A method and device for additive manufacturing of parts

Abstract

The present invention discloses a method and equipment for additive manufacturing of parts, which relates to the field of additive manufacturing technology, in order to solve the problems that a large amount of consumables are required in the printing process of existing parts with circular protruding surfaces, and the strength and structural stability of the parts are poor, and they are not easy to form. A method for additive manufacturing of parts, comprising: obtaining a three-dimensional model of a part; determining a forming direction of the part according to the three-dimensional model; determining a circular protruding surface of the part according to the forming direction; constructing a plurality of annular support structures at equal intervals along the radial direction of the circular protruding surface in the three-dimensional model to obtain a processing model of the part; printing the part based on the processing model to obtain a printout; processing the printout to obtain the part. The method and equipment for additive manufacturing of parts provided by the present invention are used for additive manufacturing of parts with circular protruding surfaces, improving the structural strength and structural stability of parts, and reducing the amount of consumables used.

Description

Technical Field

[0001] The present invention relates to the technical field of additive manufacturing, and in particular to a method and equipment for additive manufacturing of parts. Background Art

[0002] Selective Laser Melting (SLM) technology is based on the basic idea of ​​rapid prototyping, that is, a layer-by-layer cladding additive manufacturing method. According to the three-dimensional model of the part, the model is sliced ​​and layered according to a certain thickness, that is, the three-dimensional shape information of the part is converted into a series of two-dimensional contour information. Then, under the control of the CNC system, the laser is used to melt the metal powder through the array mirror control to directly form a part with a specific geometric shape. During the forming process, the metal powder is completely melted to produce a metallurgical bond. It is the latest development of rapid prototyping 3D printing technology. Because the formed parts have good density, it can form high-precision complex special-shaped metal parts, and has the characteristics of high dimensional accuracy, good surface quality, high density and high organizational performance.

[0003] When laser selective melting is used to form metal components, it is often necessary to add supports. At present, the most commonly used support style is mainly block support. Block support can clearly distinguish between the formed part and the support, and the strength of block support is generally lower than that of the formed part, and it is easy to remove in the subsequent processing. However, in actual use, it is difficult and time-consuming to clean the metal powder in the block support. For parts with large-area circular protruding surfaces, large-area block supports are required, which consumes a large amount of materials. If block supports are used, the strength of the parts will be low, the structural stability will be poor, and it will be difficult to form. Summary of the invention

[0004] The purpose of the present invention is to provide a method and equipment for additive manufacturing of parts, which is used to solve the problems that a large amount of consumables are required in the printing process of existing parts with circular protruding surfaces, the strength and structural stability of the parts are poor, and the parts are difficult to form.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] In one aspect, the present invention provides a method for additive manufacturing of a part, comprising:

[0007] Obtain a 3D model of the part;

[0008] Determining a forming direction of the part according to the three-dimensional model;

[0009] Determining a circular protruding surface of the part according to the forming direction;

[0010] Constructing a plurality of annular support structures at equal intervals along the radial direction of the circular emergent surface in the three-dimensional model to obtain a processing model of the part;

[0011] Printing the part based on the processing model to obtain a printed part;

[0012] The printed part is processed to obtain the part.

[0013] Compared with the prior art, the invention provides a method for additive manufacturing of parts, which determines the forming direction of the part according to the obtained three-dimensional model of the part; determines the circular emergent surface of the part according to the forming direction; constructs multiple annular support structures at equal intervals along the radial direction of the circular emergent surface in the three-dimensional model to obtain a processing model of the part; prints the part based on the processing model to form a printed part; and processes the printed part to obtain the part. The multiple annular support structures constructed are evenly distributed on the circular emergent surface and cover the entire circular emergent surface, thereby ensuring the strength of the part and improving the structural stability. At the same time, the setting of the annular support structure effectively reduces the amount of consumables, reduces the manufacturing cost of the part, and reduces the printing time. Moreover, the contact area between the annular support structure and the substrate and the part is small, which is easy to remove and shortens the manufacturing cycle. In addition, during the part forming process, since there are intervals between the annular structures, powder accumulation will not occur, which reduces the difficulty of part forming.

[0014] The present invention also provides a part additive manufacturing device, including a processor and a communication interface coupled to the processor; the processor is used to run a computer program or instruction to implement the above-mentioned part additive manufacturing method.

