Method and equipment for regulating and controlling forming degree through multi-beam integrated in-light coaxial additive manufacturing

Abstract

The invention discloses a method and equipment for regulating and controlling the forming degree through multi-beam integrated in-light coaxial additive manufacturing, and the method comprises the steps: loading a wire disc to a wire feeder in advance, and guaranteeing that the wire is fed in a manner of being perpendicular to the surface of a substrate; creating a model, importing the model into slicing software, planning a forming path, and setting power, scanning speed, wire feeding speed and lifting amount of six paths of laser in the laser device on an industrial personal computer; the power of the six paths of lasers is adjusted to start printing, specifically, the first laser and the second laser in the six paths of lasers are coupled into a first laser source, the fourth laser and the fifth laser are coupled into a second laser source, the first laser source is adjusted to be high in power, the second laser source is adjusted to be low in power, and the power of the third laser and the power of the sixth laser are kept unchanged; and therefore, the convection backflow amount and direction in the molten pool are changed, the trend that liquid metal flows towards the side face is restrained, and the additive part stable in size and free of surface collapse is continuously deposited and printed.

Description

Technical Field

[0001] The present invention relates to the technical field of laser additive manufacturing, and in particular to a method and device for regulating the forming degree of coaxial additive manufacturing in multi-beam integrated light. Background Art

[0002] With the development of science and technology, additive manufacturing (3D printing) technology is increasingly being used in the manufacturing industry. Additive manufacturing technology can efficiently produce parts with complex shapes by depositing materials layer by layer, especially in the fields of aerospace, automobile transportation, and medical treatment. In metal additive manufacturing, laser fuse additive manufacturing technology has attracted widespread attention due to its high precision and high efficiency. This technology uses a laser beam to melt the wire material and deposit it layer by layer on the substrate to form the desired three-dimensional structure.

[0003] Existing laser fuse additive manufacturing technologies usually use a single laser beam or a few laser beams for melting and deposition. These technologies can achieve high-precision manufacturing to a certain extent, but often face some challenges during the deposition process. For example, the flow direction and speed of liquid metal in the molten pool are difficult to accurately control, which can easily cause the liquid metal to flow to both sides, affecting the forming quality. In addition, the use of a single laser beam or a few laser beams limits the fine control of the temperature gradient of the molten pool, thereby affecting the uniformity and stability of convection in the molten pool. These problems limit the application of additive manufacturing technology in the manufacture of complex structures and high-precision parts.

[0004] Existing additive manufacturing technologies have obvious deficiencies in controlling convection in the molten pool. Since the temperature gradient in the molten pool cannot be precisely controlled, the liquid metal tends to flow to both sides, resulting in reduced forming quality, rough surface, and low dimensional accuracy. In addition, the use of a single laser beam or a few laser beams also limits the uniform control of the molten pool temperature, which can easily lead to heat accumulation and grain growth, affecting the mechanical properties of the material. Summary of the invention

[0005] In view of the above defects or improvement needs of the prior art, the purpose of the present invention is to provide a method and equipment for regulating the forming degree in multi-beam integrated light coaxial additive manufacturing. The method independently regulates the power of each laser through a multi-beam integrated light coaxial wire feeding laser, so that the power of one side in the spot coupling is greater than the other side, and the temperature gradient is transformed, thereby changing the flow rate and direction of the convection in the molten pool, enhancing the Marangoni convection, and effectively suppressing the tendency of liquid metal to flow to the side, thereby improving the forming degree and surface quality. And by changing the laser power of different laser beams in the laser additive manufacturing process, the collapse of the molded parts in the continuous deposition forming process can be controlled, the forming degree of the components can be improved, and the integrated manufacturing of the structural parts without adding physical fields or active elements can be realized. It is simple to operate, convenient to use, and integrated forming is suitable for the improvement of additive manufacturing formed components.

