A multi-material laser additive forming process and laser oscillation forming system

Abstract

The present invention provides a multi-material laser additive forming process and a laser oscillation forming system, belonging to the field of laser processing technology, including step S1: forming a multi-material L-PBF forming process database by training multiple multi-material forming components; S2: calling the multi-material L-PBF forming process database, intelligently segmenting the current component, and planning the powder laying process and laser oscillation forming process for each segmented part, wherein the powder laying process lays multi-material powder layer by layer according to preset requirements and controls the thickness of the powder layer; the laser oscillation forming process stirs the multi-material molten pool and shapes the laser beam through laser oscillation; S3: forming a multi-material component according to the powder laying process and laser oscillation forming process in step S1, and combining a powder laying device and a laser oscillation forming system. The present invention improves the quality of the formed product by using the powder laying process and laser oscillation forming process, and combining a powder laying device and a laser oscillation forming system.

Description

Technical Field

[0001] The present invention belongs to the field of laser processing technology and relates to a forming process, in particular to a multi-material laser additive forming process and a laser oscillation forming system. Background Art

[0002] Multi-material components integrating "material, structure, and performance" are a key trend in the manufacturing industry. Existing technologies utilize traditional techniques such as casting, forging, and machining to produce multi-material components. These processes are complex and cumbersome, with long processing cycles and high costs, making the production of complex multi-material components impossible. Multi-material laser powder bed fusion (L-PBF) technology, through the layer-by-layer, targeted laying of multi-material powders combined with a selective laser forming process, can produce high-precision, complex multi-material components with short processing cycles and high build quality. It is currently a key development direction in the field of laser additive manufacturing.

[0003] However, the existing multi-material L-PBF forming process of heterogeneous cross-sections has the following main shortcomings or deficiencies:

[0004] First, during the L-PBF forming process, the thermal physical properties of the parent materials of multi-material components vary, such as thermal expansion coefficient and melting point. During L-PBF forming, defects such as poor fusion, holes, and cracks often occur at the interface.

[0005] Second, during the L-PBF forming process, coarse brittle intermetallic compounds often precipitate at the multi-material interface. As the thermal stress of L-PBF forming continues to increase, macroscopic cracks will appear at the multi-material interface. Summary of the Invention

[0006] The purpose of the present invention is to address the above-mentioned problems in the existing technology and to propose a multi-material laser additive manufacturing process that can improve the quality of laser printing.

[0007] The object of the present invention can be achieved by the following technical solutions: A multi-material laser additive forming process, comprising:

[0008] S1: Form a multi-material L-PBF forming process database by training multiple multi-material forming components;

[0009] S2: Call the multi-material L-PBF forming process database to intelligently segment the current component and plan the powder laying process and laser oscillation forming process for each segmented part. The powder laying process lays multi-material powder layer by layer according to preset requirements and controls the thickness of the multi-material powder layer. The laser oscillation forming process stirs the multi-material molten pool through laser oscillation and shapes the laser beam.

[0010] S3: According to the powder spreading process and laser oscillation forming process in step S1, and in combination with the powder spreading device and the laser oscillation forming system, a multi-material component is formed.

[0011] In the above-mentioned multi-material laser additive forming process, the laser oscillation forming process in step S2 includes the following steps:

[0012] S21: dividing the forming component model of the current multi-material powder layer into an edge region and a filling region, wherein, when the forming component model of the current multi-material powder layer is arranged in a polygonal configuration, the edge region is located at the outer contour edge of the polygon; when the forming component model of the current multi-material powder layer is arranged in a pipe configuration, the edge region is located at the inner contour edge of the pipe;

[0013] S22: The edge area of ​​the component model is processed by a point light source, and the filling area of ​​the component model is processed by a surface light source formed by laser oscillation, thereby completing the processing of the component model in the current multi-material powder layer.

