Short pulse laser assisted continuous laser welding device and method

Abstract

The invention discloses a short pulse laser assisted continuous laser welding device and method. The method comprises the steps that materials are laid; a welding area is divided, and the whole welding area is divided into small areas; performing feature extraction on the small regions; constructing a speed mapping table according to the extracted different features; and planning a laser scanning path according to the speed mapping table. The short-pulse laser-assisted continuous laser welding device and method have the beneficial effects that near-infrared wavelength laser (such as 1064nm) is selected in the whole welding process, and the characteristics of high reflectivity of titanium alloy to the wavelength, high absorptivity of thermoplastic resin, relatively low absorptivity of a resin part in a thermosetting composite material and poor absorptivity of carbon fibers to the wavelength are utilized; laser energy is mainly concentrated on the thermoplastic resin layer, and local heating is achieved. The method comprises the following steps: dividing a region into small regions, extracting features, constructing a speed mapping table, controlling laser energy input, and reducing heat affected zones of the titanium alloy and the thermosetting composite material.

Description

Technical Field

[0001] The present invention belongs to the technical field of laser welding, and in particular relates to a short-pulse laser-assisted continuous laser welding device and method. Background Art

[0002] With the development of modern industry, high-performance materials are increasingly used, especially in aerospace, automobile manufacturing, shipbuilding, sports equipment, and electronic products. These fields require materials not only in terms of strength and durability, but also in terms of lightness, corrosion resistance, and high temperature resistance.

[0003] Traditional welding technologies often fail to meet the welding requirements of these high-performance materials, especially when dealing with dissimilar materials, such as welding between metals and composites.

[0004] For example, titanium alloy has a high reflectivity to near-infrared wavelength (such as 1064nm) lasers, which means that most of the laser energy will be reflected and only a small amount of energy will be absorbed by the titanium alloy. Although this helps to reduce the heat-affected zone of titanium alloys and avoid excessive heating and deformation, it also increases the difficulty of welding.

[0005] On the other hand, thermoplastic resin has a high absorption rate for near-infrared wavelength (such as 1064nm) lasers, and the laser energy can be effectively absorbed by the thermoplastic resin layer, causing it to heat up and melt rapidly. However, if the laser energy is not properly controlled, it is easy to cause the resin to overheat and burn.

[0006] In addition, the resin part of the thermosetting composite material also has a certain absorption capacity for near-infrared wavelength lasers, but the absorption rate is lower than that of thermoplastic resins. Carbon fiber absorbs ultraviolet wavelengths (such as 355nm) lasers better, but absorbs near-infrared wavelengths (such as 1064nm) poorly. Summary of the invention

[0007] In order to solve the problems raised in the above background technology, the present invention provides a short-pulse laser-assisted continuous laser welding device and method.

[0008] To achieve the above object, the present invention provides the following technical solution: a short pulse laser assisted continuous laser welding method, comprising the following steps:

[0009] A short pulse laser assisted continuous laser welding method comprises the following steps:

[0010] S1. Laying the materials; the laying method is: placing the titanium alloy plate and the carbon fiber reinforced epoxy resin composite material plate on the tooling so that the overlapping surfaces are completely aligned, then evenly laying the PA6 thermoplastic resin film on the overlapping surface, and using the resin laying equipment to level the resin layer; the overlapping area after laying is the welding area;

[0011] S2. Divide the welding area into small areas;

[0012] S3, extract features from small areas;

[0013] The feature extraction method is as follows: using a 3D scanner to scan each small area and extract features including flatness, thickness and curvature;

[0014] S4, constructing a speed mapping table according to the extracted different features;

[0015] S5, planning the laser scanning path according to the speed mapping table;

[0016] Further: wherein the size of the small area is a square with a side length of 10 mm to 50 mm or a circle with a diameter of 10 mm to 50 mm;

[0017] Further: The flatness calculation method is: calculate the standard deviation based on the surface height data of each small area, and the calculation formula is:

[0018] h i It represents the height value measured at the i-th measuring point when performing three-dimensional scanning on a small area. In the welding process, h i The height value reflects the relative height of the titanium alloy plate, carbon fiber reinforced epoxy resin composite plate and the PA6 thermoplastic resin film laid on its surface at the measuring point. It is related to the flatness of the laid resin layer and is used to accurately describe the microscopic undulation of the surface of the welding area.