[0006] According to one aspect of the present invention, a method for controlling the forming degree of coaxial additive manufacturing in multi-beam integrated light is provided, comprising:

[0007] S100, pre-install the wire reel to the wire feeder, ensure that the wire is perpendicular to the surface of the substrate, adjust the working distance between the coaxial wire feeding laser in the multi-beam integrated light and the substrate, and ensure that the defocus amount is within a specified range; the laser includes six lasers distributed in a ring shape and a guide nozzle arranged in the hollow area of ​​the ring;

[0008] S200, create a model and import it into the slicing software, plan the molding path, and set the scanning speed, wire feeding speed and lifting amount during printing on the industrial computer;

[0009] S300, printing components by adjusting the powers of the six lasers, wherein adjusting the powers of the six lasers includes coupling the first laser and the second laser in the six lasers into a first laser source, coupling the fourth laser and the fifth laser into a second laser source, adjusting the first laser source to high power, and the second laser source to low power, wherein the powers of the third laser and the sixth laser remain unchanged, thereby changing the amount and direction of convection reflux in the molten pool, inhibiting the tendency of liquid metal to flow to the side, and continuously depositing and printing additive parts with stable dimensions and no surface collapse.

[0010] Furthermore, it also includes coupling the first laser, the second laser and the third laser of the six lasers into a first laser source, and the fourth laser, the fifth laser and the sixth laser into a second laser source, adjusting the first laser source to high power and the second laser source to low power, thereby changing the amount and direction of convection reflux in the molten pool, inhibiting the tendency of liquid metal to flow to the side, and continuously depositing and printing additive parts with stable dimensions and no surface collapse.

[0011] Furthermore, the six lasers are fixed above the substrate, and the angles between each laser and the vertical direction are equal, so as to ensure that the laser heat source can be focused on the surface of the component.

[0012] Furthermore, the surface of the substrate needs to be polished in advance, and the surface needs to be wiped and dried with acetone or alcohol solution, and then the four corners of the substrate need to be fixed on a workbench filled with inert gas with a clamp.

[0013] Furthermore, step S100 also includes: opening the gas cylinder valve and the gas inlet of the additive equipment, and adjusting the flow rate of the shielding gas to prevent excessive flow rate from affecting the morphology of the molten pool.

[0014] Furthermore, the forming path in step S200 includes a cyclical type and a chessboard type.

[0015] Furthermore, the power, scanning speed, wire feeding speed and lifting amount of the six lasers in step S200 need to be kept consistent.

[0016] Furthermore, the component printing process in step S300 also includes controlling the laser power and wire feeding speed so that the wire forms a stable liquid bridge under the action of the laser beam, and obtaining a melt path with good size through the stable liquid bridge transition, thereby improving the stability of the molten pool and the forming quality.

[0017] According to a second aspect of the present invention, there is provided a device for controlling the forming degree of coaxial additive manufacturing in multi-beam integrated light, which is used to implement any step of the above-mentioned method for controlling the forming degree of coaxial additive manufacturing in multi-beam integrated light, including:

[0018] A substrate, used for carrying the parts to be printed;

[0019] A working platform disposed on the bottom side of the substrate, used to fix and drive the substrate to move along the scanning direction during printing;

[0020] A multi-beam integrated light coaxial wire feeding laser disposed on the top side of the substrate, the laser comprising: six lasers distributed in an annular pattern, the power of each laser being independently adjustable; and a guide nozzle disposed in the annular hollow region, for conveying the wire along the center line direction of the laser beam;

[0021] Industrial computer, used to control the entire additive manufacturing process, including receiving user instructions, performing calculations and logical judgments, and sending control signals;

[0022] The control module is connected to the industrial computer for controlling the power of each laser according to the instructions of the industrial computer, thereby changing the reflux amount and direction of convection in the molten pool, inhibiting the tendency of liquid metal to flow to the side, and improving the forming degree of the component.

[0023] Furthermore, it also includes a cooling system and a protective gas system. The cooling system includes a cooling fan and a coolant circulation device to prevent the printing area from overheating, and the protective gas system is used to provide inert gas protection to prevent oxidation.

[0024] Beneficial effects:

[0025] 1. This method uses a coaxial wire feeding laser in a multi-beam integrated light system to independently regulate the power of each laser, so that the power on one side of the spot coupling is greater than the other side, achieving a temperature gradient transition, thereby changing the flow rate and direction of convection in the molten pool. The Marangoni convection is enhanced, effectively suppressing the tendency of liquid metal to flow to the side, thereby improving the forming degree and surface quality.

[0026] 2. This method can control the collapse of molded parts in the continuous deposition forming process by changing the laser power of different laser beams during the laser additive manufacturing process, improve the forming degree of the components, and realize the integrated manufacturing of structural parts without adding physical fields or active elements. It is simple to operate, easy to use, and integrated forming, and is suitable for the improvement of additive manufacturing formed components.

