A wide beam spot high throughput additive manufacturing and cladding apparatus and method of operation thereof

Abstract

The present application relates to a kind of wide beam spot high-flux additive manufacturing and cladding device and its working method, belong to material surface engineering field, external fiber access fiber interface input laser, laser sequentially passes through collimating lens, DOE diffractive optical element, converging lens and protective lens, the laser beam of wide beam spot is output at nozzle outlet, spot width is 20-40mm.Two powder feeding tanks are connected on the nozzle powder feeding interface by powder feeding pipe, cooling water pipe is connected on multiple water cooling interfaces to form circulation, and external protective gas is connected on the protective gas interface to provide central protective gas.The present application can efficiently carry out additive manufacturing and cladding to large workpiece with laser beam of spot width 20-40mm, obtain metallurgical bonding single-layer or multi-layer additive manufacturing and cladding layer, and also can obtain high-flux sample array with different components by continuous and accurate control of composition, provide suitable composition and efficient protection technology for large workpiece working in extreme environment.

Description

Technical Field

[0001] This invention relates to a wide-beam high-throughput additive manufacturing and cladding apparatus and its working method, belonging to the field of materials surface engineering technology. Background Technology

[0002] As resource development continues to advance into the deep sea, deep earth, and deep space, higher demands are placed on the safety of large-scale engineering equipment operating in extreme environments and the service life of key components. Developing efficient protection technologies for workpiece surfaces and, at the same time, developing suitable protective materials as quickly as possible are effective ways to improve the performance of large-scale engineering equipment.

[0003] Numerous technical reports and engineering applications have been published. Patent publication number CN111926324A discloses an integrated wide-spot deep-hole laser cladding head. This head features an innovative upper and lower air knife structure, effectively protecting the laser cladding head and improving cladding efficiency. An innovative camera function allows for real-time observation of the molten pool, powder spreading status, and cladding surface quality, enabling operators to detect cladding quality issues immediately. Patent publication number CN111254432A discloses a fully water-cooled high-power wide-band cladding head for internal holes. Its laser reflector module reflects parallel light passing through the light-transmitting tube assembly at right angles, transforming a circular spot into a wide spot. The powder feeding nozzle assembly splits metal powder into multiple paths, converging them with the wide spot to a single point. This effectively solves the problems of traditional laser heads failing to meet the requirements of internal hole repair and having low processing efficiency. Patent publication number CN111577928A discloses a high-wear-resistant ball valve and its manufacturing method based on high-speed laser cladding technology. This method utilizes high-speed laser cladding technology to first create a transition layer on the ball valve surface, then precisely clad a layer of specific high-hardness alloy powder onto this transition layer, followed by wide-spot laser scanning and remelting. This improves surface quality and solves the problems of preheating and cracking associated with traditional laser cladding methods for creating high-wear-resistant alloy layers. Patent publication number CN111593340A discloses a laser cladding method for the inner wall of a hydraulic support cylinder. This method uses a wide-spot, off-axis, broadband powder-feeding laser cladding device to perform laser cladding and form a cladding layer. It combines the advantages of wide-spot laser cladding technology and angled coaxial laser cladding technology, reducing the production cost of cladding the inner wall of the hydraulic support cylinder. Patent publication number CN111088491A discloses a rectangular laser cladding powder feeding nozzle with adjustable powder feeding width. This rectangular nozzle allows for convenient adjustment of the powder output width as needed without redesigning or reprocessing the nozzle, solving the problem of fixed and inconvenient replacement of traditional wide-spot laser cladding powder feeding nozzles. Patent publication number CN110923705A discloses a multifunctional powder feeding system, including a laser, a powder feeder, an adjustment mechanism, a wide-spot powder feeding channel, a protective gas blowing channel, and a powder feeding water-cooling channel. The wide-spot powder feeding port is centrally located, with the protective gas blowing channel and the powder feeding port water-cooling channel fixed above and below it respectively. This compact structure reduces size and facilitates operation. Patent publication number CN110453217A discloses a wide-spot deep-hole laser cladding head, solving the bottleneck problem in the development of existing deep-hole laser cladding technology. It can operate continuously and stably, is highly integrated, and has a small size, showing broad application prospects.Patent publication number CN109317857A discloses a flat continuous welding wire, its application, and preparation method. It proposes a flat continuous welding wire suitable for rectangular energy spot welding, along with its application and preparation method. The continuous welding wire has a rounded rectangular or flattened round rectangular cross-section, with a width ranging from 3mm to 30mm and a cross-sectional thickness ranging from 0.3mm to 1.0mm. The wire type is solid or powder-cored. It is used for welding rectangular energy spots, such as wide-spot laser welding and wide-spot electron beam welding. Through specific size design, it is well-suited for welding rectangular energy spots, solving the problem that existing welding wires cannot be used for continuous welding of rectangular energy spots, thus expanding the application fields of welding wires. Patent publication number CN104611515A discloses an adjustable wide-spot reflective focusing laser internal hole quenching head, which improves the hardness, wear resistance, and corrosion resistance of the inner wall of parts, saves on part usage costs, extends service life, and ensures long-term effective internal hole quenching processing.