[0019] It represents the average height, which is the arithmetic mean of the height values ​​of all measuring points in the small area. It is a benchmark value for measuring the surface height of the entire small area. By comparing it with the height value of each measuring point, the degree of height dispersion is calculated to determine the flatness.

[0020] N is the number of measurement points. The more measurement points there are, the more accurate the evaluation of the surface flatness of a small area will be. When extracting features, the number depends on the sampling density setting of the 3D scanner used. High-density sampling can capture the surface features of the welding area more carefully and provide sufficient data support for accurate calculation of flatness.

[0021] σ represents the surface height of the small area relative to the average height The larger the standard deviation, the greater the change in surface height, that is, the worse the flatness; the smaller the standard deviation, the flatter the surface.

[0022] The thickness calculation method is to calculate the average thickness of each small area, and the calculation formula is:

[0023] t i It indicates the thickness value measured at the i-th measuring point when measuring the thickness of a small area. The thickness here refers to the vertical distance from the lap joint of the titanium alloy plate and the carbon fiber reinforced epoxy resin composite plate to its surface, reflecting the actual thickness at different positions in the welding area.

[0024] N represents the number of measuring points, and its meaning is similar to that in the flatness calculation formula. Depending on the sampling setting of the measuring equipment, more measuring points help to obtain a more accurate average thickness value, thus providing a comprehensive understanding of the thickness distribution of the welding area.

[0025] t represents the calculated average thickness, which represents the average thickness of the entire material in the small area.

[0026] The curvature calculation method is to calculate the maximum curvature of each small area, and the calculation formula is:

[0027] z represents the surface height, which is a dimension in the three-dimensional coordinate system that describes the surface shape of the welding area. It is associated with the height measurement in the flatness calculation and is used to describe the degree of curvature of the surface. The change in its value reflects the undulation of the welding area surface in the vertical direction.

[0028] x represents the horizontal coordinate, which is another dimension in the three-dimensional coordinate system. Together with z, it determines the position of each point on the surface of the welding area. By calculating the curvature of the second-order partial derivative of z with respect to x, the curvature change of the surface in the horizontal direction can be accurately described, so as to fully grasp the shape characteristics of the welding area, so as to adjust the laser scanning path and welding speed and other parameters according to the curvature during the welding process, ensure that the laser energy can be evenly distributed in the area with larger curvature, and ensure the consistency of welding quality.

[0029] κ represents the calculated maximum curvature, which characterizes the maximum curvature of the surface in the small area. In welding, changes in curvature will cause changes in the incident angle and energy distribution of the laser on the surface, affecting the melting of the resin and the bonding effect with other materials. Accurate calculation of curvature is conducive to optimizing welding process parameters and ensuring welding quality.

[0030] Further: wherein, the speed mapping table is constructed by:

[0031] Adjust the welding speed according to the flatness. According to the pre-established welding speed database, select the welding speed corresponding to the flatness. When σ>σ1, v f =v1; when σ≤σ1, v f =v2;

[0032] σ1 represents the flatness threshold; v1 represents the welding speed for high flatness; v2 represents the welding speed for low flatness; v f Indicates the welding speed corresponding to the flatness;

[0033] Adjust the welding speed according to the thickness. According to the relationship model between thickness and welding speed, select the welding speed corresponding to the thickness. When t>t1, v t =v3; when t≤t1, v t =v4;