[0014] In the above-mentioned multi-material laser additive forming process, step S2 also includes step S23: using high-power laser high-frequency oscillation to form a uniform surface light source, and heat-treating the current multi-material powder layer to eliminate stress concentration or prevent local stress concentration. When the current multi-material powder layer needs to be preheated over a large area, step S23 is located before step S21; when the laser forming area needs to be locally subjected to high-temperature heat treatment, step S23 is performed simultaneously with step S22; when the stress concentration-prone area of ​​the formed component model needs to be heat-treated, step S23 is located after step S22.

[0015] The multi-material laser additive forming process further includes step S4: real-time online monitoring of the formed component. If defects occur in the current multi-material powder layer formed component model, the current formed component model is laser oscillated and remelted.

[0016] In the above-mentioned multi-material laser additive manufacturing process, step S4 includes the following steps:

[0017] S41: The laser beam remelts and scans the defective target area of ​​the current forming layer along a preset path in a high-frequency oscillation manner, so that the surface of the target area is melted and the forming defect is repaired;

[0018] S42: After step S41 is completed, the forming layer is analyzed again through online monitoring to detect whether the defect has been repaired. If not, return to step S41; if repaired, continue to step S2.

[0019] The above-mentioned multi-material laser additive manufacturing process further includes the following steps:

[0020] S5: Optimize and adjust the process online, and feed the adjusted parameter data back to the multi-material L-PBF forming process database to update the parameter data in the multi-material L-PBF forming process database.

[0021] The above-mentioned multi-material laser additive manufacturing process further includes the following steps:

[0022] S6: After the component is formed, the quality of the formed component is inspected.

[0023] In order to achieve the laser oscillation effect mentioned in steps S1-S6, the present invention also provides a laser oscillation forming system adopting the multi-material laser additive forming process, including a galvanometer assembly and a CNC machine tool, wherein the laser oscillation stirs the multi-material molten pool during the multi-material L-PBF forming process by adjusting the motion trajectory of the CNC machine tool in the X-axis and Y-axis directions; and the laser spot size is dynamically controlled by adjusting the distance of the CNC machine tool in the Z-axis direction.

[0024] In the above-mentioned laser oscillation forming system, the laser oscillation forming system includes:

[0025] A CNC machine tool, comprising a first output shaft movable along an X-axis, a second output shaft movable along a Y-axis, and a third output shaft movable along a Z-axis, wherein the first, second, and third output shafts form a three-coordinate system in space, and a galvanometer assembly provided with a laser light source is connected to the third output shaft;

[0026] The powder bed is located below the galvanometer assembly and is provided with a multi-material powder layer. The laser light source on the galvanometer assembly realizes laser printing of the multi-material powder layer along a preset trajectory.

[0027] In order to achieve the laser oscillation effect mentioned in steps S1-S6, the present invention also provides a laser oscillation forming system adopting the multi-material laser additive forming process, including an ultrasonic driver and a beam expander assembly and a galvanometer assembly in the optical path system, wherein the galvanometer assembly is driven by the ultrasonic driver to realize the stirring of the multi-material molten pool by laser oscillation during the multi-material L-PBF forming process; and the optical path beam expander assembly is driven by the ultrasonic driver to realize dynamic control of the laser spot size.

[0028] In the above-mentioned laser oscillation forming system, the laser oscillation forming system includes:

[0029] A beam expander assembly, other components in the optical path system, and a galvanometer assembly provided with a laser light source; and two ultrasonic drivers, namely a first ultrasonic driver and a second ultrasonic driver, wherein the first ultrasonic driver is connected to the beam expander assembly, and the second ultrasonic driver is connected to the galvanometer assembly;

[0030] The powder bed is located below the galvanometer assembly and is provided with a multi-material powder layer. The laser light source on the galvanometer assembly realizes laser printing of the multi-material powder layer along a preset trajectory.

[0031] In order to achieve the laser oscillation effect mentioned in steps S1-S6, the present invention also provides a laser oscillation forming system adopting the multi-material laser additive forming process, including a beam expander assembly, a galvanometer assembly and a rotating mirror assembly in the optical path system, wherein the galvanometer assembly is used to realize the scanning of the laser in the X-axis and Y-axis directions; the rotating mirror assembly is used to realize the stirring of the multi-material molten pool by laser oscillation during the multi-material L-PBF forming process, and to realize the dynamic control of the laser spot size.

