Manufacturing method of long blade anti-erosion sheet based on steam turbine

Abstract

The present application relates to the technical field of blade surface protection, in particular to a manufacturing method of a long blade anti-water-erosion sheet based on a steam turbine, comprising the following steps: first, preparing corrosion-resistant alloy powder suitable for laser melting deposition; combining a three-dimensional protection structure model of a blade area to be protected; through improved path planning algorithm, combining differential scanning path combination and interlayer path rotation, completing layer-by-layer high-energy beam flow cladding of the alloy powder; collecting molten pool solidification characteristic information in real time during the cladding stage, dynamically adjusting algorithm control parameters, and in-situ preparing an anti-water-erosion functional body combined with the base material in metallurgy, the functional body having continuous gradient changes in composition and microstructure in the thickness direction. The scheme adapts to the protection requirements of different areas of the blade, improves the cladding forming quality and interface bonding state, and is suitable for the anti-water-erosion protection application of the long blade of the steam turbine.

Description

Technical Field

[0001] This invention relates to the field of blade surface protection technology, and in particular to a method for manufacturing anti-water erosion sheets for long turbine blades. Background Technology

[0002] During long-term operation under wet steam conditions, long turbine blades are continuously subjected to water droplet erosion, which easily leads to surface damage and defects, directly affecting the overall operational stability of the turbine. Currently, the anti-erosion processing of turbine blades mostly employs laser melting deposition technology to fabricate the protective structure. Conventional cladding processes generally use a fixed, single scanning path to complete the overall cladding operation. This path planning lacks specificity and cannot be tailored to the performance requirements of different areas of the protective structure, resulting in limitations in the forming method.

[0003] In existing laser cladding systems, process parameters are mostly kept constant, and the processing lacks real-time monitoring of the molten pool state. Parameter adjustments cannot be made based on dynamic changes during the melting process, resulting in poor controllability of the cladding process. Traditional protective structures maintain consistent internal composition and microstructure, lack gradient design in the thickness direction, and have uniform overall performance distribution, making it difficult to adapt to the differentiated stress and environmental conditions of the blade protection area.

[0004] Under conventional manufacturing methods, the bonding state between the protective structure and the blade substrate is limited, and the residual stress generated during the molding process cannot be effectively dispersed, easily leading to internal structural defects. A standardized cladding molding method is insufficient to meet the molding and manufacturing requirements of complex protective structures, cannot achieve gradient control of the protective structure's performance, and is ill-suited to the long-term water erosion resistance requirements of long turbine blades. Therefore, it is necessary to optimize the cladding path planning mode and process control methods to improve the overall molding state and comprehensive performance of the protective structure. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and propose a method for manufacturing anti-water erosion sheets for long turbine blades.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a method for manufacturing anti-water erosion sheets for long turbine blades, comprising: Prepare corrosion-resistant alloy powder suitable for laser melting deposition process; On the surface of the area to be protected on the turbine blade substrate, based on a preset three-dimensional protective structure model, an improved path planning algorithm is used to control a high-energy beam to perform layer-by-layer scanning and cladding of the corrosion-resistant alloy powder. During the cladding process, the solidification characteristics of the molten pool are collected in real time; Based on the fusion characteristic information, the control parameters of the improved path planning algorithm are dynamically adjusted to manufacture in situ a water erosion resistant functional body that is metallurgically bonded to the blade substrate. The improved path planning algorithm plans multiple cladding path combinations with different scanning strategies based on the water erosion resistance requirements at different locations in the three-dimensional protective structure model, and performs path rotation between layers. The water erosion resistant functional body has a continuous gradient change in composition and microstructure in the thickness direction of the three-dimensional protective structure model.

[0007] As a further aspect of the present invention, the preparation of corrosion-resistant alloy powder suitable for laser melting deposition process includes: Select at least one of cobalt-based alloys, nickel-based alloys, or iron-based alloys as the base powder; Carbide-forming element powder and rare earth element powder are added to the base powder. The carbide-forming element powder includes tungsten carbide, chromium carbide or vanadium carbide, and the rare earth element powder includes yttrium or cerium. A mixed powder comprising base powder, carbide-forming element powder and rare earth element powder is subjected to mechanical alloying treatment. The mechanical alloying treatment is carried out under an inert atmosphere, and the ball milling time is sufficient to allow the carbide-forming element powder and the rare earth element powder to be uniformly embedded in the surface and near-surface layer of the base powder particles. The powder that has undergone mechanical alloying is sieved and dried to obtain the corrosion-resistant alloy powder. The particle size distribution of the corrosion-resistant alloy powder is controlled within a certain range, and the sphericity of the powder meets the preset flowability requirements.

[0008] As a further aspect of the present invention, the step of performing layer-by-layer scanning and cladding of the corrosion-resistant alloy powder on the surface of the area to be protected on the turbine blade substrate, based on a preset three-dimensional protective structure model and using an improved path planning algorithm, comprises: The surface of the area to be protected of the blade substrate is pretreated, and the pretreatment includes cleaning, drying and preheating; The blade substrate is fixed in a forming chamber with multi-axis linkage function, and the transformation relationship between the blade substrate coordinate system and the equipment motion coordinate system is established. Based on the three-dimensional protective structure model, the initial forming layer parameters of the water erosion resistant functional body are set in the improved path planning algorithm. The initial forming layer parameters include the set first laser power and first scanning speed, so as to form a thin-layer bonding area with controlled dilution rate on the surface of the blade substrate. Above the initial forming layer that forms the thin-layer bonding area, the improved path planning algorithm generates cladding paths layer by layer according to the geometric features and performance requirements of different sections of the three-dimensional protective structure model. The high-energy beam melts the corrosion-resistant alloy powder synchronously delivered to the cladding area according to the generated cladding path, and the molten material is deposited and solidified layer by layer.

[0009] As a further aspect of the present invention, the working principle of the improved path planning algorithm includes: Input the digital file of the three-dimensional protective structure model, perform layered slicing on the model, and obtain a series of two-dimensional cross-sectional contours; For each two-dimensional cross-sectional profile, the algorithm assigns a performance level index based on the thickness position of the current two-dimensional cross-sectional profile in the overall model. The performance level index is related to the required hardness and toughness ratio at the corresponding position. Based on the performance level index, the corresponding basic scanning strategy is called from the preset path strategy library. The basic scanning strategy defines a combination of core parameters, including scan line spacing, scan line direction, scan speed, laser power, and beam shape. When applying the basic scanning strategy, the algorithm introduces a path perturbation factor, which is dynamically calculated based on the deviation between the actual morphology and the ideal morphology of the current deposition layer. This factor is used to fine-tune the cladding path of the current layer to compensate for the forming error. After completing the path planning for the current layer, the algorithm applies an interlayer path rotation angle to the path planning for the next deposition layer. The interlayer path rotation angle is optimized based on the simulation results of the residual stress distribution of the current layer in order to reduce the overall forming stress.

