Laser welding method and device for aero-engine assembly

Abstract

The invention relates to the technical field of laser welding, and discloses an aero-engine assembly laser welding method and equipment, and the method comprises the steps that a to-be-welded area is detected, geometrical morphology data of the area is generated, and the geometrical morphology data comprises the size, curvature and surface state of the welding area; a preheating light beam is emitted, according to the geometrical morphology data, the focus diameter of the preheating light beam is adjusted, a preheating area is formed, the area to be welded is preheated, the power and irradiation time of the preheating light beam are controlled through real-time feedback, a welding light beam is started, a welding area is formed, and welding is conducted in the preheating area, and heat preservation light beams are synchronously emitted, a heat preservation area is formed around the welding area, and heat map information in the welding process is monitored in real time. According to the laser welding method and device for the aero-engine assembly, the temperature distribution of the welding area is uniform, the temperature gradient of materials is controlled in the welding process, large thermal stress is avoided, and the welding quality is improved.

Description

Technical Field

[0001] The invention relates to the technical field of laser welding, and in particular to a laser welding method and equipment for aircraft engine components. Background Art

[0002] Aircraft engines are the core power units of modern aircraft, and their performance directly affects the safety, reliability and economy of aircraft. As an important part of aircraft engines, the combustion chamber casing is subjected to extremely high temperatures and pressures, and is required to have excellent heat resistance, strength and oxidation resistance. In order to meet this series of stringent requirements, the combustion chamber casing is usually made of high-temperature alloys (such as nickel-based alloys) or titanium alloys. The welding process of these materials requires extremely high precision and stability. During the welding process, controlling the welding quality and preventing welding defects are the key to ensuring the performance and life of the combustion chamber casing. Any welding defects will seriously affect the overall performance and safety of the engine.

[0003] At present, the laser welding method of aircraft engine components directly uses a laser beam to weld in the area to be welded, and completes the welding process by setting fixed welding parameters (such as welding power, welding speed, etc.). In order to avoid thermal stress and deformation generated during the welding process, lower welding power and slower welding speed are usually used in the prior art, which can easily affect the welding efficiency. In addition, the prior art does not have sufficient control over thermal stress, which can easily lead to uneven temperature distribution in the welding area and a large temperature gradient of the material during the welding process, which can easily generate large thermal stress and cause deformation and cracking of the material, affecting the welding quality. Summary of the invention

[0004] The purpose of the present invention is to provide a laser welding method and equipment for aircraft engine components, so as to make the temperature distribution of the welding area uniform and control the temperature gradient of the material during the welding process, avoid the generation of large thermal stress, and improve the welding quality.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: Design a laser welding method for aircraft engine components, including: S100, inspecting the area to be welded and generating geometric shape data of the area, wherein the geometric shape data includes the size, curvature and surface state of the welding area; S200, emitting a preheating beam, adjusting the focal diameter of the preheating beam according to the geometric shape data, forming a preheating area, preheating the area to be welded, and controlling the power and irradiation time of the preheating beam through real-time feedback; S300, starting a welding beam to form a welding area, so that welding is performed in the preheating area, wherein during the welding process, a heat preservation beam is synchronously emitted to form a heat preservation area around the welding area, and heat map information during the welding process is monitored in real time, and the power and position range of the heat preservation beam are dynamically adjusted according to the heat map information; S400. After welding is completed, the weld is subjected to nondestructive testing to obtain the test results. Based on the test results, the coordination mode and power configuration of the preheating, welding and insulation beams are optimized.

[0006] Optionally, the S100 specifically includes: S110, clean the area to be welded and remove the oxide layer, oil stains and other impurities on the surface; S120, using a 3D laser scanner to scan the cleaned area to be welded, collecting 3D point cloud data, and adjusting the relative position between the scanner and the area to be welded during the scanning process to ensure that the scanning covers the entire area to be welded; S130, preprocessing the collected three-dimensional point cloud data, removing noise and redundant points, generating a three-dimensional geometric model of the area to be welded, extracting geometric features of the area to be welded, the geometric features including size, curvature and surface state, obtaining geometric morphology data, verifying the extracted geometric morphology data, and importing the verified geometric morphology data into a welding control system.

[0007] Optionally, the step 130 specifically includes: S131, using a filtering algorithm to process the collected three-dimensional point cloud data, removing noise and redundant points, and generating a three-dimensional geometric model of the area to be welded through three-dimensional modeling; S132, obtaining the size of the area to be welded by calculating the outer boundaries of the geometric model in all directions, obtaining the surface state of the area to be welded by collecting surface height data of the area to be welded and calculating the average value of the surface height data of the area to be welded by using a statistical method, determining a fitting neighborhood in the neighborhood of each point of the three-dimensional geometric model, and fitting the three-dimensional point cloud data in the fitting neighborhood by using a least squares method; S133, fitting a local surface to obtain a fitted local surface, calculating the principal curvature of the point through the fitted local surface to obtain the curvature, and obtaining geometric shape data through integration; S134, comparing and verifying the geometric shape data with a preset standard model, performing error analysis, obtaining that the geometric shape data is within an error range, and importing the verified geometric shape data into a welding control system.