[0032] In the above-mentioned laser oscillation forming system, the laser oscillation forming system includes:

[0033] Beam expander assembly, other components in the optical path system, galvanometer assembly, and rotating mirror assembly equipped with a laser light source;

[0034] The powder bed is located below the rotating mirror assembly and is provided with a multi-material powder layer. The laser light source on the rotating mirror assembly realizes laser printing of the multi-material powder layer along a preset trajectory.

[0035] In order to achieve the laser oscillation effect mentioned in steps S1-S6, the present invention also provides a laser oscillation forming system adopting the multi-material laser additive forming process, including an optical path system and a spatial light modulator, wherein the laser is positioned and the scanning path is planned by the spatial light modulator, so that the laser oscillation stirs the multi-material molten pool during the multi-material L-PBF forming process, and the laser spot size is dynamically controlled.

[0036] In the above-mentioned laser oscillation forming system, the laser oscillation forming system includes:

[0037] Other devices in the optical path system and a spatial light modulator equipped with a laser light source;

[0038] The powder bed is located below the spatial light modulator and has a multi-material powder layer laid on the powder bed. The laser light source on the spatial light modulator realizes laser printing of the multi-material powder layer along a preset trajectory.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] (1) The present invention provides a material laser additive forming process, which improves the quality of the formed product by using a powder spreading process and a laser oscillation forming process, and combining a powder spreading device and a laser oscillation forming system;

[0041] (2) Using laser oscillation to stir the multi-material interface molten pool, on the one hand, it can enhance the solution convection stirring effect, effectively capture bubbles in the molten pool, accelerate the escape of bubbles, and reduce the formation defects such as poor fusion of multi-material interfaces, holes, and cracks. On the other hand, it can effectively change the molten pool morphology, regulate the molten pool temperature field distribution, flow field convection, etc., and promote solution mixing and element diffusion, reducing the precipitation of coarse brittle intermetallic compounds;

[0042] (3) During the beam shaping process, a conventional small-diameter, high-precision point light source is used to print the edge of the formed component, so that the formed component can obtain a more uniform and fine structure, improve the strength, wear resistance and corrosion resistance of the surface of the formed component, and use a surface light source with high-speed laser oscillation scanning to improve the forming efficiency of the formed component, obtain a relatively coarse structure, and improve the overall plasticity and toughness of the formed component;

[0043] (4) Use high-power laser high-frequency oscillation to form a uniform surface light source to eliminate stress concentration or prevent local stress concentration;

[0044] (5) Through laser oscillation remelting, the forming defects of components are reduced, and the forming ability of structural features such as variability (such as thin-walled components), no support (such as cantilever components), and stress concentration (such as sharp-angle components) is greatly improved;

[0045] (6) Using high-power laser high-frequency oscillation to form a uniform surface light source to preheat the powder bed and components during the forming process can effectively expand the range of L-PBF processable materials, such as brittle materials such as refractory alloys and intermetallic compounds. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is a flow chart of a multi-material laser additive forming process of the present invention.

[0047] Figure 2 It is a structural schematic diagram of a laser oscillation forming system in Example 1 of the present invention.

[0048] Figure 3 It is a structural diagram of a laser oscillation forming system in the second embodiment of the present invention.

[0049] Figure 4 It is a structural schematic diagram of a laser oscillation forming system in embodiment three of the present invention.

[0050] Figure 5 It is a structural schematic diagram of a laser oscillation forming system in embodiment 4 of the present invention.

[0051] Figure 6 This is a diagram of the working principle of a surface light source in a multi-material laser additive forming process of the present invention.

[0052] Figure 7 It is a schematic diagram of processing a polygonal formed component model in a multi-material laser additive forming process of the present invention.

[0053] Figure 8 It is a schematic diagram of processing a formed component model in the form of a pipeline in a multi-material laser additive forming process of the present invention.

[0054] Figure 9 It is a structural schematic diagram of layer-by-layer processing in a multi-material laser additive forming process of the present invention.