[0015] Compared with the prior art, the beneficial effects of the parts additive manufacturing equipment provided by the present invention are the same as the beneficial effects of the parts additive manufacturing method described in the above technical solution, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0017] Figure 1 A flowchart of a part additive manufacturing method provided by the present invention;

[0018] Figure 2 A schematic diagram of the structure of a part with a circular protruding surface provided by the present invention;

[0019] Figure 3 A schematic diagram of the forming direction of a part provided by the present invention;

[0020] Figure 4 A schematic diagram of the structure of parts for constructing an annular support structure provided by the present invention;

[0021] Figure 5A schematic diagram of the structure of the hollowed-out portion of the annular support structure provided by the present invention;

[0022] Figure 6 A partial cross-sectional view of a part provided by the present invention;

[0023] Figure 7 This is a structural block diagram of a part additive manufacturing device provided by the present invention.

[0024] Reference numerals:

[0025] 1- circular emergent surface, 2- circular bottom surface, 3- annular supporting structure, 4- window-shaped structure. DETAILED DESCRIPTION

[0026] In order to clearly describe the technical solutions of the embodiments of the present invention, in the embodiments of the present invention, words such as "first" and "second" are used to distinguish the same items or similar items with basically the same functions and effects. For example, the first threshold and the second threshold are only used to distinguish different thresholds, and their order is not limited. Those skilled in the art can understand that words such as "first" and "second" do not limit the quantity and execution order, and words such as "first" and "second" do not necessarily limit them to be different.

[0027] It should be noted that, in the present invention, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0028] In the present invention, "at least one" means one or more, and "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b or c can mean: a, b, c, the combination of a and b, the combination of a and c, the combination of b and c, or the combination of a, b and c, where a, b, c can be single or multiple.

[0029] More and more special-shaped parts are being manufactured through laser selective melting technology. However, the existing additive manufacturing methods for parts with large protruding surfaces often use the method of adding block supports for manufacturing. This method is prone to powder accumulation, which makes the block supports higher than the printing surface, resulting in part printing failure. In addition, due to stress accumulation, it is easy to deform and crack.

[0030] Based on the above problems, the present invention provides a part additive manufacturing method and equipment for printing and forming parts with circular protruding surfaces. The part additive manufacturing method is applied to a laser selective melting forming system, and the laser selective melting forming system includes a printing device. Next, the part additive manufacturing method provided by the present invention is described in conjunction with the accompanying drawings.

[0031] Figure 1 A flowchart of a part additive manufacturing method provided by the present invention, such as Figure 1 As shown, the method comprises the following steps:

[0032] Step 101: Obtain a three-dimensional model of the part.

[0033] The 3D model of the part is constructed in 3D software according to the actual size of the part. The 3D software can be UG, Pro / engineer, etc. The 3D software can be selected according to actual needs. This is just an example and is not specifically limited.

[0034] The 3D software is used to construct Figure 2 The 3D model of the part shown, Figure 2 The part in FIG. 1 is a part having a circular protruding surface 1.

[0035] Step 102: Determine a forming direction of the part according to the three-dimensional model.

[0036] The forming direction of the part is the direction of increasing height during the deposition process. The forming direction is based on the principle of low printing height, less support and short forming time. Figure 3 The forming direction is selected according to the structural characteristics of the part. Figure 2 and Figure 3 It can be seen that the part has two coaxial cylinders, one large and one small, with four cuboids on top of the larger cylinder. Figure 3 When printing parts in the forming direction shown, only the circular protruding surface 1 of the larger cylinder will have no support, and the rest of the structure will have support. Therefore, it is only necessary to build support on the part corresponding to the circular protruding surface 1, and Figure 3 The part print height in the forming direction is the lowest.

[0037] Step 103: determining the circular protruding surface of the part according to the forming direction.

[0038] A circular emergent surface is a circular, suspended surface. Figure 2 ,according to Figure 3 The determined forming direction can determine the circular protruding surface 1 of the part. Although the circular bottom surface 2 is also a circular surface, according to the forming direction, it can be known that the circular bottom surface 2 will contact the substrate as the bottom of the entire part during the forming process of the part, and is not a suspended surface. Therefore, the circular bottom surface 2 is not a circular protruding surface.

[0039] Step 104: constructing a plurality of annular support structures at equal intervals in the three-dimensional model along the radial direction of the circular emergent surface to obtain a processing model of the part.

[0040] like Figure 4 As shown, multiple annular support structures 3 are sequentially constructed from the outer edge of the circular emergent surface along the radial direction of the circular emergent surface. The multiple annular support structures 3 are used to provide support for the structure corresponding to the circular emergent surface of the part, so the height of the annular support structure 3 is the same as the distance between the circular emergent surface and the bottom of the part.