[0008] Optionally, the S200 specifically includes: S210, starting the preheating beam emitting device to emit the preheating beam, preliminarily calibrating the power and irradiation time of the preheating beam, setting the focal diameters of different parts of the area to be welded according to the curvature information in the extracted geometric morphology data, setting a relatively small focal diameter for the area to be welded with a larger surface curvature, and setting a relatively large focal diameter for the area to be welded with a smaller curvature, irradiating the preheating beam to the area to be welded, and forming a preheating area; S220, start the temperature monitoring system, monitor the temperature change of the area to be welded in real time, obtain temperature distribution data, adjust the power and focus diameter of the preheating beam according to the temperature distribution data feedback, and optimize the focus diameter according to the temperature distribution data; S230. Confirm the effect of the focal diameter and power adjustment of the preheating beam through a feedback control system, so that the preheating area stably and evenly covers the area to be welded, and the temperature should be evenly distributed in the predetermined area.

[0009] Optionally, the S300 specifically includes: S310, emitting a welding beam, setting the power of the welding beam, setting the focal diameter of the welding beam according to the geometric shape data, irradiating the welding beam to the preheating area, and forming a welding area; S320, emitting a heat preservation beam synchronously with the emitting welding beam, setting the power, distribution shape and position range of the heat preservation beam according to the geometric shape data, and forming a heat preservation area around the welding area; S330, using a heat map monitoring system, collecting data of the welding area, the insulation area, and materials around the insulation area in real time during the welding process to obtain heat map information; S340, dynamically adjust the power and position range of the insulation beam through the welding control system according to the heat map information.

[0010] Optionally, the distribution shape of the heat preservation light beam includes a multi-segment ring-shaped light beam or a longitudinal strip-shaped light beam or a dot-shaped light beam; The distribution shape of the heat preservation light beam is selected according to the geometric shape data, and the selected distribution shape is used as the preliminary mode of the light source module.

[0011] Optionally, the S340 specifically includes: S341, when the distribution shape of the heat preservation light beam is set to a lattice light beam; S342. According to the heat map information, for areas where the temperature changes rapidly, the density of the dot-shaped beams of the heat preservation beams is increased, and the spacing between the dot-shaped beams is reduced; for areas where the temperature changes slowly, the density of the dot-shaped beams is reduced, and the spacing between the dot-shaped beams is increased; S343. Increase the dot-matrix beam power in the lower temperature area and reduce the dot-matrix cross beam power in the higher temperature area.

[0012] Optionally, the S330 specifically includes: S331, start a heat map monitoring system, wherein the heat map monitoring system includes an infrared thermal imager and a temperature sensor, and collects data of the welding area, the insulation area, and the materials around the insulation area in real time; S332. Integrate the temperature data collected by the temperature sensor and the image data captured by the infrared thermal imager to generate heat map information to display the temperature distribution.

[0013] Optionally, the heat map information includes the temperature values ​​of the welding area, the insulation area and the surrounding materials during the welding process, the boundary lines of the temperature zones and the rate of change over time, which is used to determine the uniformity of the temperature distribution and whether there is a large temperature gradient.

[0014] An aerospace engine component laser welding device, using the aerospace engine component laser welding method as described above, comprises: A detection component is used to scan the area to be welded and generate geometric shape data of the area; A welding assembly, the welding assembly comprising a welding mechanism and a heat preservation mechanism, the welding mechanism is used to emit a preheating beam and a welding beam, and the heat preservation mechanism is used to emit a heat preservation beam; The temperature monitoring mechanism is used to collect temperature data of the area to be welded and the surrounding materials during the welding process in real time to generate heat map information.

[0015] The present invention provides a method and device for laser welding of aircraft engine components, which have the following beneficial effects: The laser welding method and equipment for aircraft engine components ensures a full understanding of the welding area before welding through geometric morphology data detection, thereby providing precise parameters for subsequent preheating and welding (i.e., for adjusting the focal diameter of preheating and welding), avoiding welding defects caused by uneven surface conditions of the material, preheating the area to be welded by a preheating beam, and adjusting the power and focal diameter of the beam by a real-time feedback mechanism to ensure the uniformity of preheating, which not only helps to reduce the thermal stress in the initial stage of welding, but also prevents material deformation caused by excessive temperature gradient in the welding area. During the welding process, a heat preservation beam is emitted at the same time and the heat map information is monitored in real time, and the power and position range of the heat preservation beam are dynamically adjusted to ensure uniform temperature distribution around the welding area, effectively reducing cracking and deformation of the material around the welding area due to thermal stress during welding, and improving the overall quality and reliability of welding. After welding is completed, the weld quality is evaluated by a non-destructive testing method. After obtaining the test results, the collaborative mode and power configuration of the preheating, welding and heat preservation beams are optimized to further improve the welding quality, consistency and reliability, thereby providing the final performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0017] The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with this technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantive technical significance. Any structural modification, change in proportion or adjustment of size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical contents disclosed by the present invention.

