Additive manufacturing system, additive manufacturing method and computer readable medium

Abstract

An additive manufacturing system is provided. The additive manufacturing system includes an additive manufacturing unit, a surface treatment unit, and a control unit. The additive manufacturing unit includes a material supply device configured to supply a material to a substrate for layer-by-layer additive manufacturing, and a heat source device adapted to provide a heat source for layer-by-layer melting of the material to form a material layer. The surface treatment unit is configured to perform a surface treatment on the material layer. The control unit is configured to control the additive manufacturing unit and the surface treatment unit. The surface treatment unit is configured to perform the surface treatment on an Nth material layer after the Nth material layer is formed and before an (N+1)th material layer is formed on the Nth material layer, where N is an integer greater than or equal to 1. An additive manufacturing method and a computer readable medium embodying the additive manufacturing method are also provided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of material processing, and in particular, to an additive manufacturing system and an additive manufacturing method for melting and depositing materials to perform additive manufacturing. BACKGROUND

[0002] Additive layer manufacturing (ALM) is a technique in which a product is designed using a computer and then printed using a printer. In the computer design, a model of the product to be formed is created, the model is divided into a plurality of 2D layers, and the design data of each layer is stored in the computer for printing. In the printing process, a material is continuously printed (i.e., melted and deposited) layer by layer using a heat source until a final 3D product is formed.

[0003] However, there are many defects such as pores, cracks, slag, and unmelted defects between the layers of the formed 3D product. These defects can affect the quality, performance, and service life of the product. Currently, there is no effective or economical way to inspect and control the interlayer defects of the product (especially large products).

[0004] In addition, after layer-by-layer processing, the product has a large layer accumulation manufacturing error, which significantly reduces the processing accuracy of the product. SUMMARY

[0005] The purpose of the present application is to provide an additive manufacturing system and an additive manufacturing method capable of reducing interlayer defects and / or improving processing accuracy.

[0006] According to one aspect of the present disclosure, an additive manufacturing system is provided. The additive manufacturing system includes an additive manufacturing unit, a surface treatment unit, and a control unit. The additive manufacturing unit includes a material supply device configured to supply a material to a substrate for layer-by-layer additive manufacturing, and a heat source device adapted to provide a heat source for layer-by-layer melting or sintering of the material to form a material layer. The surface treatment unit is configured to perform surface treatment on the material layer. The control unit is configured to control the additive manufacturing unit and the surface treatment unit. The surface treatment unit is configured to perform surface treatment on an Nth material layer after the Nth material layer is formed and before an (N+1)th material layer is formed on the Nth material layer, where N is an integer greater than or equal to 1.

[0007] In the additive manufacturing system of the present disclosure, since the surface treatment device for treating the material layer is provided, the interlayer defects can be reduced to improve the mechanical properties of the product. In addition, the surface treatment of the material layer by the surface treatment device can eliminate the layer processing error, thereby avoiding the cumulative processing error of the product, so that the dimensional accuracy of the product can be improved and ensured.

[0008] The additive manufacturing system according to the present disclosure can improve the performance and quality of the product. When the formed product can meet the use requirements, it can be exempted from post-processing, which is particularly advantageous for large products.

[0009] In addition, since the surface treatment is performed on the material layer after the material layer is formed, the requirement for the processing environment can be reduced. For example, it is not necessary to process the product in a vacuum environment or vacuum chamber.

[0010] In some examples of the additive manufacturing system, the surface treatment unit is configured to perform surface treatment on each of the material layers after the material layer is formed.

[0011] In some examples of the additive manufacturing system, the surface treatment unit comprises a polishing device. In particular, the polishing device can be a laser polishing device.

[0012] In some examples of the additive manufacturing system, the heat source device is a laser heat source device or an electric arc heat source device.

[0013] The surface treatment device and / or the heat source device can be selected according to the material type, the product processing process parameters.

[0014] In some examples of the additive manufacturing system, the heat source device is a non-gas tungsten arc welding machine, and / or along the formation direction of the material layer, the non-gas tungsten arc welding machine is located behind the molten pool, and the material supply device is located in front of or behind the molten pool.

[0015] In some examples of the additive manufacturing system, the heat source device is a gas tungsten arc welding machine, and / or along the formation direction of the material layer, the gas tungsten arc welding machine is located behind the molten pool.

[0016] In some examples of the additive manufacturing system, the heat source device and the surface treatment unit are configured to be movable relative to the substrate.