[0034] t1 represents the thickness threshold; v3 represents the welding speed corresponding to thin thickness; v4 represents the welding speed corresponding to thick thickness; v t Expressed as welding speed corresponding to thickness;

[0035] Adjust the welding speed according to the curvature. According to the change curve of curvature and welding speed, select the welding speed corresponding to the curvature. When κ>κ1, v κ =v5; when κ≤κ1, v κ =v6;

[0036] κ1 represents the threshold value of curvature; v5 represents the welding speed of large curvature; v6 represents the welding speed of small curvature; v κ Expressed as the velocity corresponding to the curvature;

[0037] For each small area, by comparing v f 、v t 、v κ The welding speed is determined by the size of the welding speed, and the minimum value is selected as the final welding speed; and a speed mapping table is created using the database management system to record the number, characteristic data and final welding speed of each small area one by one to ensure the integrity and accuracy of the data.

[0038] Further: wherein the laser scanning path planning method is:

[0039] Generate a preliminary scanning path for each small area using the grid method or Dijkstra algorithm to ensure that the path covers the entire small area and minimizes the path length;

[0040] Use path optimization algorithms (such as genetic algorithms, particle swarm optimization algorithms, etc.) to optimize the generated path to ensure that the path is shortest and evenly distributed, and the laser beam can evenly cover the area with large curvature;

[0041] Use a connection algorithm (such as the traveling salesman problem TSP algorithm) to connect the paths of each small area into a complete path, ensure the continuity and integrity of the path, optimize the path connection, and ensure that the total length of the path is the shortest.

[0042] Further: short pulse laser and continuous laser are used to work together, so that the laser energy can be precisely focused on the PA6 thermoplastic resin film according to the plan, causing it to heat up and melt quickly, achieving a stable connection of the materials, while strictly controlling the heat affected zone and ensuring high-precision welding, giving full play to the advantages of different materials, and improving the comprehensive performance and durability of the product. Among them, the selected laser can be a laser with a wavelength in the near-infrared range (such as 1064nm).

[0043] Further: wherein, the welding area is divided into small areas by using CNC cutting or laser marking technology so that the area boundaries are clear and distinct, the transition between adjacent areas is smooth, and the entire welding area is divided without omissions and overlaps.

[0044] Further: Among them, the resolution of the 3D scanner is not less than 0.01mm, the measurement accuracy error is within ±0.005mm, and the scanning process follows the predetermined scanning path and sampling density to ensure the acquisition of comprehensive and accurate data.

[0045] Further: A short pulse laser assisted continuous laser welding device, used to implement the above method, comprising:

[0046] Tooling, used to fix titanium alloy plates and carbon fiber reinforced epoxy resin composite plates to ensure that their lap surfaces are aligned;

[0047] Resin laying equipment, used to evenly lay PA6 thermoplastic resin film on the overlapping surface and level the resin layer;

[0048] 3D scanner, with a resolution of not less than 0.01mm and a measurement accuracy error within ±0.005mm, is used to scan small areas of the welding area and extract features including flatness, thickness and curvature;

[0049] Database management system, used to store welding speed database and generate speed mapping table, and perform computational tasks such as feature extraction, speed mapping table construction and laser scanning path planning;

[0050] CNC cutting or laser marking equipment: used to accurately divide the welding area into multiple small areas, ensuring clear and distinct area boundaries, smooth transition between adjacent areas, and no omissions or overlaps in the entire welding area;

[0051] Laser welding equipment, including short-pulse laser sources and continuous laser sources, as well as laser beam guiding and control devices, can efficiently weld the welding area according to the planned laser scanning path.