[0018] Figure 1 This is one of the flow diagrams of the laser welding method for aircraft engine components of Example 1. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. All other embodiments obtained by ordinary technicians in the field without making creative work based on the embodiments of the present invention shall fall within the scope of protection of the present invention.

[0020] See also Figure 1 The present invention provides a technical solution: a laser welding method for aircraft engine components, comprising: S100, inspecting the area to be welded and generating geometrical morphological data of the area, the geometrical morphological data including the size, curvature and surface state of the welding area. In the initial stage of laser welding of aircraft engine components, the area to be welded is inspected and the geometrical morphological data of the area is generated to obtain detailed information on the size, curvature and surface state of the welding area. Accurate measurement of the size helps determine the amount of material required for welding and the range of action of the light beam. Detection of the curvature obtains the shape characteristics of the welding area, while the surface state, such as surface roughness and flatness, affects the absorption and reflection of the welding light beam and the welding effect. The physical characteristics of the area to be welded can be grasped through the geometrical morphological data, providing data support for subsequent preheating and welding operations. S200, emitting a preheating beam, adjusting the focal diameter of the preheating beam according to the geometric shape data, forming a preheating area, preheating the area to be welded, controlling the power and irradiation time of the preheating beam through real-time feedback, emitting the preheating beam and adjusting its focal diameter according to the generated geometric shape data to form a uniform preheating area, during the irradiation process of the preheating beam, monitoring and adjusting the power and irradiation time of the beam through a real-time feedback control system, so that the preheating beam adapts to the geometric characteristics of the welding area, and ensuring uniform energy distribution of the preheating beam through real-time adjustment to avoid local overheating or overcooling, thereby reducing thermal stress and material deformation, and providing thermodynamic conditions for the welding process; S300, start the welding beam to form a welding area, so that welding is performed in the preheating area, wherein during the welding process, a heat preservation beam is synchronously emitted to form a heat preservation area around the welding area, the heat map information during the welding process is monitored in real time, and the power and position range of the heat preservation beam are dynamically adjusted according to the heat map information. During the welding process, in order to ensure the welding quality and reduce thermal stress, a heat preservation beam is synchronously emitted to form a heat preservation area around the welding area, and the heat map information during the welding process is monitored in real time, and the power and position range of the heat preservation beam are dynamically adjusted to ensure uniform temperature distribution, avoid local overheating or too fast cooling, and avoid large temperature gradients; S400. After welding is completed, perform nondestructive testing on the weld to obtain the test results. According to the test results, optimize the coordination mode and power configuration of the preheating, welding and insulation beams. The nondestructive testing method may include ultrasonic testing or X-ray testing to ensure the integrity and quality of the weld. According to the test results, analyze the defects and problems in the weld, and optimize and adjust the coordination mode and power configuration of the preheating, welding and insulation beams. Through feedback and optimization, continuous improvement is made to ensure the stability and reliability of welding quality and improve welding efficiency and effect.

[0021] S100 specifically includes: S110. Clean the area to be welded, remove the oxide layer, oil and other impurities on the surface, clean the area to be welded, avoid surface pollutants that may affect the welding quality, pollutants in the area to be welded may cause weld instability and welding defects, clean the welding area by using detergents and mechanical methods (such as brushes, sandpaper, or chemical solvents), make the surface of the welding area smooth and clean, and provide a good foundation for scanning and welding operations; S120, use a 3D laser scanner to scan the cleaned area to be welded, collect 3D point cloud data, adjust the relative position of the scanner and the area to be welded during the scanning process, and ensure that the scanning covers the entire area to be welded. During the 3D laser scanning process, the relative position of the scanner and the area to be welded needs to be continuously adjusted to ensure that all areas are completely covered without omission, and ensure that the collected data accurately reflects the actual shape and surface features of the welding area, and these data are used for subsequent geometric feature extraction and analysis; S130, preprocessing the collected 3D point cloud data, removing noise and redundant points, generating a 3D geometric model of the area to be welded, extracting geometric features of the area to be welded, the geometric features including size (such as length, width, thickness), curvature (such as curvature radius) and surface state (such as surface roughness), obtaining geometric morphology data, verifying the extracted geometric morphology data, importing the verified geometric morphology data into the welding control system, providing a reference position for preheating and welding, first preprocessing the collected 3D point cloud data, using a filtering algorithm (such as Gaussian filtering, statistical filtering, etc.) to remove noise The three-dimensional geometric model of the area to be welded is generated through surface reconstruction and triangulated meshing technology. Next, the geometric features of the welding area are extracted, including size (such as length, width, thickness), curvature (such as curvature radius) and surface state (such as surface roughness). These geometric morphology data will be verified by comparing with the standard model and error analysis to ensure the data is accurate. Finally, the verified geometric morphology data will be imported into the welding control system to provide a reference position for preheating and welding, ensuring precise control of the welding process and high-quality output.