[0027] Additional aspects and advantages of the present application will be partially given in the following description, which will become apparent from the following description, or will be understood through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0029] Figure 1 This is a schematic diagram of a multi-beam integrated light coaxial wire feeding laser in an embodiment of the present invention;

[0030] Figure 2 It is a flow chart of a method for controlling the forming degree in coaxial additive manufacturing in multi-beam integrated light according to an embodiment of the present invention;

[0031] Figure 3 It is a schematic diagram of a single laser beam acting on a molten pool according to an embodiment of the present invention;

[0032] Figure 4 It is a principle diagram of multiple laser beams acting on a molten pool according to an embodiment of the present invention;

[0033] In all the drawings, the same reference numerals represent the same technical features, specifically:

[0034] 1-first laser; 2-second laser; 3-third laser; 4-fourth laser; 5-fifth laser; 6-sixth laser; 7-guide nozzle; 8-substrate; 9-wire; 10-first laser source; 11-second laser source. DETAILED DESCRIPTION

[0035] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0036] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] Those skilled in the art will appreciate that, unless otherwise stated, the singular forms "a", "an", "said" and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present application refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0038] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as the general understanding of those skilled in the art to which this application belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and will not be interpreted with an idealized or overly formal meaning unless specifically defined as in the embodiments of this application.

[0039] The present invention provides a method and device for regulating the forming degree in multi-beam integrated light coaxial additive manufacturing. The method independently regulates the power of each laser through a multi-beam integrated light coaxial wire feeding laser, so that the power of one side in the spot coupling is greater than the other side, and the temperature gradient is changed, thereby changing the flow rate and direction of the convection in the molten pool, enhancing the Marangoni convection, and effectively suppressing the tendency of liquid metal to flow to the side, thereby improving the forming degree and surface quality. And by changing the laser power of different laser beams in the laser additive manufacturing process, the collapse of the molded parts in the continuous deposition forming process can be controlled, the forming degree of the components can be improved, and the integrated manufacturing of the structural parts without adding physical fields or active elements can be realized. The operation is simple, the use is convenient, and the integrated forming is suitable for the improvement of the additive manufacturing formed components.

[0040] Embodiment 1:

[0041] like Figure 1 Figure 4As shown, an embodiment of the present invention provides a device for regulating the forming degree of multi-beam integrated light coaxial additive manufacturing, comprising: a substrate 8 for carrying a part to be printed; a working platform provided on the bottom side of the substrate for fixing and driving the substrate to move along a scanning direction during printing; a multi-beam integrated light coaxial wire feeding laser provided on the top side of the substrate, such as Figure 1 As shown, the laser includes: a first laser 1, a second laser 2, a third laser 3, a fourth laser 4, a fifth laser 5, a sixth laser 6 distributed in an annular manner, and a guide nozzle 7 arranged in the annular hollow area, which is used to transport the wire along the center line direction of the laser beam; an industrial computer, which is used to control the entire additive manufacturing process, including receiving user instructions, executing calculations and logical judgments, and sending control signals; a control module, which is connected to the industrial computer for communication, and is used to adjust and output the power of each laser according to the instructions of the industrial computer, thereby changing the reflux amount and direction of convection in the molten pool, inhibiting the tendency of liquid metal to flow to the side, and improving the forming degree of the component.

[0042] Furthermore, it also includes a cooling system and a protective gas system. The cooling system includes a cooling fan and a coolant circulation device to prevent the printing area from overheating, and the protective gas system is used to provide inert gas protection to prevent oxidation.

[0043] Embodiment 2:

[0044] like Figure 1 Figure 2 Figure 4 As shown, an embodiment of the present invention provides a method for controlling the forming degree of coaxial additive manufacturing in multi-beam integrated light, comprising:

[0045] S100, pre-install the wire reel on the wire feeder, ensure that the wire is fed perpendicularly to the surface of the substrate, adjust the working distance between the coaxial wire feeding laser in the multi-beam integrated light and the substrate, and ensure that the defocus amount is within a specified range;

[0046] Among them, the diameter of the wire is between 0.8mm and 1.2mm. The surface of the substrate needs to be polished in advance, and the surface needs to be wiped and blown dry with acetone or alcohol solution, and then the four corners of the substrate need to be fixed on a workbench filled with inert gas with a clamp; it is also necessary to open the gas cylinder valve and the air inlet of the additive equipment, and adjust the flow rate of the protective gas to prevent excessive flow rate from affecting the morphology of the molten pool.