[0052] The present invention solves the defects existing in the background technology and has the following beneficial effects:

[0053] 1. The short-pulse laser-assisted continuous laser welding device and method selects near-infrared wavelength laser (such as 1064nm) for the entire welding process, and utilizes the high reflectivity of titanium alloy to this wavelength, the high absorptivity of thermoplastic resin, the relatively low absorption of the resin part in thermosetting composite materials, and the poor absorption of carbon fiber to this wavelength, so that the laser energy is mainly concentrated on the thermoplastic resin layer to achieve local heating. By dividing the area into small areas, feature extraction and speed mapping table construction, the laser energy input is more accurately controlled, further ensuring that the laser energy is distributed as expected, and reducing the heat-affected zone of titanium alloy and thermosetting composite materials.

[0054] 2. The short-pulse laser-assisted continuous laser welding device and method, based on the high absorption rate of thermoplastic resin to near-infrared wavelength laser, selects a suitable PA6 thermoplastic resin film during material preparation, and ensures that it is evenly laid and flat during the laying step, so that it can fully absorb the laser energy and quickly heat up and melt during welding. During the welding process, the laser energy input is adjusted according to the characteristics of the resin layer (such as thickness, flatness, etc.). For example, when constructing the speed mapping table, the welding speed is adjusted according to the different thicknesses of the resin layer to ensure that the resin layer can be completely melted and well combined with other materials, and at the same time, no adverse effects will be caused by excessive energy.

[0055] 3. The short-pulse laser-assisted continuous laser welding device and method selects a laser with a wavelength in the near-infrared range (such as 1064nm), and utilizes the fact that the resin part of the thermosetting composite material has a certain but relatively low absorption capacity for near-infrared wavelength lasers, and the carbon fiber has a poor absorption of this wavelength, thereby reducing damage to the carbon fiber during the welding process. In the feature extraction step, the features of the composite material area are accurately obtained. When constructing the speed mapping table, the welding speed is adjusted by comprehensively considering the overall situation of the composite material, so that the laser energy mainly acts on the resin part to promote connection, while protecting the structural integrity of the carbon fiber and maintaining the high performance of the composite material. This composite technology can effectively combine the advantages of different materials to improve the overall performance and durability of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0057] Figure 1 It is a schematic diagram of the process of the present invention; DETAILED DESCRIPTION

[0058] The present invention will now be further described in detail with reference to the accompanying drawings and embodiments. These drawings are simplified schematic diagrams that only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0059] like Figure 1 A short pulse laser assisted continuous laser welding method is shown, comprising the following steps:

[0060] S1. Laying the materials; the laying method is: placing the titanium alloy plate and the carbon fiber reinforced epoxy resin composite material plate on the tooling so that the overlapping surfaces are completely aligned, then evenly laying the PA6 thermoplastic resin film on the overlapping surface, and using the resin laying equipment to level the resin layer; the overlapping area after laying is the welding area;

[0061] S2. Divide the welding area into small areas;

[0062] S3, extract features from small areas;

[0063] The feature extraction method is as follows: using a 3D scanner to scan each small area and extract features including flatness, thickness and curvature;

[0064] S4, constructing a speed mapping table according to the extracted different features;

[0065] S5, planning the laser scanning path according to the speed mapping table;

[0066] Further: wherein the size of the small area is a square with a side length of 10 mm to 50 mm or a circle with a diameter of 10 mm to 50 mm;

[0067] Further: The flatness calculation method is: calculate the standard deviation based on the surface height data of each small area, and the calculation formula is:

[0068] h i It represents the height value measured at the i-th measuring point when performing three-dimensional scanning on a small area. In the welding process, h i The height value reflects the relative height of the titanium alloy plate, carbon fiber reinforced epoxy resin composite plate and the PA6 thermoplastic resin film laid on its surface at the measuring point. It is related to the flatness of the laid resin layer and is used to accurately describe the microscopic undulation of the surface of the welding area.

[0069] It represents the average height, which is the arithmetic mean of the height values ​​of all measuring points in the small area. It is a benchmark value for measuring the surface height of the entire small area. By comparing it with the height value of each measuring point, the degree of height dispersion is calculated to determine the flatness.