[0022] 130 specifically includes: S131, using a filtering algorithm to process the collected 3D point cloud data, remove noise and redundant points, and generate a 3D geometric model of the area to be welded through 3D modeling. Through denoising, abnormal points and redundant points in the data can be eliminated to improve data quality. Subsequently, using 3D modeling technology to convert the processed point cloud data into a 3D geometric model, accurately reflecting the true shape of the area to be welded, and providing a basis for subsequent geometric feature extraction; S132, by calculating the outer boundaries of the geometric model in each direction, the size (i.e., length, width, thickness) of the area to be welded is obtained, by collecting the surface height data of the area to be welded, using a statistical method to calculate the average value of the surface height data of the area to be welded, the surface state (i.e., surface roughness) of the area to be welded is obtained, a fitting neighborhood is determined in the neighborhood of each point of the three-dimensional geometric model, and the three-dimensional point cloud data in the fitting neighborhood is fitted by the least squares method; S133, fitting a local surface to obtain a fitted local surface, calculating the principal curvature of the point through the fitted local surface to obtain the curvature (i.e., the radius of curvature), and obtaining geometric shape data through integration; S134. Compare the geometric data with the preset standard model, perform error analysis, and obtain the geometric data within the error range. Import the verified geometric data into the welding control system to provide a reference position for preheating and welding. By comparison, determine whether the geometric data is within the allowable error range to ensure the reliability of the data. Through error analysis, abnormal values ​​in the data can be discovered and corrected to ensure the accuracy of the data. Import the verified geometric data into the welding control system to provide a reference position for the preheating and welding process. The welding control system uses this data to optimize the welding path, power configuration and other parameters to improve the accuracy and quality of the welding process.

[0023] S200 specifically includes: S210, start the preheating beam emitting device to emit the preheating beam, preliminarily calibrate the power and irradiation time of the preheating beam, set the focal diameters of different parts of the area to be welded according to the curvature information in the extracted geometric morphology data, set a relatively small focal diameter for the area to be welded with a larger surface curvature, and set a relatively large focal diameter for the area to be welded with a smaller curvature, irradiate the preheating beam to the area to be welded to form a preheating area, first start the preheating beam emitting device, emit an initial preheating beam to the area to be welded, and in order to ensure the accuracy of the preheating process, first calibrate the power and irradiation time of the preheating beam Step 1 calibration is performed so that the beam can evenly cover the area to be welded and achieve the required preliminary preheating effect. According to the curvature information in the geometric morphology data extracted in the previous step, the focus diameter is set for different parts of the area to be welded. For areas with large surface curvature, a relatively small focus diameter is selected to ensure that the beam energy is highly concentrated and improve the local heating efficiency; for areas with small surface curvature, a larger focus diameter is set to evenly distribute the beam energy and avoid local overheating. Finally, the adjusted preheating beam is irradiated to the area to be welded to form a preheating area to prepare for the subsequent welding process. S220, start the temperature monitoring system, monitor the temperature change of the area to be welded in real time, obtain temperature distribution data, adjust the power and focal diameter of the preheating beam according to the feedback of the temperature distribution data, and optimize the focal diameter according to the temperature distribution data. The temperature monitoring system obtains the temperature distribution data of the area to be welded through an infrared thermal imager or other sensors, accurately records the temperature of different points in the area, and adjusts the power and focal diameter of the preheating beam according to the real-time feedback of the temperature distribution data. For areas with lower temperatures, more heat is concentrated by increasing the power of the preheating beam or adjusting the focal diameter; for areas with higher temperatures, the beam power is appropriately reduced or the focal diameter is increased to avoid local overheating. Through this dynamic adjustment, the temperature distribution of the area to be welded is ensured to be uniform, and the local temperature is avoided to be too high or too low, thereby improving the preheating effect and welding quality; S230. Confirm the effect of the focal diameter and power adjustment of the preheating beam through the feedback control system, so that the preheating area stably and evenly covers the area to be welded. The temperature should be evenly distributed in the predetermined area. Collect and analyze the temperature distribution data of the area to be welded in real time to ensure that the preheating area stably and evenly covers the entire area to be welded. At this stage, the temperature of the preheating area is evenly distributed in the predetermined area to avoid local overheating or overcooling to prevent welding defects (such as cold cracks, hot cracks, etc.). Once the temperature distribution reaches the expected level and it is confirmed that the preheating area has achieved the required stability and uniformity, make the final adjustment. At this time, make precise final adjustments to the power and focal diameter of the preheating beam to ensure that the subsequent welding process proceeds smoothly and provide suitable temperature conditions for welding to improve welding quality.