[0055] In the figure,

[0056] 10. CNC machine tool; 11. First output shaft; 12. Second output shaft; 13. Third output shaft;

[0057] 20. Galvanometer assembly;

[0058] 30. Powder bed;

[0059] 40. Beam expander assembly;

[0060] 50. Other components in the optical system;

[0061] 60. Ultrasonic driver; 61. First ultrasonic driver; 62. Second ultrasonic driver;

[0062] 70. Rotating mirror assembly;

[0063] 80. Spatial light modulator;

[0064] S1, first optical path; S2, second optical path; S3, third optical path;

[0065] A1, edge area; A2, filling area;

[0066] B1, point light source; B2, surface light source. DETAILED DESCRIPTION

[0067] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0068] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0069] like Figures 1 to 9 As shown, the present invention provides a multi-material laser additive forming process, comprising the steps of:

[0070] S1: Form a multi-material L-PBF forming process database by training multiple multi-material forming components;

[0071] S2: Call the multi-material L-PBF forming process database to intelligently segment the current component and plan the powder laying process and laser oscillation forming process for each segmented part. The powder laying process lays multi-material powder layer by layer according to preset requirements and controls the thickness of the multi-material powder layer. The laser oscillation forming process stirs the multi-material molten pool through laser oscillation and shapes the laser beam.

[0072] S3: According to the powder spreading process and laser oscillation forming process in step S1, and in combination with the powder spreading device and the laser oscillation forming system, a multi-material component is formed.

[0073] The present invention provides a material laser additive forming process, which improves the quality of the formed product through a powder spreading process and a laser oscillation forming process, and combines a powder spreading device and a laser oscillation forming system.

[0074] It is further pointed out that the laser oscillation forming system in step S2 generally includes the following four implementation methods.

[0075] Method 1: Combine the galvanometer assembly 20 with a precision CNC machine tool 10 or a robotic arm. By adjusting the motion trajectory of the CNC machine tool 10 in the X-axis and Y-axis directions, the laser oscillation stirs the multi-material molten pool during the multi-material L-PBF forming process, and adjusts the oscillation path, frequency, amplitude and other parameters; by adjusting the distance of the CNC machine tool 10 in the Z-axis direction, the laser spot size can be dynamically controlled.

[0076] Method 2: Combining the ultrasonic driver 60 with the beam expander assembly 40 and the galvanometer assembly 20 in the optical path system, wherein the galvanometer assembly 20 is driven by the ultrasonic driver 60 to realize the stirring of the multi-material molten pool by laser oscillation during the multi-material L-PBF forming process, and adjust the oscillation path, frequency, amplitude and other parameters; and driving the optical path beam expander assembly 40 by the ultrasonic driver 60 to realize dynamic control of the laser spot size.

[0077] Method three is to combine the beam expander assembly 40, the galvanometer assembly 20 and the rotating mirror assembly 70 in the optical path system, wherein the galvanometer assembly 20 is used to realize fast and precise scanning of the laser in the X-axis and Y-axis directions; the rotating mirror assembly 70 is used to realize the stirring of the multi-material molten pool by laser oscillation during the multi-material L-PBF forming process, and adjust the oscillation path, frequency, amplitude and other parameters, and realize dynamic control of the laser spot size.

[0078] Method four is to combine the optical path system with the spatial light modulator 80, wherein the spatial light modulator 80 is used to accurately position the laser and plan the scanning path, so as to realize the stirring of the multi-material molten pool by the laser oscillation during the multi-material L-PBF forming process, adjust the oscillation path, frequency, amplitude and other parameters, and realize dynamic control of the laser spot size.

[0079] It is further pointed out that for method 1, the specific structure is as follows Figure 1 As shown, the laser oscillation forming system includes:

[0080] A CNC machine tool 10 is provided with a first output shaft 11 movable along the X-axis, a second output shaft 12 movable along the Y-axis, and a third output shaft 13 movable along the Z-axis. The first output shaft 11, the second output shaft 12, and the third output shaft 13 form a three-coordinate system in space, and a galvanometer assembly 20 provided with a laser light source is connected to the third output shaft 13.

