Method for improving surface precision of laser wire deposition build parts with femtosecond synchronization subtractive

Abstract

The application provides a method for improving the surface precision of a laser wire deposition component by femtosecond synchronization subtraction, comprising the following steps: S1, setting a double heat source, wherein the double heat source comprises a continuous laser and a femtosecond pulse laser; S2, establishing a three-dimensional geometric model of the additive manufacturing component by using computer-aided design software, and layering and slicing the three-dimensional geometric model by using slicing software; S3, discretizing the three-dimensional geometric model into two-dimensional contour data, and planning a scanning path of the continuous laser and a cutting path of the femtosecond pulse laser; S4, setting printing parameters of the continuous laser welding gun and cutting parameters of the femtosecond pulse laser welding gun; S5, according to the printing parameters of the continuous laser welding gun, depositing a metal wire according to the scanning path, and simultaneously, according to the cutting path, subtractively processing the surface of the additive manufacturing component by using the femtosecond pulse laser welding gun; and S6, repeating steps S4-S5 to complete layer-by-layer accumulation of the additive manufacturing component until a three-dimensional solid component is obtained.

Description

Technical Field

[0001] This invention relates to the field of additive manufacturing technology for metallic materials, and in particular to a method for improving the surface accuracy of laser filament deposition components by femtosecond synchronous subtractive manufacturing. Background Technology

[0002] Additive manufacturing technology, with its advantages of high design freedom, high R&D efficiency, fewer assembly steps, shorter product development cycles, and high raw material utilization, has significantly changed processing efficiency, cost, and production cycle, attracting widespread attention from the industry. Compared with traditional casting or forging processes, metal parts produced using additive manufacturing technology have extremely high hardness and yield strength, and are therefore widely used in aerospace, medical, and energy fields.

[0003] For metallic materials, additive manufacturing technology can be mainly divided into laser additive manufacturing, arc additive manufacturing, and electron beam additive manufacturing, depending on the high-energy beam heat source used. The differences in high-energy beam heat sources lead to variations in forming accuracy, deposition efficiency, and sensitivity to complex parts in high-energy beam micro-area melting additive manufacturing technology. The geometric accuracy and surface quality of additively manufactured parts often fail to meet the application requirements of high-performance metal parts, necessitating post-processing to obtain additively manufactured parts with higher surface quality. Subtractive manufacturing, including finishing, grinding, milling, laser polishing, abrasive flow polishing, and electrochemical polishing, can effectively improve the surface finish and mechanical properties of additively manufactured parts, and is currently the main method for surface treatment of additively manufactured parts.

[0004] The existing invention patent application with publication number CN112372142A proposes a femtosecond laser cleaning method for 3D printed metal surfaces. It uses a combination of femtosecond pulsed laser and scanning galvanometer system to clean the complex surface of metal components obtained by 3D printing, thereby reducing the surface roughness and improving the surface quality.

[0005] However, due to limited tooling accessibility, complex additive manufacturing part structures pose a challenge to traditional subtractive manufacturing techniques, and are even difficult to process using a single subtractive manufacturing method. Furthermore, post-processing inevitably leads to increased production steps and costs. Therefore, further exploration and improvement of subtractive manufacturing technologies to better serve the surface finishing needs of additive manufacturing are crucial. Summary of the Invention

[0006] In view of this, the present invention proposes a method for improving the surface accuracy of laser filament deposition components by femtosecond synchronous subtractive manufacturing. It uses dual heat sources for metal wire filament deposition and surface treatment, uses slicing software to determine the scanning path of continuous laser, and uses a path planning algorithm to determine the cutting path of femtosecond pulse laser, thereby achieving efficient and high-precision additive manufacturing.

