A method for three-dimensional manufacturing of metal grains based on double laser powder bed fusion

Abstract

The application discloses a kind of metal grain three-dimensional manufacturing methods based on double laser powder bed melting, method includes the following steps: establishing double laser printing parameter and corresponding metal grain process database and grain and part performance database;Obtain the use performance requirement of metal part to be manufactured, obtain the grain characteristics and distribution of different regions of metal part to be manufactured according to grain and part performance database;To metal part to be manufactured layering is sliced to obtain slice file;Slice file is imported into double laser powder bed melting additive manufacturing equipment, according to process database, different regions of metal part to be manufactured are selected corresponding double laser collaborative printing process parameters, form printing file;Printing file is imported into double laser same plane printing equipment, and metal part to be manufactured is manufactured.The application realizes the regulation of metal grain by changing double laser collaborative parameters, and then realizes integrated manufacturing of part, improves the performance of part while reducing the processing difficulty.

Description

Technical Field

[0001] This invention belongs to the technical field of metal manufacturing and application, and specifically relates to a three-dimensional manufacturing method for metal grains based on dual-laser powder bed melting. Background Technology

[0002] Selective Laser Melting (SLM) technology, with its advantages of adaptability to the forming of complex digital components, flexible and rapid development, and high material utilization, has become an important technical means to solve the bottleneck of high-performance overall manufacturing of complex components. In SLM technology, a laser spot rapidly melts metal powder on a powder bed of a forming platform. Then, the laser spot scans along a preset path, and through a point-line-surface layer-by-layer printing method, a complete metal part is finally formed. During the laser printing process, the laser spot is focused on a point on the metal powder bed, forming a molten pool at that point. The depth and size of the molten pool are often related to the laser parameters. The molten pool moves with the movement of the laser spot, new molten pools are constantly generated, and old molten pools are subsequently solidified, thus melting and solidifying the powder that constitutes the solid metal part into a metal solid structure. Therefore, changes in laser parameters affect the formation of the molten pool, the solidification rate of the molten metal in the molten pool, and the uniformity of the temperature field of the molten metal in the molten pool. These all affect the growth of metal grains in the molten pool, and the growth of metal grains has a significant impact on the performance of the final part.

[0003] With the further application of SLM technology in high-end technology fields such as aerospace, marine engineering, and nuclear power, higher requirements are being placed on the quality and efficiency of the parts produced. Therefore, in recent years, many scholars have conducted research on remelting and heat treatment control for SLM parts used in aerospace and nuclear power, aiming to reduce internal defects and control the uniformity of their microstructure. With the further development of large-size metal additive manufacturing, the existing method of printing the current layer and then remelting not only greatly affects forming efficiency but also leads to uncontrollable remelting time intervals in each region due to inconsistent printing areas per layer. This poses new challenges to the uniformity and consistency of the part's microstructure. Furthermore, existing techniques for controlling the microstructure of parts by changing laser forming parameters have limited effectiveness. Summary of the Invention

[0004] To meet the requirements of modern industry for metal components to possess both high strength and toughness as well as corrosion resistance, this invention addresses the problem that current single-laser powder bed melting and forming methods cannot simultaneously achieve multi-dimensional superior performance in the micro-manufacturing of parts. It provides a three-dimensional manufacturing method for metal grains based on dual-laser powder bed melting.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: The primary objective is to provide a method for three-dimensional manufacturing of metal grains based on dual-laser powder bed melting, comprising the following steps: Based on the relationship between dual-laser printing parameters and metal grain growth, a process database of dual-laser printing parameters and corresponding metal grains is established. The dual-laser printing parameters include dual-laser collaborative scanning mode, dual-laser start-up time interval, first laser power, second laser power, X-axis spacing between the two lasers, Y-axis spacing between the two lasers, first laser spot size, and second laser spot size. The dual-laser collaborative scanning mode includes follow mode and parallel mode. Based on the correspondence between grain characteristics and mechanical and corrosion resistance properties of dual-laser forming materials, a database of grain and part properties is established. Obtain the performance requirements of the metal parts to be manufactured, and obtain the grain characteristics and distribution of different regions of the metal parts to be manufactured based on the grain and part performance database; The metal parts to be manufactured are sliced ​​into layers to obtain slice files; Import the slice file into the dual-laser powder bed fusion additive manufacturing equipment, and select the corresponding dual-laser collaborative printing process parameters for different areas of the metal part to be manufactured according to the process database to form a printing file; Import the printed file into a dual-laser same-format printing device to manufacture the metal parts to be produced.

[0006] As a preferred technical solution, the establishment of a process database of dual-laser printing parameters and corresponding metal grains specifically includes: Based on the single-laser printing process of the prepared material, different combinations of dual-laser printing parameters were designed, and test samples were printed using a dual-laser powder bed fused additive manufacturing equipment. The test sample was prepared by metallography, and the grain morphology was obtained by electron backscatter diffraction. By associating the grain morphology corresponding to different dual-laser printing parameters, a process database of dual-laser printing parameters and corresponding metal grains is obtained.