[0024] S300 specifically includes: S310, emitting a welding beam, setting the power of the welding beam, setting the focal diameter of the welding beam according to the geometric shape data, irradiating the welding beam to the preheating area to form a welding area, setting the power of the welding beam to ensure that there is enough energy to melt and fuse the engine component materials together, too little power may result in loose welding, and too much power may damage the component, and it is also very important to set the focal diameter of the welding beam according to the geometric shape data of the component, and different geometric shapes and sizes require appropriate focal diameters to ensure that the welding beam can accurately act on the target area, and then irradiating the welding beam to the preheating area, which has been pre-processed to facilitate the smooth progress of the welding process, thereby forming a welding area, and this step lays the foundation for subsequent welding and insulation operations, and appropriate welding parameter settings can improve welding quality, reduce welding defects, and ensure the performance and safety of aircraft engine components; S320, emitting a heat preservation beam synchronously with the emission of the welding beam, setting the power, distribution shape and position range of the heat preservation beam according to the geometric morphology data, and forming a heat preservation area around the welding area. The heat preservation beam forms a heat preservation area around the welding area. On the one hand, it can prevent the welding area from cooling down rapidly after welding, because too fast cooling will cause greater internal stress in the welding part, which may cause defects such as cracks, affecting the service life and reliability of the aircraft engine components. On the other hand, suitable heat preservation can make the material structure of the welding area more uniform, improve the strength and toughness of the welded joint, and ensure that the components can still operate stably in a complex working environment. By accurately setting the distribution shape and position range of the heat preservation beam, accurate heat preservation control can be performed for different welding conditions, which can effectively improve the heat preservation effect; S330. The data of the welding area, the insulation area and the materials around the insulation area are collected in real time during the welding process through the heat map monitoring system to obtain heat map information. The data of the welding area, the insulation area and the materials around the insulation area are collected to obtain heat map information. This information can intuitively reflect the temperature distribution of each area during the welding process. The temperature distribution provides a data basis for subsequent welding quality control and can timely detect the situation where the local temperature is too high or too low during the welding process. S340. Dynamically adjust the power and position range of the insulation beam through the welding control system according to the heat map information. After obtaining the detailed heat map information, the welding control system can dynamically adjust the power and position range of the insulation beam according to the actual temperature distribution. From the power adjustment aspect, when it is monitored that the temperature of a part of the welding area is too low, appropriately increasing the power of the insulation beam can increase the heat input of the area and avoid welding defects caused by insufficient temperature; conversely, if the temperature of a part is too high, reducing the power can prevent material damage caused by overheating. From the position range adjustment aspect, according to the heat map display, the insulation beam is accurately moved to the area that needs insulation, which can ensure that the entire welding area and surrounding materials are in a suitable temperature environment. This dynamic adjustment can further optimize the temperature field during the welding process and make the temperature of the welding area more uniform, thereby improving the welding quality, reducing welding deformation and internal stress, enhancing the overall performance and reliability of aircraft engine components, and meeting the use requirements of aircraft engines under extreme working conditions such as high temperature and high pressure.

