method for C-shaped plate parts with mounting joints, characterized in that: The steps include: S1. 3D modeling: Establish a model based on the outline of the C-shaped plate part; S2. Set the placement mode and support structure: Place two C-shaped plate parts in a mirrored manner, and add a solid support connection between the two C-shaped plate parts to form a mirror-symmetrical structure; S3, model processing: slicing the two C-shaped plate part models after setting the placement mode and the solid support; S4, laser selective melting forming: the processed model is subjected to laser selective melting forming operation, wherein the laser selective melting forming operation is performed on the substrate, and two C-shaped plate parts and a supporting structure are integrally formed, wherein the process parameters of the supporting structure are the same as those of the part body; S5. Powder cleaning: After the laser selective melting is completed, the C-shaped plate part and the substrate are removed from the equipment, the substrate is lifted, and the powder around the substrate and the part is cleaned; S6, Wire cutting: After the parts are separated from the substrate by wire cutting, the two integrated C-shaped plates are divided into two independent C-shaped plates.

2. The forming method according to claim 1, characterized in that: In step S2, the C-shaped plate part includes a body, a mounting joint and a process chuck; the body is a flat plate structure, including two panels, 2 bottom surfaces and 2 side surfaces; the mounting joint is located on the body panel, and the process chuck is located on the side of the body.

3. The forming method according to claim 2, characterized in that: In step S2, the angle between the C-shaped plate part panel and the vertical direction is less than 45°.

4. The forming method according to claim 2, characterized in that: In step S2, the mounting joint of the C-shaped plate part faces the symmetry axis of the mirror-symmetrical structure.

5. The forming method according to claim 1, characterized in that: In step S2, the physical support includes two physical plate structures; The two solid plate structures and the two C-shaped plate parts form a prism structure without upper and lower bottom surfaces.

6. The forming method according to claim 1, characterized in that: The solid plate structure is provided with periodically arranged teardrop-shaped holes.

7. The forming method according to claim 5, characterized in that: In step S2, the support structure further includes a surface support, and the surface support is distributed at the lowest point of the part and the area that does not meet the self-forming requirements.

8. The forming method according to claim 7, characterized in that: The C-shaped plate part is formed by laser selective melting using TA15 titanium alloy powder, and the particle size range of the TA15 titanium alloy powder is 15 to 53 μm.

9. The forming method according to claim 6, characterized in that: In step S4, the laser selective melting forming process parameters are: laser power 160-200W, scanning rate 600-1000mm / s, scanning spacing 0.08-0.12mm, powder layer thickness 30-40μm.

10. The forming method according to claim 1, characterized in that: The deformation of the C-shaped plate during the laser selective melting forming process is controlled within ±1 mm.

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