[0017] According to another aspect of the present disclosure, an additive manufacturing method is provided. The additive manufacturing method comprises: supplying a material to a substrate by a material supply device so as to perform layer-by-layer additive manufacturing; and melting the material layer by layer by a heat source device to form a material layer. The method further comprises: performing surface treatment on the Nth material layer by a surface treatment unit after the Nth material layer is formed, and then forming an N+1th material layer on the Nth material layer, wherein N is an integer greater than or equal to 1.

[0018] In some examples of the additive manufacturing method, the surface treatment unit performs surface treatment on each of the material layers after the material layer is formed.

[0019] In some examples of the additive manufacturing method, the surface processing unit performs a laser polishing process on the material layer.

[0020] In some examples of the additive manufacturing method, the method may further include: moving the heat source device and the surface treatment unit relative to the substrate during the additive manufacturing and the surface treatment.

[0021] According to another aspect of the present disclosure, a computer-readable medium is provided, on which a program is stored. When the program is executed by a processor of a control unit, the above-mentioned additive manufacturing method is implemented.

[0022] Other advantages and features of the present invention will become apparent from the following non-limiting detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The features and advantages of one or more embodiments of the present invention will become more readily understood through the following description with reference to the accompanying drawings, in which:

[0024] Figure 1 is a schematic diagram of functional modules of an additive manufacturing system according to the present disclosure;

[0025] Figures 2A to 2D is a schematic diagram of various processing stages of an additive manufacturing system according to an embodiment of the present disclosure;

[0026] Figure 3 is a schematic structural diagram of an additive manufacturing system according to another embodiment of the present disclosure;

[0027] Figure 4 is a schematic structural diagram of an additive manufacturing system according to another embodiment of the present disclosure;

[0028] Figure 5 is a schematic structural diagram of an additive manufacturing system according to yet another embodiment of the present disclosure; and

[0029] Figure 6 is a flow chart of an additive manufacturing method according to an embodiment of the present disclosure.

[0030] Corresponding reference characters indicate corresponding parts throughout the several views of the drawings. DETAILED DESCRIPTION

[0031] The present invention will be described in detail below with reference to the accompanying drawings and exemplary embodiments. The following detailed description of the present invention is for illustrative purposes only and is in no way intended to limit the present invention, its application or use.

[0032] Figure 1is a functional block diagram of an additive manufacturing system 10 according to the present disclosure. The additive manufacturing system 10 is a system for forming a product layer by layer using an additive manufacturing technique (ALM). As shown in Figure 1 The additive manufacturing system 10 includes an additive manufacturing unit 12 for forming a material layer 11, a surface treatment unit 14 for surface treating the formed material layer 11, and a control unit 15 for controlling the additive manufacturing unit 12 and the surface treatment unit 14.

[0033] The additive manufacturing unit 12 includes a material supply device 12a and a heat source device 12b. The material supply device 12a is configured to supply a material to a substrate S (as shown in Figure 2A The heat source device 12b is configured to melt or sinter the material layer by layer to form the material layer 11.

[0034] The surface treatment unit 14 surface treats the material layer 11 after the material layer 11 is formed. For example, the material layer 11 is polished to remove slag, burrs, cracks, oxide layers, etc., so that the surface of the material layer 11 is smooth or manufacturing errors are eliminated, thereby improving the quality, performance, or dimensional accuracy of the material layer. For example, the material layer 11 is laser treated to improve the microstructure of the material layer 11 to a certain extent, so that it has a certain degree of cleanliness or desired roughness, thereby improving its mechanical properties, etc. For example, the material layer 11 is cleaned to remove impurities or contaminants, etc., thereby enhancing the bonding force between the material layers, thereby improving the physical and chemical properties of the formed product, etc. The surface treatment can vary depending on the additive manufacturing process, performance, etc. requirements of the product.

[0035] The product formed by the accumulation of the surface treated material layers 11 can have the desired performance and quality, so that post-processing of the product can be omitted or reduced. This is particularly advantageous for large products.

[0036] Since the additive manufacturing system 10 according to the present disclosure can surface treat the material layer 11 after the material layer 11 is formed, the environmental requirements for additive manufacturing of the product can be reduced, for example, additive manufacturing can be performed in an open air environment, i.e. a vacuum chamber can be omitted.

[0037] The control unit 15 controls the operation and switching of the additive manufacturing unit 12 and the surface treatment unit 14 according to the data of the product modeling and slicing. For example, the control unit 15 can control the additive manufacturing unit 12 (material supply device 12a and heat source device 12b) and the surface treatment unit 14 relative to the substrate movement. The substrate can be fixed, thereby ensuring higher molding accuracy.