[0007] As a preferred technical solution, the following mode refers to a working mode in which the second laser beam follows the printing path of the first laser beam during the dual-laser start-up time interval. The relationship between the dual-laser printing parameters and the growth of the metal grains in the following mode is as follows: (1) When the power of the second laser is greater than or equal to the power of the first laser, or when the time interval between the start-up of the two lasers is within the first set time interval, the remelting pool formed by the second laser beam is deeper than the forming pool formed by the first laser beam. The metal grains continue to grow as the solidification front and nucleation point of the previous layer of molten pool grains, forming coarse and continuous metal grains. (2) When the power of the second laser is equal to the power of the first laser multiplied by a set percentage, or when the time interval between the start-up of the two lasers is outside the range of the first set time interval and within the range of the second set time interval, the remelting pool formed by the second laser beam is shallower than the boundary of the forming pool formed by the first laser beam. The metal grains grow upward along the bottom of the forming pool to obtain metal grains with uniform directionality and texture orientation and smaller size. The parallel mode refers to a printing mode in which the first laser beam and the second laser beam print along parallel or approximately parallel printing paths at a dual laser spacing. The relationship between the dual-laser printing parameters and the growth of the metal grains in the parallel mode is as follows: When the sum of the squares of the X-direction spacing and the Y-direction spacing between the two lasers is less than the sum of the squares of the radius of the molten pool formed by the first laser beam, that is, when the first laser beam and the second laser beam act on the same molten pool simultaneously: if the spacing between the two lasers is within the set spacing range, the same molten pool produces metal grains with more continuous vertical growth, stronger texture, and larger vertical dimensions; if the spacing between the two lasers is outside the set spacing range, the same molten pool solidifies to produce metal grains with stronger integrity and larger lateral dimensions.

[0008] As a preferred technical solution, the establishment of the grain and component performance database specifically involves: Based on the single-laser printing process of the prepared material, different combinations of dual-laser printing parameters were designed, and test samples were printed using a dual-laser powder bed fused additive manufacturing equipment. The mechanical and corrosion resistance properties of the printed test samples were tested using a universal testing machine, electrochemical corrosion equipment, and a microhardness tester to obtain the correspondence between the dual-laser printing parameters and the performance of the parts. Based on the dual-laser printing parameters and the corresponding metal grain process database, a grain and part performance database is established.

[0009] As a preferred technical solution, the performance requirements include corrosion resistance, tensile strength, elongation, yield strength, and wear resistance.

[0010] As a preferred technical solution, the slice file is formed by segmenting different regions of the metal part to be manufactured using slicing software.

[0011] As a preferred technical solution, the manufacturing of the metal part to be manufactured specifically involves: Import the print file into the dual-laser same-size printing equipment to form the shape and performance of the metal part in an integrated manner. The dual-laser collaborative printing parameters are set on the dual-laser powder bed fusion additive manufacturing equipment operating software. Identify the dual-laser collaborative printing process parameters and printing path characteristics of the corresponding region in each slice layer of the slice file; Printing begins and continues until all slice layers are formed, resulting in a metal part with a composite of multiple grain morphologies.

[0012] The second objective is to provide a three-dimensional manufacturing system for metal grains based on dual-laser powder bed melting, including a process database construction module, a performance database construction module, a grain feature acquisition module, a layer slicing module, a print file generation module, and a manufacturing module; The process database construction module is used to establish a process database of dual-laser printing parameters and corresponding metal grains based on the relationship between dual-laser printing parameters and metal grain growth. The dual-laser printing parameters include dual-laser collaborative scanning mode, dual-laser start-up time interval, first laser power, second laser power, X-direction spacing between the two lasers, Y-direction spacing between the two lasers, first laser spot size, and second laser spot size. The dual-laser collaborative scanning mode includes follow mode and parallel mode. The performance database construction module is used to establish a performance database of grains and parts based on the correspondence between the grain characteristics and mechanical and corrosion resistance properties of dual-laser forming materials. The grain feature acquisition module is used to obtain the performance requirements of the metal parts to be manufactured, and to obtain the grain characteristics and distribution of different regions of the metal parts to be manufactured based on the grain and part performance database. The layered slicing module is used to slice the metal parts to be manufactured into layers to obtain slice files; The print file generation module is used to import the slice file into the dual-laser powder bed melting additive manufacturing equipment, select the corresponding dual-laser collaborative printing process parameters according to the process database for different areas of the metal part to be manufactured, and generate the print file. The manufacturing module is used to import the print file into the dual-laser same-size printing equipment to manufacture the metal parts to be manufactured.