[0007] The technical solution of this invention is implemented as follows:

[0008] In a first aspect, the present invention provides a method for improving the surface accuracy of laser filament-deposited components by femtosecond synchronous subtractive manufacturing, comprising the following steps:

[0009] S1. Set up dual heat sources, wherein the dual heat sources include continuous laser and femtosecond pulsed laser;

[0010] S2. Use computer-aided design software to create a three-dimensional geometric model of the additive manufacturing component, and use slicing software to slice the three-dimensional geometric model into layers.

[0011] S3. Discretize the three-dimensional geometric model into two-dimensional contour data, and plan the scanning path of the continuous laser and the cutting path of the femtosecond pulse laser.

[0012] S4. Set the printing parameters of the continuous laser welding gun and the cutting parameters of the femtosecond pulse laser welding gun;

[0013] S5. According to the printing parameters of the continuous laser welding gun, the metal wire is deposited according to the scanning path, and at the same time, the femtosecond pulsed laser welding gun performs subtractive processing on the surface of the additive manufacturing component according to the cutting path.

[0014] S6. Repeat steps S4-S5 to complete the layer-by-layer stacking of additive manufacturing components until a three-dimensional solid component is obtained.

[0015] Based on the above technical solutions, preferably, step S3 specifically includes:

[0016] S31. Discretize the three-dimensional geometric model into two-dimensional contour data;

[0017] S32. Based on the two-dimensional contour data, distinguish the inner contour region and the outer contour region of the polygonal contour obtained by slicing.

[0018] S33. Offset the outer contour outward and the inner contour inward;

[0019] S34. Use the offset contour as the cutting path of the femtosecond pulse laser.

[0020] Based on the above technical solutions, preferably, step S34 specifically includes:

[0021] S341. Use the offset contour as part of the cutting path to obtain a set of multiple offset paths with the same spacing.

[0022] S342. Calculate the femtosecond pulse laser cutting deviation on each cutting path in the bias path set;

[0023] S343. Compare the femtosecond pulse laser cutting deviation with a first set threshold. If the femtosecond pulse laser cutting deviation is greater than the first set threshold, adjust the cutting path.

[0024] S344, Output the optimized cutting path.

[0025] Based on the above technical solutions, preferably, step S343 specifically includes:

[0026] During laser cutting, record the theoretical width of the cross-section to be cut and the actual width of the cross-section already cut for each cut;

[0027] The theoretical width of the cross-section to be cut is compared with the actual width of the cut cross-section to calculate the femtosecond pulse laser cutting deviation.

[0028] The femtosecond pulse laser cutting deviation is compared with a first set threshold. If the femtosecond pulse laser cutting deviation is greater than the first set threshold, the cutting path is adjusted.

[0029] After the cutting path is adjusted, laser cutting is performed again until the femtosecond pulse laser cutting deviation is less than the first set threshold.

[0030] Based on the above technical solutions, preferably, step S33 specifically includes:

[0031] Use the offset tool to offset outwards by a specified distance at each point of the outer contour to generate a new outer contour;

[0032] Use the offset tool to offset inward by a specified distance at each point of the inner contour to generate a new inner contour;

[0033] The offset distances of the outer and inner contours are adjusted to obtain the new dimensions and shapes of the outer and inner contours.

[0034] Based on the above technical solutions, preferably, step S5 specifically includes:

[0035] Using the continuous laser welding gun, molten wire is deposited along the cutting path;

[0036] Based on the shape and surface precision requirements of the additively manufactured components, the cutting path of the femtosecond pulsed laser welding gun is planned;

[0037] The inner and outer surfaces of additively manufactured components are processed using a femtosecond pulsed laser welding torch.

[0038] Based on the above technical solutions, preferably, the femtosecond pulsed laser welding gun has a wavelength of 1000-1050nm, a pulse frequency of 10-1000kHz, and a power of 5-200W.

[0039] Based on the above technical solutions, preferably, the continuous laser welding gun has a laser power of 1000W to 10000W, a laser scanning speed of 10 to 15m / min, and a wire feeding speed of 10 to 20m / min.