[0070] N is the number of measurement points. The more measurement points there are, the more accurate the evaluation of the surface flatness of a small area will be. When extracting features, the number depends on the sampling density setting of the 3D scanner used. High-density sampling can capture the surface features of the welding area more carefully and provide sufficient data support for accurate calculation of flatness.

[0071] σ represents the surface height of the small area relative to the average height The larger the standard deviation, the greater the change in surface height, that is, the worse the flatness; the smaller the standard deviation, the flatter the surface.

[0072] The thickness calculation method is to calculate the average thickness of each small area, and the calculation formula is:

[0073] t i It indicates the thickness value measured at the i-th measuring point when measuring the thickness of a small area. The thickness here refers to the vertical distance from the lap joint of the titanium alloy plate and the carbon fiber reinforced epoxy resin composite plate to its surface, reflecting the actual thickness at different positions in the welding area.

[0074] N represents the number of measuring points, and its meaning is similar to that in the flatness calculation formula. Depending on the sampling setting of the measuring equipment, more measuring points help to obtain a more accurate average thickness value, thus providing a comprehensive understanding of the thickness distribution of the welding area.

[0075] t represents the calculated average thickness, which represents the average thickness of the entire material in the small area.

[0076] The curvature calculation method is to calculate the maximum curvature of each small area, and the calculation formula is:

[0077] z represents the surface height, which is a dimension in the three-dimensional coordinate system that describes the surface shape of the welding area. It is associated with the height measurement in the flatness calculation and is used to describe the degree of curvature of the surface. The change in its value reflects the undulation of the welding area surface in the vertical direction.

[0078] x represents the horizontal coordinate, which is another dimension in the three-dimensional coordinate system. Together with z, it determines the position of each point on the surface of the welding area. By calculating the curvature of the second-order partial derivative of z with respect to x, the curvature change of the surface in the horizontal direction can be accurately described, so as to fully grasp the shape characteristics of the welding area, so as to adjust the laser scanning path and welding speed and other parameters according to the curvature during the welding process, ensure that the laser energy can be evenly distributed in the area with larger curvature, and ensure the consistency of welding quality.

[0079] κ represents the calculated maximum curvature, which characterizes the maximum curvature of the surface in the small area. In welding, changes in curvature will cause changes in the incident angle and energy distribution of the laser on the surface, affecting the melting of the resin and the bonding effect with other materials. Accurate calculation of curvature is conducive to optimizing welding process parameters and ensuring welding quality.

[0080] Further: wherein, the speed mapping table is constructed by:

[0081] Adjust the welding speed according to the flatness. According to the pre-established welding speed database, select the welding speed corresponding to the flatness. When σ>σ1, v f =v1; when σ≤σ1, v f =v2;

[0082] σ1 represents the flatness threshold; v1 represents the welding speed for high flatness; v2 represents the welding speed for low flatness; v f Indicates the welding speed corresponding to the flatness;

[0083] Adjust the welding speed according to the thickness. According to the relationship model between thickness and welding speed, select the welding speed corresponding to the thickness. When t>t1, v t =v3; when t≤t1, v t =v4;

[0084] t1 represents the thickness threshold; v3 represents the welding speed corresponding to thin thickness; v4 represents the welding speed corresponding to thick thickness; v t Expressed as welding speed corresponding to thickness;

[0085] Adjust the welding speed according to the curvature. According to the change curve of curvature and welding speed, select the welding speed corresponding to the curvature. When κ>κ1, v κ =v5; when κ≤κ1, v κ =v6;

[0086] κ1 represents the threshold value of curvature; v5 represents the welding speed of large curvature; v6 represents the welding speed of small curvature; v κ Expressed as the velocity corresponding to the curvature;

[0087] For each small area, by comparing v f 、v t 、v κ The welding speed is determined by the size of the welding speed, and the minimum value is selected as the final welding speed; and a speed mapping table is created using the database management system to record the number, characteristic data and final welding speed of each small area one by one to ensure the integrity and accuracy of the data.