[0038] Figures 2A to 2DAn additive manufacturing system 100 and its respective processing stages according to one embodiment of the present disclosure are shown. As shown, the additive manufacturing system 100 includes a substrate S, a wire feeder 120 as a material supply device 12a for supplying wire material to the substrate S, a laser heat source device 140 as a heat source device 12b for melting the material to form a melt pool 110, and a laser polishing device 160 constituting a surface treatment unit 14 for surface treating the material layer.

[0039] It should be understood that the respective components of the additive manufacturing system 100 are only schematically shown in the drawings. For example, the substrate S shown in the drawings is generally flat. However, it should be understood that the substrate S shown in the drawings is only schematic. The substrate S refers to a worktable or support structure on which the product is processed, and thus the shape and size of the substrate S can vary depending on the structure of the product to be shaped or the processing requirements.

[0040] Figure 2A An additive manufacturing of an Nth material layer of the product is shown. As shown, an (N-1)th material layer has been formed on the substrate S, and the additive manufacturing unit 12 is processing and forming the Nth material layer. Here, N can be understood as the number of material layers. During the additive manufacturing, the wire feeder 120 supplies wire material on the (N-1)th material layer along a direction D, and the laser heat source device 140 projects laser onto the material to melt it to form the melt pool 110. The material layer is formed as the wire material is supplied, melted, and solidified.

[0041] In Figure 2A In the example shown, the laser heat source device 140 is generally perpendicular to the substrate S, while the wire feeder 120 is arranged obliquely at an angle β with respect to the laser heat source device 140. That is, the central axis of the wire feeder 120 is at an angle β with respect to the central axis of the laser heat source device 140. The angle β can be determined according to the material supply rate, heat source power, etc. The wire feeder 120 is located in front of the melt pool 110 along the direction of formation of the Nth material layer, so that the wire material can be preheated. It should be understood that the laser heat source device 140 and the wire feeder 120 can be arranged in other ways as long as they can achieve the functions described herein. For example, as shown in FIG. 6, the wire feeder 120 is located behind the melt pool 110 along the direction of formation of the Nth material layer. Figure 5

[0042] Figure 2B A surface treatment of the Nth material layer after the formation of the Nth material layer is shown. In Figure 2B ​In the embodiment, the Nth material layer is polished by the laser polishing device 160. The surface subjected to the polishing is the surface on which the N+1th material layer is to be formed. By polishing the Nth material layer, the processing defects can be reduced to improve the quality and performance of the Nth material layer, the bonding between the Nth material layer and the N+1th material layer can be enhanced, and the processing errors can be eliminated to ensure the dimensional accuracy of the material layers of the product.

[0043] Figure 2C The additive manufacturing of the N+1th material layer is shown. As shown, the Nth material layer has been formed on the substrate S, and the additive manufacturing unit 12 is processing and forming the N+1th material layer. Specifically, the wire feeding device 120 feeds the wire along the direction D on the Nth material layer, and the laser heat source device 140 projects the laser onto the material to melt it so as to form the N+1th material layer.

[0044] Figure 2D The surface treatment of the N+1th material layer is shown. In the embodiment, the N+1th material layer is polished by the laser polishing device 160. The surface subjected to the polishing is the surface on which the N+2th material layer is to be formed. Figure 2D

[0045] The surface treatment device (e.g., the laser polishing device 160) according to the present disclosure performs surface treatment on the material layer, and thus the processing process of the surface treatment device, the structure and operation of the surface treatment device and its control device, etc. can be simplified.

[0046] In the existing additive manufacturing system, the surface treatment (e.g., polishing treatment) is often performed on the product after it is formed to meet the appearance requirements or overall size requirements of the product. After the product is formed, it has a complex shape (e.g., concave-convex structure, sharp corners, holes, etc.), and thus a large surface treatment device is required, and the structure and operation of the surface treatment device become complex, which is not easy to control or ensure the surface treatment quality. In addition, the surface treatment after the product is formed cannot solve the problem of interlayer defects, nor can it eliminate the layer processing errors, which eventually leads to a large accumulated processing error.

[0047] In the embodiment of the present disclosure, the surface treatment is performed immediately after the formation of a material layer of the product and before the formation of the next layer thereon, so that various defects in the material layer can be effectively removed, which will not be accumulated as interlayer defects in the final product, and the manufacturing error of the final product can be reduced.

[0048] In the embodiment, the Nth material layer is polished by the laser polishing device 160. The surface subjected to the polishing is the surface on which the N+1th material layer is to be formed. By polishing the Nth material layer, the processing defects can be reduced to improve the quality and performance of the Nth material layer, the bonding between the Nth material layer and the N+1th material layer can be enhanced, and the processing errors can be eliminated to ensure the dimensional accuracy of the material layers of the product. Figures 2A to 2D ​In the example shown, the laser heat source device 140 and the laser polishing device 160 can use different lasers (not shown). This allows for greater design flexibility for the laser heat source device 140 and the laser polishing device 160. It should be understood that the laser heat source device and the laser polishing device can use the same laser, which can reduce costs or make the additive manufacturing system more compact.