[0081] The powder bed 30 is located below the galvanometer assembly 20 and a multi-material powder layer is laid on the powder bed 30 , wherein the laser light source on the galvanometer assembly 20 realizes laser printing of the multi-material powder layer along a preset trajectory.

[0082] It is further pointed out that for the second method, the specific structure is as follows Figure 2 As shown, the laser oscillation forming system includes:

[0083] The beam expander assembly 40, other devices 50 in the optical path system, and the galvanometer assembly 20 provided with a laser light source form a right triangle layout. The beam expander assembly 40 and the other devices 50 in the optical path system are connected via a first optical path S1, and the other devices 50 in the optical path system are connected to the galvanometer assembly 20 via a second optical path S2. The first optical path S1 and the second optical path S2 serve as two right-angled sides of the right triangle respectively.

[0084] Two ultrasonic drivers 60, namely a first ultrasonic driver 61 and a second ultrasonic driver 62, wherein the first ultrasonic driver 61 is connected to the beam expander assembly 40, and the second ultrasonic driver 62 is connected to the galvanometer assembly 20;

[0085] The powder bed 30 is located below the galvanometer assembly 20 and a multi-material powder layer is laid on the powder bed 30 , wherein the laser light source on the galvanometer assembly 20 realizes laser printing of the multi-material powder layer along a preset trajectory.

[0086] It is further pointed out that for the third method, the specific structure is as follows Figure 3 As shown, the laser oscillation forming system includes:

[0087] The beam expander assembly 40, other devices 50 in the optical path system, the galvanometer assembly 20, and the rotating mirror assembly 70 provided with a laser light source, and the four form a right-angled triangle layout, wherein the beam expander assembly 40 and the other devices 50 in the optical path system are connected via a first optical path S1, the other devices 50 in the optical path system are connected to the galvanometer assembly 20 via a second optical path S2, and the galvanometer assembly 20 and the rotating mirror assembly 70 are connected via a third optical path S3, and the first optical path S1 is located on one right-angled side of the right triangle, and the second optical path S2 and the third optical path S3 are located on the other right-angled side of the right triangle, or the first optical path S1 and the second optical path S2 are located on one right-angled side of the right triangle, and the third optical path S3 is located on the other right-angled side of the right triangle;

[0088] The powder bed 30 is located below the rotating mirror assembly 70 , and a multi-material powder layer is laid on the powder bed 30 , wherein the laser light source on the rotating mirror assembly 70 realizes laser printing of the multi-material powder layer along a preset trajectory.

[0089] It is further pointed out that for method 4, the specific structure is as follows Figure 4 As shown, the laser oscillation forming system includes:

[0090] The other components 50 in the optical path system and the spatial light modulator 80 provided with a laser light source are located on the same straight line, and the other components 50 in the optical path system and the spatial light modulator 80 are connected via a first optical path S1;

[0091] The powder bed 30 is located below the spatial light modulator 80 , and a multi-material powder layer is laid on the powder bed 30 , wherein the laser light source on the spatial light modulator 80 realizes laser printing of the multi-material powder layer along a preset trajectory.

[0092] It is worth mentioning that in this embodiment, the galvanometer assembly 20 generally includes one or more high-speed, high-precision mirrors mounted on a small motor (i.e., the galvanometer). By controlling the angle of the motor, the direction of the incident laser can be quickly and accurately changed.

[0093] The beam expander assembly 40 is primarily used to change the diameter and divergence angle of the laser beam. It typically consists of a set of lenses, and the distance between the lenses can be adjusted to magnify or reduce the size of the laser beam. The beam expander's primary function is to improve the quality of the laser beam, reduce the focused spot size, and minimize the divergence of the laser beam, thereby enhancing the efficiency and accuracy of laser processing or transmission.