[0010] As a further aspect of the present invention, the real-time acquisition of molten pool solidification characteristic information during the cladding process includes: A coaxial vision monitoring system was used to acquire dynamic images of the molten pool area; The dynamic image is processed to extract the solidification feature information, which includes the geometric dimensions of the molten pool, the solidification line morphology at the tail of the molten pool, and the morphology and intensity distribution of the plasma plume on the surface of the molten pool. Infrared thermometers were used to measure the temperature field distribution of the molten pool and its adjacent heat-affected zone in real time. The actual operating parameters of the high-energy beam are recorded synchronously, including real-time laser power, scanning speed, and powder feeding rate.

[0011] As a further aspect of the present invention, the control parameters of the improved path planning algorithm are dynamically adjusted based on the melting and solidification characteristic information, including: The geometric dimensions of the molten pool extracted in real time are compared with the ideal molten pool dimensions preset for the current layer. If the size deviation exceeds the allowable threshold, a power adjustment command or a speed adjustment command is generated and fed back to the improved path planning algorithm. The improved path planning algorithm updates the laser power setting value or scanning speed setting value at subsequent path points online accordingly. Analyze the solidification line morphology at the tail of the molten pool to determine whether there is abnormal grain growth or defect initiation tendency. If there is an abnormal tendency, trigger the path replanning instruction. The improved path planning algorithm temporarily inserts a compensation scan line segment with a specific direction in the subsequent path to improve the local thermal cycling conditions. Based on the morphology and intensity distribution of the plasma plume on the surface of the molten pool, the evaporation loss of alloying elements and the stability of energy absorption inside the molten pool are evaluated. If the evaluation results show instability, a beam morphology adjustment command is generated to dynamically adjust the defocusing amount or spot pattern of the high-energy beam.

[0012] As a further aspect of the present invention, the water erosion resistant functional body has a continuous gradient change in composition and microstructure in the thickness direction of the three-dimensional protective structure model, which is achieved in the following way: At the beginning of the manufacturing process, the powder feeding device is controlled to deliver corrosion-resistant alloy powder with a matrix phase content that is dominant, so as to form a bottom layer region with matching strength and toughness adjacent to the blade substrate in the water erosion resistant functional body. As the number of cladding layers increases toward the outermost edge of the blade inlet, the improved path planning algorithm controls the powder feeding device to continuously and linearly increase the proportion of carbide-forming element powder in the corrosion-resistant alloy powder, while adjusting the laser energy input accordingly to promote the generation and uniform distribution of in-situ carbides. When approaching the outermost surface of the water-erosion resistant functional body, the proportion of carbide-forming element powder in the corrosion-resistant alloy powder reaches its highest level. At the same time, the improved path planning algorithm controls the high-energy beam to adopt a high-power-density and fast-scanning strategy to obtain a fine interdendritic carbide-reinforced, high-hardness surface microstructure. From the bottom layer to the surface layer, the chemical composition, carbide content and type, and grain size of the water erosion resistant functional body all exhibit a continuous gradient transition, with no macroscopic interface.

[0013] As a further aspect of the present invention, the method further includes performing in-situ heat treatment on the anti-water erosion functional body after completing the cladding manufacturing, specifically: When the water erosion cladding of the anti-erosion functional body is completed and the temperature has not yet dropped to room temperature, the ambient temperature inside the forming chamber is controlled to rise to the preset solution treatment temperature range and kept at that temperature for a period of time. After the insulation is completed, the temperature of the control chamber is cooled to the aging treatment temperature range at a programmed rate, and then the insulation is carried out again. After the aging treatment is completed, the entire blade, together with the water erosion resistant functional body, is controlled to be cooled to room temperature at a rate not exceeding the critical cooling rate. The temperature change curve during the in-situ heat treatment process is optimized by partitioning based on the gradient composition of the water erosion resistant functional body, so as to achieve synchronous optimization of the performance of each region of the gradient material.

[0014] As a further aspect of the present invention, the method further includes performing water erosion resistance simulation optimization on the preset three-dimensional protective structure model before cladding manufacturing, specifically: Based on computational fluid dynamics, the impact process of water droplets on the inlet edge of the blades under the operating conditions of a steam turbine was simulated, and the impact velocity, impact frequency and impact angle distribution of water droplets at different positions were obtained as water droplet impact parameters. Based on the water droplet impact parameters, solid mechanics simulation methods are used to calculate the stress distribution, strain energy density, and potential material loss rate of the three-dimensional protective structure model under different thicknesses and different surface configurations. With the optimization objectives of minimizing material loss rate and maximizing impact fatigue life, and with manufacturability as a constraint, the thickness distribution, surface curvature, and transition profile with the substrate of the three-dimensional protective structure model are iteratively optimized. The optimized model geometry data is output as the final preset three-dimensional protective structure model used to control the cladding manufacturing process.

[0015] As a further aspect of the present invention, the method further includes quality prediction and traceability of the water erosion resistant functional body based on cladding manufacturing process data, specifically: The control parameters of the improved path planning algorithm for each layer during the cladding process are recorded, along with the real-time collected fusion characteristic information and dynamically adjusted records. The records are associated with the target performance parameters of the corresponding cladding area obtained through water erosion resistance simulation optimization, and a database of the relationship between manufacturing process parameters and local performance is established. After manufacturing is completed, data is extracted from the associated database to first determine the predicted performance of the water erosion resistant functional body at the corresponding spatial location. The predicted performance includes predicted hardness, predicted toughness, and predicted residual stress. Then, a predicted performance distribution map of the corresponding spatial location is generated based on the predicted performance. Each manufactured blade and its water erosion-resistant functional component are assigned a unique identifier, and the predicted performance distribution map, key manufacturing process parameters, and simulation optimization model version information are bound and stored under the unique identifier.

[0016] Compared with the prior art, the advantages and positive effects of the present invention are as follows: Based on the water erosion resistance requirements of different locations in the 3D protective structure model, multiple combinations of cladding paths with different scanning strategies are set up. Path rotation processing is carried out simultaneously between layers, breaking the fixed single cladding path operation mode and enabling the cladding forming process in different areas to match the corresponding structural forming conditions. During the multi-layer cladding operation stage, the rotation and adjustment of the inter-layer paths changes the heat conduction form during the layer-by-layer stacking process, improves the internal stress distribution of the cladding layer, reduces internal structural anomalies caused by continuous unidirectional scanning, and optimizes the overall consistency of layer-by-layer stacking. The differentiated path planning mode adapts to the forming characteristics of different areas of the protective structure, making the material stacking method in the cladding forming process more reasonable and improving the basic forming architecture of the functional body.