[0047] S200, creating a model and importing it into a slicing software, planning a molding path, and setting the power, scanning speed, wire feeding speed, and lifting amount of the six lasers in the laser on an industrial computer;

[0048] The forming paths include a circular reciprocating type and a chessboard type; the power, scanning speed, wire feeding speed and lifting amount of the six lasers must be kept consistent;

[0049] S300, according to the forming path and the power, scanning speed, wire feeding speed and lifting amount of the six lasers, single-wall printing is started by adjusting the power of the six lasers, including coupling the first laser 1 and the second laser 2 in the six lasers into a first laser source 10, coupling the fourth laser 4 and the fifth laser 5 into a second laser source 11, adjusting the first laser source 10 to high power, the second laser source 11 to low power, wherein the power of the third laser 3 and the sixth laser 6 remains unchanged, thereby changing the amount and direction of convection reflux in the molten pool, suppressing the tendency of liquid metal to flow to the side, and continuously depositing and printing additive parts with stable dimensions and no surface collapse.

[0050] The method of adjusting the power of the six lasers also includes coupling the first laser 1, the second laser 2 and the third laser 3 in the six lasers into a first laser source 10, and the fourth laser 4, the fifth laser 5 and the sixth laser 6 into a second laser source 11, adjusting the first laser source 10 to high power and the second laser source 11 to low power, thereby changing the amount and direction of convection reflux in the molten pool, inhibiting the tendency of liquid metal to flow to the side, and continuously depositing and printing additive parts with stable dimensions and no surface collapse.

[0051] Furthermore, the six lasers are fixed above the substrate 8, and the angles of each laser with the vertical direction are equal, so that the laser heat source can be focused on the surface of the component; the liquid bridge transition technology is adopted in the wire feeding process of the wire 9, and the laser power and the wire feeding speed are controlled so that the wire 9 forms a stable liquid bridge under the action of the laser beam, thereby ensuring a smooth transition between the wire 9 and the molten pool, thereby improving the stability of the molten pool and the forming quality.

[0052] Embodiment 3:

[0053] The embodiment of the present invention provides a method for controlling the forming degree of coaxial additive manufacturing in multi-beam integrated light, comprising:

[0054] S100, install a wire reel with a diameter of 1.0mm on the wire feeder, and ensure that the wire is fed perpendicular to the substrate. Open the gas cylinder valve and the air inlet of the additive equipment, and adjust the flow rate of the shielding gas to 15L / min to prevent excessive flow rate from affecting the morphology of the molten pool. Grind the surface of the substrate, wipe and dry the surface with an organic solvent (such as acetone and alcohol solution). After cleaning, fix the four corners of the substrate on the workbench with a clamp.

[0055] S200, adjust the working distance between the laser and the substrate to 15mm, and ensure that the defocus is within the specified range. Create a single-wall model, import it into the slicing software, plan the molding path as a reciprocating method, set the scanning speed to 1000mm / min, the wire feeding speed to 10m / min, and the lifting amount to 0.1mm.

[0056] S300. Before starting printing, the power output of each laser is adjusted by the control module. The specific settings are as follows: the first laser and the second laser of the six lasers are coupled as the first laser source, the fourth laser and the fifth laser are coupled as the second laser source, the first laser source is adjusted to high power, the second laser source is adjusted to low power, and the power of the third laser and the sixth laser remains unchanged. By adjusting the power ratio of each laser, the temperature gradient in the molten pool is changed, thereby controlling the flow rate and direction of the convection in the molten pool, and suppressing the tendency of the liquid metal to flow to the side.

[0057] During the printing process, the laser remains stationary, and the substrate platform moves along the scanning direction (SD) to deposit the wire layer by layer. After each layer is completed, the substrate platform moves a short distance along the deposition direction (DD) to start printing the next layer. By real-time monitoring and adjusting the laser power, the temperature and convection direction in the molten pool can be ensured to be always in the best state. After printing, the surface quality and dimensional accuracy of the single wall are evaluated. The results show that the surface of the single wall is smooth, the dimensional accuracy is high, and there is no obvious collapse and unevenness.