[0004] Meanwhile, in the field of high-throughput technology, patent publication number CN114713845A discloses a method for laser rapid prototyping of high-throughput metal samples, belonging to the field of high-energy beam rapid prototyping material preparation technology. The method provides a fully automated control of multi-channel powder feeding cylinders through equipment upgrades and software updates. The process parameters and / or material composition of the high-throughput material design are written as variables into the path program of a single sample. The position of each sample is determined by writing code, and the path program of each sample is run sequentially using the code. This allows for fully automated control of the laser rapid prototyping process by running a single program file, meeting the requirements for high-throughput material preparation of large batches of samples in one go, and enabling rapid screening of alloy composition ratios and rapid optimization of material preparation process parameters. Patent publication number CN109971929A discloses a high-throughput material preparation and performance characterization system. Compared with existing technologies, the high-throughput material preparation and performance characterization system provided in this application can simultaneously overcome the drawbacks of unstable workpiece transfer speed and uncontrollable workpiece temperature after heating, improving the accuracy of the experiment. Patent publication number CN109207995A discloses a high-throughput plasma cladding preparation system and its implementation method for wear-resistant materials. The system includes multiple material cylinders arranged from top to bottom, a first powder feeding mechanism, at least one stirring tank, a powder storage tank, a second powder feeding mechanism, and a plasma generator. Each material cylinder corresponds to a first powder feeding mechanism. In practice, the required powder is placed into each material cylinder. By adjusting the speed of the servo motor of each material cylinder's powder feeding mechanism, the powder in each cylinder falls into the stirring tank below according to a designed ratio. After being stirred and mixed, the powder is sent to the powder storage tank to await plasma cladding. This invention can directly prepare multiple formulations and different processes of wear-resistant coatings or gradient materials on the same metal substrate in one step, reducing experimental errors. Patent publication number CN108330456A discloses a high-throughput material preparation device and its application. It prepares a series of new materials by magnetron sputtering deposition at different ratios and can achieve continuous high-throughput production, greatly facilitating the research and development of new materials and the construction of material genome libraries. Patent publication number CN105891243A discloses a two-dimensional continuous composition sample, its preparation method, and its application in high-throughput rapid determination of phase diagrams. The two-dimensional continuous composition sample is an equilateral triangular thin sheet, the composition distribution of which is consistent with the composition distribution of the ternary phase diagram represented by the equilateral triangle. This two-dimensional continuous composition sample can be prepared by three methods: solid-state reaction, 3D printing, and slurry or suspension mixing. It can be annealed or quenched at appropriate temperatures to meet the requirements of phase diagram determination and material screening applications. This invention can significantly increase the number of different composition samples synthesized in a single batch, providing greater sample throughput support for high-throughput material screening and rapid determination of ternary phase diagrams.

[0005] The inventions mentioned above have improved the efficiency of additive manufacturing and cladding, as well as the efficiency of material composition and process optimization to varying degrees. However, there are no reports on devices and technologies that integrate wide-beam laser additive manufacturing and cladding, high-throughput optimization, and precise control of composition. This poses a serious constraint on the efficient protection of large components working in extreme environments and the matching design of material composition. Summary of the Invention

[0006] For large components operating in environments subject to ablation, abrasion, high temperature, and low temperature, efficient protection and targeted design of protective materials are required. This invention proposes a wide-beam-spot high-throughput additive manufacturing and cladding device and its operating method. Specifically, the system features wide-beam-spot laser additive manufacturing and cladding, high-throughput optimization, and precise composition control. It can efficiently perform additive manufacturing and cladding on large workpieces using a laser beam with a spot width of 20-40mm, obtaining single-layer or multi-layer additive manufacturing and cladding layers with metallurgical bonding. Furthermore, by continuously and precisely controlling the composition, it can obtain high-throughput sample arrays with different compositions. By comparing the relationship between composition and performance, rapid composition optimization and screening are achieved. This provides suitable compositions and highly efficient protection technology for large components operating in extreme environments.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] On the one hand, the present invention provides a wide-beam high-throughput additive manufacturing and cladding apparatus, including a wide-beam cladding head, a high-throughput powder feeding system and a mechanical motion system. The wide-beam cladding head is fixed to the mechanical motion system by a flange mounting plate. The high-throughput powder feeding system is used to adjust the quality of the powder delivered and includes a powder feeding tank A and a material feeding tank B.