[0088] Further: wherein the laser scanning path planning method is:

[0089] Generate a preliminary scanning path for each small area using the grid method or Dijkstra algorithm to ensure that the path covers the entire small area and minimizes the path length;

[0090] Use path optimization algorithms (such as genetic algorithms, particle swarm optimization algorithms, etc.) to optimize the generated path to ensure that the path is shortest and evenly distributed, and the laser beam can evenly cover the area with large curvature;

[0091] Use a connection algorithm (such as the traveling salesman problem TSP algorithm) to connect the paths of each small area into a complete path, ensure the continuity and integrity of the path, optimize the path connection, and ensure that the total length of the path is the shortest.

[0092] Further: wherein, the welding area is divided into small areas by using CNC cutting or laser marking technology so that the area boundaries are clear and distinct, the transition between adjacent areas is smooth, and the entire welding area is divided without omissions and overlaps.

[0093] Further: short pulse laser and continuous laser are used to work together, so that the laser energy can be precisely focused on the PA6 thermoplastic resin film according to the plan, causing it to heat up and melt quickly, achieving a stable connection of the materials, while strictly controlling the heat affected zone and ensuring high-precision welding, giving full play to the advantages of different materials, and improving the comprehensive performance and durability of the product. Among them, the selected laser can be a laser with a wavelength in the near-infrared range (such as 1064nm).

[0094] Further: Among them, the resolution of the 3D scanner is not less than 0.01mm, the measurement accuracy error is within ±0.005mm, and the scanning process follows the predetermined scanning path and sampling density to ensure the acquisition of comprehensive and accurate data.

[0095] Further: A short pulse laser assisted continuous laser welding device, used to implement the above method, comprising:

[0096] Tooling, used to fix titanium alloy plates and carbon fiber reinforced epoxy resin composite plates to ensure that their lap surfaces are aligned;

[0097] Resin laying equipment, used to evenly lay PA6 thermoplastic resin film on the overlapping surface and level the resin layer;

[0098] 3D scanner, with a resolution of not less than 0.01mm and a measurement accuracy error within ±0.005mm, is used to scan small areas of the welding area and extract features including flatness, thickness and curvature;

[0099] Database management system, used to store welding speed database and generate speed mapping table, and perform computational tasks such as feature extraction, speed mapping table construction and laser scanning path planning;

[0100] CNC cutting or laser marking equipment: used to accurately divide the welding area into multiple small areas, ensuring clear and distinct area boundaries, smooth transitions between adjacent areas, and no omissions or overlaps in the entire welding area;

[0101] Laser welding equipment, including short-pulse laser sources and continuous laser sources, as well as laser beam guiding and control devices, can efficiently weld the welding area according to the planned laser scanning path.

[0102] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0103] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example.

[0104] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may alter, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A short pulse laser assisted continuous laser welding method, characterized in that: The following steps are involved: S1. Laying the materials; the laying method is: placing the titanium alloy plate and the carbon fiber reinforced epoxy resin composite material plate on the tooling so that the overlapping surfaces are completely aligned, then evenly laying the PA6 thermoplastic resin film on the overlapping surface, and using the resin laying equipment to level the resin layer; the overlapping area after laying is the welding area; S2. Divide the welding area into small areas; S3, extract features from small areas; The feature extraction method is as follows: using a 3D scanner to scan each small area and extract features including flatness, thickness and curvature; S4, constructing a speed mapping table according to the extracted different features; S5. Plan the laser scanning path according to the speed mapping table.

2. A short pulse laser assisted continuous laser welding method according to claim 1, characterized in that: in, The size of the small area is a square with a side length of 10mm to 50mm or a circle with a diameter of 10mm to 50mm.

