Combination optimization method for different sharp corner angles in electric arc additive manufacturing
By optimizing the path and welding speed in the sharp corner area, and by adopting a flat-angle transition path and a fixed-angle compensation path optimization method, the problem of material overlap in the sharp corner area was solved, thereby improving the printing quality and processing efficiency of arc additive manufacturing.
Patent Information
- Application Number
- CN202511227451.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-29
- Publication Date
- 2025-11-18
AI Technical Summary
In arc additive manufacturing, excessive overlap of material in sharp corner areas leads to changes in arc length, affecting the manufacturing process, reducing the appearance quality of parts, and increasing the difficulty of subsequent processing.
By optimizing the path and welding speed in the sharp corner area, and using the flat corner transition path optimization method and the fixed angle compensation path optimization method, the overlapping area of the sharp corner area is reduced. Combined with the adjustment of the weld width, the combined optimization of the sharp corner area is achieved.
It significantly reduces the overlapping area in sharp corner regions, improves the quality of arc additive printing, ensures the appearance and processing effect of parts, and has a small computational load and controllable error.
Smart Images
Figure CN120962050A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of electric arc additive manufacturing technology, and more specifically to a method for optimizing the combination of different sharp angles in electric arc additive manufacturing. Background Technology
[0002] Wire-arc DED, with its significant advantages of high deposition efficiency and low cost, is widely used in important fields such as aerospace and defense. In the arc additive manufacturing of large thin-walled metal structures, excessive overlap is prone to occur at sharp corners when using traditional contour paths for printing. As the number of printed layers increases, this not only damages the surface flatness of the printed parts, severely affecting their appearance quality, but also significantly increases the difficulty of subsequent processing. The arc additive manufacturing process is highly sensitive to arc conditions; excessive material overlap in sharp corner areas can cause changes in arc length, affecting the manufacturing process. Summary of the Invention
[0003] The purpose of this invention is to solve the problem of molten material accumulation at intersections in the prior art, and to provide a method for optimizing the combination of different sharp angles in arc additive manufacturing. Specifically, it involves a method for optimizing the combination of path and welding speed in arc additive manufacturing. By optimizing the path and welding speed together in the sharp angle region, the accumulation in the sharp angle region is significantly reduced, thereby improving the printing quality of arc additive manufacturing.
[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:
[0005] A method for optimizing combinations of different sharp angles in arc additive manufacturing, the method comprising the following steps:
[0006] S1. Traverse the welding path points and establish a mathematical model of the weld bead corner region. The area where weld beads overlap at the corners of the path is the corner region. Divide the corner region into stable overlapping region and excessive overlapping region.
[0007] S2. Select the path optimization method that minimizes the area of excessive overlap, including the flat-angle transition path optimization method, the fixed-angle compensation path optimization method, or no path optimization. Let the initial weld width be w, and the sharp-angle angle be... The formula for calculating the area of the excessively overlapping region in the flat-angle transition path optimization method is as follows:
[0008] ;
[0009] The formula for calculating the area of the excessively overlapping region in the fixed-angle compensation path optimization method is as follows:
[0010] ;
[0011] The formula for calculating the area of the excessively overlapping region when no path optimization is performed is as follows:
[0012] ;
[0013] S3. Determine the optimized weld width, specifically the optimized weld width for the flat angle transition path. The weld width after fixed angle compensation path optimization The welding speed is determined based on the optimized weld width.
[0014] Further, in step S1, the method for dividing the stable overlapping region and the excessive overlapping region is as follows: within the weld bead overlapping region, if the amount of deposits overlapping between adjacent weld beads is less than the gap region between adjacent weld beads, it is a stable overlapping region; if the amount of deposits overlapping between adjacent weld beads is greater than the gap region between adjacent weld beads, it is an excessive overlapping region.
[0015] Further, in step S2, the steps of the flat angle transition path optimization method include:
[0016] The vertex at the sharp corner is Select two symmetrical points from the sharp corner region. , Let the distance between the two points be L; from , The two points move along the angle bisector of the apex towards the inflection point. Thus obtain and Two points, then use the path Replace the original path .
[0017] Furthermore, in the steps of the flat angle transition path optimization method, , The distance L between the two points is taken as an initial weld width w.
[0018] Further, in step S2, the steps of the fixed-angle compensation path optimization method include:
[0019] The vertex at the sharp corner is Adjacent points are , With sharp corners Using the weld width w as the center, draw an arc r with radius r, offsetting the original path outward. The distance, the intersection of the arc and the offset path is and Construct a line segment equal line segment equal ,in The point is on the original path, using the path Replace the original path .