[0009] The wide-beam spot cladding head includes a laser shaping structure and a gas-powder mixing path structure for synchronous powder feeding. The laser shaping structure includes a collimating lens, a DOE diffractive optical element, a focusing lens, and a protective lens. The gas-powder mixing path structure for synchronous powder feeding includes an optical fiber interface, a water-cooling interface, a central protective gas, a focus adjustment sleeve, and a nozzle. Powder feeding tanks A and B are connected to the powder feeding interface of the nozzle through powder feeding pipes. The cooling water pipes of an external chiller are connected to multiple water-cooling interfaces to form a cooling water circulation. An external protective gas is connected to the protective gas interface of the wide-beam spot cladding head to provide central protective gas. An external optical fiber is connected to the optical fiber interface to input laser light. The laser light passes sequentially through the collimating lens, the DOE diffractive optical element, the focusing lens, and the protective lens, and outputs a wide-beam spot at the nozzle outlet.

[0010] Preferably, powder feeding grooves are provided on both sides of the nozzle, and powder is sprayed out through the powder feeding grooves. The outlet of the powder feeding groove is a rectangular powder feeding outlet, and the rectangular powder feeding outlet is divided into 7 or more small rectangular holes with a spot width of 20-40mm.

[0011] To match the width of the delivered powder with the width of the laser beam, the conventional circular powder outlet was widened to a rectangular one. Furthermore, to ensure uniform powder output from the entire rectangular outlet, the rectangular opening was divided into multiple smaller rectangular openings, preferably seven. To guarantee that more powder entering from the center was distributed, the left and right sides of the rectangular opening were widened. This allows powder entering from the upper center to be evenly delivered through the seven smaller rectangular openings. The powder, ejected from these smaller rectangular openings and fed into the laser beam, is fully melted before reaching the workpiece, improving powder fusion properties, reducing rebound on the workpiece surface, and increasing powder utilization to 95%. This results in excellent additive manufacturing and cladding quality, making it particularly suitable for high-throughput additive manufacturing and cladding processes requiring precise control of the cladding zone composition.

[0012] The improvements of this invention are twofold: first, the large rectangular hole is divided into seven smaller rectangular holes; second, the upper left and right sides of the rectangular holes are widened, allowing the powder to be evenly delivered from the seven smaller rectangular holes, and smoothly and evenly additively manufactured or clad onto the workpiece under the action of the wide beam spot.

[0013] Preferably, the high-throughput powder feeding system further includes a powder feeding motor and a powder feeding turntable. The powder feeding motor is installed inside the cabinet of the high-throughput powder feeding system. The output shaft of the powder feeding motor is connected to the powder feeding turntable. The rotation speed of the powder feeding motor determines the rotation speed of the powder feeding turntable, which is used to control the powder quality falling into the powder feeding turntable per unit time.

[0014] Preferably, the pressure of the powder delivery gas is regulated by a gas pressure reducing valve on an external gas supply device (e.g., a gas cylinder), and the gas flow rate is regulated by a gas flow meter on the cabinet of the high-throughput powder delivery system.

[0015] This invention relates to a high-throughput powder feeding system designed to establish the relationship between the composition of multi-component cladding materials and target properties. This results in a continuously varying sample array with precisely controlled composition, corresponding to different properties, enabling the rapid delivery of suitable components for various operating conditions. Precise composition control is achieved through a powder feeding motor driving a powder feeding turntable, combined with a negative pressure powder feeding system using a powder feeding gas. The rotational speed of the powder feeding turntable determines the amount of powder supplied per unit time, while the pressure and flow rate of the powder feeding gas determine the amount of powder carried away per unit time. This combination allows for precise and continuous control of one or more components. When gas-powder mixtures corresponding to different compositions reach the nozzle outlet via their respective powder pipelines and channels, they are fed into the rectangular powder feeding outlet end of the nozzle. After being ejected through multiple small rectangular holes on both sides of the rectangular nozzle, they are simultaneously fed into the laser beam, where they are fully fused and melted before reaching the working area. Combined with the parameter settings of the mechanical motion system of this invention, high-throughput additive manufacturing and cladding can produce sample arrays representing different compositions and properties.