[0013] The third objective is to provide an electronic device, comprising: At least one processor; and a memory communicatively connected to said at least one processor; wherein, The memory stores computer program instructions that can be executed by the at least one processor to enable the at least one processor to perform the three-dimensional manufacturing method of metal grains based on dual-laser powder bed melting as described above.

[0014] The fourth objective is to provide a computer-readable storage medium storing a program that, when executed by a processor, implements the aforementioned method for three-dimensional manufacturing of metal grains based on dual-laser powder bed melting.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. Increased design freedom for component performance: Existing metal parts are often made from a single material, with different materials applied to the exterior to impart additional properties for different applications. However, this method of coating with other materials cannot adequately cover the part, preventing it from achieving optimal performance. Furthermore, the coating material can peel off or deteriorate due to external environmental factors, affecting normal use. In addition, it is difficult to apply coatings to the interior of parts with complex structural designs. This invention, by altering the synergistic parameters of dual lasers, thereby changing the morphology of the molten pool and controlling the metal grain size, allows for the regional customization of multiple grain structures within a single part. This achieves integrated manufacturing of part shape and properties, improving part performance while reducing processing difficulty.

[0016] 2. Distribution area of ​​the advantageous performance of the parts: This invention designs the metal grains (morphology and texture orientation) of a part in advance, enabling the manufactured part to exhibit different properties in corresponding regions, effectively making the distribution of advantageous regions more rational. Existing parts with multi-dimensional performance requirements require more precise manufacturing processes and are more expensive, and it is often difficult to optimize all performance aspects of parts with multiple performance requirements. In addition, many application scenarios often only have specific requirements for a certain performance of the part, which leads to waste. Therefore, this invention enables the part to have good performance in different application scenarios, which greatly improves the utilization rate of the part and effectively reduces costs. By designing the characteristics (morphology and texture orientation) and distribution of the internal grains in advance, the manufactured part exhibits different properties in corresponding regions, effectively making the distribution of advantageous regions more rational, and finally obtaining a metal sample with multiple grain morphologies.

[0017] 3. It reduces the number of steps involved in manufacturing similar parts using multiple materials in traditional methods: Due to the surge in demand for multi-functional parts across various fields, some researchers have proposed manufacturing metal parts using multi-material powder bed fusion. However, this method requires a multi-material supply system, and the layering of multiple materials during each printing process is complex and difficult. This invention, however, utilizes a digital design and additive manufacturing integrated approach. It requires only one material to create parts with multiple properties, and the metal grains within the part can be designed and adjusted using computer-aided programs. During printing, by simply changing the dual-laser coordination parameters to alter the morphology of the remelted pool and the relative position of the center of the forming pool, metal parts with multiple grain morphologies can be manufactured. This results in parts with extremely high mechanical properties and strong corrosion resistance, meeting diverse application requirements.

[0018] 4. Improved the range and effectiveness of part structure control: While existing methods for microstructure control by altering single-laser process parameters can easily adjust the microstructure of parts, the extremely high laser scanning speed and cooling rate of the metal substrate in metal additive manufacturing make it difficult for a single laser beam to significantly alter the metal's microstructure. This invention employs a dual-laser synergistic scanning method, which can more significantly alter the temperature of the molten pool and the heat-affected zone through the combination of two lasers, thereby achieving a more effective and wider-ranging matrix microstructure control effect. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a flowchart of a three-dimensional manufacturing method for metal grains based on dual-laser powder bed melting in an embodiment of the present invention.

[0021] Figure 2 This is a schematic diagram of dual-laser beam cooperative scanning in follow mode in an embodiment of the present invention.

[0022] Figure 3 The image shows the grain growth results of samples prepared under different dual-laser scanning intervals (50m, 2s) with the same first laser power and second laser power in this embodiment of the invention.

[0023] Figure 4 The figures show the mechanical properties and corrosion resistance of samples with different grain morphologies after dual-laser synergistic control in the embodiments of the present invention.

[0024] Figure 5 This is a schematic diagram of a 316 stainless steel nuclear power plant water-cooling pipe with coarse external grains and small internal grains, controlled by dual lasers in an embodiment of the present invention.

[0025] Figure 6 This is a schematic diagram of the structure of a three-dimensional manufacturing system for metal grains based on dual-laser powder bed melting in an embodiment of the present invention.

[0026] Figure 7 This is a schematic diagram of the structure of an electronic device in an embodiment of the present invention. Detailed Implementation

[0027] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative effort are within the scope of protection of the present application.