[0041] Specifically, in the same part manufacturing process, the thickness of each annular support structure 3 constructed should be the same, the thickness of the annular support structure 3 can be selected in the range of 1-3 mm, and the distance between two adjacent annular support structures 3 can be in the range of 1-6 mm.

[0042] As an optional manner, each of the annular support structures is evenly provided with hollow parts.

[0043] Providing a hollow portion on each annular support structure can reduce the weight of the annular support structure 3, save materials, and reduce stress concentration.

[0044] As an optional method, the hollow portion can be as follows Figure 5 The window-shaped structure 4 shown has a highest point 5 mm away from the circular protruding surface of the part, a window width of 20 mm, an upper bevel angle of 50°, and a distance of 15 mm between each window-shaped structure 4.

[0045] The hollow portion is set as a window-shaped structure 4 to minimize the remaining entity of the annular support structure, while ensuring the support strength of the annular support structure. In addition, the hollow portion is set in the shape of a window-shaped structure 4 to avoid adding additional support to the hollow portion. It is understandable that the hollow portion can also be selected from a variety of other forms as needed, such as circular, diamond, arched, etc., which are only examples and are not specifically limited here.

[0046] As an optional manner, the part is printed based on the processing model to obtain a printed part, and the process also includes:

[0047] A fillet structure is constructed between each of the annular support structures and the part in the three-dimensional model.

[0048] See also Figure 6 The fillet structure 5 is arranged between the annular support structure 3 and the circular protruding surface 1 of the part. Except for the outermost annular support structure 3 and the part, two fillet structures 5 are arranged between the other annular support structures 3 and the part. The fillet structure is also an annular structure, and the radius of the circular part of the fillet structure 5 is half of the distance between the two adjacent annular support structures 3. The arrangement of the fillet structure 5 can reduce stress concentration and avoid cracking at the part where the circular protruding surface 1 of the part contacts the annular support structure 3.

[0049] Step 105: Print the part based on the processing model to obtain a printout.

[0050] When printing, the processing model of the part is first exported as an SLT format file. When exporting the file, the triangular tolerance and adjacent tolerance are both set to 0.0025mm. Then the processing model of the part is sliced, imported into the printing device, and printed in the forming direction to obtain the printout. During the printing process, multiple annular support structures are formed together with the part.

[0051] Step 106: Process the printout to obtain the part.

[0052] As an optional manner, the step of processing the printout to obtain the part includes:

[0053] A plurality of the annular support structures are cut to obtain the parts.

[0054] The part additive manufacturing method provided by the present invention is applied to a laser selective melting forming system with a printing device. When it is specifically implemented, in the part forming process, firstly, a three-dimensional model of the part is established using modeling software such as UG / or Pro / engineer; then the forming direction is determined according to the principle of low printing height and less support; the three-dimensional model of the part is opened in magics software, the support angle is set to 45°, the circular protruding surface and the area for constructing the support are determined, multiple annular support structures are constructed, a rounded corner structure is constructed, and at the same time, a hollow portion of a window-shaped structure with equal intervals is set in each annular support structure; then the constructed processing model is exported to SLT format, sliced, imported into the equipment, and printed to complete the part manufacturing.

[0055] According to the above-mentioned parts additive manufacturing method and specific implementation process, the parts additive manufacturing method ensures the strength of the parts and improves the structural stability by constructing multiple annular support structures that are evenly distributed on the circular protruding surface and cover the entire circular protruding surface. At the same time, the setting of the annular support structure effectively reduces the amount of consumables, reduces the part manufacturing cost, reduces the printing time, and the annular support structure has a small contact area with the substrate and the part, is easy to remove, and shortens the manufacturing cycle; in addition, during the part forming process, due to the intervals between the annular structures, powder accumulation will not occur, reducing the difficulty of part forming.

[0056] In the case of using the corresponding integrated unit, Figure 7 FIG. 1 is a block diagram of a part additive manufacturing device provided by an embodiment of the present invention. Figure 7 As shown, the part additive manufacturing equipment includes: a communication unit and a processing unit.

[0057] A communication unit / communication interface for obtaining a three-dimensional model of a part;

[0058] A processing unit / processor, configured to determine a forming direction of the part according to the three-dimensional model;

[0059] Determining a circular protruding surface of the part according to the forming direction;

[0060] Constructing a plurality of annular support structures at equal intervals along the radial direction of the circular emergent surface in the three-dimensional model to obtain a processing model of the part;

[0061] Printing the part based on the processing model to obtain a print part;

[0062] The printed part is processed to obtain the part.