[0016] Preferably, the powder to be additively manufactured and clad is preloaded into powder feeding tanks. There are at least two powder feeding tanks, providing powders of two different components. Powder feeding tank A contains a single component or a mixture of components A, and powder feeding tank B contains another single component or a mixture of components B. The powder from powder feeding tank A and powder feeding tank B correspond to two rows of powder feeding grooves (7 small rectangular holes) on both sides of the wide beam nozzle, and reach the nozzle outlet through their respective powder pipelines and powder channels.

[0017] On the other hand, the present invention provides a method for operating the above-mentioned wide-beam high-throughput additive manufacturing and cladding apparatus. When laser light is input through the external fiber optic interface, the divergent beam transmitted from the external fiber enters through the fiber optic interface and becomes parallel light. Then, it passes through a DOE diffraction optical element, specifically a beam-uniforming element that is insensitive to the incident spot size and beam quality. The beam is precisely shaped from a circular spot into a rectangular spot. Finally, it passes through a focusing lens and a protective lens, and the beam is focused towards the nozzle exit, where a rectangular wide-beam spot is obtained. At this time, the focus adjustment sleeve is adjusted to make the laser... The laser focal point (although called the focal point, it is actually a solid rectangular spot, at which point the spot size is the smallest and the energy density is the highest) is matched with the powder convergence points on both sides. Since the powder on both sides is ejected from two rows of small rectangular holes, it is actually two converging lines, so that the laser focal point is located 2mm above and below the powder convergence point. After being ejected, the powder is simultaneously sent into the wide laser beam. It begins to be heated and melted the moment it enters the wide beam. Then, some of the melted powder mixes with each other. The powder has been fully fused and melted before reaching the workpiece, and together with the surface-melted metal workpiece, it forms a molten pool and a cladding layer.

[0018] Preferably, when the pressure and flow rate of the powder-feeding gas are constant, adjusting the speed of the powder-feeding motor can precisely control the quality of the powder being fed out; similarly, if the pressure of the powder-feeding gas and the speed of the powder-feeding motor are fixed, adjusting the flow rate of the powder-feeding gas can also precisely control the quality of the powder being fed out.

[0019] This invention utilizes gas-driven powder feeding, rather than gravity-driven feeding, based on the principle of negative pressure. The gas flow regulating valve includes a gas pressure reducing valve and a gas flow meter. Gas at a certain pressure is introduced from the inlet of the sealed powder feeding tank and ejected from the outlet. Where the flow velocity is high, the pressure is low, creating a negative pressure along the path of the airflow. This negative pressure draws in the powder from the powder trough of the powder feeding disc and transports it to the workpiece surface along with the airflow. The rotational speed of the powder feeding disc determines the amount of powder supplied per unit time, while the gas pressure and flow rate determine the amount of powder delivered per unit time.

[0020] This invention precisely controls the powder quality delivered from the two powder tanks by adjusting the speed of the powder feeding motor and the pressure and flow rate of the powder feeding air in the powder feeding system.

[0021] Preferably, during operation, the powder quality from powder feeder A remains constant, meaning the powder ratio fed into the molten pool remains unchanged, and the powder is ejected from a small rectangular hole in the powder feed trough on one side of the nozzle. The powder quality from powder feeder B changes continuously or abruptly, meaning the powder ratio fed into the molten pool is changed, and the powder is ejected from a small rectangular hole in the powder feed trough on the other side of the nozzle. The change in the powder quality from powder feeder B is coordinated with the workpiece. The powder ejected from both sides converges in a wide beam spot, forming a 20-40mm additive manufacturing or cladding band after additive cladding. The composition of this band changes continuously or stepwise, and is not fixed, achieving high-throughput powder feeding. Sample units with different compositions are processed on the wide beam cladding band, forming a high-throughput sample array for wear, erosion, and ablation tests and comparisons. This provides a powerful tool for analyzing the relationship between material composition, microstructure, and properties, quickly screening for compositional windows, and greatly improving the efficiency of material composition and property optimization.

[0022] For any aspects not covered in this invention, please refer to existing technologies.

[0023] The beneficial effects of this invention are as follows:

[0024] 1. This invention addresses the need for efficient protection and targeted design of protective materials for large components operating in ablation, abrasion, high temperature, and low temperature environments. It proposes a wide-beam high-throughput high-energy-beam additive manufacturing and cladding device and its working method. Specifically, the system has functions such as wide-beam laser additive manufacturing and cladding, high-throughput optimization, and precise control of composition.