[0058] Embodiment 4:

[0059] The embodiment of the present invention provides a method for controlling the forming degree of coaxial additive manufacturing in multi-beam integrated light, comprising:

[0060] S100, install the wire reel with a diameter of 1.2mm to the wire feeder, and ensure that the wire is fed perpendicular to the substrate. Open the gas cylinder valve and the air inlet of the additive equipment, and adjust the flow rate of the shielding gas to 20L / min to prevent excessive flow rate from affecting the morphology of the molten pool. Grind the surface of the substrate, wipe and dry the surface with an organic solvent (such as acetone and alcohol solution). After cleaning, fix the four corners of the substrate on the workbench with a clamp.

[0061] S200, adjust the working distance between the laser and the substrate to 20mm, and ensure that the defocus is within the specified range. Create a single-wall model, import it into the slicing software, plan the forming path as a chessboard scanning path, set the scanning speed to 800mm / min, the wire feeding speed to 8m / min, and the lifting amount to 0.2mm.

[0062] S300, before starting printing, the power output of each laser is regulated by the control module. The specific settings are as follows: the first laser, the second laser and the third laser of the six lasers are coupled as the first laser source, the fourth laser, the fifth laser and the sixth laser are the second laser source, the second laser source is adjusted to high power, and the first laser source is adjusted to low power. By adjusting the power ratio of each laser, the temperature gradient in the molten pool is changed, thereby controlling the flow rate and direction of convection in the molten pool, and suppressing the tendency of liquid metal to flow to the side.

[0063] During the printing process, the laser remains stationary, and the substrate platform moves along the scanning direction (SD) and the deposition direction (DD) to deposit the wire layer by layer. After each layer is completed, the substrate platform moves a short distance in the deposition direction to start printing the next layer. By real-time monitoring and adjusting the laser power, the temperature and convection direction in the molten pool are always in the best state. After printing, the surface quality and dimensional accuracy of the single wall are evaluated. The results show that the surface of the complex structure is smooth, the dimensional accuracy is high, and there is no obvious collapse and unevenness.

[0064] Embodiment 5:

[0065] S100, install a wire reel with a diameter of 1.0mm on the wire feeder, and ensure that the wire is fed perpendicular to the substrate. Open the gas cylinder valve and the air inlet of the additive equipment, and adjust the flow rate of the shielding gas to 15L / min to prevent excessive flow rate from affecting the morphology of the molten pool. Grind the surface of the substrate, wipe and dry the surface with an organic solvent (such as acetone and alcohol solution). After cleaning, fix the four corners of the substrate on the workbench with a clamp.

[0066] S200, adjust the working distance between the laser and the substrate to 15mm, and ensure that the defocus is within the specified range. Create a single-wall model, import it into the slicing software, plan the molding path as a reciprocating method, set the scanning speed to 1000mm / min, the wire feeding speed to 10m / min, and the lifting amount to 0.1mm.

[0067] S300, before starting printing, the power output of each laser is regulated by the control module. The specific settings are as follows: the first laser, the second laser and the third laser of the six lasers are coupled as the first laser source, the fourth laser, the fifth laser and the sixth laser are the second laser source, the second laser source is adjusted to high power, and the first laser source is adjusted to low power. By adjusting the power ratio of each laser, the temperature gradient in the molten pool is changed, thereby controlling the flow rate and direction of convection in the molten pool, and suppressing the tendency of liquid metal to flow to the side.

[0068] Among them, when starting the printing, the laser remains fixed, and the substrate platform moves along the scanning direction (SD) to deposit the wire layer by layer. After each layer is completed, the substrate platform moves a short distance along the deposition direction (DD) to start printing the next layer. By real-time monitoring and adjusting the laser power, the temperature and convection direction in the molten pool are always in the best state. After the printing is completed, the surface quality and dimensional accuracy of the single wall are evaluated. The results show that the surface of the single wall is smooth, the dimensional accuracy is high, and there is no obvious collapse and unevenness.