[0017] The entire cladding process collects information on the molten pool's solidification characteristics. Based on real-time monitoring data, the path planning algorithm dynamically adjusts control parameters, enabling dynamic control of the entire cladding process. This adapts to real-time changes in the molten pool's solidification process, maintaining stable progress in high-energy beam scanning cladding operations. The dynamic parameter control mode mitigates the forming fluctuations caused by fixed-parameter processing, stabilizes the powder melting and rapid solidification process, and improves the regularity of layer-by-layer cladding.

[0018] The water-erosion resistant functional body forms a continuous gradient change in composition and microstructure along its thickness direction, eliminating abrupt performance changes between structural layers and smoothing the transition state of the internal microstructure. This gradient microstructure and composition distribution coordinates the metallurgical bonding between the functional body and the blade substrate, weakens the differences in physical properties at the bonding interface, optimizes the mechanical adaptability of the overall structure, mitigates internal structural anomalies caused by interfacial structural incoordination, adapts to long-term operating environments under complex conditions, and enhances the overall structural stability of the protective structure. Attached Figure Description

[0019] Figure 1 This is a flowchart illustrating a method for manufacturing anti-water erosion sheets for long turbine blades according to the present invention. Figure 2 A flowchart for preparing corrosion-resistant alloy powders suitable for laser melting deposition processes; Figure 3 A flowchart illustrating the process of controlling a high-energy beam to perform layer-by-layer scanning cladding of corrosion-resistant alloy powder. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0021] In the description of this invention, it should be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, in the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0022] See Figure 1 This invention provides a method for manufacturing anti-water erosion plates for long turbine blades, the overall implementation of which includes: A corrosion-resistant alloy powder suitable for laser melting deposition process was prepared. On the surface of the area to be protected on a turbine blade substrate, based on a pre-defined three-dimensional protective structure model, an improved path planning algorithm was used to control a high-energy beam to scan and clad the corrosion-resistant alloy powder layer by layer. During this cladding process, the melting and solidification characteristics of the molten pool were collected in real time. Based on the real-time collected melting and solidification characteristics, the control parameters of the improved path planning algorithm were dynamically adjusted, thereby enabling the in-situ fabrication of a water-erosion-resistant functional body that is metallurgically bonded to the blade substrate. The improved path planning algorithm plans multiple combinations of cladding paths with different scanning strategies based on the water-erosion resistance requirements at different locations in the three-dimensional protective structure model, and rotates the path between deposition layers. The final manufactured water-erosion-resistant functional body exhibits a continuous gradient change in composition and microstructure along the thickness direction of the three-dimensional protective structure model.

[0023] In one embodiment of the present invention, when preparing corrosion-resistant alloy powder suitable for laser melting deposition process, refer to... Figure 2 At least one of cobalt-based alloys, nickel-based alloys, or iron-based alloys is selected as the base powder. Carbide-forming element powder and rare earth element powder are added to the base powder. The added carbide-forming element powder includes tungsten carbide, chromium carbide, or vanadium carbide, and the added rare earth element powder includes yttrium or cerium. The mixed powder containing the base powder, carbide-forming element powder, and rare earth element powder is subjected to mechanical alloying treatment. This mechanical alloying treatment is carried out under an inert atmosphere, and the ball milling time is sufficient to allow the carbide-forming element powder and the rare earth element powder to be uniformly embedded in the surface and near-surface layer of the base powder particles. The powder after mechanical alloying treatment is sieved and dried to obtain the corrosion-resistant alloy powder. The particle size distribution of the corrosion-resistant alloy powder is controlled within a certain range, and the sphericity of the powder is ensured to meet the preset flowability requirements.

[0024] In practical implementation, the preparation of corrosion-resistant alloy powder is a preliminary material preparation step in the laser melting deposition process. The quality of the corrosion-resistant alloy powder directly affects the stability of the subsequent cladding process and the performance of the final water-erosion-resistant functional body. In practical implementation, at least one of cobalt-based alloys, nickel-based alloys, or iron-based alloys is selected as the base powder. The chemical composition of the base powder must meet the requirements of high-temperature corrosion resistance and basic toughness. In some embodiments, the base powder can be cobalt-based Stellite 6 alloy powder; in other embodiments, the base powder can also be nickel-based Inconel 625 alloy powder. Carbide-forming element powder and rare earth element powder are added to the base powder. The carbide-forming element powder includes tungsten carbide, chromium carbide, or vanadium carbide, and the rare earth element powder includes yttrium or cerium. The purpose of adding carbide-forming element powder is to form a hard reinforcing phase in situ during the subsequent cladding process, while the addition of rare earth element powder aims to refine the grains and purify the molten pool. Optionally, the carbide-forming element powder can be a mixture of tungsten carbide and chromium carbide powder, and the rare earth element powder can be yttrium powder. The proportions added are pre-calculated and weighed based on the gradient components required for the final water-resistant functional body.

[0025] In practice, a mechanical alloying process is performed on a mixed powder comprising base powder, carbide-forming element powder, and rare earth element powder. This mechanical alloying is carried out in a high-energy ball mill under an inert atmosphere, typically argon or nitrogen, to prevent oxidation of the powder during prolonged milling. The milling time is sufficient to allow the carbide-forming element powder and rare earth element powder to uniformly embed into the surface and near-surface layer of the base powder particles. The milling time is determined by the mill speed, ball-to-powder ratio, and the composite state of the target powder. It is understood that the purpose of mechanical alloying is not to obtain a fully alloyed powder, but rather to ensure that the added phases firmly adhere to the base powder particles, guaranteeing uniform and stable composition during powder feeding and cladding. The energy input for mechanical alloying is... It can be done through the formula:

[0026] in: For equipment-related coefficients, The ball mill speed, For ball grinding time, For the ball-to-material ratio, and This is an empirical index. Optionally, to control the degree of mechanical alloying and prevent excessive cold welding, the ball milling process can be carried out intermittently, i.e., the machine is stopped for cooling after a period of ball milling.

[0027] In some embodiments, the powder that has undergone mechanical alloying treatment needs to be sieved and dried. Sieving is to control the particle size distribution of the corrosion-resistant alloy powder within a certain range, for example, between 45 micrometers and 150 micrometers, to meet the requirements of the laser melting deposition process for powder flowability and uniformity of powder spreading. The drying operation is carried out in a vacuum drying oven or an inert atmosphere-protected drying oven. The drying temperature and time must ensure the removal of adsorbed moisture from the powder to obtain the corrosion-resistant alloy powder. The sphericity of the corrosion-resistant alloy powder must meet the preset flowability requirements, which can be characterized by measuring its flow time using a Hall effect flowmeter. It can be understood that the preparation of the corrosion-resistant alloy powder completes the preparation of a special material suitable for the laser melting deposition process, which combines the corrosion resistance of the matrix with the reinforcing potential of the added phase.