[0040] Based on the above technical solutions, preferably, in step S6, during the layer-by-layer stacking process of the additive manufacturing component, an inert protective gas is introduced at an angle into the laser-material interaction region.

[0041] Secondly, the present invention provides a system for improving the surface accuracy of laser filament-deposited components by femtosecond synchronous subtractive manufacturing, employing the method described above, comprising:

[0042] The path planning module is used to discretize the three-dimensional geometric model of the additive manufacturing component created using computer-aided design software into two-dimensional contour data, and plan the scanning path of continuous laser and the cutting path of femtosecond pulse laser.

[0043] The parameter setting module is used to set the printing parameters of the continuous laser welding gun and the cutting parameters of the femtosecond pulse laser welding gun.

[0044] A continuous laser welding torch is used to deposit molten wire along a scanning path;

[0045] Femtosecond pulsed laser welding guns are used to perform subtractive processing on the surface of additively manufactured components.

[0046] The method for improving the surface accuracy of laser fused filament deposited components using femtosecond synchronous subtractive manufacturing of the present invention has the following advantages over the prior art:

[0047] (1) Synchronous subtraction is achieved by continuous laser additive manufacturing and femtosecond pulsed laser. The continuous laser is used for fused deposition of metal wires, and the femtosecond pulsed laser is used for surface subtraction. The scanning path of the continuous laser is determined by slicing software, and the cutting path of the femtosecond pulsed laser is determined by path planning algorithm. By planning the scanning and cutting paths of the continuous laser and the femtosecond pulsed laser to guide the movement of the laser beam, high-efficiency and high-precision additive manufacturing can be achieved.

[0048] (2) By discretizing the three-dimensional geometric model into two-dimensional contour data and biasing it, a precise cutting path can be obtained. By biasing the contour, the continuity and stability of the cutting path can be ensured, errors and deviations can be reduced, cutting quality can be improved, and cutting accuracy can be increased. Attached Figure Description

[0049] 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 only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0050] Figure 1 This is a flowchart of the method for improving the surface accuracy of laser fused filament deposited components using femtosecond synchronous subtractive manufacturing, according to the present invention.

[0051] Figure 2 This is a schematic diagram of the method for improving the surface accuracy of laser filament deposited components using femtosecond synchronous subtractive material processing according to the present invention.

[0052] Key reference numerals:

[0053] 1. Additive manufacturing components; 2. Continuous laser; 3. Original rough surface; 4. Ablated materials; 5. Femtosecond polished surface; 6. Laser-material interaction area; 7. Femtosecond pulsed laser. Detailed Implementation

[0054] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0055] like Figure 1 and Figure 2 As shown, the present invention provides a method for improving the surface accuracy of laser filament-deposited components by femtosecond synchronous subtractive manufacturing, comprising the following steps:

[0056] S1. Set up dual heat sources, the dual heat sources include continuous laser 2 and femtosecond pulse laser 7.

[0057] In the additive manufacturing process, a continuous laser 2 and a femtosecond pulsed laser 7 are used as dual heat sources. The continuous laser 2 is used for molten wire deposition of metal wire, and the femtosecond pulsed laser 7 is used for subtractive processing of the original rough surface 3 of the additive manufacturing component 1.

[0058] S2. Use computer-aided design software to create a three-dimensional geometric model of additive manufacturing component 1, and use slicing software to slice the three-dimensional geometric model into layers.

[0059] Using computer-aided design software, a three-dimensional geometric model is established based on the requirements and design of additive manufacturing component 1. The three-dimensional geometric model is then sliced ​​into layers using slicing software.

[0060] S3. Discretize the three-dimensional geometric model into two-dimensional contour data, and plan the scanning path of the continuous laser 2 and the cutting path of the femtosecond pulse laser 7.

[0061] Based on two-dimensional contour data, slicing software is used to determine the scanning path of continuous laser 2, and a path planning algorithm is used to determine the cutting path of femtosecond pulse laser 7. The scanning path and the cutting path guide the movement of the laser beam to achieve simultaneous subtractive material deposition of metal wire and surface of additive manufacturing components.