[0020] Furthermore, with = The value of θ at that time is the included angle of the first weld bead, with = The value of θ at that time is the included angle of the second weld bead;
[0021] When 0 < If the angle of the first weld bead is less than or equal to the included angle of the first weld bead, the path is optimized using a flat-angle transition path. For angles ≤ θ of the second weld bead, the path is optimized using a fixed angle compensation method; for sharp angles where the angle of the second weld bead is < θ, no path optimization is performed.
[0022] Furthermore, the included angle of the first weld bead is 46.41°, and the included angle of the second weld bead is 114.75°; for the sharp angle range is... For paths in sharp-corner regions, a flat-corner transition path optimization method is adopted; for sharp-corner ranges of... For paths in sharp-angle regions, a fixed-angle compensation path optimization method is used; for Sharp corners are not subject to path optimization.
[0023] The advantages of this invention are reflected in:
[0024] 1) Compared with the traditional method of optimizing the sharp corner by only optimizing the welding speed, this invention optimizes the two variables of sharp corner angle and weld width simultaneously according to the formula of overlapping area, which greatly reduces the overlapping area of the sharp corner area. Under the premise of ensuring that the shape of the sharp corner area remains constant, it achieves dual precise optimization of its excessive overlapping area and outer contour size. The combined optimization method of this invention can significantly reduce the accumulation of sharp corner area in the deposition construction direction.
[0025] 2) Requires less information, less computation, and less dependence: During the optimization process, there is no need to obtain relevant information about the robot. Only the path and welding speed are optimized, and the optimization scheme is not limited to a single robot.
[0026] 3) Small error: The error of this invention is controllable, and the maximum deviation between the optimized path and the initial weld path can be limited, making it closer to the initial weld path. Attached Figure Description
[0027] Figure 1 This is a schematic diagram of the division of the sharp corner region in this invention;
[0028] Figure 2 This is a schematic diagram illustrating the optimized flat-angle transition path for the sharp-corner region in this invention.
[0029] Figure 3 This is a schematic diagram illustrating the fixed-angle compensation path optimization method used in the sharp-corner region of this invention.
[0030] Figure 4 This is a schematic diagram comparing the areas of excessively overlapping regions after different path optimizations in the sharp corner region in step S2 of the present invention.
[0031] Figure 5 This is a schematic diagram illustrating the optimized effect of using a flat-angle transition path and welding speed combination in the sharp-corner area of this invention;
[0032] Figure 6 This is a schematic diagram illustrating the optimized effect of using a fixed-angle compensation path and welding speed combination in the sharp corner area in this invention. Detailed Implementation
[0033] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.
[0034] like Figures 1 to 6 As shown, a method for optimizing combinations of different sharp angles in arc additive manufacturing includes the following steps:
[0035] S1. Traverse the welding path points and establish a mathematical model of the weld bead corner region. The area where weld beads overlap at the corners of the path is the corner region. Divide the corner region into stable overlapping region and excessive overlapping region.
[0036] S2. Select the path optimization method that minimizes the area of excessive overlap in the path optimization process, including the flat-angle transition path optimization method, the fixed-angle compensation path optimization method, or no path optimization. Let the initial weld width be w, and the sharp angle be... The formula for calculating the area of the excessively overlapping region without path optimization is as follows:
[0037] (1);
[0038] According to the above formula for calculating the area of the excessively overlapping region, when the weld width w is fixed, as the angle θ of the sharp corner increases, the area of the excessively overlapping region becomes smaller, the amount of overlapping deposition becomes less, and the self-overlapping phenomenon at the sharp corner becomes less obvious. Therefore, this invention optimizes the path at the sharp corner to increase the angle, and proposes a flat angle transition path optimization method and a fixed angle compensation path optimization method for different sharp corner angle ranges.
[0039] The formula for calculating the area of the excessive overlap region in the flat-angle transition path optimization method is as follows:
[0040] (2);
[0041] The formula for calculating the area of the excessively overlapping region in the fixed-angle compensation path optimization method is as follows:
[0042] (3);
[0043] S3. Determine the optimized weld width, specifically the optimized weld width for the flat angle transition path. The weld width after fixed angle compensation path optimization The welding speed is determined based on the optimized weld width.
[0044] In some embodiments, such as Figure 1 As shown, in step S1, the method for dividing the stable overlapping region and the excessive overlapping region is as follows: within the weld bead overlapping region, if the amount of deposits overlapping between adjacent weld beads is less than the gap region between adjacent weld beads, it is a stable overlapping region; if the amount of deposits overlapping between adjacent weld beads is greater than the gap region between adjacent weld beads, it is an excessive overlapping region.
[0045] The formula for calculating the area of a sharp corner region is: When the center distance between two adjacent weld beads is 2w / 3, the surface smoothness is the best. Based on this condition, the sharp corner area is divided into a stable overlapping area and an excessively overlapping area.