[0028] In one embodiment of the present invention, before cladding the surface of the area to be protected on the turbine blade substrate, refer to... Figure 3 The surface of the area to be protected on the blade substrate is pretreated, including cleaning, drying, and preheating. Then, the blade substrate is fixed in a forming chamber with multi-axis linkage, and a transformation relationship is established between the blade substrate coordinate system and the equipment motion coordinate system. Based on the three-dimensional protective structure model, initial forming layer parameters of the water erosion resistant functional body are set in the improved path planning algorithm. These initial forming layer parameters include a set first laser power and a first scanning speed to form a thin-layer bonding area with controlled dilution rate on the surface of the blade substrate. Above the initial forming layer forming the thin-layer bonding area, cladding paths are generated layer by layer by the improved path planning algorithm according to the geometric characteristics and performance requirements of different sections of the three-dimensional protective structure model. The high-energy beam melts the corrosion-resistant alloy powder synchronously delivered to the cladding area according to the generated cladding paths, and the molten material is deposited and solidified layer by layer.

[0029] The improved path planning algorithm works as follows: The algorithm inputs the digital file of the three-dimensional protective structure model and performs layer-by-layer slicing processing on the model to obtain a series of two-dimensional cross-sectional contours. For each two-dimensional cross-sectional contour, the algorithm assigns a performance level index based on its thickness position in the overall model. This performance level index is related to the required hardness and toughness ratio at the corresponding position. Based on the assigned performance level index, the algorithm calls the corresponding basic scanning strategy from a preset path strategy library. This basic scanning strategy defines a combination of core parameters, including scan line spacing, scan line direction, scan speed, laser power, and beam shape. When applying the basic scanning strategy, the algorithm introduces a path perturbation factor. This factor is dynamically calculated based on the deviation between the actual and ideal morphology of the current deposition layer, and is used to fine-tune the cladding path of the current layer to compensate for forming errors. After completing the path planning for the current layer, the algorithm applies an interlayer path rotation angle to the path planning of the next deposition layer. This interlayer path rotation angle is optimized based on the simulation results of the residual stress distribution of the current layer to reduce overall forming stress.

[0030] In practice, the cladding process on the surface of the turbine blade substrate begins with pretreatment of the area to be protected. This pretreatment includes cleaning with organic solvents to remove oil, followed by drying and preheating of localized areas to a specific temperature to reduce thermal stress. The pretreated blade substrate is then fixed in a forming chamber with multi-axis linkage capabilities. This chamber provides an inert gas protective environment. A precise transformation relationship between the blade substrate coordinate system and the equipment motion coordinate system is established using a combination of optical scanning and a contact probe. This transformation relationship is expressed by a transformation matrix.

[0031] In practical implementation, based on a preset three-dimensional protective structure model, the initial forming layer parameters of the water erosion resistant functional body are set in the improved path planning algorithm. These initial forming layer parameters include a set first laser power and a set first scanning speed. The specific values ​​of the set first laser power and first scanning speed depend on the material properties of the blade substrate and the corrosion-resistant alloy powder. For example, for titanium alloy substrate cladding with cobalt-based alloy powder, the set first laser power can be 800 watts, and the set first scanning speed can be 6 millimeters per second, thereby forming a thin-layer bonding area with controlled dilution rate on the surface of the blade substrate. Above the initial forming layer forming the thin-layer bonding area, the improved path planning algorithm begins to operate. Based on the geometric features and performance requirements of different sections of the three-dimensional protective structure model, the improved path planning algorithm generates cladding paths layer by layer. The high-energy beam melts the corrosion-resistant alloy powder synchronously transported to the cladding area according to the generated cladding paths, and the molten material is deposited and solidified layer by layer.

[0032] The improved path planning algorithm involves data processing and decision-making. It takes a digitized STL file of a 3D protective structure model as input, slices the model into layers with a layer thickness of 0.05 mm, and obtains a series of 2D cross-sectional profiles. For each acquired 2D cross-sectional profile, the algorithm assigns a performance level index based on its thickness position within the overall model. For example, layers closer to the substrate are assigned lower index values, associated with higher toughness requirements, while layers closer to the surface are assigned higher index values, associated with higher hardness requirements. In some embodiments, the performance level index... Calculation and thickness location Related, the relationship is:

[0033] in: This is the starting height. The total height of the water erosion resistant functional body, The total number of preset levels. Based on the calculated performance level index, the improved path planning algorithm calls the corresponding basic scanning strategy from the preset path strategy library. The path strategy library is a database established in advance through experiments. The basic scanning strategy defines the core parameter combination of scan line spacing, scan line direction, scan speed, laser power, and beam shape.

[0034] When applying the basic scanning strategy, the improved path planning algorithm introduces a path perturbation factor to dynamically fine-tune the path. This perturbation factor is dynamically calculated based on the deviation between the actual and ideal morphology of the current deposition layer. Optionally, the actual morphology is characterized by melt channel profile data acquired through an online monitoring system, and the path perturbation factor... The calculation formula is:

[0035] in: To adjust the coefficient, This is the actual height of the melt channel. For the ideal melt flow height, The cladding path width is defined as the path perturbation factor, used to fine-tune the cladding path of the current layer to compensate for forming errors. After completing the path planning for the current layer, the improved path planning algorithm applies an interlayer path rotation angle to the path planning of the next deposition layer. This interlayer path rotation angle is optimized based on the simulation results of the residual stress distribution in the current layer. It can be understood that the residual stress distribution is predicted using a finite element rapid simulation module based on thermo-mechanical coupling, and the improved path planning algorithm selects the angle that results in the most uniform stress distribution from several candidate angles as the interlayer path rotation angle to reduce overall forming stress. In some embodiments, the interlayer path rotation angle is typically selected between 67 degrees and 90 degrees.

[0036] In one embodiment of the present invention, during the cladding process, the solidification characteristic information of the molten pool is acquired in real time. This is achieved by using a coaxial vision monitoring system to acquire dynamic images of the molten pool area. The acquired dynamic images are processed to extract the solidification characteristic information, which includes the geometric dimensions of the molten pool, the solidification line morphology at the tail of the molten pool, and the morphology and intensity distribution of the plasma plume on the surface of the molten pool. Simultaneously, an infrared thermometer is used to measure the temperature field distribution of the molten pool and its adjacent heat-affected zone in real time. The actual operating parameters of the high-energy beam are recorded synchronously, including the real-time laser power, scanning speed, and powder feeding rate.