[0063] The above-mentioned parts additive manufacturing equipment is built on a printing device for use. At the same time, the parts additive manufacturing equipment provided by the present invention corresponds to a parts additive manufacturing method, which acts on the printing device.

[0064] like Figure 7 As shown, the processor may be a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of the program of the present invention. The communication interface may be one or more. The communication interface may use any transceiver-like device for communicating with other devices or communication networks.

[0065] like Figure 7As shown, the terminal device may further include a communication line. The communication line may include a path to transmit information between the components.

[0066] Optional, such as Figure 7 As shown, the terminal device may further include a memory. The memory is used to store computer-executable instructions for executing the solution of the present invention, and the execution is controlled by the processor. The processor is used to execute the computer-executable instructions stored in the memory, thereby implementing the method provided by the embodiment of the present invention.

[0067] like Figure 7 As shown, the memory may be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a random access memory (RAM) or other types of dynamic storage devices that can store information and instructions, or an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical disc, laser disc, optical disc, digital versatile disc, Blu-ray disc, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory may exist independently and be connected to the processor through a communication line. The memory may also be integrated with the processor.

[0068] Optionally, the computer-executable instructions in the embodiment of the present invention may also be referred to as application program codes, which is not specifically limited in the embodiment of the present invention.

[0069] In a specific implementation, as an example, Figure 7 As shown, the processor may include one or more CPUs, such as Figure 7 CPU0 and CPU1 in.

[0070] In a specific implementation, as an example, Figure 7 As shown, the terminal device may include multiple processors, such as Figure 7 Each of these processors can be a single-core processor or a multi-core processor.

[0071] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instruction is loaded and executed on a computer, the process or function described in the embodiment of the present invention is executed in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, a terminal, a user device or other programmable device. The computer program or instruction can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer program or instruction can be transmitted from one website site, computer, server or data center to another website site, computer, server or data center by wired or wireless means. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that integrates one or more available media. The available medium can be a magnetic medium, such as a floppy disk, a hard disk, or a tape; it can also be an optical medium, such as a digital video disc (DVD); it can also be a semiconductor medium, such as a solid state drive (SSD).

[0072] Although the present invention is described herein in conjunction with various embodiments, in the process of implementing the claimed invention, those skilled in the art may understand and implement other variations of the disclosed embodiments by viewing the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other components or steps, and "one" or "an" does not exclude multiple situations. A single processor or other unit may implement several functions listed in the claims. Certain measures are recorded in different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

[0073] Although the present invention has been described in conjunction with specific features and embodiments thereof, it is apparent that various modifications and combinations may be made thereto without departing from the spirit and scope of the present invention. Accordingly, this specification and the accompanying drawings are merely exemplary illustrations of the present invention as defined by the appended claims and are deemed to cover any and all modifications, variations, combinations or equivalents within the scope of the present invention. Obviously, those skilled in the art may make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, the present invention is intended to include such modifications and variations if they fall within the scope of the claims of the present invention and their equivalents.

Claims

1. A method for additive manufacturing of parts, characterized in that: include: Obtain a 3D model of the part; Determining a forming direction of the part according to the three-dimensional model; Determining a circular protruding surface of the part according to the forming direction; the circular protruding surface is a circular suspended surface; In the three-dimensional model, a plurality of annular support structures with the same thickness are constructed at equal intervals along the radial direction of the circular protruding surface to obtain a processing model of the part; the height of the annular support structure is the same as the distance between the circular protruding surface and the bottom of the part; Each of the annular support structures is evenly provided with a hollow portion, and the hollow portion is a window-shaped structure; the highest point of the window-shaped structure is 5 mm away from the part, the window width of the window-shaped structure is 20 mm, and the upper bevel angle of the window of the window-shaped structure is 50°; constructing a fillet structure between each of the annular support structures and the part in the three-dimensional model; The radius of the fillet structure is half of the distance between two adjacent annular support structures; Except for one rounded corner structure provided between the outermost annular support structure and the part, two rounded corner structures are provided between the other annular support structures and the part; Printing the part based on the processing model to obtain a print part; A plurality of the annular support structures are cut to obtain the parts.

2. The method according to claim 1, characterized in that The distance between two adjacent window-shaped structures is 15 mm.

3. The method according to claim 1, characterized in that: The thickness of the annular support structure is in the range of 1-3 mm.

4. The method according to claim 1, characterized in that: The distance between two adjacent annular support structures ranges from 1 to 6 mm.

5. A part additive manufacturing device, characterized in that: include: A processor and a communication interface coupled to the processor; the processor is used to run a computer program or instruction to implement the part additive manufacturing method as described in any one of claims 1 to 4.

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