[0025] 2. This invention can precisely shape the incident beam into a rectangular spot, which is then focused towards the cladding nozzle outlet after passing through a focusing lens and a protective lens. By adjusting the focus, the laser focus is made to converge with the powder on both sides of the nozzle, thus obtaining a laser beam with a spot width of 20-40mm, enabling high-efficiency additive manufacturing and cladding.

[0026] 3. This invention obtains a rectangular wide beam spot at the nozzle exit. To match the width of the delivered powder with the width of the wide beam spot, a rectangular powder delivery outlet is designed at the nozzle exit. Furthermore, to ensure uniform powder delivery across the entire rectangular outlet, the overall rectangular opening is divided into seven smaller rectangular openings. The powder is ejected through these seven smaller rectangular openings and fed into the laser wide beam spot, ensuring it is fully melted before reaching the workpiece. This improves the powder's fusion properties, reduces the rebound rate on the workpiece surface, and increases the powder utilization rate to 95%. Figure 4 As shown, good additive manufacturing and cladding quality can be obtained, and it is particularly suitable for high-throughput additive manufacturing and cladding that require precise control of the composition of the cladding zone.

[0027] 4. This invention also includes a high-throughput powder feeding system. For complex multi-component cladding materials, it is necessary to establish the relationship between components and target properties and obtain a suitable component window. This can be achieved through a high-throughput powder feeding system where the powder feeding motor drives the rotation speed of the powder feeding turntable to control the powder quality. This, combined with a gas flow regulating valve (including a gas pressure reducing valve and a gas flow meter), enables precise control, allowing one or more powder components to change controllably, continuously or abruptly, rather than remaining fixed. This controllable, continuous, or abrupt powder feeding, combined with the parameter settings of the mechanical motion mechanism, can obtain sample arrays with precisely controlled, continuously varying components corresponding to different properties.

[0028] 5. In this invention, sample units with different compositions can be fabricated on the wide-beam cladding band according to the performance to be tested, forming a high-throughput sample array, such as... Figure 5 As shown, it provides a parallel testing and comparison of wear, erosion, and ablation, greatly improving the efficiency of material composition and performance optimization. Attached Figure Description

[0029] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application.

[0030] Figure 1 This is a schematic diagram of the overall structure of the wide-beam high-throughput additive manufacturing and cladding apparatus of the present invention;

[0031] Figure 2 This is a schematic diagram of the air-powder mixing passage structure for synchronous powder feeding according to the present invention;

[0032] Figure 3 This is a schematic diagram of the powder feeding trough structure of the present invention (i.e.) Figure 2 (Enlarged view of the structure of part D in the middle);

[0033] Figure 4 This diagram illustrates the interaction between a wide beam of light and powder ejected from a small rectangular orifice at a rectangular powder delivery outlet.

[0034] Figure 5 Schematic diagram of wide-beam additive manufacturing and cladding strip with high-throughput sample array;

[0035] In the diagram, 1. Powder feeding tank A, 2. Feeding tank B, 3. Powder feeding pipe, 4. Fiber optic interface, 5. Flange mounting plate, 6. Collimating lens, 7. DOE diffractive optical element, 8. Focusing lens, 9. Water cooling interface, 10. Protective lens, 11. Central protective gas, 12. Wide beam spot, 13. Focus adjustment sleeve, 14. Nozzle, 15. Workpiece. Detailed Implementation

[0036] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. However, this is not the only description; all aspects not described in detail herein are based on conventional techniques in the art.

[0037] Example 1

[0038] A wide-beam high-throughput additive manufacturing and cladding apparatus, such as Figure 1 As shown, it includes a wide-beam cladding head, a high-throughput powder feeding system, and a mechanical motion system. The wide-beam cladding head is fixed to the mechanical motion system by a flange mounting plate 5. The high-throughput powder feeding system is used to adjust the quality of the powder delivered, and includes a powder feeding tank A1 and a feeding tank B2.

[0039] The wide-beam spot cladding head includes a laser shaping structure and a gas-powder mixing pathway structure for simultaneous powder feeding, such as... Figure 2 As shown, the laser shaping structure includes a collimating lens 6, a DOE diffractive optical element 7, a focusing lens 8, and a protective lens 10. The synchronous powder feeding gas-powder mixing channel structure includes an optical fiber interface 4, a water-cooling interface 9, a central protective gas 11, a focus adjustment sleeve 13, and a nozzle 14. Powder feeding tanks A1 and B2 are connected to the powder feeding interface of the nozzle through a powder feeding pipe 3. The cooling water pipe of the external chiller is connected to multiple water-cooling interfaces 9 to form a cooling water circulation. The external protective gas is connected to the protective gas interface of the wide-beam spot cladding head to provide the central protective gas 11. The external optical fiber is connected to the optical fiber interface to input the laser. The laser passes through the collimating lens 6, the DOE diffractive optical element 7, the focusing lens 8, and the protective lens 10 in sequence, and outputs a wide-beam spot 12 at the nozzle outlet.