[0094] Rotating mirror assembly 70 is a mirror that rotates around a specific axis, allowing it to continuously change the direction of a light beam. This assembly is often used in applications that require sweeping a beam across a specific angle, such as certain types of laser radar (LiDAR), barcode scanners, or specialized optical experimental setups. By rotating the assembly, the laser beam can cover a wider area, making it suitable for detecting or scanning targets over large areas.

[0095] A spatial light modulator 80 is a device that modulates the amplitude, phase, or polarization state of incident light in a spatially distributed manner. It is widely used in fields such as optical information processing, laser display, holography, wavefront correction, and quantum computing. The core function of a spatial light modulator 80 is to convert electrical signals into spatially distributed optical signals, thereby achieving precise control of the light beam.

[0096] In this embodiment, laser oscillation is used to stir the multi-material interface molten pool. On the one hand, it can enhance the solution convection stirring effect, effectively capture bubbles in the molten pool, accelerate the escape of bubbles, and reduce forming defects such as poor multi-material interface fusion, holes, and cracks. On the other hand, it can effectively change the molten pool morphology, regulate the molten pool temperature field distribution, flow field convection, etc., and promote solution mixing and element diffusion, thereby reducing the precipitation of coarse brittle intermetallic compounds.

[0097] Preferably, when the laser light source realizes laser printing of a multi-material powder layer of a component along a preset trajectory, the formed component model of the current multi-material powder layer can be divided into an edge area A1 and a filling area A2, wherein the edge area A1 is laser printed by a small-diameter, high-precision point light source B1, and the filling area A2 is laser reciprocatingly printed by a surface light source B2 formed by high-speed oscillation scanning.

[0098] In this embodiment, during the beam shaping process, a conventional small-diameter, high-precision point light source B1 is used to print the edge of the formed component, so that the formed component can obtain a more uniform and fine structure, thereby improving the strength, wear resistance and corrosion resistance of the surface of the formed component. The use of a surface light source B2 with high-speed laser oscillation scanning can improve the forming efficiency of the formed component, obtain a relatively coarse structure, and improve the overall plasticity and toughness of the formed component.

[0099] It is worth mentioning that Figure 5 As shown, when the forming component model of the current multi-material powder layer is set in a polygonal shape, the forming component model is first divided into an edge area A1 and a filling area A2, wherein the edge area A1 is located at the outer contour edge of the polygon, and then the edge area A1 is processed by the point light source B1, and the filling area A2 is processed by the surface light source B2 formed by laser oscillation, finally forming the forming component model required to be processed by the current multi-material powder layer.

[0100] like Figure 6As shown, when the forming component model of the current multi-material powder layer is set as a pipeline, the forming component model is first divided into an edge area A1 and a filling area A2, wherein the edge area A1 is located at the inner contour edge of the pipeline, and then the edge area A1 is processed by the point light source B1, and the filling area A2 is processed by the surface light source B2 formed by laser oscillation, and finally the forming component model required to be processed by the current multi-material powder layer is formed.

[0101] Preferably, when the laser light source realizes laser printing of a multi-material powder layer of a component along a preset trajectory, stress concentration may occur. In order to solve the stress concentration problem, the following three methods are generally adopted.

[0102] Method 1: Before the multi-material powder layer corresponding to the formed component model is formed, high-power laser high-frequency oscillation is used to form a uniform surface light source B2 to preheat the multi-material powder layer over a large area and adjust the stress distribution to prevent stress concentration.

[0103] Method 2: During the multi-material powder layer forming process corresponding to the formed component model, high-power laser high-frequency oscillation is used to form a uniform surface light source B2, and local high-temperature heat treatment is performed on the laser forming area to reduce the thermal stress during the forming process.

[0104] Method three: After the multi-material powder layer corresponding to the formed component model is formed, a high-power laser oscillates at a high frequency to form a uniform surface light source B2, and heat-treats the stress-concentration-prone areas of the formed component model to prevent local stress concentration.

