Metal grain three-dimensional manufacturing method based on double-laser powder bed melting

Abstract

The invention discloses a metal grain three-dimensional manufacturing method based on double-laser powder bed melting. The method comprises the following steps that a double-laser printing parameter and corresponding metal grain process database and a grain and part performance database are established; obtaining use performance requirements of the to-be-manufactured metal part, and obtaining grain characteristics and distribution of different areas of the to-be-manufactured metal part according to the grain and part performance database; layering and slicing the to-be-manufactured metal part to obtain a slice file; the slice file is imported into double-laser powder bed melting additive manufacturing equipment, corresponding double-laser collaborative printing process parameters are selected for different areas of the to-be-manufactured metal part according to a process database, and a printing file is formed; and the printing file is imported into double-laser same-breadth printing equipment, and the metal part to be manufactured is manufactured. According to the method, the metal grains are regulated and controlled by changing the dual-laser collaborative parameters, then integrated manufacturing of parts is achieved, and the machining difficulty is reduced while the performance of the parts is improved.

Description

Technical Field

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

[0002] Selective laser melting (SLM) has the characteristics of adapting to the formation of digital complex components, flexible and rapid development, and high material utilization. It has now become an important technical means to solve the bottleneck of high-performance overall manufacturing of complex components. In SLM technology, the laser spot quickly melts the metal powder on the powder bed of the forming platform, and then the laser spot scans according to the preset path, and finally forms a complete metal component through the point-line-surface layer-by-layer printing method; during the laser printing process, the laser spot is focused on a point on the metal powder bed, and a molten pool is formed at this 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 spot, and a new molten pool is continuously generated, and the old molten pool solidifies immediately, so that the powder constituting the metal part entity is melted and solidified into a metal entity organization; therefore, the change of laser parameters will affect the generation of the molten pool, the solidification rate of the molten metal in the molten pool, and the uniformity of the molten temperature field in the molten pool, which will affect the growth of metal grains in the molten pool, and the growth of metal grains has an important influence on the performance of the final component.

[0003] With the further application of SLM technology in high-end technology fields such as aerospace, marine ships, and nuclear power, higher requirements are placed on the quality and efficiency of the parts produced. Therefore, in recent years, many scholars have conducted research on remelting, heat treatment regulation, etc. for SLM parts used in aerospace, nuclear power and other fields, aiming to reduce internal defects of parts and regulate the uniformity of their microstructure. With the further development of large-scale metal additive manufacturing, the existing method of completing the current layer printing and then remelting will not only greatly affect the forming efficiency, but also cause the remelting time interval of each area to be uncontrollable due to the inconsistent printing area of ​​each layer of the part, which poses new challenges to the uniformity and consistency of the part's organization. In addition, the existing technology of changing the laser forming parameters has limited effect on the regulation of the microstructure of parts. Summary of the invention

[0004] In order to meet the requirements of modern industry for metal components to have both high strength and toughness and corrosion resistance, the present invention provides a three-dimensional manufacturing method of metal grains based on dual laser powder bed melting, aiming at the problem that the current single laser powder bed melting forming of metal cannot solve the problem that parts cannot have multi-dimensional excellent performance during micro-manufacturing.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: The first object is to provide a three-dimensional manufacturing method of metal grains based on dual laser powder bed fusion, comprising the following steps: According to the relationship between the dual laser printing parameters and the growth of metal grains, a process database of the dual laser printing parameters and the corresponding metal grains is established; the dual laser printing parameters include a dual laser collaborative scanning mode, a dual laser start time interval, a first laser power, a second laser power, an X-direction spacing between the dual lasers, a Y-direction spacing between the dual lasers, a first laser spot size, and a second laser spot size; the dual laser collaborative scanning mode includes a follow-up mode and a parallel mode; According to 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 areas of the metal parts to be manufactured based on the grain and part performance database; Carry out layered slicing on the metal parts to be manufactured to obtain slicing files; 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 parts to be manufactured according to the process database, and form a printing file; The printing file is imported into the dual laser same-format printing device to manufacture the metal parts to be manufactured.