[0040] Both sides of nozzle 14 are equipped with powder feeding troughs. Powder is ejected through the powder feeding troughs, and the outlet of the powder feeding trough is a rectangular powder feeding outlet, which is divided into 7 or more small rectangular holes. The spot width is 20-40mm. Figure 3 As shown.

[0041] To match the width of the discharged powder with the width of the wide powder beam, the conventional circular powder feed outlet was widened to a rectangular powder feed outlet. Furthermore, to ensure uniform powder discharge from the entire rectangular outlet, the overall rectangular opening was divided into multiple smaller rectangular openings, preferably seven. Figure 3Region E is a cross-sectional internal view. To ensure that more powder entering from the center end is distributed, the left and right sides of the rectangular holes are widened. This allows the powder entering from the upper center end to be evenly delivered from the seven small rectangular holes. The powder is ejected from multiple small rectangular holes and fed into the laser beam, where it is fully melted before reaching the working surface. This improves the fusion properties of the powder, reduces the rebound rate on the workpiece surface, and increases the powder utilization rate to 95%. It also achieves good additive manufacturing and cladding quality, making it particularly suitable for high-throughput additive manufacturing and cladding that requires precise control of the composition of the cladding zone.

[0042] The improvements of this invention are twofold: first, the large rectangular hole is divided into seven smaller rectangular holes; second, the upper left and right sides of the rectangular holes are widened, allowing the powder to be evenly delivered from the seven smaller rectangular holes, and smoothly and evenly additively manufactured or clad onto the workpiece under the action of the wide beam spot.

[0043] Example 2

[0044] A wide-beam high-throughput additive manufacturing and cladding apparatus, as described in Example 1, differs in that the high-throughput powder feeding system further includes a powder feeding motor and a powder feeding turntable. The powder feeding motor is installed inside the cabinet of the high-throughput powder feeding system, and the output shaft of the powder feeding motor is connected to the powder feeding turntable. The rotational speed of the powder feeding motor determines the rotational speed of the powder feeding turntable, which is used to control the mass of powder falling into the powder feeding turntable per unit time.

[0045] The pressure of the powder delivery gas is regulated by the gas pressure reducing valve on the external gas supply device (e.g., gas cylinder), and the gas flow rate is regulated by the gas flow meter on the cabinet of the high-throughput powder delivery system. Specifically, the source of the powder delivery gas is the external gas supply device (e.g., gas cylinder). When the main valve on the gas cylinder is opened, the powder delivery gas will pass through the gas pressure reducing valve on the gas cylinder, where the required powder delivery gas pressure is adjusted. Then, it will pass through the gas transmission pipeline to the gas flow meter on the cabinet of the high-throughput powder delivery system, where the required powder delivery gas flow rate is adjusted. Then, it will pass through the gas transmission pipeline to the powder delivery tank, and finally be ejected through the powder delivery pipe. That is, the powder delivery gas will first pass through the powder delivery tank and then through the powder delivery pipe.

[0046] The powder to be additively manufactured and clad is preloaded into powder feeding tanks. There are at least two powder feeding tanks, providing two different powder components. Powder feeding tank A contains a single component or a mixture of components A, and powder feeding tank B contains another single component or a mixture of components B. The powder from powder feeding tank A and powder feeding tank B correspond to two rows of powder feeding grooves (7 small rectangular holes) on both sides of the wide beam nozzle, and reach the nozzle outlet through their respective powder pipelines and powder channels.

[0047] This invention relates to a high-throughput powder feeding system designed to establish the relationship between the composition of multi-component cladding materials and target properties. This results in a continuously varying sample array with precisely controlled composition, corresponding to different properties, enabling the rapid delivery of suitable components for various operating conditions. Precise composition control is achieved through a powder feeding motor driving a powder feeding turntable, combined with a negative pressure powder feeding system using a powder feeding gas. The rotational speed of the powder feeding turntable determines the amount of powder supplied per unit time, while the pressure and flow rate of the powder feeding gas determine the amount of powder carried away per unit time. This combination allows for precise and continuous control of one or more components. When gas-powder mixtures corresponding to different compositions reach the nozzle outlet via their respective powder pipelines and channels, they are fed into the rectangular powder feeding outlet end of the nozzle. After being ejected through multiple small rectangular holes on both sides of the rectangular nozzle, they are simultaneously fed into the laser beam, where they are fully fused and melted before reaching the working area. Combined with the parameter settings of the mechanical motion system of this invention, high-throughput additive manufacturing and cladding can produce sample arrays representing different compositions and properties.