[0025] In this embodiment, as a preferred solution, the distribution shape of the heat preservation light beam includes a multi-segment ring-shaped light beam or a longitudinal strip-shaped light beam or a dot-shaped light beam; The distribution shape of the heat preservation beam is selected according to the geometric shape data, and the selected distribution shape is used as the preliminary mode of the light source module; By superimposing multiple segments of annular beams to form a gradient heat preservation field, it is possible to accurately match complex curved surface structures (such as the curved surface of turbine blade roots, special-shaped flange interfaces, or the connection section between the conical combustion chamber casing and the turbine) to achieve circumferentially uniform heat dissipation. For example, when welding blade disk components with varying curvatures, the annular distribution can effectively suppress local heat accumulation caused by geometric mutations and avoid circumferential stress concentration, or achieve circumferentially uniform heat compensation during the welding process of the combustion chamber casing, suppressing the "fish's foot" defect caused by the temperature difference between the start and end points of welding. The thermal field generated by the multi-segment annular beam can guide the solidification direction of the molten pool to be consistent with the main stress direction of the combustion chamber (such as the annular weld at the turbine end), so that the columnar crystals are arranged tangentially, which can improve the high-temperature creep resistance of the welding part of the combustion chamber casing, and the edge of the multi-segment annular beam can form a continuous thermal barrier to reduce the turbulence of the protective gas; Through the gradient insulation field formed by the longitudinal strip-shaped beam, during the welding process of the longitudinal seam of the combustion chamber barrel (i.e. the straight weld of the afterburner) or the plane structure with reinforcing ribs (i.e. the welding of the outer shell cooling ribs), the length direction of the longitudinal strip beam is parallel to the welding direction, which can synchronously compensate for the longitudinal shrinkage stress. When the assembly gap fluctuates (i.e. the gap varies between 0.1-0.3mm), the strip width can be dynamically expanded to 1.5-3mm, and the gap is filled by the edge heat flow to avoid the defect of unfusion. The longitudinal strip beam can form a width gradient transition zone; Through the gradient insulation field formed by the dot-shaped beam, in the process of welding ultra-thin combustion chamber wall plates (i.e., high-temperature alloys with a thickness of 0.3-0.8mm) or the interface bonding area formed by connecting multiple materials (i.e., ceramic-based composite materials and high-temperature alloys), taking the ultra-thin combustion chamber wall plates (i.e., alloys with a thickness of 0.3-0.8mm) as an example, when the dot-shaped beam spacing is 0.2-0.5mm, the heat input density is reduced, which can prevent the thin wall from burning through, and is suitable for 0.3mm-level combustion chamber tail nozzle welding. Taking the interface bonding area formed by connecting multiple materials (i.e., ceramic-based composite materials and high-temperature alloys) as an example, the gap of the dot-shaped beam can provide a release path for residual stress, which can reduce the welding crack rate of the ceramic-based composite material shell; In the beam selection process, multi-segment ring-shaped beams are given priority for curved surfaces / annular structures (i.e., circumferential welds of the flame tube or the connection section between the outer casing of the conical combustion chamber and the turbine), lattice beams are used for dissimilar materials / thin walls (i.e., the connection between titanium alloy and ceramics), and longitudinal strips are used for long straight welds / reinforcement ribs (i.e., longitudinal seams of the cylinder). Taking the welding of the conical combustion chamber as an example, the straight edge section of the cone uses a longitudinal strip-shaped beam, and the curved edge section is switched to a multi-segment ring-shaped beam. The beams can be quickly switched and used together. Combined with the heat map information, when local overtemperature is detected, the ring-shaped beam is switched to a lattice beam, forming a "shape-power" dual closed-loop control.

[0026] S340 specifically includes: S341. When the distribution shape of the heat preservation beam is set to a dot-matrix beam, the dot-matrix beam means that the beam will be distributed in the form of multiple points instead of continuous beam irradiation, which can more accurately control the distribution of heat and avoid heat concentration at a certain point, resulting in local overheating or overcooling. The dot-matrix distribution can provide higher flexibility for temperature regulation at each point and make the heat distribution in the heat preservation area more uniform, which helps to maintain the stability and uniformity of temperature during welding; S342. According to the heat map information, for areas with faster temperature changes, increase the density of the dot-matrix beam of the insulation beam and reduce the spacing between the dot-matrix beams. For areas with slower temperature changes, reduce the density of the dot-matrix beam and increase the spacing between the dot-matrix beams. When the temperature in certain areas changes rapidly during welding, more heat input is required to quickly restore temperature uniformity. Therefore, increase the density of the dot-matrix beam and reduce the spacing between points so that more beams can irradiate the area, thereby accelerating its temperature recovery. For areas with slower temperature changes, the heat is already more uniform. Reducing the density of the insulation beam and increasing the point spacing can avoid overheating. This dynamic adjustment can optimize heat distribution according to the thermal changes in different areas to ensure temperature stability during welding; S343. Increase the power of the dot-matrix beam in the area with lower temperature, and reduce the power of the dot-matrix cross beam in the area with higher temperature. For the area with lower temperature, increase the power of the dot-matrix beam to provide more heat to raise the temperature of the area, so that the temperature of the entire welding area is more uniform. For the area with higher temperature, reduce the power output of the dot-matrix beam to avoid overheating and prevent welding defects such as excessive melting or excessive expansion of metal. This method of dynamically adjusting the beam power according to temperature changes can ensure that the entire welding area is within the ideal temperature range, thereby improving welding quality and reducing the occurrence of adverse effects; In the welding of the combustion chamber shell of an aircraft engine, the dot-shaped beam decomposes the continuous heat field into multiple independently controlled micro-areas (i.e., the dot-shaped beam is distributed in a dot-shaped array with a spacing of 0.2-0.5mm) by discrete energy input. It is suitable for thin walls (i.e., 0.3mm-level combustion chamber wall panels) and interface bonding areas formed by the connection of multiple materials (i.e., ceramic-based composite materials and high-temperature alloys). The dot-shaped heat-insulating beam can reduce the heat input density per unit area and avoid burn-through of ultra-thin components. According to the heat map information, for areas with faster temperature changes, the dot density is increased from the conventional 20 points / cm² to 50 points / cm², and the spacing is reduced from 0.5mm to 0.2mm. The high-density dot-shaped coverage suppresses temperature mutations, reducing the width of the heat-affected zone from 1.5mm to 0.8mm. For areas with slower temperature changes, the density is reduced to 10 points / cm² and the spacing is expanded to 1.0mm, reducing redundant heat input and avoiding material grain coarsening caused by thermal diffusion. When adjusting the dot matrix beam power, that is, when a low-temperature area with ΔT≥80℃ is detected, such as the interface bonding area formed by the connection of multiple materials (i.e. ceramic-based composites and high-temperature alloys), the dot matrix power is increased from 500W to 800W, and the formation of the diffusion layer is promoted through local thermal compensation, and the formation of brittle intermetallic compounds is inhibited. When an overheating area with ΔT≤-50℃ is detected (such as around the center of the molten pool), the power is reduced from 800W to 300W, combined with a reduction in the lattice density to form a "thermal barrier".