[0062] S4. Set the printing parameters for the continuous laser welding torch and the cutting parameters for the femtosecond pulsed laser welding torch. The printing parameters include laser power, scanning speed, and scanning spacing, which directly affect the molten wire deposition effect and quality.

[0063] S5. According to the printing parameters of the continuous laser welding gun, the metal wire is deposited along the scanning path, and at the same time, the femtosecond pulsed laser welding gun performs subtractive processing on the surface of the additive manufacturing component 1 according to the cutting path.

[0064] The continuous laser deposits the molten metal wire according to the scanning path planned by the slicing software to form the solid part of the additive manufacturing component 1. At the same time, according to the cutting parameters of the femtosecond pulse laser welding gun, the surface of the additive manufacturing component 1 is subjected to subtraction processing, that is, the material 4 to be ablated on the original rough surface 3 is subjected to subtraction processing to ensure that the surface of the additive manufacturing component is flat and forms a femtosecond polished surface 5.

[0065] S6. Repeat steps S4-S5 to complete the layer-by-layer stacking of additive manufacturing component 1 until a three-dimensional solid component is obtained.

[0066] In this embodiment of the application, by using a combination of dual heat sources, continuous laser 2 and femtosecond pulsed laser 7 can achieve high-efficiency and high-precision additive manufacturing. Continuous laser 2 can achieve rapid printing of the main body of the additive manufacturing component 1, while the characteristics of femtosecond pulsed laser 7 enable simultaneous subtraction to improve the accuracy of the inner and outer surfaces of the additive manufacturing component 1 by planning the cutting path and setting the laser cutting parameters.

[0067] In one embodiment of this application, step S3 specifically includes:

[0068] S31. Discretize the three-dimensional geometric model into two-dimensional contour data;

[0069] S32. Based on the two-dimensional contour data, distinguish the inner contour region and the outer contour region of the polygonal contour obtained by slicing.

[0070] S33. Offset the outer contour outward and the inner contour inward;

[0071] S34. Use the offset contour as the cutting path of the femtosecond pulsed laser 7.

[0072] Specifically, the 3D geometric model is cut into a series of 2D slices parallel to the bottom of the additive manufacturing component 1 using slicing software. Each slice represents a cross-section of the additive manufacturing component 1 at a corresponding height. For each slice, it is divided into an inner contour region and an outer contour region based on the direction and relative position of the polygonal contour. The inner contour region represents the holes inside the additive manufacturing component 1, and the outer contour region represents the boundary of the additive manufacturing component 1. According to the femtosecond laser scanning cutting requirements and the diameter of the laser beam, the outer contour is offset outward so that the cutting path is outside the outer contour. Simultaneously, the inner contour is offset inward so that the cutting path is inside the inner contour. The new outer contour and the new inner contour after offset are used as the cutting path of the femtosecond pulsed laser 7 for surface subtractive processing.

[0073] Understandably, step S33 specifically includes:

[0074] Using the offset tool, a new outer contour is generated by offsetting a specified distance outward at each point of the outer contour; that is, the offset algorithm is applied to the outer contour to expand the outer contour outward by a preset offset distance, where the preset offset distance can be determined according to the scanning and cutting requirements and the diameter of the laser beam.

[0075] Using the offset tool, a new inner contour is generated by offsetting a specified distance inward at each point of the inner contour; that is, the offset algorithm is applied to the inner contour to shrink the inner contour inward by a preset offset distance, where the preset offset distance can also be determined according to the scanning and cutting requirements and the diameter of the laser beam.

[0076] The offset distances of the outer and inner contours are adjusted to obtain the new dimensions and shapes of the outer and inner contours.

[0077] The offset algorithm can be an offset curve algorithm, an offset polygon algorithm, or it can calculate the offset contour based on the shape and direction of the contour set. This application does not impose any specific restrictions on this.