[0105] Preferably, when the laser light source realizes laser printing of a multi-material powder layer of a component along a preset trajectory, step S4 is also included, and real-time online monitoring of the formed component is performed. The component may have defects such as local spheroidization, warping, and large roughness. At this time, the component needs to be laser oscillated and remelted, including step S41: the laser beam uses high-frequency oscillation to remelt the defective target area of ​​the current forming layer along a preset path, so that the surface of the target area is melted and the forming defect is repaired; S42: after step S41 is completed, the forming layer is analyzed again through online monitoring to detect whether the defect has been repaired. If the repair is not completed, return to step S41. If it has been repaired, continue with step S2.

[0106] In this embodiment, laser oscillation remelting is used to reduce the forming defects of the components and greatly improve the forming capabilities of structural features such as variability (such as thin-walled components), lack of support (such as cantilever components), and easy stress concentration (such as sharp-angle components).

[0107] Preferably, the multi-material laser additive manufacturing process provided by the present invention further includes the steps of:

[0108] S5: Online optimization and adjustment of the process, feeding back the adjusted parameter data to the multi-material L-PBF forming process database, thereby updating the parameter data in the multi-material L-PBF forming process database;

[0109] S6: After the component is formed, the quality of the formed component is inspected.

[0110] It should be noted that, in the present invention, descriptions such as "first", "second", "one", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly defined. The terms "connected", "fixed", etc. should be understood in a broad sense. For example, "fixed" can be a fixed connection, a detachable connection, or an integral whole; 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, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0111] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in this field can implement it. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0112] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Persons skilled in the art may make various modifications, additions, or substitutions to the described specific embodiments without departing from the spirit of the present invention or exceeding the scope of the appended claims.

Claims

1. A multi-material laser additive manufacturing process, characterized in that: Including steps: S1: Form a multi-material L-PBF forming process database by training multiple multi-material forming components; S2: Call the multi-material L-PBF forming process database to intelligently segment the current component and plan the powder laying process and laser oscillation forming process for each segmented part. The powder laying process lays multi-material powder layer by layer according to preset requirements and controls the thickness of the multi-material powder layer. The laser oscillation forming process stirs the multi-material molten pool through laser oscillation and shapes the laser beam. S3: forming a multi-material component according to the powder spreading process and laser oscillation forming process in step S1, and combining the powder spreading device and the laser oscillation forming system; The laser oscillation forming process in step S2 includes the following steps: S21: dividing the forming component model of the current multi-material powder layer into an edge region and a filling region, wherein, when the forming component model of the current multi-material powder layer is arranged in a polygonal configuration, the edge region is located at the outer contour edge of the polygon; when the forming component model of the current multi-material powder layer is arranged in a pipe configuration, the edge region is located at the inner contour edge of the pipe; S22: processing the edge area of ​​the component model using a point light source, and processing the filling area of ​​the component model using a surface light source formed by laser oscillation, thereby completing the processing of the component model in the current multi-material powder layer; S23: Using high-power laser high-frequency oscillation to form a uniform surface light source, heat-treating the current multi-material powder layer to eliminate stress concentration or prevent local stress concentration. When the current multi-material powder layer needs to be preheated over a large area, step S23 is performed before step S21; when local high-temperature heat treatment is required for the laser forming area, step S23 is performed simultaneously with step S22; when heat treatment is required for stress concentration-prone areas of the formed component model, step S23 is performed after step S22; S5: Optimize and adjust the process online, and feed the adjusted parameter data back to the multi-material L-PBF forming process database to update the parameter data in the multi-material L-PBF forming process database.

2. The multi-material laser additive manufacturing process according to claim 1, characterized in that: The method further includes step S4: performing real-time online monitoring on the formed component, and if defects occur in the current multi-material powder layer formed component model, performing laser oscillation remelting on the current formed component model.

3. The multi-material laser additive manufacturing process according to claim 2, characterized in that: Step S4 includes the steps of: S41: The laser beam remelts and scans the defective target area of ​​the current forming layer along a preset path in a high-frequency oscillation manner, so that the surface of the target area is melted and the forming defect is repaired; S42: After step S41 is completed, the forming layer is analyzed again through online monitoring to detect whether the defect has been repaired. If not, return to step S41; if repaired, continue to step S2.