[0037] Based on the real-time acquired melting and solidification characteristic information, the control parameters of the improved path planning algorithm are dynamically adjusted. The real-time extracted geometric dimensions of the molten pool are compared with the preset ideal molten pool dimensions for the current layer. If the size deviation exceeds the allowable threshold, a power adjustment command or a speed adjustment command is generated and fed back to the improved path planning algorithm. The improved path planning algorithm then updates the laser power setting or scanning speed setting value at subsequent path points online accordingly. The solidification line morphology at the tail of the molten pool is analyzed to determine whether there are abnormal grain growth or defect initiation tendencies. If abnormal tendencies are found, a path replanning command is triggered. The improved path planning algorithm temporarily inserts compensation scanning segments with specific orientations into subsequent paths to improve local thermal cycling conditions. Based on the morphology and intensity distribution of the plasma plume on the molten pool surface, the evaporation loss of alloying elements and energy absorption stability inside the molten pool are evaluated. If the evaluation results show instability, a beam morphology adjustment command is generated to dynamically adjust the defocusing amount or spot pattern of the high-energy beam.

[0038] In practical implementation, information acquisition and dynamic control during the cladding process are crucial. Real-time acquisition of the molten pool's solidification characteristics is a prerequisite for dynamic regulation, and this real-time acquisition is accomplished through a multi-sensor integrated monitoring system. Specifically, a coaxial vision monitoring system is used to acquire dynamic images of the molten pool area. The optical path of the coaxial vision monitoring system is coaxial with the processing laser beam, acquiring image sequences containing the molten pool and its adjacent areas at a frequency of thousands of frames per second. The acquired dynamic images are processed using image processing algorithms for filtering, enhancement, and edge detection, extracting solidification characteristic information. This extracted information includes the geometric dimensions of the molten pool, the solidification line morphology at the tail of the molten pool, and the morphology and intensity distribution of the plasma plume on the molten pool surface. The geometric dimensions of the molten pool mainly refer to its width and length. Simultaneously, an infrared thermometer is used to measure the temperature field distribution of the molten pool and its adjacent heat-affected zone in real time. The operating band of the infrared thermometer is matched to the radiation characteristics of the molten pool, and the temperature measurement data and image data are synchronized using a unified timestamp. The actual operating parameters of the high-energy beam are recorded synchronously. These parameters include real-time laser power, scanning speed, and powder feeding rate. These parameters are read directly from the data ports of the laser and motion controller, as shown in Table 1.

[0039] Table 1: Monitoring Parameters for Melting and Solidification Characteristics

[0040] In practice, the control parameters of the improved path planning algorithm are dynamically adjusted based on the melting and solidification characteristic information, and the geometric dimensions of the extracted molten pool in real time are compared with the preset ideal molten pool dimensions for the current layer. Dimensional deviation... It can be done through the formula:

[0041] in: This is the current measured value of the molten pool width. For the target molten pool width, This is the current measured length of the molten pool. The target molten pool length. If there is a dimensional deviation... If the allowable threshold is exceeded, a power adjustment command or a speed adjustment command is generated. The allowable threshold is set according to process stability requirements, for example, a threshold of 0.15 mm. In specific implementation, when the measured value of the molten pool width is continuously greater than the target molten pool width, a command to reduce laser power or increase scanning speed is generated. The adjustment command is fed back to the improved path planning algorithm, which updates the laser power setting or scanning speed setting value at subsequent path points online accordingly.

[0042] In some embodiments, the solidification line morphology at the tail of the molten pool is analyzed to determine whether there are abnormal grain growth or defect initiation tendencies. The criteria for judgment include sudden bends in the solidification line, sharp increases in local spacing, or disappearance of the solidification line. If an abnormal tendency is found, a path replanning instruction is triggered, and the improved path planning algorithm temporarily inserts a compensation scan segment with a specific orientation into the subsequent path. Optionally, the compensation scan segment can be a short line intersecting the main scan line at a certain angle to improve local thermal cycling conditions and promote remelting and sequential solidification in that region. Based on the morphology and intensity distribution of the plasma plume on the molten pool surface, the evaporation loss of alloying elements and energy absorption stability within the molten pool are evaluated. The evaluation is performed by analyzing the standard deviation of the plume area and grayscale value fluctuations. It is understood that severe fluctuations in the plasma plume usually indicate molten pool instability. If the evaluation results show instability, a beam morphology adjustment instruction is generated. This instruction is used to dynamically adjust the defocusing amount or spot pattern of the high-energy beam, such as switching from positive defocusing to negative defocusing, or from a circular spot to a rectangular spot, to change the energy distribution. In some embodiments, the improved path planning algorithm pre-sets an adjustment rule base for different anomaly characteristics, and the rule base maps the characteristic information with the type and magnitude of the adjustment instruction.

[0043] In one embodiment of the present invention, the continuous gradient change in composition and microstructure of the water-erosion resistant functional body in the thickness direction is achieved by the following method: at the beginning of the manufacturing process, the powder feeding device is controlled to deliver corrosion-resistant alloy powder with a matrix phase content that is dominant, so as to form a bottom layer region with matching strength and toughness adjacent to the blade substrate in the water-erosion resistant functional body. As the number of cladding layers increases towards the outermost edge of the blade inlet, the powder feeding device is controlled by the improved path planning algorithm to continuously and linearly increase the proportion of carbide-forming element powder in the corrosion-resistant alloy powder, while the laser energy input is adjusted accordingly to promote the generation and uniform distribution of in-situ carbides. When approaching the outermost surface of the water-erosion resistant functional body, the proportion of carbide-forming element powder in the corrosion-resistant alloy powder reaches its maximum. At the same time, the improved path planning algorithm controls the high-energy beam to adopt a high-power-density, fast-scanning strategy to obtain a surface microstructure with fine interdendritic carbides and high hardness. From the bottom layer to the surface layer, the chemical composition, carbide content and type, and grain size of the water erosion resistant functional body all exhibit a continuous gradient transition, with no macroscopic interface.

[0044] After the cladding manufacturing of the water-erosion-resistant functional body is completed, it undergoes in-situ heat treatment. While the cladding manufacturing of the water-erosion-resistant functional body is complete but the temperature has not yet dropped to room temperature, the ambient temperature inside the forming chamber is controlled to rise to a preset solution treatment temperature range and held for a period of time. After the holding period, the chamber temperature is controlled to cool to the aging treatment temperature range at a programmed rate and held again. After the aging treatment, the entire blade, along with the water-erosion-resistant functional body, is controlled to cool to room temperature at a rate not exceeding the critical cooling rate. The temperature change curve during the in-situ heat treatment process is designed with zoned optimization based on the gradient composition of the water-erosion-resistant functional body to achieve synchronous optimization of the performance of each zone of the gradient material.