[0028] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0029] For ease of explanation, this embodiment uses the dual-laser processing of 316 stainless steel nuclear power plant water-cooling pipes to illustrate the proposed method for three-dimensional manufacturing of metal grains based on dual-laser powder bed melting. Figure 1 As shown, it includes the following steps: S1. Based on the relationship between dual-laser printing parameters and metal grain growth, establish a process database of dual-laser printing parameters and corresponding metal grains; wherein, the dual-laser printing parameters include dual-laser cooperative scanning mode, dual-laser start-up time interval, first laser power, second laser power, X-direction spacing between the two lasers, Y-direction spacing between the two lasers, first laser spot size and second laser spot size; the dual-laser cooperative scanning mode includes follow mode and parallel mode; S2. Based on the correspondence between the grain characteristics and mechanical and corrosion resistance properties of dual-laser forming materials, establish a database of grain and part performance. S3. Obtain the performance requirements of the metal parts to be manufactured, and obtain the grain characteristics and distribution of different regions of the metal parts to be manufactured based on the grain and part performance database. S4. Slice the metal parts to be manufactured into layers to obtain a slice file; S5. Import the slice file into the dual-laser powder bed fusion additive manufacturing equipment, select the corresponding dual-laser collaborative printing process parameters for different areas of the metal part to be manufactured according to the process database, and generate the printing file. S6. Import the print file into the dual-laser same-size printing equipment to manufacture the metal parts to be manufactured.

[0030] Furthermore, to quickly determine the manufacturing process of the parts, a process database can be established based on the material and performance requirements of the parts to be manufactured, so as to quickly match the corresponding dual-laser collaborative printing parameters and improve manufacturing efficiency. Specifically: S101. Based on the single-laser printing process of the prepared material, design different combinations of dual-laser printing parameters, and print test samples using a dual-laser powder bed fused additive manufacturing equipment. S102. The test sample is prepared by metallographic analysis, and the grain morphology is obtained by electron backscatter diffraction. S103. Correlate the corresponding grain morphologies under different dual-laser printing parameters to obtain a process database of dual-laser printing parameters and corresponding metal grains.

[0031] Furthermore, the dual-laser cooperative scanning mode in this application includes a follower mode and a parallel mode. The follower mode refers to the working mode in which the second laser beam follows the printing path of the first laser beam during the dual-laser start-up time interval. In the follower mode, the relationship between the dual-laser printing parameters and the growth of the metal grains is as follows: (1) When the power of the second laser is greater than or equal to the power of the first laser, or when the time interval between the start-up of the two lasers is within the first set time interval, the remelted pool formed by the second laser beam will be deeper than the formed pool formed by the first laser beam. The metal grains will continue to grow as the solidification front and nucleation point of the previous layer of molten pool grains, forming coarse and continuous metal grains. (2) When the power of the first laser is equal to the set percentage (0~1), or when the time interval between the two lasers is outside the range of the first set time interval and within the range of the second set time interval, the remelted pool formed by the second laser beam will be shallower than the boundary of the formed pool formed by the first laser beam. The metal grains grow upwards again along the bottom of the formed pool. However, during the printing process, the direction of the movement path of the two laser beams when scanning each layer will rotate, and the reciprocating scanning strategy is adopted within the layer. This means that the scanning direction of the pool is different from the direction of the three surrounding pools. The independence of the metal grains is enhanced, thus obtaining metal grains with uniform directionality and texture orientation and smaller size.

[0032] Parallel mode refers to a printing mode in which the first and second laser beams follow parallel or nearly parallel printing paths at a dual laser spacing. In parallel mode, the relationship between the dual-laser printing parameters and the growth of metal grains is as follows: When the sum of the squares of the X-direction spacing and the Y-direction spacing between the two lasers is less than the sum of the squares of the radius of the molten pool formed by the first laser beam, that is, when the first laser beam and the second laser beam act on the same molten pool simultaneously: if the spacing between the two lasers is within the set spacing range, the same molten pool receives more energy, and the resulting molten pool has a larger longitudinal dimension, resulting in metal grains with more continuous vertical growth, stronger texture, and larger vertical dimensions; if the spacing between the two lasers is outside the set spacing range, the resulting molten pool has a larger lateral dimension, resulting in metal grains with stronger integrity and larger lateral dimensions produced by the solidification of the same molten pool.

[0033] Since different dual-laser parameters will have different effects on the molten pool morphology, in this embodiment, 316 stainless steel is used as the printing material, and the dual-laser cooperative scanning mode is "follow mode". Figure 2 As shown, both laser beams have a power of 220W and scan at a speed of 1000mm / s. The grain morphology formed by the second laser beam is controlled by changing the input time interval of the second laser beam (single laser, 50ms, 2s), and different metal grain growth conditions are obtained through electron backscatter diffraction. Figure 3 As shown, when forming with a 50ms time interval, the metal grains are relatively coarse; when forming with a 2s time interval, the metal grains are relatively fine because the molten pool is colder and the substrate temperature cools down rapidly.