4. The multi-material laser additive manufacturing process according to claim 1, characterized in that: Also includes the steps: S6: After the component is formed, the quality of the formed component is inspected.

5. The multi-material laser additive forming process according to any one of claims 1 to 4, which is applicable to a laser oscillation forming system, is characterized in that: The laser oscillation forming system includes: a galvanometer assembly and a CNC machine tool. By adjusting the motion trajectory of the CNC machine tool in the X-axis and Y-axis directions, the laser oscillation stirs the multi-material molten pool during the multi-material L-PBF forming process; by adjusting the distance of the CNC machine tool in the Z-axis direction, the laser spot size can be dynamically controlled.

6. The multi-material laser additive manufacturing process according to claim 5, characterized in that: Laser oscillation forming system includes: A CNC machine tool, comprising a first output shaft movable along an X-axis, a second output shaft movable along a Y-axis, and a third output shaft movable along a Z-axis, wherein the first, second, and third output shafts form a three-coordinate system in space, and a galvanometer assembly provided with a laser light source is connected to the third output shaft; The powder bed is located below the galvanometer assembly and is provided with a multi-material powder layer. The laser light source on the galvanometer assembly realizes laser printing of the multi-material powder layer along a preset trajectory.

7. The multi-material laser additive forming process according to any one of claims 1 to 4, which is applicable to a laser oscillation forming system, is characterized in that: The laser oscillation forming system includes: an ultrasonic driver and a beam expander assembly and a galvanometer assembly in an optical path system. The galvanometer assembly is driven by the ultrasonic driver to achieve stirring of the multi-material molten pool by laser oscillation during the multi-material L-PBF forming process; and the optical path beam expander assembly is driven by the ultrasonic driver to achieve dynamic control of the laser spot size.

8. The multi-material laser additive manufacturing process according to claim 7, characterized in that: Laser oscillation forming system includes: Beam expander assembly, other components in the optical system, and a galvanometer assembly equipped with a laser light source; Two ultrasonic drivers, namely a first ultrasonic driver and a second ultrasonic driver, wherein the first ultrasonic driver is connected to the beam expander assembly, and the second ultrasonic driver is connected to the galvanometer assembly; The powder bed is located below the galvanometer assembly and is provided with a multi-material powder layer. The laser light source on the galvanometer assembly realizes laser printing of the multi-material powder layer along a preset trajectory.

9. The multi-material laser additive forming process according to any one of claims 1 to 4, which is applicable to a laser oscillation forming system, is characterized in that: The laser oscillation forming system includes: a beam expander assembly, a galvanometer assembly, and a rotating mirror assembly in the optical path system. The galvanometer assembly is used to scan the laser in the X-axis and Y-axis directions; the rotating mirror assembly is used to stir the multi-material molten pool by laser oscillation during the multi-material L-PBF forming process, and to dynamically control the laser spot size.

10. The multi-material laser additive manufacturing process according to claim 9, characterized in that: Laser oscillation forming system includes: Beam expander assembly, other components in the optical path system, galvanometer assembly, and rotating mirror assembly equipped with a laser light source; The powder bed is located below the rotating mirror assembly and is provided with a multi-material powder layer. The laser light source on the rotating mirror assembly realizes laser printing of the multi-material powder layer along a preset trajectory.

11. The multi-material laser additive forming process according to any one of claims 1 to 4, which is applicable to a laser oscillation forming system, characterized in that: The laser oscillation forming system includes an optical path system and a spatial light modulator. The spatial light modulator is used to position the laser and plan the scanning path, thereby achieving stirring of the multi-material molten pool by laser oscillation during the multi-material L-PBF forming process and dynamically controlling the laser spot size.

12. The multi-material laser additive manufacturing process according to claim 11, characterized in that: Laser oscillation forming system includes: Other devices in the optical path system and a spatial light modulator equipped with a laser light source; The powder bed is located below the spatial light modulator and has a multi-material powder layer laid on the powder bed. The laser light source on the spatial light modulator realizes laser printing of the multi-material powder layer along a preset trajectory.

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