[0045] In specific implementation, the gradient structure of the water erosion resistant functional body and subsequent heat treatment are achieved. The water erosion resistant functional body exhibits a continuous gradient change in composition and microstructure along the thickness direction of the three-dimensional protective structure model. In specific implementation, this continuous gradient change in composition and microstructure is achieved through precise control of powder feeding and the manufacturing process. At the beginning of the manufacturing process, the powder feeding device is controlled to deliver corrosion-resistant alloy powder with a dominant matrix phase content. Specifically, in the initial powder feeding mixture, by mass fraction, cobalt-based alloy base powder accounts for 90%, tungsten carbide powder accounts for 8%, and rare earth yttrium powder accounts for 2%, forming a bottom layer region with matched strength and toughness adjacent to the blade substrate in the water erosion resistant functional body. As the number of cladding layers increases towards the outermost edge of the blade inlet, the powder feeding device is controlled through an improved path planning algorithm to continuously and linearly increase the proportion of carbide-forming element powder in the corrosion-resistant alloy powder, linearly increasing from 8% in the bottom layer to 25% in the surface layer. In some embodiments, the powder feeding ratio... With cladding height The relationship is given by the formula:

[0046] in: The proportion of tungsten carbide in the bottom layer. The proportion of tungsten carbide in the surface layer. The total height of the water erosion resistant functional body, The gradient control index is used. While increasing the powder feeding ratio, the improved path planning algorithm adjusts the laser energy input accordingly, gradually increasing the laser power from 900 watts at the bottom layer to 1300 watts at the surface layer, and adjusting the scanning speed from 8 mm / s to 5 mm / s to promote the formation and uniform distribution of in-situ carbides.

[0047] In practical implementation, when the gradient manufacturing process approaches the outermost surface of the water-erosion resistant functional body, the proportion of carbide-forming element powder in the corrosion-resistant alloy powder reaches its highest level, with tungsten carbide powder reaching 25%. Simultaneously, an improved path planning algorithm controls the high-energy beam using a high-power-density, fast-scanning strategy. High power density is achieved through focusing a small spot size and high power, for example, using a 1300-watt laser power and a 0.8 mm spot diameter, while maintaining a rapid scanning speed of 5 mm per second, to obtain a fine, high-hardness surface microstructure reinforced with interdendritic carbides. From the bottom layer to the surface, the chemical composition of the water-erosion resistant functional body exhibits a continuous gradient transition, with tungsten carbide content gradually changing from 8% to 25%, and carbide content and type changing from sparse primary carbides to dense interdendritic eutectic carbides. Grain size transitions from relatively coarse equiaxed crystals to fine columnar dendrites. There are no macroscopic interfaces between the regions (see Table 2).

[0048] Table 2: Process Parameters for Gradient Structure of Water Erosion-Resistant Functional Body

[0049] After the cladding of the water-erosion resistant functional body is completed, in-situ heat treatment is performed on the cladding. While the cladding is complete but the temperature has not yet dropped to room temperature, the ambient temperature inside the forming chamber is controlled to rise to a preset solution treatment temperature range. In some embodiments, the preset solution treatment temperature range is 1150°C to 1200°C for cobalt-based alloy systems. The forming chamber is heated to 1180°C at a rate of 10°C per minute and held for two hours. After the holding period, the chamber temperature is controlled to cool to the aging treatment temperature range at a programmed rate, which can be 5°C per minute. The aging treatment temperature range is 750°C to 800°C for cobalt-based alloy systems, and the chamber is held again at 760°C for four hours. After the aging treatment, the entire blade, along with the water-erosion resistant functional body, is controlled to cool to room temperature at a rate not exceeding the critical cooling rate. The critical cooling rate can be set to 3°C per minute to avoid excessive thermal stress. Optionally, the temperature change curve during in-situ heat treatment is optimized by partitioning based on the gradient composition of the water-erosion resistant functional body. For the surface area with high carbide content, the holding time can be extended during the aging treatment stage to achieve synchronous optimization of the performance of each zone of the gradient material. It can be understood that in-situ heat treatment is carried out directly in a forming chamber with an inert protective atmosphere, avoiding the oxidation risk caused by workpiece transfer and the energy consumption of reheating.

[0050] In one embodiment of the present invention, the water erosion resistance performance of the preset three-dimensional protective structure model is simulated and optimized before cladding manufacturing. Based on computational fluid dynamics, the impact process of water droplets on the inlet edge of the blades under turbine operating conditions is simulated, and the impact velocity, frequency, and angle distribution of water droplets at different locations are obtained as water droplet impact parameters. Based on these water droplet impact parameters, solid mechanics simulation methods are used to calculate the stress distribution, strain energy density, and potential material loss rate of the three-dimensional protective structure model under different thicknesses and surface configurations. With minimizing material loss rate and maximizing impact fatigue life as optimization objectives, and manufacturability as a constraint, the thickness distribution, surface curvature, and transition contour with the substrate of the three-dimensional protective structure model are iteratively optimized. The optimized model geometric data is output as the final preset three-dimensional protective structure model used to control cladding manufacturing.

[0051] Quality prediction and traceability of the water-erosion-resistant functional body are performed based on cladding manufacturing process data. Control parameters of the improved path planning algorithm for each layer during the cladding manufacturing process, real-time collected fusion characteristic information, and dynamically adjusted records are recorded. These records are correlated with the target performance parameters of the corresponding cladding area obtained through water-erosion performance simulation optimization, establishing a correlation database between manufacturing process parameters and local performance. After manufacturing is completed, data is extracted from the correlation database. First, the predicted performance of the water-erosion-resistant functional body at its corresponding spatial location is determined. The predicted performance includes predicted hardness, predicted toughness, and predicted residual stress. Then, a predicted performance distribution map for the corresponding spatial location is generated based on the predicted performance. Each manufactured blade and its water-erosion-resistant functional body is assigned a unique identifier, and the predicted performance distribution map, key manufacturing process parameters, and simulation optimization model version information are bound and stored under this unique identifier.

[0052] In practical implementation, pre-cladding model simulation optimization and post-manufacturing quality traceability are crucial. Before cladding, the water erosion resistance of the pre-designed three-dimensional protective structure model is simulated and optimized. Based on computational fluid dynamics, the impact process of water droplets on the inlet edge of the blades under turbine operating conditions is simulated. The simulated operating conditions are set as the operating parameters of the last-stage long blades of the turbine under typical wet steam conditions. The impact velocity, frequency, and angle distribution of water droplets at different positions on the inlet edge surface of the blades are obtained; these parameters serve as the water droplet impact parameters for subsequent mechanical analysis. Based on the water droplet impact parameters, solid mechanics simulation methods are used to calculate the stress distribution, strain energy density, and potential material loss rate of the three-dimensional protective structure model under different thicknesses and surface configurations. In the solid mechanics simulation, the material is given elastoplastic properties corresponding to the design gradient.