[0078] Step S33 uses the offset tool to generate a new inner contour, which can make the cutting line closer to the original design, reduce errors and deviations, and thus improve cutting accuracy; using the offset tool to generate a new outer contour can make the cutting line smoother and more uniform, reduce unevenness and defects in the cutting process, and thus improve cutting quality; and the size and shape can be flexibly adjusted according to actual needs to meet different design requirements.

[0079] In one embodiment of this application, step S34 specifically includes:

[0080] S341. Use the offset contour as part of the cutting path to obtain a set of multiple offset paths with the same spacing.

[0081] S342. Calculate the femtosecond pulse laser cutting deviation on each cutting path in the bias path set; wherein, the femtosecond pulse laser cutting deviation refers to the difference between the theoretical width of the cross-section to be cut and the actual width of the cut cross-section during the actual cutting process. The femtosecond pulse laser cutting deviation can be calculated by simulation or actual cutting test.

[0082] S343. Compare the femtosecond pulse laser cutting deviation with a first set threshold. If the femtosecond pulse laser cutting deviation is greater than the first set threshold, adjust the cutting path.

[0083] S344, Output the optimized cutting path.

[0084] Understandably, the offset path set is a group of parallel paths generated based on the offset contour, and these parallel paths maintain the same spacing as the original contour. If the femtosecond pulse laser cutting deviation on a certain offset path exceeds a first preset threshold, it indicates that the offset path does not meet the final cutting requirements. In this case, the offset path needs to be adjusted to reduce the deviation and improve the cutting quality. The first preset threshold is set according to actual usage requirements, and this application does not specifically limit it.

[0085] In the embodiments of this application, by adjusting the cutting path, the cutting deviation of femtosecond pulse laser can be reduced, thereby obtaining a more precise and accurate cutting result.

[0086] Furthermore, step S343 specifically includes:

[0087] During laser cutting, record the theoretical width of the cross-section to be cut and the actual width of the cross-section already cut for each cut;

[0088] The theoretical width of the cross-section to be cut is compared with the actual width of the cut cross-section to calculate the femtosecond pulse laser cutting deviation.

[0089] The femtosecond pulse laser cutting deviation is compared with a first set threshold. If the femtosecond pulse laser cutting deviation is greater than the first set threshold, the cutting path is adjusted.

[0090] After the cutting path is adjusted, laser cutting is performed again until the femtosecond pulse laser cutting deviation is less than the first set threshold.

[0091] In this embodiment of the application, during laser cutting, the theoretical width of the cross-section to be cut and the actual width of the cross-section already cut are recorded for each cut. The femtosecond pulse laser cutting deviation is obtained by calculating the difference between the actual width of the cross-section already cut and the theoretical width of the cross-section to be cut. The femtosecond pulse laser cutting deviation is compared with a first set threshold. If the femtosecond pulse laser cutting deviation is greater than the first set threshold, it means that the cutting path does not meet the final cutting requirements and the cutting path needs to be adjusted. Laser cutting continues until the femtosecond pulse laser cutting deviation is less than the first set threshold.

[0092] This application embodiment monitors and adjusts the cutting deviation of femtosecond pulse laser. When the cutting deviation of femtosecond pulse laser exceeds the set threshold, the cutting path is adjusted in time, which can effectively reduce the cutting deviation and thus improve the cutting accuracy.

[0093] By monitoring and adjusting the femtosecond pulsed laser cutting deviation, excessive deviations can be avoided, resulting in smoother and finer cutting edges. Timely monitoring and adjustment of the femtosecond pulsed laser cutting deviation can reduce unnecessary cutting operations and repetitive work, and also avoid unnecessary cutting processes, thereby saving costs and resources.

[0094] Furthermore, the formula for calculating the cutting deviation of a femtosecond pulsed laser is as follows:

[0095]

[0096] Where Δ represents the cutting deviation, b t b represents the theoretical width of the cross-section to be cut, and b represents the actual width of the cross-section that has been cut.