[0006] As a preferred technical solution, the process database of dual laser printing parameters and corresponding metal grains is established as follows: According to the single laser printing process of the prepared material, different combinations of dual laser printing parameters are designed, and test samples are printed by dual laser powder bed fusion additive manufacturing equipment; The test samples were metallographically prepared and the grain morphology was obtained by electron backscatter diffraction; The corresponding grain morphologies under different dual laser printing parameters are associated to obtain a process database of dual laser printing parameters and corresponding metal grains.

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

[0008] As a preferred technical solution, the establishment of a grain and component performance database is specifically as follows: According to the single laser printing process of the prepared material, different combinations of dual laser printing parameters are designed, and test samples are printed by dual laser powder bed fusion additive manufacturing equipment; The mechanical properties and corrosion resistance of the printed test samples were tested using a universal testing machine, electrochemical corrosion equipment, and a microhardness tester to obtain the corresponding relationship between dual laser printing parameters and part performance; According to the dual laser printing parameters and the process database of the corresponding metal grains, 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 slicing file is formed by segmenting the metal part to be manufactured using slicing software according to different regions.

[0011] As a preferred technical solution, the metal parts to be manufactured are manufactured as follows: Import the printing file into the dual-laser same-format printing equipment, integrate the shape and performance of the metal parts, and set the dual-laser collaborative printing parameters 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 area of ​​each slice layer in the slice file; Printing starts until all slice layers are formed, and a metal part with a composite of multiple grain morphologies is obtained.

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

[0013] The third object is to provide an electronic device, comprising: at least one processor; and a memory in communication with the at least one processor; wherein, The memory stores computer program instructions that can be executed by the at least one processor, and the computer program instructions are 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 fusion as described above.

[0014] The fourth purpose is to provide a computer-readable storage medium storing a program, which, when executed by a processor, implements the above-mentioned three-dimensional manufacturing method of metal grains based on dual laser powder bed fusion.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. Improved the performance design freedom of parts: Existing metal parts are often made of a single material, and corresponding materials are coated on the outside of the parts in different usage scenarios to give them other properties; however, since the coating method of other materials cannot cover the parts well, the performance of the parts cannot reach the best, and the coating materials may fall off or deteriorate due to external environmental reasons, affecting normal use. In addition, it is also difficult to coat the inside of parts with complex structural designs. The present invention achieves the regulation of metal grains by changing the dual laser collaborative parameters and then changing the morphology of the molten pool, so that a part can achieve regional customization of multiple grain structures, realizing the integrated manufacturing of part shape and properties, improving part performance while reducing processing difficulty.

[0016] 2. Advantageous performance distribution area of ​​parts: The present invention designs the metal grains (morphology, texture orientation) of the parts in advance, so that the manufactured parts can show different properties in the corresponding areas, and effectively make the distribution of the advantageous areas more reasonable. Existing parts with multi-dimensional performance requirements require more sophisticated manufacturing processes and higher prices, and parts with multiple performance requirements often find it difficult to optimize all performance. In addition, many usage scenarios often only have special requirements for a certain performance of the parts, which causes waste. Therefore, the present invention can make the parts have better performance in different application scenarios, which greatly improves the utilization rate of the parts and effectively reduces the cost; by designing the characteristics (morphology, texture orientation) and distribution of the internal grains in advance, the manufactured parts can show different properties in the corresponding areas, effectively making the distribution of the advantageous areas more reasonable, and finally obtaining metal samples with a composite of multiple grain morphologies.

[0017] 3. Reduce the steps of traditional multi-material manufacturing of the same type of parts: Due to the sharp increase in demand for parts with multiple properties in many fields, scholars have proposed in recent years to manufacture metal parts by using a multi-material powder bed fusion method, but this method requires a multi-material supply system. In addition, each layer of printing involves the cladding of multiple materials, and the manufacturing process is complicated and difficult to operate. The present invention uses digital design and additive manufacturing integrated forming, and only needs to use one material to make the parts have multiple properties, and the metal grains in the parts can be designed and adjusted through computer-aided programs. During the printing process, it is only necessary to change the dual laser collaborative parameters to achieve the change of the relative position of the remelting molten pool to the center of the forming molten pool, so as to complete the production of metal parts with multiple grain forms, that is, the parts can have extremely high mechanical properties and strong corrosion resistance to meet the requirements of diversified use.