[0027] S330 specifically includes: S331. Start the heat map monitoring system. The heat map monitoring system includes an infrared thermal imager and a temperature sensor. It collects data on the welding area, the insulation area, and the materials around the insulation area in real time. The infrared thermal imager and the distributed optical fiber temperature sensor work together to reconstruct the three-dimensional thermal field of the welding area. The infrared thermal imager captures the surface radiation heat distribution at a sampling rate of 1000 Hz. The synchronous optical fiber sensor is located on the back of the weld to obtain the internal temperature gradient. An infrared filter with a wavelength of 1.5 μm is used to shield the interference of welding plasma and reduce the temperature measurement error during welding. At this time, in the application of nickel-based single crystal alloy welding, the data of 8 axial temperature measurement points are collected simultaneously with the welding system to construct a thickness direction heat conduction model to accurately predict the grain growth trend of the heat-affected zone. S332. Integrate the temperature data collected by the temperature sensor and the image data captured by the infrared thermal imager to generate heat map information, display the temperature distribution, align the infrared image with the fiber optic temperature data at the sub-pixel level, and establish a temperature field model in a three-dimensional coordinate system. At the same time, when it is detected that the temperature gradient exceeds the critical value (for example, ΔT>300℃ / mm in titanium alloy welding), an early warning is automatically triggered and the potential crack area is marked.

[0028] The heat map information includes the temperature values ​​of the welding area, the insulation area and the surrounding materials during welding, the boundary lines of the temperature areas and the rate of change over time. It is used to determine the uniformity of temperature distribution and whether there is a large temperature gradient. Fiber optic sensors are arranged in the welding area to obtain the temperature values ​​of key points (such as the center of the molten pool and the boundary of the heat-affected zone) at a sampling frequency of 0.1 seconds. The infrared thermal imager is used to scan and generate a temperature gradient image to capture the dynamic changes of the temperature area boundary lines. Through the obtained temperature field model, combined with the heat flow inversion calculation, based on the finite element heat conduction equation, the heat flux density distribution is inferred through the grid nodes to predict the molten pool expansion trend in advance.

[0029] An aerospace engine component laser welding device, using the aerospace engine component laser welding method as described above, comprises: A detection component is used to scan the area to be welded and generate geometric shape data of the area; A welding assembly, the welding assembly comprising a welding mechanism and a heat preservation mechanism, the welding mechanism is used to emit a preheating beam and a welding beam, and the heat preservation mechanism is used to emit a heat preservation beam; The temperature monitoring mechanism is used to collect temperature data of the area to be welded and the surrounding materials during the welding process in real time to generate heat map information.

[0030] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A laser welding method for aircraft engine components, characterized in that: include: S100, inspecting the area to be welded and generating geometric shape data of the area, wherein the geometric shape data includes the size, curvature and surface state of the welding area; S200, emitting a preheating beam, adjusting the focal diameter of the preheating beam according to the geometric shape data, forming a preheating area, preheating the area to be welded, and controlling the power and irradiation time of the preheating beam through real-time feedback; S300, starting a welding beam to form a welding area, so that welding is performed in the preheating area, wherein during the welding process, a heat preservation beam is synchronously emitted to form a heat preservation area around the welding area, and heat map information during the welding process is monitored in real time, and the power and position range of the heat preservation beam are dynamically adjusted according to the heat map information; S400. After welding is completed, the weld is subjected to nondestructive testing to obtain the test results. Based on the test results, the coordination mode and power configuration of the preheating, welding and insulation beams are optimized.

2. The method for laser welding of aircraft engine components according to claim 1, characterized in that: The S100 specifically includes: S110, clean the area to be welded and remove the oxide layer, oil stains and other impurities on the surface; S120, using a 3D laser scanner to scan the cleaned area to be welded, collecting 3D point cloud data, and adjusting the relative position between the scanner and the area to be welded during the scanning process to ensure that the scanning covers the entire area to be welded; S130, preprocessing the collected three-dimensional point cloud data, removing noise and redundant points, generating a three-dimensional geometric model of the area to be welded, extracting geometric features of the area to be welded, the geometric features including size, curvature and surface state, obtaining geometric morphology data, verifying the extracted geometric morphology data, and importing the verified geometric morphology data into a welding control system.