[0097] b t =(n-1)c+w

[0098] Where n represents the number of cuts, c represents the scanning interval of the femtosecond pulse laser, and w represents the width of one femtosecond pulse laser cut.

[0099] In one embodiment of this application, step S5 specifically includes:

[0100] Using the continuous laser welding torch, molten wire is deposited along the scanning path;

[0101] Based on the shape and surface accuracy requirements of the additively manufactured component 1, the cutting path of the femtosecond pulsed laser welding gun is planned.

[0102] The inner and outer surfaces of the additively manufactured component 1 are subjected to subtractive processing using a femtosecond pulsed laser welding torch.

[0103] Specifically, the scanning path of the continuous laser is planned using slicing software, and the metal wire is deposited along the scanning path using the continuous laser welding gun. According to the shape and surface accuracy requirements of the additive manufacturing component 1, the cutting path of the femtosecond pulse laser welding gun is planned, and a suitable path and direction are selected to ensure the stability and continuity of the scanning and cutting process.

[0104] In the embodiments of this application, high-efficiency additive manufacturing can be achieved by using a continuous laser welding gun to print additive manufacturing components; surface subtractive processing using a femtosecond pulsed laser welding gun can simultaneously improve the surface quality of additive manufacturing components and achieve high-precision additive manufacturing; and reasonable planning of the cutting path of the femtosecond pulsed laser welding gun can adapt to the cutting requirements of complex shapes and achieve high-precision cutting.

[0105] In one embodiment of this application, the femtosecond pulsed laser welding gun has a wavelength of 1000-1050nm, a pulse frequency of 10-1000kHz, and a power of 5-200W.

[0106] Understandably, femtosecond pulsed laser welding torches have very short pulse widths (typically between hundreds and tens of femtoseconds), which allows them to provide high-energy-density laser beams in a very short time. The processing is also highly precise and controllable, enabling high-precision cutting, making them particularly suitable for applications requiring high cutting accuracy. In the embodiments of this application, the femtosecond pulsed laser welding torch can achieve high-precision subtractive cutting of additive manufacturing components.

[0107] In one embodiment of this application, the continuous laser welding gun has a laser power of 1000W to 10000W, a laser scanning speed of 10 to 15m / min, and a wire feeding speed of 10 to 20m / min.

[0108] Understandably, continuous laser welding torches possess high laser power and scanning speed, enabling prolonged laser output and achieving highly efficient molten wire deposition, making them particularly suitable for applications with high printing speed requirements. In the embodiments of this application, the continuous laser welding torch can achieve precise control of the printing process by controlling the laser power and scanning speed, making the printing process more stable and controllable, improving printing quality and consistency, and ultimately achieving high-efficiency additive manufacturing.

[0109] Optionally, the continuous laser welding gun uses a metal welding wire, wherein the metal welding wire is a cable-type titanium alloy, stainless steel or high-temperature alloy welding wire, the wire diameter is 1.2 to 2.4 mm, and the wire feeding speed is 10 to 20 m / min.

[0110] In one embodiment of this application, during the layer-by-layer stacking process of the additive manufacturing component 1 in step S6, an inert protective gas is introduced at an angle into the laser-material interaction region 6. This not only ensures the quality and performance of the additive manufacturing component 1, reduces the oxidation of the metal material, and prevents external impurities from entering the laser-material interaction region 6, but also improves the purity of the additive manufacturing component 1 and enhances the printing quality and stability.

[0111] Furthermore, the inert protective gas is argon or helium, etc.