[0053] In practical implementation, the simulation optimization process aims to minimize material loss rate and maximize impact fatigue life, with manufacturability as a constraint. Manufacturability constraints include minimum cladding thickness and maximum overhang angle. The thickness distribution, surface curvature, and transition profile with the substrate of the three-dimensional protective structure model are iteratively optimized. In some embodiments, the optimization process is driven by a parametric model, modifying the thickness parameters in each iteration. and radius of curvature And through a comprehensive evaluation index To guide the direction of optimization:

[0054] in: This is the calculated value for material loss rate. This is the calculated value for impact fatigue life. and These are the weighting coefficients. This can be understood as the optimization algorithm continuously adjusting within the constraints. and Seeking to make comprehensive evaluation indicators Minimized model configuration. The optimized model geometry data is output and stored in STL format as the final preset 3D protective structure model used to control cladding manufacturing.

[0055] This method uses cladding manufacturing process data to predict and trace the quality of water-erosion resistant functional bodies. It records the control parameters of the improved path planning algorithm for each layer during the cladding manufacturing process, real-time acquired melting and solidification characteristic information, and dynamic adjustment records. In specific implementations, the recorded control parameters of the improved path planning algorithm include the scanning speed, laser power, and path spacing for each layer; the recorded melting and solidification characteristic information includes the average molten pool width and molten pool tail morphology rating; and the recorded dynamic adjustment records include power adjustment commands and their magnitudes. These records are then mapped to the target performance parameters of the corresponding cladding area obtained through water-erosion resistance performance simulation optimization. These target performance parameters include the required microhardness, fracture toughness, and residual compressive stress values ​​for that location. In some embodiments, a database linking manufacturing process parameters and local performance is established using a machine learning model. The manufacturing process parameters are used as input features, and the target performance parameters obtained through simulation optimization are used as part of the training labels.

[0056] After manufacturing is completed, data is extracted from the associated database to determine the predicted performance of the corresponding spatial location of the water erosion-resistant functional component. The predicted performance includes predicted hardness, predicted toughness, and predicted residual stress. These predictions are obtained by inputting the actual manufacturing process parameters for that location into a trained associated model. Then, a predicted performance distribution map is generated based on the predicted performance, visually presenting the predicted performance values ​​of different regions of the water erosion-resistant functional component in the form of two-dimensional contour lines or three-dimensional cloud maps. Each manufactured blade and its water erosion-resistant functional component is assigned a unique identifier, which can be a QR code or an RFID tag. Optionally, the predicted performance distribution map, key manufacturing process parameters, and simulation optimization model version information are bound and stored under the unique identifier in the factory's manufacturing execution system database. It can be understood that by scanning the unique identifier, the entire chain of data for the blade's water erosion-resistant functional component—from design to simulation to manufacturing to prediction—can be traced.

[0057] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for manufacturing anti-water erosion sheets for long turbine blades, characterized in that, include: Prepare corrosion-resistant alloy powder suitable for laser melting deposition process; On the surface of the area to be protected on the turbine blade substrate, based on a preset three-dimensional protective structure model, an improved path planning algorithm is used to control a high-energy beam to perform layer-by-layer scanning and cladding of the corrosion-resistant alloy powder. During the cladding process, the solidification characteristics of the molten pool are collected in real time; Based on the fusion characteristic information, the control parameters of the improved path planning algorithm are dynamically adjusted to manufacture in situ a water erosion resistant functional body that is metallurgically bonded to the blade substrate. The improved path planning algorithm plans multiple cladding path combinations with different scanning strategies based on the water erosion resistance requirements at different locations in the three-dimensional protective structure model, and performs path rotation between layers. The water erosion resistant functional body has a continuous gradient change in composition and microstructure in the thickness direction of the three-dimensional protective structure model.

2. The method for manufacturing anti-water erosion sheets for long turbine blades according to claim 1, characterized in that, The preparation of corrosion-resistant alloy powder suitable for laser melting deposition process includes: Select at least one of cobalt-based alloys, nickel-based alloys, or iron-based alloys as the base powder; Carbide-forming element powder and rare earth element powder are added to the base powder. The carbide-forming element powder includes tungsten carbide, chromium carbide or vanadium carbide, and the rare earth element powder includes yttrium or cerium. A mixed powder comprising base powder, carbide-forming element powder and rare earth element powder is subjected to mechanical alloying treatment. The mechanical alloying treatment is carried out under an inert atmosphere, and the ball milling time is sufficient to allow the carbide-forming element powder and the rare earth element powder to be uniformly embedded in the surface and near-surface layer of the base powder particles. The powder that has undergone mechanical alloying is sieved and dried to obtain the corrosion-resistant alloy powder. The particle size distribution of the corrosion-resistant alloy powder is controlled within a certain range, and the sphericity of the powder meets the preset flowability requirements.

3. The method for manufacturing anti-water erosion sheets for long turbine blades according to claim 2, characterized in that, The process involves, based on a pre-defined three-dimensional protective structure model, using an improved path planning algorithm to control a high-energy beam to perform layer-by-layer scanning and cladding of the corrosion-resistant alloy powder on the surface of the area to be protected on the turbine blade substrate, including: The surface of the area to be protected of the blade substrate is pretreated, and the pretreatment includes cleaning, drying and preheating; The blade substrate is fixed in a forming chamber with multi-axis linkage function, and the transformation relationship between the blade substrate coordinate system and the equipment motion coordinate system is established. Based on the three-dimensional protective structure model, the initial forming layer parameters of the water erosion resistant functional body are set in the improved path planning algorithm. The initial forming layer parameters include the set first laser power and first scanning speed, so as to form a thin-layer bonding area with controlled dilution rate on the surface of the blade substrate. Above the initial forming layer that forms the thin-layer bonding area, the improved path planning algorithm generates cladding paths layer by layer according to the geometric features and performance requirements of different sections of the three-dimensional protective structure model. The high-energy beam melts the corrosion-resistant alloy powder synchronously delivered to the cladding area according to the generated cladding path, and the molten material is deposited and solidified layer by layer.