[0049] It should be understood that, depending on the processing or performance requirements of different material layers of a product, different surface treatment devices can be used to surface treat different material layers. Surface treatment can be performed on every material layer, or on predetermined material layers to meet their specific requirements. For example, a material layer that is subject to greater stress during use can be surface treated to enhance its load-bearing capacity, while a material layer that is subject to less stress during use can be left untreated. This ensures both product quality and performance requirements while increasing production efficiency.

[0050] exist Figures 2A to 2D In the example shown in FIG. 1 , the material supply device 12 a is a wire feeding device 120 for supplying wire material.

[0051] Figure 3 An additive manufacturing system 200 according to another embodiment of the present disclosure is shown. Figure 3 Additive Manufacturing System 200 and Figures 2A to 2D The same parts of the additive manufacturing system 100 are represented by the same reference numerals, and their detailed description is omitted. Figure 3 Additive Manufacturing System 200 and Figures 2A to 2D Different parts of the additive manufacturing system 100.

[0052] The additive manufacturing system 200 differs from the additive manufacturing system 100 in that it uses a metal inert gas (MIG) welder 240 as a heat source device. The metal inert gas welder 240 provides an arc heat source for melting or sintering materials.

[0053] like Figure 3 As shown, the MIG welder 240 and the wire feeder 220 are located on the same side of the molten pool 210. Along the formation direction D of the N+1 material layer (or the moving direction of the MIG welder 240), the MIG welder 240 (and the wire feeder 220) can be located behind the molten pool, which can reduce the cooling rate of the molten pool. The inert gas shielded welder 240 can be integrated with the wire feeder 220. The inert gas shielded welder 240 and the wire feeder 220 can be arranged at an angle α relative to the vertical direction. The angle α can vary according to the type of material, the feed rate of the material, etc.

[0054] Figure 4 An additive manufacturing system 300 according to yet another embodiment of the present disclosure is shown. The additive manufacturing system 300 differs from the additive manufacturing system 200 in that it employs a non-gas tungsten arc welding machine 340 as the heat source device. The non-gas tungsten arc welding machine is, for example, a tungsten inert gas (TIG) welding machine. Similar to the gas tungsten arc welding machine 240, the non-gas tungsten arc welding machine 340 provides an arc heat source for melting or sintering the material.

[0055] In the example shown, the wire feeder 320 and the non-gas tungsten arc welding machine 340 can be located on opposite sides of the molten pool 310. Along the direction D of formation of the N+1 material layer (or, the direction of movement of the non-gas tungsten arc welding machine 340), the wire feeder 320 is disposed obliquely in front of the molten pool 310 at an angle β with respect to the vertical direction, while the non-gas tungsten arc welding machine 340 is disposed obliquely behind the molten pool 310 at an angle a with respect to the vertical direction. Depending on different process parameters, the angle a and the angle β can vary. Figure 4 It should be understood that the arrangement of the wire feeder 320 and the non-gas tungsten arc welding machine 340 is not limited to the specific example shown, but can vary according to actual needs. For example, the wire feeder 320 can be located behind the molten pool 310 along the direction D of formation of the material layer.

[0056] Figure 4 It should be understood that the arrangement of the wire feeder 320 and the non-gas tungsten arc welding machine 340 is not limited to the specific example shown, but can vary according to actual needs. For example, the wire feeder 320 can be located behind the molten pool 310 along the direction D of formation of the material layer.

[0057] The appropriate heat source device can be selected according to the selected material or process parameters.

[0058] Figure 6 is a flowchart of an additive manufacturing method according to an embodiment of the present disclosure. As shown, the additive manufacturing method includes the following steps: Figure 6 ​As shown, at step S10, a product to be manufactured is designed on a computer, including modeling the product, slicing the model, and loading the slice data onto the computer or control unit. Then, at step S20, the additive manufacturing system is initiated for additive manufacturing. Through additive manufacturing, at step S30, an Nth layer of material is manufactured and formed, where N can be an integer greater than or equal to 1. Next, at step S40, the formed Nth layer of material is surface treated (e.g., polished or laser treated) to eliminate inter-layer defects or layer manufacturing errors. Thereafter, the Nth layer of material is continued to be manufactured and a next layer of material is formed thereon. At step S50, an N+1th layer of material is manufactured. Next, at step S60, the formed N+1th layer of material is surface treated to, for example, eliminate inter-layer defects or layer manufacturing errors. Then, if it is determined at step S65 that the final product has not been formed, then the process returns to step S30 and the manufacturing of the layer of material is continued, i.e., the above steps are repeated. If it is determined at step S65 that the additive manufacturing and surface treatment processes have been completed, then the process proceeds to step S70, i.e., the product is formed. After the product is formed, the product can also be post-processed as needed, as shown at step S80. The post-processing includes, for example, heat treatment, machining, cleaning, and the like.