[0018] 4. Improved the scope and effect of parts organization regulation: Although the existing organizational control method of changing the single laser process parameters can simply adjust the microstructure of parts, due to the extremely fast laser scanning speed and the extremely high cooling rate of the metal matrix in metal additive manufacturing, it is difficult for a single laser energy beam to significantly change the microstructure of the metal. The present invention adopts a dual-laser collaborative scanning method, which can significantly change the temperature of the molten pool and the heat-affected zone through the combination of dual lasers, thereby obtaining a more effective matrix organizational control effect with a wider range of influence. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

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

[0021] Figure 2 Schematic diagram of dual laser beam cooperative scanning in follow-up mode in an embodiment of the present invention.

[0022] Figure 3 This is a graph showing the grain growth results of samples prepared at different dual laser scanning intervals (50m, 2s) under the same first laser power and second laser power in an embodiment of the present invention.

[0023] Figure 4 This is a performance result diagram of mechanical properties and corrosion resistance of samples with different grain morphologies after dual laser collaborative regulation in an embodiment of the present invention.

[0024] Figure 5 Schematic diagram of a 316 stainless steel nuclear power water cooling pipeline with external coarse grains and internal small grains controlled by dual laser synergistic control in an embodiment of the present invention.

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

[0026] Figure 7 Schematic diagram of the structure of an electronic device in an embodiment of the present invention. DETAILED DESCRIPTION

[0027] In order 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 in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application.

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

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

[0030] Furthermore, in order to quickly determine the manufacturing process of parts, a process database can be established according to the material and performance requirements of the required parts to quickly match the corresponding dual-laser collaborative printing parameters to improve manufacturing efficiency, specifically: S101. Designing different combinations of dual laser printing parameters according to the single laser printing process of the prepared material, and printing test samples through a dual laser powder bed fusion additive manufacturing device; S102, performing metallographic preparation on the test sample, and obtaining the grain morphology through electron backscatter diffraction; S103 , associating 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 collaborative scanning mode in the present application includes a follow mode and a parallel mode, wherein the follow mode refers to a working mode in which the second laser beam follows the printing path of the first laser beam to print within the dual laser start time interval. In the follow mode, the relationship between the dual laser printing parameters and the growth of the metal grains is: (1) When the second laser power is greater than or equal to the first laser power, or the dual laser start-up time interval is within the first set time interval range, the remelting molten pool formed by the second laser beam will be deeper than the forming molten pool formed by the first laser beam, and the metal grains will continue to grow with the previous layer of molten pool grains as the solidification front and nucleation point, forming coarse and continuous metal grains; (2) When it is equal to the first laser power * the set percentage (0-1), or when the dual laser start time interval is outside the first set time interval range and within the second set time interval range, the remelting molten pool formed by the second laser beam will be shallower than the boundary of the forming molten pool formed by the first laser beam, and the metal grains will grow upward along the bottom of the forming molten pool. However, during the printing process, the direction of the movement path of the dual laser beams will rotate when scanning each layer, and a reciprocating scanning strategy is adopted within the layer, which means that the scanning direction of the molten pool is different from the directions of the surrounding three molten pools. The independence of the metal grains is enhanced, so that metal grains with uniform directionality and texture orientation and smaller size are obtained.

[0032] The parallel mode refers to a working mode in which the first laser beam and the second laser beam print in parallel or approximately parallel printing paths under the dual laser spacing. In the parallel mode, the relationship between the dual laser printing parameters and the growth of metal grains is: When the sum of the squares of the X-direction spacing between the dual lasers and the Y-direction spacing between the dual 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 at the same time: if the dual laser spacing is within the set spacing range, the same molten pool obtains more energy, and the formed molten pool has a larger longitudinal size, which will produce metal grains with more continuous vertical growth, stronger texture, and larger vertical size; if the dual laser spacing is outside the set spacing range, the formed molten pool has a larger transverse size, and metal grains with stronger integrity and larger transverse size are produced by 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 collaborative scanning mode is the "following mode", such as Figure 2 As shown in the figure, the power of both laser beams is 220W, and they are scanned at a speed of 1000mm / s; and by changing the time interval of the second laser beam input in the dual laser beams (single laser, 50ms, 2s), the grain morphology formed by the second laser beam is regulated, and different metal grain growth conditions are obtained through electron backscatter diffraction. Figure 3 As shown in the figure, when the forming time interval is 50ms, the metal grains are relatively coarse; when the forming time interval is 2s, the molten pool is relatively cold, the substrate temperature cools down quickly, and the metal grains are relatively fine.