4. The method for manufacturing anti-water erosion sheets for long turbine blades according to claim 1, characterized in that, The working principle of the improved path planning algorithm includes: Input the digital file of the three-dimensional protective structure model, perform layered slicing on the model, and obtain a series of two-dimensional cross-sectional contours; For each two-dimensional cross-sectional profile, the algorithm assigns a performance level index based on the thickness position of the current two-dimensional cross-sectional profile in the overall model. The performance level index is related to the required hardness and toughness ratio at the corresponding position. Based on the performance level index, the corresponding basic scanning strategy is called from the preset path strategy library. The basic scanning strategy defines a combination of core parameters, including scan line spacing, scan line direction, scan speed, laser power, and beam shape. When applying the basic scanning strategy, the algorithm introduces a path perturbation factor, which is dynamically calculated based on the deviation between the actual morphology and the ideal morphology of the current deposition layer. This factor is used to fine-tune the cladding path of the current layer to compensate for the forming error. After completing the path planning for the current layer, the algorithm applies an interlayer path rotation angle to the path planning for the next deposition layer. The interlayer path rotation angle is optimized based on the simulation results of the residual stress distribution of the current layer in order to reduce the overall forming stress.

5. The method for manufacturing anti-water erosion sheets for long turbine blades according to claim 1, characterized in that, The process of collecting solidification characteristic information of the molten pool in real time during cladding includes: A coaxial vision monitoring system was used to acquire dynamic images of the molten pool area; The dynamic image is processed to extract the solidification feature information, which includes the geometric dimensions of the molten pool, the solidification line morphology at the tail of the molten pool, and the morphology and intensity distribution of the plasma plume on the surface of the molten pool. Infrared thermometers were used to measure the temperature field distribution of the molten pool and its adjacent heat-affected zone in real time. The actual operating parameters of the high-energy beam are recorded synchronously, including real-time laser power, scanning speed, and powder feeding rate.

6. The method for manufacturing anti-water erosion sheets for long turbine blades according to claim 5, characterized in that, Based on the melting and solidification characteristic information, the control parameters of the improved path planning algorithm are dynamically adjusted, including: The geometric dimensions of the molten pool extracted in real time are compared with the ideal molten pool dimensions preset for the current layer. If the size deviation exceeds the allowable threshold, a power adjustment command or a speed adjustment command is generated and fed back to the improved path planning algorithm. The improved path planning algorithm updates the laser power setting value or scanning speed setting value at subsequent path points online accordingly. Analyze the solidification line morphology at the tail of the molten pool to determine whether there is abnormal grain growth or defect initiation tendency. If there is an abnormal tendency, trigger the path replanning instruction. The improved path planning algorithm temporarily inserts a compensation scan line segment with a specific direction in the subsequent path to improve the local thermal cycling conditions. Based on the morphology and intensity distribution of the plasma plume on the surface of the molten pool, the evaporation loss of alloying elements and the stability of energy absorption inside the molten pool are evaluated. If the evaluation results show instability, a beam morphology adjustment command is generated to dynamically adjust the defocusing amount or spot pattern of the high-energy beam.

7. The method for manufacturing anti-water erosion sheets for long turbine blades according to claim 1, characterized in that, The water erosion resistant functional body has a continuous gradient change in composition and microstructure in the thickness direction of the three-dimensional protective structure model, which is achieved through the following methods: At the beginning of the manufacturing process, the powder feeding device is controlled to deliver corrosion-resistant alloy powder with a matrix phase content that is dominant, so as to form a bottom layer region with matching strength and toughness adjacent to the blade substrate in the water erosion resistant functional body. As the number of cladding layers increases toward the outermost edge of the blade inlet, the improved path planning algorithm controls the powder feeding device to continuously and linearly increase the proportion of carbide-forming element powder in the corrosion-resistant alloy powder, while adjusting the laser energy input accordingly to promote the generation and uniform distribution of in-situ carbides. When approaching the outermost surface of the water-erosion resistant functional body, the proportion of carbide-forming element powder in the corrosion-resistant alloy powder reaches its highest level. At the same time, the improved path planning algorithm controls the high-energy beam to adopt a high-power-density and fast-scanning strategy to obtain a fine interdendritic carbide-reinforced, high-hardness surface microstructure. From the bottom layer to the surface layer, the chemical composition, carbide content and type, and grain size of the water erosion resistant functional body all exhibit a continuous gradient transition, with no macroscopic interface.

8. The method for manufacturing anti-water erosion sheets for long turbine blades according to claim 7, characterized in that, The method further includes performing in-situ heat treatment on the anti-water erosion functional body after completing the cladding manufacturing, specifically: When the water erosion cladding of the anti-erosion functional body is completed and the temperature has not yet dropped to room temperature, the ambient temperature inside the forming chamber is controlled to rise to the preset solution treatment temperature range and kept at that temperature for a period of time. After the insulation is completed, the temperature of the control chamber is cooled to the aging treatment temperature range at a programmed rate, and then the insulation is carried out again. After the aging treatment is completed, the entire blade, together with the water erosion resistant functional body, is controlled to be cooled to room temperature at a rate not exceeding the critical cooling rate. The temperature change curve during the in-situ heat treatment process is optimized by partitioning based on the gradient composition of the water erosion resistant functional body, so as to achieve synchronous optimization of the performance of each region of the gradient material.

9. The method for manufacturing anti-water erosion sheets for long turbine blades according to claim 1, characterized in that, The method further includes performing water erosion resistance simulation optimization on the preset three-dimensional protective structure model before cladding manufacturing, specifically: Based on computational fluid dynamics, the impact process of water droplets on the inlet edge of the blades under the operating conditions of a steam turbine was simulated, and the impact velocity, impact frequency and impact angle distribution of water droplets at different positions were obtained as water droplet impact parameters. Based on the water droplet impact parameters, solid mechanics simulation methods are used to calculate the stress distribution, strain energy density, and potential material loss rate of the three-dimensional protective structure model under different thicknesses and different surface configurations. With the optimization objectives of minimizing material loss rate and maximizing impact fatigue life, and with manufacturability as a constraint, the thickness distribution, surface curvature, and transition profile with the substrate of the three-dimensional protective structure model are iteratively optimized. The optimized model geometry data is output as the final preset three-dimensional protective structure model used to control the cladding manufacturing process.

10. A method for manufacturing anti-water erosion sheets for long turbine blades according to claim 9, characterized in that, The method further includes quality prediction and traceability of the water erosion resistant functional body based on cladding manufacturing process data, specifically: The control parameters of the improved path planning algorithm for each layer during the cladding process are recorded, along with the real-time collected fusion characteristic information and dynamically adjusted records. The records are associated with the target performance parameters of the corresponding cladding area obtained through water erosion resistance simulation optimization, and a database of the relationship between manufacturing process parameters and local performance is established. After manufacturing is completed, data is extracted from the associated database to first determine the predicted performance of the water erosion resistant functional body at the corresponding spatial location. The predicted performance includes predicted hardness, predicted toughness, and predicted residual stress. Then, a predicted performance distribution map of the corresponding spatial location is generated based on the predicted performance. Each manufactured blade and its water erosion-resistant functional component are assigned a unique identifier, and the predicted performance distribution map, key manufacturing process parameters, and simulation optimization model version information are bound and stored under the unique identifier.

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