[0048] Example 3

[0049] A method for operating a wide-beam-spot high-throughput additive manufacturing and cladding apparatus: When laser light is input through an external fiber optic interface, the divergent beam from the external fiber enters through the interface and becomes parallel light. It then passes through a DOE diffraction optical element 7, specifically a beam-uniforming element insensitive to the incident beam size and beam quality. The beam is precisely shaped from a circular spot into a rectangular spot. Finally, it passes through a focusing lens 8 and a protective lens 10, and the beam is focused towards the nozzle 14 exit, resulting in a rectangular wide-beam-spot 12 at the nozzle exit. At this point, the focus adjustment sleeve is adjusted... Cylinder 13 aligns the laser focal point (though called a focal point, it is actually a solid rectangular spot, at which point the spot size is smallest and the energy density is highest) with the powder convergence points on both sides. Since the powder on both sides is ejected from two rows of small rectangular holes, it forms two converging lines, causing the laser focal point to be positioned 2mm above and below the powder convergence points. The ejected powder is simultaneously fed into the wide laser beam, where it begins to be heated and melted upon entering the beam. Then, some of the melted powder mixes and interacts with each other. The interaction between the wide beam and the powder ejected from the small rectangular holes at the rectangular powder feeding outlet, such as... Figure 4 As shown, the powder has been fully fused and melted before reaching the workpiece 15, and together with the surface-melted metal workpiece, it forms a molten pool and a cladding layer.

[0050] When the pressure and flow rate of the powder-feeding gas are constant, adjusting the speed of the powder-feeding motor can precisely control the quality of the powder being fed out; similarly, if the pressure of the powder-feeding gas and the speed of the powder-feeding motor are fixed, adjusting the flow rate of the powder-feeding gas can also precisely control the quality of the powder being fed out.

[0051] This invention utilizes gas-driven powder feeding, rather than gravity-driven feeding, based on the principle of negative pressure. The gas flow regulating valve includes a gas pressure reducing valve and a gas flow meter. Gas at a certain pressure is introduced from the inlet of the sealed powder feeding tank and ejected from the outlet. Where the flow velocity is high, the pressure is low, creating a negative pressure along the path of the airflow. This negative pressure draws in the powder from the powder trough of the powder feeding disc and transports it to the workpiece surface along with the airflow. The rotational speed of the powder feeding disc determines the amount of powder supplied per unit time, while the gas pressure and flow rate determine the amount of powder delivered per unit time.

[0052] This invention precisely controls the powder quality delivered from the two powder tanks by adjusting the speed of the powder feeding motor and the pressure and flow rate of the powder feeding air in the powder feeding system.

[0053] During operation, the powder quality from powder feeder A1 remains constant, meaning the powder ratio fed into the molten pool remains unchanged. The powder is ejected from a small rectangular orifice in the powder feed trough on one side of the nozzle. The powder quality from powder feeder B2 changes continuously or abruptly, meaning the powder ratio fed into the molten pool is altered. The powder is ejected from a small rectangular orifice in the powder feed trough on the other side of the nozzle. The change in powder quality from powder feeder B is coordinated with the workpiece 15. The powder ejected from both sides converges in the wide beam cladding zone 12, forming a 20-40mm additive manufacturing or cladding zone after additive cladding. Its composition changes continuously or stepwise, not fixed, achieving high-throughput powder feeding. Sample units with different compositions are processed on the wide beam cladding zone, forming a high-throughput sample array, such as... Figure 5 As shown, it provides a comparative test for wear, erosion, ablation, etc., and provides powerful conditions for quickly screening out the composition window for analyzing the relationship between material composition, structure and properties, greatly improving the optimization efficiency of material composition and properties.