[0034] Furthermore, the grain performance database is established as follows: S201. Designing different combinations of dual laser printing parameters according to the single laser printing process of the prepared material, and printing out test samples through a dual laser powder bed fusion additive manufacturing device; S202, testing the mechanical properties and corrosion resistance of the printed test samples by using a universal testing machine, an electrochemical corrosion device and a microhardness tester, and obtaining the corresponding relationship between the dual laser printing parameters and the part performance; S203, establishing a crystal grain and part performance database according to the dual laser printing parameters and the process database of the corresponding metal crystal grains.

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

[0036] Then, according to the performance requirements of different regions of the metal parts to be manufactured, the grain characteristics and distribution of different regions of the metal parts to be manufactured are designed; wherein the performance requirements include corrosion resistance, tensile strength, elongation, yield strength and wear resistance, etc. In this embodiment, the performance requirements of the 316 stainless steel nuclear power water cooling pipeline are high strength and toughness of the inner layer and corrosion resistance of the surface layer, so the metal grains are required to have fine grains in the inner layer and coarse grains on the surface layer.

[0037] Furthermore, in this embodiment, Magic slicing software is used to segment different areas of the metal parts to be manufactured to form slicing files; 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 exemplary purposes.

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

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

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

[0041] Furthermore, after obtaining the printing file, the printing file is input into the dual laser same-format printing device to manufacture the metal parts to be manufactured, specifically: S601, importing the printing file into the dual-laser same-format printing device, integrating the shape and performance of the metal parts, and setting the dual-laser collaborative printing parameters on the dual-laser powder bed fusion additive manufacturing equipment operating software; S602, identifying 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 a composite of multiple grain morphologies.

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

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

[0044] See also Figure 6 , in another embodiment of the present application, there is provided a metal grain three-dimensional manufacturing system based on dual laser powder bed fusion, including a process database building module, a performance database building module, a grain feature acquisition module, a layered slicing module, a print file forming module, and a manufacturing module; Among them, the process database construction module is used to establish a process database of dual laser printing parameters and corresponding metal grains according to the growth relationship between dual laser printing parameters and metal grains; the dual laser printing parameters include dual laser collaborative scanning mode, dual laser start time interval, first laser power, second laser power, X-direction spacing between dual lasers, Y-direction spacing between dual lasers, first laser spot size and second laser spot size; dual laser collaborative scanning mode includes follow-up mode and parallel mode; The performance database construction module is used to establish a grain and part performance database based on the correspondence between the grain characteristics and 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 obtain the grain characteristics and distribution of different areas of the metal parts to be manufactured according to the grain and part performance database; The layered slicing module is used to perform layered slicing on the metal parts to be manufactured and obtain slicing files; The printing file forming 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 for different areas of the metal parts to be manufactured according to the process database, and form the printing file; The manufacturing module is used to import the printing files into the dual laser same-format printing equipment 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 embodiment of the metal grain three-dimensional manufacturing method based on dual laser powder bed melting are applicable to the embodiment of the metal grain three-dimensional manufacturing system based on dual laser powder bed melting. For specific contents, please refer to the description in the embodiment of the method of the present invention, which will not be repeated here. This is hereby declared.

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

[0047] See also Figure 7 In one embodiment, an electronic device for implementing a method for three-dimensional manufacturing of metal grains based on dual laser powder bed fusion is provided. 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 fusion.