3. The method for laser welding of aircraft engine components according to claim 2, characterized in that: The 130 specifically includes: S131, using a filtering algorithm to process the collected three-dimensional point cloud data, removing noise and redundant points, and generating a three-dimensional geometric model of the area to be welded through three-dimensional modeling; S132, obtaining the size of the area to be welded by calculating the outer boundaries of the geometric model in all directions, obtaining the surface state of the area to be welded by collecting surface height data of the area to be welded and calculating the average value of the surface height data of the area to be welded by using a statistical method, determining a fitting neighborhood in the neighborhood of each point of the three-dimensional geometric model, and fitting the three-dimensional point cloud data in the fitting neighborhood by using a least squares method; S133, fitting a local surface to obtain a fitted local surface, calculating the principal curvature of the point through the fitted local surface to obtain the curvature, and obtaining geometric shape data through integration; S134, comparing and verifying the geometric shape data with a preset standard model, performing error analysis, obtaining that the geometric shape data is within an error range, and importing the verified geometric shape data into a welding control system.

4. The method for laser welding of aircraft engine components according to claim 2, characterized in that: The S200 specifically includes: S210, starting the preheating beam emitting device to emit the preheating beam, preliminarily calibrating the power and irradiation time of the preheating beam, setting the focal diameters of different parts of the area to be welded according to the curvature information in the extracted geometric morphology data, setting a relatively small focal diameter for the area to be welded with a larger surface curvature, and setting a relatively large focal diameter for the area to be welded with a smaller curvature, irradiating the preheating beam to the area to be welded, and forming a preheating area; S220, start the temperature monitoring system, monitor the temperature change of the area to be welded in real time, obtain temperature distribution data, adjust the power and focus diameter of the preheating beam according to the temperature distribution data feedback, and optimize the focus diameter according to the temperature distribution data; S230. Confirm the effect of the focal diameter and power adjustment of the preheating beam through a feedback control system, so that the preheating area stably and evenly covers the area to be welded, and the temperature should be evenly distributed in the predetermined area.

5. The method for laser welding of aircraft engine components according to claim 2, characterized in that: The S300 specifically includes: S310, emitting a welding beam, setting the power of the welding beam, setting the focal diameter of the welding beam according to the geometric shape data, irradiating the welding beam to the preheating area, and forming a welding area; S320, emitting a heat preservation beam synchronously with the emitting welding beam, setting the power, distribution shape and position range of the heat preservation beam according to the geometric shape data, and forming a heat preservation area around the welding area; S330, using a heat map monitoring system, collecting data of the welding area, the insulation area, and materials around the insulation area in real time during the welding process to obtain heat map information; S340, dynamically adjust the power and position range of the insulation beam through the welding control system according to the heat map information.

6. The method for laser welding of aircraft engine components according to claim 5, characterized in that: The distribution shape of the heat preservation light beam includes a multi-segment ring-shaped light beam or a longitudinal strip-shaped light beam or a dot-shaped light beam; The distribution shape of the heat preservation light beam is selected according to the geometric shape data, and the selected distribution shape is used as the preliminary mode of the light source module.

7. The method for laser welding of aircraft engine components according to claim 5, characterized in that: The S340 specifically includes: S341, when the distribution shape of the heat preservation light beam is set to a lattice light beam; S342. According to the heat map information, for areas where the temperature changes rapidly, the density of the dot-shaped beams of the heat preservation beams is increased, and the spacing between the dot-shaped beams is reduced; for areas where the temperature changes slowly, the density of the dot-shaped beams is reduced, and the spacing between the dot-shaped beams is increased; S343. Increase the dot-matrix beam power in the lower temperature area and reduce the dot-matrix cross beam power in the higher temperature area.

8. The method for laser welding of aircraft engine components according to claim 5, characterized in that: The S330 specifically includes: S331, start a heat map monitoring system, wherein the heat map monitoring system includes an infrared thermal imager and a temperature sensor, and collects data of the welding area, the insulation area, and the materials around the insulation area in real time; S332. Integrate the temperature data collected by the temperature sensor and the image data captured by the infrared thermal imager to generate heat map information to display the temperature distribution.

9. The method for laser welding of aircraft engine components according to claim 1, characterized in that: The heat map information includes the temperature values ​​of the welding area, the insulation area and the surrounding materials during the welding process, the boundary lines of the temperature areas and the rate of change over time, which is used to determine the uniformity of the temperature distribution and whether there is a large temperature gradient.

10. A laser welding device for aircraft engine components, characterized in that: The method for laser welding of aircraft engine components according to any one of claims 1 to 9 comprises: A detection component is used to scan the area to be welded and generate geometric shape data of the area; A welding assembly, the welding assembly comprising a welding mechanism and a heat preservation mechanism, the welding mechanism is used to emit a preheating beam and a welding beam, and the heat preservation mechanism is used to emit a heat preservation beam; The temperature monitoring mechanism is used to collect temperature data of the area to be welded and the surrounding materials during the welding process in real time to generate heat map information.

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