[0112] In this embodiment, a continuous laser 2 and a femtosecond pulsed laser 7 are used as dual heat sources. The continuous laser 2 melts the filament for high-efficiency deposition, while the femtosecond pulsed laser 7 precisely ablates the inner / outer surfaces of the additive manufacturing component. A three-dimensional geometric model of the additive manufacturing component 1 is established using computer-aided design software. Then, slicing software is used to slice the geometric model layer by layer, discretizing the three-dimensional entity into a series of two-dimensional data. Simultaneously, the cutting path of the femtosecond pulsed laser 7 and the scanning path of the continuous laser 2 are planned. The cutting parameters of the femtosecond pulsed laser welding torch and the printing parameters, scanning path, and cutting path of the continuous laser welding torch are set. The process involves controlling the printing process to improve the surface accuracy of the additively manufactured component 1. A starting point is selected on the forming substrate, and an inert protective gas is pre-introduced. The first layer is deposited according to a pre-set continuous laser scanning path 2, followed by simultaneous cutting and subtraction of the first layer according to a pre-set femtosecond pulse laser 7 cutting path, achieving a highly efficient and precise additive-subtractive process. After completing the first layer deposition and simultaneous subtraction, a second layer deposition and simultaneous subtraction process is performed on the first printed layer. This process of deposition and cutting subtraction is repeated until femtosecond simultaneous subtraction is completed, thus improving the surface accuracy of the additively manufactured component.

[0113] This application also provides a system for improving the surface accuracy of laser fused filament deposited components using femtosecond synchronous subtractive manufacturing, comprising:

[0114] The path planning module is used to discretize the three-dimensional geometric model of the additive manufacturing component created using computer-aided design software into two-dimensional contour data, and plan the scanning path of continuous laser and the cutting path of femtosecond pulse laser.

[0115] The parameter setting module is used to set the printing parameters of the continuous laser welding gun and the cutting parameters of the femtosecond pulse laser welding gun.

[0116] A continuous laser welding torch is used to deposit molten wire along a scanning path;

[0117] Femtosecond pulsed laser welding guns are used to perform subtractive processing on the surface of additively manufactured components.

[0118] This application uses a path planning module to discretize the 3D model into 2D contour data. The layered 2D contour data is then processed to determine the movement trajectory of the laser welding gun during the printing process, ensuring printing accuracy and consistency. The parameter setting module sets the printing parameters for the continuous laser welding gun and the cutting parameters for the femtosecond pulsed laser welding gun to meet different printing needs and material properties. This makes it suitable for printing various materials, such as titanium alloys, stainless steel, and high-temperature alloys, increasing the system's flexibility and application areas. The continuous laser welding gun deposits molten metal wire along the scanning path, while the femtosecond pulsed laser welding gun performs subtractive processing on the surface of the additively manufactured component 1, achieving precise control of the cutting process, improving production efficiency, and reducing subtractive processing time.

[0119] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. 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 method for improving the surface accuracy of laser filament-deposited components through femtosecond synchronous subtractive manufacturing, characterized in that, Includes the following steps: S1. Set up dual heat sources, wherein the dual heat sources include continuous laser and femtosecond pulsed laser; S2. Use computer-aided design software to create a three-dimensional geometric model of the additive manufacturing component, and use slicing software to slice the three-dimensional geometric model into layers. S3. Discretize the three-dimensional geometric model into two-dimensional contour data, and plan the scanning path of the continuous laser and the cutting path of the femtosecond pulse laser. Step S3 specifically includes: S31. Discretize the three-dimensional geometric model into two-dimensional contour data; S32. Based on the two-dimensional contour data, distinguish the inner contour region and the outer contour region of the polygonal contour obtained by slicing. S33. Offset the outer contour outward and the inner contour inward; S34. Use the offset contour as the cutting path of the femtosecond pulse laser; Step S34 specifically includes: S341. Use the offset contour as part of the cutting path to obtain a set of multiple offset paths with the same spacing. S342. Calculate the femtosecond pulse laser cutting deviation on each cutting path in the bias path set; the expression is: ； In the formula, Indicates cutting deviation, b t b represents the theoretical width of the cross-section to be cut, and b represents the actual width of the cross-section that has been cut. ； In the formula, n represents the number of cuts, c represents the scanning interval of the femtosecond pulse laser, and w represents the width of one femtosecond pulse laser cut; S343. Compare the femtosecond pulse laser cutting deviation with a first set threshold. If the femtosecond pulse laser cutting deviation is greater than the first set threshold, adjust the cutting path. S344, Output the optimized cutting path; S4. Set the printing parameters of the continuous laser welding gun and the cutting parameters of the femtosecond pulse laser welding gun; S5. According to the printing parameters of the continuous laser welding gun, the metal wire is deposited according to the scanning path, and at the same time, the femtosecond pulsed laser welding gun performs subtractive processing on the surface of the additive manufacturing component according to the cutting path. S6. Repeat steps S4-S5 to complete the layer-by-layer stacking of additive manufacturing components until a three-dimensional solid component is obtained.