[0059] It should be understood that the additive manufacturing method according to the present disclosure is not limited to the example shown in FIG. 1. For example, the post-processing at step S80 can be omitted, particularly when the product has met the dimensional or performance requirements, etc. Figure 6

[0060] The control unit in the present disclosure can include a processor implemented as a computer. The method of additive manufacturing described herein can be implemented by one or more computer programs executed by the computer processor. The computer programs include processor-executable instructions stored on a non-transitory tangible computer readable medium. The computer programs can also include stored data. Non-limiting examples of non-transitory tangible computer readable media are non-volatile memory, magnetic storage, and optical storage.

[0061] The term computer readable medium does not include a transitory propagating signal or electromagnetic wave propagating through a medium, such as on a carrier; the term computer readable medium can therefore be regarded as tangible and non-transitory. Non-limiting examples of non-transitory tangible computer readable media are non-volatile memory (e.g., flash memory, erasable programmable read only memory, or mask read only memory), volatile memory (e.g., static random access memory circuitry or a dynamic random access memory), magnetic storage (e.g., analog magnetic tape or digital magnetic tape or a hard disk drive), and optical storage (e.g., CD, DVD, or Blu-ray).

[0062] ​While the application has been described with reference to the example embodiments thereof, it is to be understood that the application is not limited to the specific embodiments nor compositions described herein, as such may, of course, vary within the scope of the appended claims.

Claims

1. An additive manufacturing system comprising: an additive manufacturing unit, the additive manufacturing unit comprising a material supply device and a heat source device, the material supply device being configured to supply material to a substrate for layer-by-layer additive manufacturing; The heat source device is suitable for providing a heat source for melting the material layer by layer to form a material layer, wherein along the forming direction of the material layer, the heat source device and the material supply device are located behind the molten pool; a surface treatment unit configured to perform surface treatment on the material layer, and a control unit configured to control the additive manufacturing unit and the surface treatment unit, The surface treatment unit is configured to perform surface treatment on the Nth material layer after forming the Nth material layer and before forming the N+1th material layer on the Nth material layer, wherein N is an integer greater than or equal to 1.

2. The additive manufacturing system according to claim 1, wherein: The surface treatment unit is configured to perform surface treatment on each of the material layers after the material layer is formed.

3. The additive manufacturing system according to claim 1 or 2, wherein: The surface treatment unit includes a polishing device.

4. The additive manufacturing system according to claim 3, wherein: The polishing device is a laser polishing device.

5. The additive manufacturing system according to claim 1 or 2, wherein: The heat source device is a laser heat source device or an arc heat source device.

6. The additive manufacturing system according to claim 1 or 2, wherein: The heat source device is a non-melting-polarity inert gas shielded welding machine.

7. The additive manufacturing system according to claim 1 or 2, wherein: The heat source device is a metal inert gas shielded welding machine.

8. The additive manufacturing system according to claim 1 or 2, wherein: The heat source device and the surface treatment unit are configured to be movable relative to the substrate.

9. An additive manufacturing method comprising: supplying material to the substrate via a material supply device for layer-by-layer additive manufacturing; as well as The material is melted layer by layer by a heat source device to form a material layer, wherein along the forming direction of the material layer, the heat source device and the material supply device are located behind the molten pool; The method further includes: performing surface treatment on the Nth material layer by a surface treatment unit after forming the Nth material layer, and then forming an N+1th material layer on the Nth material layer, where N is an integer greater than or equal to 1.

10. The additive manufacturing method according to claim 9, wherein: The surface treatment unit performs surface treatment on each of the material layers after the material layer is formed.

11. The additive manufacturing method according to claim 9 or 10, wherein: The surface processing unit performs laser polishing on the material layer.

12. The additive manufacturing method according to claim 9 or 10, further comprising: During additive manufacturing and surface treatment, the heat source device and the surface treatment unit are moved relative to the substrate.

13. A computer-readable medium having a program stored thereon, wherein when the program is executed by a processor of a control unit, the additive manufacturing method according to any one of claims 9 to 12 is implemented.

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