[0069] Embodiment 6:

[0070] The embodiment of the present invention provides a method for controlling the forming degree of coaxial additive manufacturing in multi-beam integrated light, comprising:

[0071] S100, install the wire reel with a diameter of 1.2mm to the wire feeder, and ensure that the wire is fed perpendicular to the substrate. Open the gas cylinder valve and the air inlet of the additive equipment, and adjust the flow rate of the shielding gas to 20L / min to prevent excessive flow rate from affecting the morphology of the molten pool. Grind the surface of the substrate, wipe and dry the surface with an organic solvent (such as acetone and alcohol solution). After cleaning, fix the four corners of the substrate on the workbench with a clamp.

[0072] S200, adjust the working distance between the laser and the substrate to 20mm, and ensure that the defocus is within the specified range. Create a single-wall model, import it into the slicing software, plan the forming path as a chessboard scanning path, set the scanning speed to 800mm / min, the wire feeding speed to 8m / min, and the lifting amount to 0.2mm.

[0073] S300. Before starting printing, the power output of each laser is adjusted by the control module. The specific settings are as follows: the first laser and the second laser of the six lasers are coupled as the first laser source, the fourth laser and the fifth laser are coupled as the second laser source, the first laser source is adjusted to high power, the second laser source is adjusted to low power, and the power of the third laser and the sixth laser remains unchanged. By adjusting the power ratio of each laser, the temperature gradient in the molten pool is changed, thereby controlling the flow rate and direction of the convection in the molten pool, and suppressing the tendency of the liquid metal to flow to the side.

[0074] During the printing process, the laser remains stationary, and the substrate platform moves along the scanning direction (SD) and the deposition direction (DD) to deposit the wire layer by layer. After each layer is completed, the substrate platform moves a short distance in the deposition direction to start printing the next layer. By real-time monitoring and adjusting the laser power, the temperature and convection direction in the molten pool are always in the best state. After printing, the surface quality and dimensional accuracy of the single wall are evaluated. The results show that the surface of the complex structure is smooth, the dimensional accuracy is high, and there is no obvious collapse and unevenness.

[0075] like Figure 3 As shown in the figure, the behavior of the molten pool under a single laser beam is mainly affected by four forces: buoyancy (caused by the density difference of liquid metal in space), Marangoni force (caused by the difference in surface tension gradient of liquid metal), gravity and gas flow shear force (caused by the high-speed eruption of metal vapor generated by laser heating or plasma induced by laser). Although there are differences in composition inside the molten pool, its effect on density is minimal and is generally ignored when analyzing buoyancy. At the same time, a large number of studies have shown that Marangoni force dominates the molten pool formed in the heat conduction mode. When the laser heats the substrate surface, the highest temperature is located in the center of the molten pool and decreases in the radial direction, which leads to differences in surface tension in different areas of the molten pool. At this time, the direction of the Marangoni force is from the center of the molten pool to the edge of the molten pool, causing the melt in the molten pool to flow outward.

[0076] Among them, temperature gradient is considered to be the main driving force for melt flow during laser melting of pure metals and most alloys. Changing the temperature gradient in the molten pool can change the flow rate and direction of convection in the molten pool. The amount of reflux mainly depends on the highest heating temperature of the center surface of the molten pool spot. The higher the surface temperature of the center of the molten pool spot, the greater the surface tension gradient of the molten pool, and the greater the reflux of the melt.

[0077] like Figure 4 As shown, by controlling the power of the multi-beam laser, the power on one side of the spot coupling can be made greater than the power on the other side, thereby realizing the transformation of the temperature gradient, causing the internal convection in the molten pool to be changed to external convection, enhancing the Marangoni convection, promoting the flow of the melt, and making the temperature of the molten pool more uniform.

[0078] It should be understood that, although the steps in the flowchart of the accompanying drawings are displayed in sequence as indicated by the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least a part of the steps in the flowchart of the accompanying drawings may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be executed in turn or alternately with other steps or at least a part of the sub-steps or stages of other steps.