[0034] Furthermore, the establishment of a grain performance database specifically involves: S201. Based on the single-laser printing process of the prepared material, design different combinations of dual-laser printing parameters, and print test samples using a dual-laser powder bed fused additive manufacturing equipment. S202. The mechanical properties and corrosion resistance of the printed test samples are tested using a universal testing machine, electrochemical corrosion equipment and microhardness tester to obtain the correspondence between the dual laser printing parameters and the performance of the parts. S203. Based on the dual-laser printing parameters and the corresponding metal grain process database, establish a grain and part performance database.

[0035] In this embodiment, the performance of the parts under the corresponding dual-laser printing parameters is obtained by using a universal testing machine and an electrochemical corrosion device, such as... Figure 4 As shown, when forming with a 50ms time interval, the part has good corrosion resistance due to the coarse metal grains, but its tensile strength in the vertical direction is lower than that of the single laser forming sample; when forming with a 2s time interval, the part has high tensile strength in both the horizontal and vertical directions due to the fine metal grains, that is, it has good strength and toughness (mechanical properties).

[0036] Then, based on the performance requirements of different areas of the metal part to be manufactured, the grain characteristics and distribution of different areas of the metal part to be manufactured are designed; among them, the performance requirements include corrosion resistance, tensile strength, elongation, yield strength, and wear resistance. In this embodiment, the performance requirements for the 316 stainless steel nuclear power water-cooling pipe are high strength and toughness in the inner layer and corrosion resistance in the surface layer, therefore, the metal grains are required to be fine grains in the inner layer and coarse grains in the surface layer.

[0037] Furthermore, in this embodiment, Magic slicing software is used to segment and form slice files according to different regions of the metal part to be manufactured; it should also be noted that other slicing software that can achieve the same effect can also be used, and the Magic slicing software used in this example is only for illustrative purposes.

[0038] In this embodiment, Magic slicing software is used to slice the 316 stainless steel nuclear power water-cooling pipe, forming an outer layer of 0.2-1mm thickness, with the remainder being the inner layer, such as... Figure 5 As shown, after slicing, according to the usage requirements, the outer coarse-grained area uses coarse grains to ensure corrosion resistance; the inner fine-grained area uses fine grains to ensure high strength and toughness.

[0039] Furthermore, a CLI format print file containing laser energy and scanning path information is generated.

[0040] In this embodiment, after determining the grain characteristics and distribution of different regions of the metal part to be manufactured, the dual-laser printing parameters are obtained from the process database based on the grain characteristics. For the 316 stainless steel nuclear power water-cooling pipe, a dual-laser collaborative printing forming strategy is adopted for its outer layer, with both the forming laser and the remelting laser having a laser power of 220W and a remelting time interval of 50ms. This forms coarse grains with a low grain boundary density to improve its resistance to intergranular corrosion cracking. For its inner layer, a dual-laser collaborative forming strategy is adopted, with both the forming laser and the remelting laser having a laser power of 220W and a remelting time interval of 2s. This forms fine grains to improve the strength and toughness of the part and reduce the anisotropy of mechanical properties.

[0041] Furthermore, after obtaining the print file, it is input into a dual-laser same-format printing device to manufacture the metal part to be manufactured, specifically as follows: S601. Import the print file into the dual-laser same-size printing equipment to form the shape and performance of the metal parts in an integrated manner. Set the dual-laser collaborative printing parameters on the dual-laser powder bed fusion additive manufacturing equipment operating software. S602. Identify the dual-laser collaborative printing process parameters and printing path characteristics of the corresponding area of ​​each slice layer in the slice file; S603, Start printing until all slice layers are formed, and obtain a metal part with multiple grain morphologies.

[0042] It should be noted that, for the sake of simplicity, the aforementioned method embodiments are all described as a series of actions. However, those skilled in the art should understand that the present invention is not limited to the described order of actions, because according to the present invention, some steps can be performed in other orders or simultaneously.

[0043] Based on the same concept as the three-dimensional manufacturing method of metal grains based on dual-laser powder bed melting in the above embodiments, the present invention also provides a three-dimensional manufacturing system of metal grains based on dual-laser powder bed melting. This system can be used to execute the above-described three-dimensional manufacturing method of metal grains based on dual-laser powder bed melting. For ease of explanation, the structural schematic diagram of the embodiment of the three-dimensional manufacturing system of metal grains based on dual-laser powder bed melting only shows the parts related to the embodiments of the present invention. Those skilled in the art will understand that the illustrated structure does not constitute a limitation on the device, and may include more or fewer components than illustrated, or combine certain components, or have different component arrangements.