[0054] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A wide-beam high-throughput additive manufacturing and cladding apparatus, characterized in that, It includes a wide-beam cladding head, a high-throughput powder feeding system, and a mechanical motion system. The wide-beam cladding head is fixed to the mechanical motion system by a flange mounting plate. The high-throughput powder feeding system is used to adjust the quality of the powder delivered, and includes powder feeding tank A and material feeding tank B. The wide-beam spot cladding head includes a laser shaping structure and a gas-powder mixing path structure for synchronous powder feeding. The laser shaping structure includes a collimating lens, a DOE diffraction optical element, a focusing lens, and a protective lens. The gas-powder mixing path structure for synchronous powder feeding includes an optical fiber interface, a water-cooling interface, a central protective gas, a focus adjustment sleeve, and a nozzle. Powder feeding tanks A and B are connected to the powder feeding interface of the nozzle through powder feeding pipes. The cooling water pipes of an external chiller are connected to multiple water-cooling interfaces to form a cooling water circulation. An external protective gas is connected to the protective gas interface of the wide-beam spot cladding head to provide central protective gas. An external optical fiber is connected to the optical fiber interface to input laser light. The laser light passes sequentially through the collimating lens, the DOE diffraction optical element, the focusing lens, and the protective lens, and outputs a wide-beam spot at the nozzle outlet. Both sides of the nozzle are provided with powder feeding grooves. Powder is sprayed out through the powder feeding grooves. The outlet of the powder feeding groove is a rectangular powder feeding outlet, which is divided into 7 or more small rectangular holes.

2. The wide-beam high-throughput additive manufacturing and cladding apparatus according to claim 1, characterized in that, The beam width is 20-40mm.

3. The wide-beam high-throughput additive manufacturing and cladding apparatus according to claim 2, characterized in that, The high-throughput powder feeding system also includes a powder feeding motor and a powder feeding turntable. The powder feeding motor is installed inside the cabinet of the high-throughput powder feeding system. The output shaft of the powder feeding motor is connected to the powder feeding turntable. The rotation speed of the powder feeding motor determines the rotation speed of the powder feeding turntable, which is used to control the amount of powder falling into the powder feeding turntable per unit time.

4. The wide-beam high-throughput additive manufacturing and cladding apparatus according to claim 3, characterized in that, The pressure of the powder delivery gas is regulated by the gas pressure reducing valve on the external gas supply device, and the gas flow rate is regulated by the gas flow meter on the cabinet of the high-throughput powder delivery system.

5. The wide-beam high-throughput additive manufacturing and cladding apparatus according to claim 4, characterized in that, There are at least two powder feeding tanks, where powder feeding tank A contains a single component or a mixture of components A, and powder feeding tank B contains another single component or a mixture of components B. The powder from powder feeding tank A and powder feeding tank B correspond to two rows of powder feeding grooves on both sides of the wide beam nozzle, and reach the nozzle outlet through their respective powder pipelines and powder channels.

6. A method of operating the wide-beam high-throughput additive manufacturing and cladding apparatus as described in claim 5, characterized in that, When an external optical fiber is connected to the fiber optic interface to input laser light, the divergent beam transmitted from the external optical fiber enters through the fiber optic interface and becomes parallel light. Then, after passing through the DOE diffraction optical element, the beam is shaped from a circular spot into a rectangular spot. Finally, after passing through the focusing lens and the protective lens, the beam is focused towards the nozzle exit, where a rectangular wide beam spot is obtained. At this time, the focus adjustment sleeve is adjusted to match the laser focus with the powder convergence points on both sides. Since the powder on both sides is ejected from two rows of small rectangular holes, it is actually two converging lines, so that the laser focus is located 2mm above and below the powder convergence point. The ejected powder is simultaneously sent into the laser wide beam spot, and it begins to be heated and melted the moment it enters the wide beam spot. Then, some of the melted powder mixes with each other and is fully fused and melted before reaching the workpiece.

7. The operating method of the wide-beam high-throughput additive manufacturing and cladding apparatus according to claim 6, characterized in that, When the pressure and flow rate of the powder-feeding gas are constant, adjusting the speed of the powder-feeding motor can precisely control the quality of the powder being fed out; if the pressure of the powder-feeding gas and the speed of the powder-feeding motor are fixed, adjusting the flow rate of the powder-feeding gas can also precisely control the quality of the powder being fed out.

8. The operating method of the wide-beam high-throughput additive manufacturing and cladding apparatus according to claim 7, characterized in that, During operation, the powder quality delivered by powder feeding tank A remains constant, meaning the powder ratio fed into the molten pool remains unchanged. The powder is ejected from the small rectangular hole in the powder feeding trough on one side of the nozzle. The powder quality delivered by powder feeding tank B changes continuously or abruptly, meaning the powder ratio fed into the molten pool is changed. The powder is ejected from the small rectangular hole in the powder feeding trough on the other side of the nozzle. The change in the powder quality delivered by powder feeding tank B is coordinated with the workpiece. The powder ejected from both sides converges in a wide beam spot, forming a 20-40mm additive manufacturing band or cladding band after additive cladding. Its composition changes continuously or stepwise, achieving high-throughput powder feeding.

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