[0046] In some preferred embodiments, such as Figure 2 As shown, in step S2, the steps of the flat-angle transition path optimization method include: the vertex at the sharp corner is... Select two symmetrical points from the sharp corner region. , Let the distance between the two points be L; from , The two points move along the angle bisector of the apex towards the inflection point. Thus obtain and Two points, then use the path Replace the original path .
[0047] In some specific embodiments, preferably, in the steps of the flat angle transition path optimization method, , The distance L between the two points is taken as an initial weld width w.
[0048] Based on the overlap characteristics of two adjacent weld passes, if weld bead in path and Gaps will form between them; if Then the weld bead is in the path and The overlapping region is the excessively overlapping region; when weld bead in path and A relatively smooth surface will be produced there, but after... When depositing along a line segment, excessive buildup can occur within the flat corner. Therefore, to avoid excessive buildup and gaps at sharp corners, while ensuring the weld width covers the original path, this invention will... , The distance L between the two points is set to an initial weld width w.
[0049] The flat-angle transition path optimization method in this invention is applicable to sharp corners from 0 to 180°, and non-adjacent weld beads will not overlap, thus only affecting sharp corners. A small amount of accumulation occurred at that location.
[0050] In some embodiments, such as Figure 3 As shown, in step S2, the steps of the fixed-angle compensation path optimization method include: the vertex at the sharp corner is... Adjacent points are , With sharp corners Using the initial weld width w as the center, draw an arc r with radius r, offsetting the original path outward. The distance, the intersection of the arc and the offset path is and Construct a line segment equal line segment equal ,in The point is on the original path, using the path Replace the original path .
[0051] Based on the geometric relationship after the path optimization described above, we can conclude that... , , Considering that stacking may also occur between non-adjacent paths, such as and Segment, point , The center distance and point between , The center distance between them is:
[0052] ;
[0053] when At that time, it can be obtained ,Right now and The segments will not produce excessively overlapping areas.
[0054] The fixed-angle compensation path optimization method increases the angle value at the sharp corners of the path by a fixed value. .when Even non-adjacent paths can generate excessively overlapping areas. Since the calculation of this situation is quite complex, we will now only consider the excessively overlapping area generated by two adjacent sides. According to the area calculation formula (1), we can obtain the area of the sharp corner region after path optimization. The overlapping area and excessive overlap area generated at point ) are:
[0055] .
[0056] From the above three formulas (1)-(3) for calculating the area of excessively overlapping regions, it can be seen that when the areas are equal, the area value is only related to the angle of the sharp corner and is not related to the weld width. Assuming the initial weld width w is 10mm, as follows... Figure 4 As shown, based on the function coordinate graphs of the two path optimization methods and the area of the excessively overlapping region when no path optimization is performed, the method with the smallest excessively overlapping region area among the flat-angle transition path optimization method, fixed-angle compensation path optimization method, and no path optimization is selected. That is, with = The value of θ at that time is the included angle of the first weld bead. = The value of θ at that time is the included angle of the second weld bead; when 0 < If the angle of the first weld bead is less than or equal to the included angle of the first weld bead, the path is optimized using a flat-angle transition path. For angles ≤ θ of the second weld bead, the path is optimized using a fixed angle compensation method; for sharp angles where the angle of the second weld bead is < θ, no path optimization is performed.
[0057] In the specific calculation of the area of the three overlapping regions mentioned above (1)-(3), when the weld width w is 10mm, as follows: Figure 4 As shown, make = The calculated included angle of the first weld bead is 46.41°. = The calculated included angle of the second weld bead is 114.75°. That is, for the sharp angle range... For paths in sharp-corner regions, a flat-corner transition path optimization method is adopted; for sharp-corner ranges of... For paths in sharp-angle regions, a fixed-angle compensation path optimization method is used; for Sharp corners are not subject to path optimization.
[0058] The optimized path of the present invention needs further constraints: in the sharp corner area, the fusion width of the optimized path can cover the original path; the formed parts undergo specific processing in the sharp corner area to restore the original shape as much as possible.
[0059] In some other embodiments, in step S3, according to the area calculation formula (1) for the excessively overlapping region without optimization, when the sharp angle remains unchanged, the area of the excessively overlapping region will also decrease as the weld width decreases. Therefore, it is necessary to select a suitable welding speed for the different path optimization methods used in this invention. Figure 5 and Figure 6 As shown, let's assume For the weld width optimized for speed, the combined optimization of the flat angle transition path is considered, taking into account the optimized forming morphology, let For the combined optimization of fixed-angle compensation path optimization, considering the formed morphology after path optimization, let... Finally, the optimized welding speed is determined by the weld bead width.