[0044] Please see Figure 6 In another embodiment of this application, a three-dimensional manufacturing system for metal grains based on dual-laser powder bed melting is provided, including a process database construction module, a performance database construction module, a grain feature acquisition module, a layer slicing module, a print file formation module, and a manufacturing module; The process database construction module is used to establish a process database of dual-laser printing parameters and corresponding metal grains based on the relationship between dual-laser printing parameters and metal grain growth. The dual-laser printing parameters include dual-laser cooperative scanning mode, dual-laser start-up time interval, first laser power, second laser power, X-direction spacing between the two lasers, Y-direction spacing between the two lasers, first laser spot size, and second laser spot size. The dual-laser cooperative scanning mode includes follow mode and parallel mode. The performance database construction module is used to establish a performance database of grains and parts based on the correspondence between the grain characteristics and mechanical and corrosion resistance properties of dual-laser forming materials. The grain feature acquisition module is used to obtain the performance requirements of the metal parts to be manufactured, and to obtain the grain characteristics and distribution of different regions of the metal parts to be manufactured based on the grain and part performance database. The layer slicing module is used to slice the metal parts to be manufactured into layers, and obtain slice files. The print file generation module is used to import the slice file into the dual-laser powder bed fusion additive manufacturing equipment, select the corresponding dual-laser collaborative printing process parameters according to the process database for different areas of the metal part to be manufactured, and generate the print file. The manufacturing module is used to import print files into a dual-laser same-format printing device to manufacture the metal parts to be manufactured.

[0045] It should be noted that the metal grain three-dimensional manufacturing system based on dual-laser powder bed melting of the present invention corresponds one-to-one with the metal grain three-dimensional manufacturing method based on dual-laser powder bed melting of the present invention. The technical features and beneficial effects described in the embodiments of the metal grain three-dimensional manufacturing method based on dual-laser powder bed melting are applicable to the embodiments of the metal grain three-dimensional manufacturing system based on dual-laser powder bed melting. For details, please refer to the description in the embodiments of the method of the present invention, which will not be repeated here.

[0046] Furthermore, in the embodiments of the metal grain three-dimensional manufacturing system based on dual-laser powder bed melting described above, the logical division of each program module is merely an example. In actual applications, the above functions can be assigned to different program modules as needed, for example, for the sake of corresponding hardware configuration requirements or the convenience of software implementation. That is, the internal structure of the metal grain three-dimensional manufacturing system based on dual-laser powder bed melting can be divided into different program modules to complete all or part of the functions described above.

[0047] Please see Figure 7 In one embodiment, an electronic device is provided for implementing a three-dimensional manufacturing method for metal grains based on dual-laser powder bed melting. The electronic device may include a first processor, a first memory, and a bus, and may also include a computer program stored in the first memory and executable on the first processor, such as a three-dimensional manufacturing program for metal grains based on dual-laser powder bed melting.

[0048] The first memory includes at least one type of readable storage medium, such as flash memory, portable hard drive, multimedia card, card-type memory (e.g., SD or DX memory), magnetic memory, disk, optical disk, etc. In some embodiments, the first memory can be an internal storage unit of an electronic device, such as a portable hard drive. In other embodiments, the first memory can be an external storage device of the electronic device, such as a plug-in portable hard drive, smart media card (SMC), secure digital card (SD), flash card, etc. Furthermore, the first memory can include both internal and external storage units of the electronic device. The first memory can be used not only to store application software and various types of data installed on the electronic device, such as code for a three-dimensional manufacturing program of metal grains based on dual-laser powder bed melting, but also to temporarily store data that has been output or will be output.

[0049] In some embodiments, the first processor may be composed of integrated circuits, such as a single packaged integrated circuit or multiple integrated circuits with the same or different functions, including combinations of one or more central processing units (CPUs), microprocessors, digital processing chips, graphics processors, and various control chips. The first processor is the control unit of the electronic device, connecting various components of the entire electronic device through various interfaces and lines. It executes programs or modules stored in the first memory (e.g., a three-dimensional manufacturing program for metal grains based on dual-laser powder bed melting) and calls data stored in the first memory to perform various functions of the electronic device and process data.

[0050] Figure 7 Only electronic devices with components are shown; it will be understood by those skilled in the art that... Figure 7 The structure shown does not constitute a limitation on the electronic device and may include fewer or more components than shown, or combine certain components, or have different component arrangements.

[0051] The three-dimensional manufacturing program for metal grains based on dual-laser powder bed melting, stored in the first memory of the electronic device, is a combination of multiple instructions. When run in the first processor, it can achieve the following: Based on the relationship between dual-laser printing parameters and metal grain growth, a process database of dual-laser printing parameters and corresponding metal grains is established. The dual-laser printing parameters include dual-laser cooperative scanning mode, dual-laser start-up time interval, first laser power, second laser power, X-axis spacing between the two lasers, Y-axis spacing between the two lasers, first laser spot size, and second laser spot size. The dual-laser cooperative scanning mode includes follow mode and parallel mode. Based on the correspondence between grain characteristics and mechanical and corrosion resistance properties of dual-laser forming materials, a database of grain and part properties is established. Obtain the performance requirements of the metal parts to be manufactured, and obtain the grain characteristics and distribution of different regions of the metal parts to be manufactured based on the grain and part performance database; The metal parts to be manufactured are sliced ​​into layers to obtain slice files; Import the slice file into the dual-laser powder bed fusion additive manufacturing equipment, and select the corresponding dual-laser collaborative printing process parameters for different areas of the metal part to be manufactured according to the process database to form a printing file; Import the printed file into a dual-laser same-format printing device to manufacture the metal parts to be produced.