3. A short pulse laser assisted continuous laser welding method according to claim 1, Features: The flatness calculation method is: calculate the standard deviation based on the surface height data of each small area, and the calculation formula is: h i It represents the height value measured at the i-th measuring point when performing three-dimensional scanning on a small area; represents the average height, that is, the arithmetic mean of the height values ​​of all measuring points in the small area; N is the number of measuring points; σ represents the surface height of the small area relative to the average height The degree of dispersion; The thickness calculation method is to calculate the average thickness of each small area, and the calculation formula is: t i It indicates the thickness value measured at the i-th measuring point when measuring the thickness of a small area; N indicates the number of measuring points; t indicates the calculated average thickness; The curvature calculation method is to calculate the maximum curvature of each small area, and the calculation formula is: z represents the surface height; x represents the horizontal coordinate; κ represents the calculated maximum curvature.

4. A short pulse laser assisted continuous laser welding method according to claim 1, characterized in that: in, The speed mapping table is constructed as follows: Adjust the welding speed according to the flatness. According to the pre-established welding speed database, select the welding speed corresponding to the flatness. When σ>σ1, v f =v1; when σ≤σ1, v f =v2; Adjust the welding speed according to the thickness. According to the relationship model between thickness and welding speed, select the welding speed corresponding to the thickness. When t>t1, v t =v3; when t≤t1, v t =v4; Adjust the welding speed according to the curvature. According to the change curve of curvature and welding speed, select the welding speed corresponding to the curvature. When κ>κ1, v κ =v5; when κ≤κ1, v κ =v6; For each small area, by comparing v f 、v t 、v κ The welding speed is determined by the size of the welding speed, and the minimum value is selected as the final welding speed; and a speed mapping table is created using the database management system to record the number, characteristic data and final welding speed of each small area one by one.

5. A short pulse laser assisted continuous laser welding method according to claim 1, Features: Among them, the laser scanning path planning method is: Using the grid method, a preliminary scanning path for each small area is generated to ensure that the path covers the entire small area and minimizes the path length; Using the path optimization algorithm, the generated path is optimized to ensure that the path is the shortest and evenly distributed, and the laser beam can evenly cover the area with large curvature; The connection algorithm is used to connect the paths of each small area into a complete path to ensure the continuity and integrity of the path.

6. A short pulse laser assisted continuous laser welding method according to claim 1, characterized in that: in, The welding area is divided into small areas by using CNC cutting or laser marking technology to make the area boundaries clear and definite, the transition between adjacent areas is smooth, and there is no omission or overlapping division of the entire welding area.

7. The short pulse laser assisted continuous laser welding method according to claim 1, characterized in that: in, The resolution of the 3D scanner is no less than 0.01mm, and the measurement accuracy error is within ±0.005mm. The scanning process follows the predetermined scanning path and sampling density to ensure comprehensive and accurate data.

8. A short pulse laser assisted continuous laser welding device, used to implement the method according to any one of claims 1 to 7, characterized in that: include: Tooling, used to fix titanium alloy plates and carbon fiber reinforced epoxy resin composite plates to ensure that their lap surfaces are aligned; Resin laying equipment, used to evenly lay PA6 thermoplastic resin film on the overlapping surface and level the resin layer; 3D scanner, with a resolution of not less than 0.01mm and a measurement accuracy error within ±0.005mm, is used to scan small areas of the welding area and extract features including flatness, thickness and curvature; A database management system is used to store the welding speed database and generate speed mapping tables, as well as perform feature extraction, speed mapping table construction and laser scanning path planning calculation tasks; CNC cutting or laser marking equipment: used to accurately divide the welding area into multiple small areas, ensuring clear and distinct area boundaries, smooth transition between adjacent areas, and no omissions or overlaps in the entire welding area; Laser welding equipment, including short-pulse laser sources and continuous laser sources, as well as laser beam guiding and control devices, can efficiently weld the welding area according to the planned laser scanning path.

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