[0048] Wherein, the first memory includes at least one type of readable storage medium, and the readable storage medium includes flash memory, mobile hard disk, multimedia card, card-type memory (for example: SD or DX memory, etc.), magnetic memory, disk, optical disk, etc. In some embodiments, the first memory may be an internal storage unit of an electronic device, such as a mobile hard disk of the electronic device. In other embodiments, the first memory may also be an external storage device of an electronic device, such as a plug-in mobile hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (SecureDigital, SD) card, a flash card (Flash Card), etc. equipped on the electronic device. Further, the first memory may also include both an internal storage unit of the electronic device and an external storage device. The first memory can be used not only to store application software and various types of data installed in the electronic device, such as the code of the metal grain three-dimensional manufacturing program based on dual laser powder bed melting, but also to temporarily store data that has been output or is to be output.

[0049] In some embodiments, the first processor may be composed of an integrated circuit, for example, a single packaged integrated circuit, or a plurality of packaged integrated circuits with the same or different functions, including one or more central processing units (CPUs), microprocessors, digital processing chips, graphics processors, and combinations of various control chips, etc. The first processor is the control core (ControlUnit) of the electronic device, and uses various interfaces and lines to connect various components of the entire electronic device, and executes various functions and processes data of the electronic device by running or executing programs or modules stored in the first memory (for example, a three-dimensional manufacturing program for metal grains based on dual laser powder bed fusion, etc.), and calling data stored in the first memory.

[0050] Figure 7 Only an electronic device with components is shown, and those skilled in the art will understand that Figure 7 The structure shown does not constitute a limitation on the electronic device, and may include fewer or more components than shown in the figure, or combine certain components, or arrange the components differently.

[0051] The metal grain three-dimensional manufacturing program based on dual laser powder bed fusion stored in the first memory of the electronic device is a combination of multiple instructions, and when running in the first processor, it can achieve: According to the relationship between the dual laser printing parameters and the growth of metal grains, a process database of dual laser printing parameters and corresponding metal grains is established; wherein the dual laser printing parameters include dual laser collaborative scanning mode, dual laser start time interval, first laser power, second laser power, X-direction spacing between dual lasers, Y-direction spacing between dual lasers, first laser spot size and second laser spot size; dual laser collaborative scanning mode includes follow-up mode and parallel mode; According to 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 areas of the metal parts to be manufactured based on the grain and part performance database; Carry out layered slicing on the metal parts to be manufactured to obtain slicing files; 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 parts to be manufactured according to the process database, and form a printing file; The printing file is imported into the dual laser same-format printing device to manufacture the metal parts to be manufactured.

[0052] Furthermore, if the module / unit integrated in the electronic device is implemented in the form of a software functional unit and sold or used as an independent product, it 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 mobile hard disk, a magnetic disk, an optical disk, a computer memory, and a read-only memory (ROM).

[0053] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0054] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, 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 implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A three-dimensional manufacturing method for metal grains based on dual laser powder bed fusion, characterized in that: The steps include: According to the relationship between the dual laser printing parameters and the growth of metal grains, a process database of the dual laser printing parameters and the corresponding metal grains is established; the dual laser printing parameters include a dual laser collaborative scanning mode, a dual laser start time interval, a first laser power, a second laser power, an X-direction spacing between the dual lasers, a Y-direction spacing between the dual lasers, a first laser spot size, and a second laser spot size; the dual laser collaborative scanning mode includes a follow-up mode and a parallel mode; According to 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 areas of the metal parts to be manufactured based on the grain and part performance database; Carry out layered slicing on the metal parts to be manufactured to obtain slicing files; 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 parts to be manufactured according to the process database, and form a printing file; The printing file is imported into the dual laser same-format printing device to manufacture the metal parts to be manufactured.

2. The method for three-dimensional manufacturing of metal grains based on dual laser powder bed fusion according to claim 1, characterized in that: The process database of establishing dual laser printing parameters and corresponding metal grains is specifically as follows: According to the single laser printing process of the prepared material, different combinations of dual laser printing parameters are designed, and test samples are printed by dual laser powder bed fusion additive manufacturing equipment; The test samples were metallographically prepared and the grain morphology was obtained by electron backscatter diffraction; The corresponding grain morphologies under different dual laser printing parameters are associated to obtain a process database of dual laser printing parameters and corresponding metal grains.