[0052] Furthermore, if the modules / units integrated in the electronic device are implemented as software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium. The computer-readable medium may include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, or a read-only memory (ROM).

[0053] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0054] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0055] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for three-dimensional manufacturing of metal grains based on dual-laser powder bed melting, characterized in that, Includes the following steps: Based on the relationship between dual-laser printing parameters and metal grain growth, a process database of dual-laser printing parameters and corresponding metal grains is established. The dual-laser printing parameters include dual-laser collaborative scanning mode, dual-laser start-up time interval, first laser power, second laser power, X-axis spacing between the two lasers, Y-axis spacing between the two lasers, first laser spot size, and second laser spot size. The dual-laser collaborative scanning mode includes a following mode and a parallel mode. The following mode refers to the working mode where the second laser beam follows the printing path of the first laser beam within the dual-laser start-up time interval. The parallel mode refers to the working mode where, under the dual-laser spacing, the first and second laser beams print along parallel or approximately parallel printing paths. The relationship between the dual-laser printing parameters and the growth of metal grains in the follow-up mode is as follows: (1) When the power of the second laser is greater than or equal to the power of the first laser, or when the time interval between the start-up of the two lasers is within the first set time interval, the remelting pool formed by the second laser beam is deeper than the forming pool formed by the first laser beam. The metal grains continue to grow as the solidification front and nucleation point of the previous layer of molten pool grains, forming coarse and continuous metal grains. (2) When the power of the second laser is equal to the power of the first laser multiplied by a set percentage, or when the time interval between the two lasers is outside the range of the first set time interval and within the range of the second set time interval, the remelted pool formed by the second laser beam is shallower than the boundary of the formed pool formed by the first laser beam, and the metal grains grow upward along the bottom of the formed pool to obtain metal grains with uniform directionality and texture orientation and smaller size; the set percentage ranges from 0 to 1. The relationship between the dual-laser printing parameters and the growth of metal grains in the parallel mode is as follows: When the sum of the squares of the X-direction spacing and the Y-direction spacing between the two lasers is less than the sum of the squares of the radius of the molten pool formed by the first laser beam, that is, when the first laser beam and the second laser beam act on the same molten pool simultaneously: if the spacing between the two lasers is within the set spacing range, the same molten pool produces metal grains with more continuous vertical growth, stronger texture, and larger vertical dimensions; if the spacing between the two lasers is outside the set spacing range, the same molten pool solidifies to produce metal grains with stronger integrity and larger lateral dimensions. Based on the correspondence between the grain characteristics, mechanical properties, and corrosion resistance of dual-laser forming materials, a database of grain and part performance is established. Obtain the performance requirements of the metal parts to be manufactured, and obtain the grain characteristics and distribution of different regions of the metal parts to be manufactured based on the grain and part performance database; The metal parts to be manufactured are sliced ​​into layers to obtain slice files; Import the slice file into the dual-laser powder bed fusion additive manufacturing equipment, and select the corresponding dual-laser collaborative printing process parameters for different areas of the metal part to be manufactured according to the process database to form a printing file; Import the printed file into a dual-laser same-format printing device to manufacture the metal parts to be produced.

2. The method for three-dimensional manufacturing of metal grains based on dual-laser powder bed melting according to claim 1, characterized in that, The establishment of the process database for dual-laser printing parameters and corresponding metal grains specifically involves: Based on the single-laser printing process of the prepared material, different combinations of dual-laser printing parameters were designed, and test samples were printed using a dual-laser powder bed fused additive manufacturing equipment. The test sample was prepared by metallography, and the grain morphology was obtained by electron backscatter diffraction. By associating the grain morphology corresponding to different dual-laser printing parameters, a process database of dual-laser printing parameters and corresponding metal grains is obtained.

3. The method for three-dimensional manufacturing of metal grains based on dual-laser powder bed melting according to claim 1, characterized in that, The establishment of the grain and component performance database specifically involves: Based on the single-laser printing process of the prepared material, different combinations of dual-laser printing parameters were designed, and test samples were printed using a dual-laser powder bed fused additive manufacturing equipment. The mechanical and corrosion resistance properties of the printed test samples were tested using a universal testing machine, electrochemical corrosion equipment, and a microhardness tester to obtain the correspondence between the dual-laser printing parameters and the performance of the parts. Based on the dual-laser printing parameters and the corresponding metal grain process database, a grain and part performance database is established.