2. The method for improving the surface accuracy of laser filament deposited components by femtosecond synchronous subtractive manufacturing as described in claim 1, characterized in that, Step S343 specifically includes: During laser cutting, record the theoretical width of the cross-section to be cut and the actual width of the cross-section already cut for each cut; The theoretical width of the cross-section to be cut is compared with the actual width of the cut cross-section to calculate the femtosecond pulse laser cutting deviation. The femtosecond pulse laser cutting deviation is compared with a first set threshold. If the femtosecond pulse laser cutting deviation is greater than the first set threshold, the cutting path is adjusted. After the cutting path is adjusted, laser cutting is performed again until the femtosecond pulse laser cutting deviation is less than the first set threshold.

3. The method for improving the surface accuracy of laser filament deposited components by femtosecond synchronous subtractive manufacturing as described in claim 1, characterized in that, Step S33 specifically includes: Use the offset tool to offset outwards by a specified distance at each point of the outer contour to generate a new outer contour; Use the offset tool to offset inward by a specified distance at each point of the inner contour to generate a new inner contour; The offset distances of the outer and inner contours are adjusted to obtain the new dimensions and shapes of the outer and inner contours.

4. The method for improving the surface accuracy of laser filament deposited components by femtosecond synchronous subtractive manufacturing as described in claim 1, characterized in that, Step S5 specifically includes: Using the continuous laser welding torch, molten wire is deposited along the scanning path; Based on the shape and surface precision requirements of the additively manufactured components, the cutting path of the femtosecond pulsed laser welding gun is planned; The inner and outer surfaces of additively manufactured components are processed using a femtosecond pulsed laser welding torch.

5. The method for improving the surface accuracy of laser filament deposited components by femtosecond synchronous subtractive manufacturing as described in claim 1, characterized in that, The femtosecond pulsed laser welding gun has a wavelength of 1000–1050 nm, a pulse frequency of 10–1000 kHz, and a power of 5–200 W.

6. The method for improving the surface accuracy of laser filament deposited components by femtosecond synchronous subtractive manufacturing as described in claim 1, characterized in that, The continuous laser welding gun has a laser power of 1000W~10000W, a laser scanning speed of 10~15m / min, and a wire feeding speed of 10~20m / min.

7. The method for improving the surface accuracy of laser filament deposited components by femtosecond synchronous subtractive manufacturing as described in claim 1, characterized in that, In step S6, during the layer-by-layer deposition of the additive manufacturing component, an inert protective gas is introduced at an angle into the laser-material interaction region.

8. A system for improving the surface accuracy of laser filament-deposited components through femtosecond synchronous subtractive manufacturing, characterized in that, The method described in any one of claims 1-7 includes: The path planning module is used to discretize the three-dimensional geometric model of the additive manufacturing component created using computer-aided design software into two-dimensional contour data, and plan the scanning path of continuous laser and the cutting path of femtosecond pulse laser. The parameter setting module is used to set the printing parameters of the continuous laser welding gun and the cutting parameters of the femtosecond pulse laser welding gun. A continuous laser welding torch is used to deposit molten wire along a scanning path; Femtosecond pulsed laser welding guns are used to perform subtractive processing on the surface of additively manufactured components.

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