[0079] The above description is only a partial implementation method of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for controlling the forming degree of coaxial additive manufacturing in multi-beam integrated light, characterized in that: include: S100, pre-install the wire reel to the wire feeder, ensure that the wire is perpendicular to the surface of the substrate, adjust the working distance between the coaxial wire feeding laser in the multi-beam integrated light and the substrate, and ensure that the defocus amount is within a specified range; the laser includes six lasers distributed in a ring shape and a guide nozzle arranged in the hollow area of ​​the ring; S200, create a model and import it into the slicing software, plan the molding path, and set the scanning speed, wire feeding speed and lifting amount during printing on the industrial computer; S300, printing components by adjusting the powers of the six lasers, wherein adjusting the powers of the six lasers includes coupling the first laser and the second laser in the six lasers into a first laser source, coupling the fourth laser and the fifth laser into a second laser source, adjusting the first laser source to high power, and the second laser source to low power, wherein the powers of the third laser and the sixth laser remain unchanged, thereby changing the amount and direction of convection reflux in the molten pool, inhibiting the tendency of liquid metal to flow to the side, and continuously depositing and printing additive parts with stable dimensions and no surface collapse.

2. The method for controlling the forming degree of coaxial additive manufacturing in multi-beam integrated light according to claim 1, characterized in that: The method also includes coupling the first laser, the second laser and the third laser of the six lasers into a first laser source, and the fourth laser, the fifth laser and the sixth laser into a second laser source, and adjusting the first laser source to high power and the second laser source to low power, so as to change the amount and direction of convection reflux in the molten pool, inhibit the tendency of liquid metal to flow to the side, and continuously deposit and print additive parts with stable dimensions and no surface collapse.

3. The method for controlling the forming degree of coaxial additive manufacturing in multi-beam integrated light according to claim 2, characterized in that: The six lasers are fixed above the substrate, and the angles between each laser and the vertical direction are equal, so as to ensure that the laser heat source can be focused on the surface of the component.

4. The method for controlling the forming degree of coaxial additive manufacturing in multi-beam integrated light according to claim 3, characterized in that: The surface of the substrate needs to be polished in advance, and the surface is wiped and dried with acetone or alcohol solution, and then the four corners of the substrate are fixed on a workbench filled with inert gas with a clamp.

5. The method for controlling the forming degree of coaxial additive manufacturing in multi-beam integrated light according to claim 1, characterized in that: Step S100 also includes: opening the gas cylinder valve and the gas inlet of the additive equipment, and adjusting the flow rate of the shielding gas to prevent excessive flow rate from affecting the morphology of the molten pool.

6. The method for controlling the forming degree of coaxial additive manufacturing in multi-beam integrated light according to any one of claims 1 to 5, characterized in that: The forming paths in step S200 include a cyclical type and a chessboard type.

7. The method for controlling the forming degree of multi-beam integrated light coaxial additive manufacturing according to any one of claims 1 to 5, characterized in that: The power, scanning speed, wire feeding speed and lifting amount of the six lasers in step S200 must be kept consistent.

8. The method for controlling the forming degree of coaxial additive manufacturing in multi-beam integrated light according to claim 1, characterized in that: The component printing process in step S300 also includes controlling the laser power and wire feeding speed so that the wire forms a stable liquid bridge under the action of the laser beam, and obtaining a melt path with good size through the stable liquid bridge transition, thereby improving the stability of the molten pool and the forming quality.

9. A device for controlling the forming degree of multi-beam integrated light coaxial additive manufacturing, used to implement a method for controlling the forming degree of multi-beam integrated light coaxial additive manufacturing according to any one of claims 1 to 7, characterized in that: include: A substrate, used for carrying the parts to be printed; A working platform disposed on the bottom side of the substrate, used to fix and drive the substrate to move along the scanning direction during printing; A multi-beam integrated light coaxial wire feeding laser disposed on the top side of the substrate, the laser comprising: six lasers distributed in an annular pattern, the power of each laser being independently adjustable; and a guide nozzle disposed in the annular hollow region, for conveying the wire along the center line direction of the laser beam; Industrial computer, used to control the entire additive manufacturing process, including receiving user instructions, performing calculations and logical judgments, and sending control signals; The control module is connected to the industrial computer for controlling the power of each laser according to the instructions of the industrial computer, thereby changing the reflux amount and direction of convection in the molten pool, inhibiting the tendency of liquid metal to flow to the side, and improving the forming degree of the component.

10. The device for controlling the forming degree of multi-beam integrated light coaxial additive manufacturing according to claim 9, characterized in that: It also includes a cooling system and a protective gas system. The cooling system includes a cooling fan and a coolant circulation device to prevent the printing area from overheating, and the protective gas system is used to provide inert gas protection to prevent oxidation.

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