3. The method for three-dimensional manufacturing of metal grains based on dual laser powder bed fusion according to claim 1, characterized in that: The following mode refers to a working mode in which the second laser beam follows the printing path of the first laser beam to print within the dual laser start time interval. The relationship between the dual laser printing parameters and the growth of metal grains in the following mode is: (1) When the second laser power is greater than or equal to the first laser power, or the dual laser start-up time interval is within the first set time interval range, the remelting molten pool formed by the second laser beam is deeper than the forming molten pool formed by the first laser beam, and the metal grains continue to grow with the previous layer of molten pool grains as the solidification front and nucleation point, forming coarse and continuous metal grains; (2) When the second laser power is equal to the first laser power * the set percentage, or when the dual laser start time interval is outside the first set time interval range and within the second set time interval range, the remelting pool formed by the second laser beam is shallower than the boundary of the forming pool formed by the first laser beam, and the metal grains grow upward again along the bottom of the forming pool, obtaining metal grains with uniform directionality and texture orientation and smaller size; The parallel mode refers to a working mode in which the first laser beam and the second laser beam print in 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 parallel mode is: When the sum of the squares of the X-direction spacing between the dual lasers and the Y-direction spacing between the dual 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 at the same time: if the dual laser spacing is within the set spacing range, the same molten pool produces metal grains with more continuous vertical growth, stronger texture, and larger vertical size; if the dual laser spacing is outside the set spacing range, the same molten pool solidifies to produce metal grains with stronger integrity and larger lateral size.

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

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

6. The method for three-dimensional manufacturing of metal grains based on dual laser powder bed fusion according to claim 1, characterized in that: The slicing file is formed by segmenting different regions of the metal part to be manufactured using slicing software.

7. The method for three-dimensional manufacturing of metal grains based on dual laser powder bed fusion according to claim 1, characterized in that: The manufacturing of the metal parts to be manufactured is specifically as follows: Import the printing file into the dual-laser same-format printing equipment, integrate the shape and performance of the metal parts, and set the dual-laser collaborative printing parameters 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 area of ​​each slice layer in the slice file; Printing starts until all slice layers are formed, and a metal part with a composite of multiple grain morphologies is obtained.

8. A metal grain three-dimensional manufacturing system based on dual laser powder bed fusion, characterized in that: The system includes a process database building module, a performance database building module, a grain feature acquisition module, a layered slicing module, a print file forming module and a manufacturing module; The process database building module is used to establish a process database of dual laser printing parameters and corresponding metal grains according to the growth relationship between dual laser printing parameters and metal grains; the dual laser printing parameters include dual laser collaborative scanning mode, dual laser start time interval, first laser power, second laser power, X-direction spacing between dual lasers, Y-direction spacing between dual lasers, first laser spot size and second laser spot size; the dual laser collaborative scanning mode includes a follow-up mode and a parallel mode; The performance database building module is used to establish a grain and part performance database based on the correspondence between the grain characteristics and the mechanical properties and corrosion resistance of the dual laser forming material; The grain feature acquisition module is used to obtain the performance requirements of the metal parts to be manufactured, and obtain the grain characteristics and distribution of different areas of the metal parts to be manufactured according to the grain and part performance database; The layered slicing module is used to perform layered slicing on the metal parts to be manufactured to obtain slicing files; The printing file forming 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 for different areas of the metal parts to be manufactured according to the process database, and form a printing file; The manufacturing module is used to import the printing file into the dual-laser same-format printing device to manufacture the metal parts to be manufactured.

9. An electronic device, characterized in that: The electronic device comprises: at least one processor; and a memory in communication with the at least one processor; wherein, The memory stores computer program instructions that can be executed by the at least one processor, and the computer program instructions are executed by the at least one processor so that the at least one processor can execute the three-dimensional manufacturing method of metal grains based on dual laser powder bed fusion as described in any one of claims 1-7.

10. A computer-readable storage medium storing a program, characterized in that: When the program is executed by a processor, the three-dimensional manufacturing method of metal grains based on dual laser powder bed melting as described in any one of claims 1 to 7 is implemented.

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