[0060] The combined optimization method of the present invention further optimizes the optimized weld bead width, determines the actual welding speed at the sharp corner based on the optimized weld bead width, and finally implements a specific welding scheme based on the optimized path, weld bead width, and welding speed.
[0061] In welding process design and path planning, the optimization of weld bead corners is a key step in improving welding efficiency and quality. This invention proposes a synergistic optimization strategy for speed and path by combining the characteristics of path optimization (reducing overlapping area and increasing outer contour) and welding speed optimization (reducing overlapping area and reducing outer contour) at the corners. This optimizes the contour of the corner area to achieve balance and ultimately make it coincide with the original weld bead contour. While ensuring that the shape of the corner area remains constant, this invention achieves dual precise optimization of its excessive overlap area and outer contour size. The combined optimization method of this invention can significantly reduce the accumulation of corner areas in the deposition construction direction.
[0062] The specific embodiments described in this invention are merely illustrative of the invention and are not intended to limit it. Those skilled in the art can make modifications to these embodiments without contributing any inventive step after reading this specification, but such modifications are protected by patent law as long as they fall within the scope of the claims of this invention.
Claims
1. A method for optimizing combinations of different sharp angles in arc additive manufacturing, characterized in that, The method includes the following steps: S1. Traverse the welding path points and establish a mathematical model of the weld bead corner region. The area where weld beads overlap at the corners of the path is the corner region. Divide the corner region into stable overlapping region and excessive overlapping region. S2. Choose the path optimization method that minimizes the area of the excessively overlapping region in the path optimization method, the flat-angle transition path optimization method, the fixed-angle compensation path optimization method, or no path optimization. Let the initial weld width be w, and the angle of the sharp corner be... The formula for calculating the area of the excessively overlapping region in the flat-angle transition path optimization method is as follows: ； The formula for calculating the area of the excessively overlapping region in the fixed-angle compensation path optimization method is as follows: ； The formula for calculating the area of the excessively overlapping region when no path optimization is performed is as follows: ； S3. Determine the optimized weld width, specifically the optimized weld width for the flat angle transition path. The weld width after fixed angle compensation path optimization The welding speed is determined based on the optimized weld width.
2. The method for optimizing combinations of different sharp angles in arc additive manufacturing according to claim 1, characterized in that, In step S1, the method for dividing the stable overlapping region and the excessive overlapping region is as follows: within the weld bead overlapping region, if the amount of deposits overlapping between adjacent weld beads is less than the gap region between adjacent weld beads, it is a stable overlapping region; if the amount of deposits overlapping between adjacent weld beads is greater than the gap region between adjacent weld beads, it is an excessive overlapping region.
3. The method for optimizing combinations of different sharp angles in arc additive manufacturing according to claim 1, characterized in that, In step S2, the steps of the flat angle transition path optimization method include: The vertex at the sharp corner is Select two symmetrical points from the sharp corner region. , Let the distance between the two points be L; from , The two points move along the angle bisector of the apex towards the inflection point. Thus obtain and Two points, then use the path Replace the original path .
4. The method for optimizing combinations of different sharp angles in arc additive manufacturing according to claim 3, characterized in that, In the steps of the flat angle transition path optimization method , The distance L between the two points is taken as an initial weld width w.
5. The method for optimizing combinations of different sharp angles in arc additive manufacturing according to claim 1, characterized in that, In step S2, the steps of the fixed-angle compensation path optimization method include: The vertex at the sharp corner is Adjacent points are , With sharp corners Using the weld width w as the center, draw an arc r with radius r, offsetting the original path outward. The distance, the intersection of the arc and the offset path is and Construct a line segment equal line segment equal ,in The point is on the original path, using the path Replace the original path .
6. The method for optimizing combinations of different sharp angles in arc additive manufacturing according to claim 1, characterized in that, by = The value of θ at that time is the included angle of the first weld bead, with = The value of θ at that time is the included angle of the second weld bead; When 0 < If the angle of the first weld bead is less than or equal to the included angle of the first weld bead, the path is optimized using a flat-angle transition path. For angles ≤ θ of the second weld bead, the path is optimized using a fixed angle compensation method; for sharp angles where the angle of the second weld bead is < θ, no path optimization is performed.
7. The method for optimizing combinations of different sharp angles in arc additive manufacturing according to any one of claims 1, characterized in that, The included angle of the first weld bead is 46.41°, and the included angle of the second weld bead is 114.75°; for sharp angles... For paths in sharp-corner regions, a flat-corner transition path optimization method is adopted; for sharp-corner ranges of... For paths in sharp-angle regions, a fixed-angle compensation path optimization method is used; for Sharp corners are not subject to path optimization.