4. The method for three-dimensional manufacturing of metal grains based on dual-laser powder bed melting according to claim 1, characterized in that, The performance requirements include corrosion resistance, tensile strength, elongation, yield strength, and abrasion resistance.

5. The method for three-dimensional manufacturing of metal grains based on dual-laser powder bed melting according to claim 1, characterized in that, The slice file is generated by segmenting the metal part to be manufactured using slicing software.

6. The method for three-dimensional manufacturing of metal grains based on dual-laser powder bed melting according to claim 1, characterized in that, The manufacturing of the metal parts to be manufactured specifically includes: Import the print file into the dual-laser same-size printing equipment to form the shape and performance of the metal part in an integrated manner. The dual-laser collaborative printing parameters are set on the dual-laser powder bed fusion additive manufacturing equipment operating software. Identify the dual-laser collaborative printing process parameters and printing path characteristics of the corresponding region in each slice layer of the slice file; Printing begins and continues until all slice layers are formed, resulting in a metal part with a composite of multiple grain morphologies.

7. A three-dimensional manufacturing system for metal grains based on dual-laser powder bed melting, characterized in that, The system includes a process database construction module, a performance database construction module, a grain feature acquisition module, a layered slicing module, a print file generation module, and a manufacturing module; The process database construction module is used to establish a process database of dual-laser printing parameters and corresponding metal grains based on the relationship between dual-laser printing parameters and metal grain growth. The dual-laser printing parameters include dual-laser cooperative scanning mode, dual-laser start-up time interval, first laser power, second laser power, X-direction spacing between the two lasers, Y-direction spacing between the two lasers, first laser spot size, and second laser spot size. The dual-laser cooperative scanning mode includes a follow mode and a parallel mode. The follow mode refers to the working mode in which the second laser beam follows the printing path of the first laser beam during the dual-laser start-up time interval. The parallel mode refers to the working mode in which the first laser beam and the second laser beam print along parallel or approximately parallel printing paths under the dual-laser spacing. The relationship between the dual-laser printing parameters and the growth of metal grains in the follow-up mode is as follows: (1) When the power of the second laser is greater than or equal to the power of the first laser, or when the time interval between the start-up of the two lasers is within the first set time interval, the remelting pool formed by the second laser beam is deeper than the forming pool formed by the first laser beam. The metal grains continue to grow as the solidification front and nucleation point of the previous layer of molten pool grains, forming coarse and continuous metal grains. (2) When the power of the second laser is equal to the power of the first laser multiplied by a set percentage, or when the time interval between the two lasers is outside the range of the first set time interval and within the range of the second set time interval, the remelted pool formed by the second laser beam is shallower than the boundary of the formed pool formed by the first laser beam, and the metal grains grow upward along the bottom of the formed pool to obtain metal grains with uniform directionality and texture orientation and smaller size; the set percentage ranges from 0 to 1. The relationship between the dual-laser printing parameters and the growth of metal grains in the parallel mode is as follows: When the sum of the squares of the X-direction spacing and the Y-direction spacing between the two lasers is less than the sum of the squares of the radius of the molten pool formed by the first laser beam, that is, when the first laser beam and the second laser beam act on the same molten pool simultaneously: if the spacing between the two lasers is within the set spacing range, the same molten pool produces metal grains with more continuous vertical growth, stronger texture, and larger vertical dimensions; if the spacing between the two lasers is outside the set spacing range, the same molten pool solidifies to produce metal grains with stronger integrity and larger lateral dimensions. The performance database construction module is used to establish a performance database of grains and parts based on the correspondence between the grain characteristics, mechanical properties, and corrosion resistance of dual-laser forming materials. The grain feature acquisition module is used to obtain the performance requirements of the metal parts to be manufactured, and to obtain the grain characteristics and distribution of different regions of the metal parts to be manufactured based on the grain and part performance database. The layered slicing module is used to slice the metal parts to be manufactured into layers to obtain slice files; The print file generation module is used to import the slice file into the dual-laser powder bed melting additive manufacturing equipment, select the corresponding dual-laser collaborative printing process parameters according to the process database for different areas of the metal part to be manufactured, and generate the print file. The manufacturing module is used to import the print file into the dual-laser same-size printing equipment to manufacture the metal parts to be manufactured.

8. An electronic device, characterized in that, The electronic device includes: At least one processor; and a memory communicatively connected to said at least one processor; wherein, The memory stores computer program instructions that can be executed by the at least one processor to enable the at least one processor to perform the three-dimensional manufacturing method of metal grains based on dual-laser powder bed melting as described in any one of claims 1-6.

9. A computer-readable storage medium storing a program, characterized in that, When the program is executed by the processor, it implements the three-dimensional manufacturing method for metal grains based on dual-laser powder bed melting as described in any one of claims 1-6.

Images