Powder-laying laser additive manufacturing device and method

Abstract

The present invention discloses a powder-laying laser additive forming device, comprising a laser sintering mechanism, a frame, and a powder-laying trough provided at the bottom of the frame with an upwardly facing notch. A powder bed lifting mechanism is provided in the powder-laying trough. Above the powder-laying trough, the frame is provided with a horizontally movable stamping mechanism and a light-transmitting powder blocking mechanism. The light-transmitting powder blocking mechanism is used to block the notch at the top of the powder-laying trough to allow the powder bed lifting mechanism to lift and press the powder. The laser sintering mechanism is used to sinter the powder on the powder bed lifting mechanism into a solid body. The powder bed lifting mechanism is provided with a forming trough, a forming table adapted to the forming trough is provided in the forming trough, and a first lifting drive member for driving the forming table to lift and lower is provided below the forming table in the forming trough. A powder-laying laser additive forming method is also disclosed, comprising the steps of: determining the thickness of the powder; spreading the powder; pressing the powder; laser sintering; and stamping. The present powder-laying laser additive forming device and method can improve production efficiency and product quality, and can reduce powder waste and processing costs.

Description

Technical Field

[0001] The present invention relates to the technical field of laser additive manufacturing, and in particular to a powder-laying laser additive forming device and method. Background Art

[0002] The powder forming process generally uses laser additive manufacturing technology to stack powder layers to form a solid body, and then the solid body is stamped into shape.

[0003] Laser additive manufacturing (LAM) involves laying down the powder bed. A laser beam then melts or sinters the metal powder along a trajectory defined by a three-dimensional model, layer by layer, to form a solid. Laser additive manufacturing is unrestricted by part structure and is a key technology for addressing the difficulty in producing complex plates with biomimetic and three-dimensional structures.

[0004] Stamping is a process in which a press and die are used to apply external forces to sheets, strips, tubes, and profiles, causing them to deform or separate, thereby obtaining a workpiece (stamping) of the desired shape and size. Stampings are lightweight, thin, and rigid. Their dimensional tolerances are determined by the die, resulting in consistent quality and generally requiring no further mechanical cutting.

[0005] Existing laser additive manufacturing equipment has the following defects:

[0006] (1) Long processing time and low production efficiency;

[0007] (2) The equipment processing is complex, and laser sintering and stamping cannot be completed simultaneously on the same processing table;

[0008] (3) The actual processing area is 50-70%. If it is not recycled, a large amount of unprocessed powder will be wasted;

[0009] (4) There are a large number of voids in the powder material. After laser sintering, the formed layer will shrink severely, resulting in the inability to perfectly match the parameters of the next layer. Eventually, defects continue to accumulate, and the dimensional accuracy of the formed part does not meet the requirements, which seriously affects the density of the workpiece and ultimately reduces the service performance and life of the workpiece. Summary of the Invention

[0010] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a powder-laying laser additive manufacturing device and method that can improve production efficiency and product quality and reduce powder waste and processing costs.

[0011] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0012] A powder-laying laser additive forming device comprises a laser sintering mechanism, a frame and a powder-laying trough provided at the lower part of the frame with the notch facing upwards, a lifting powder bed mechanism for placing powder and being able to be lifted and lowered is provided in the powder-laying trough, the frame is provided with a stamping mechanism and a light-transmitting powder blocking mechanism both of which can be moved horizontally above the powder-laying trough, the light-transmitting powder blocking mechanism is used to seal the notch at the top of the powder-laying trough for the lifting powder bed mechanism to lift and press the powder, the laser sintering mechanism is used to emit a laser above the light-transmitting powder blocking mechanism to sinter the powder on the lifting powder bed mechanism into a solid, the stamping mechanism is used to stamp and form the solid sintered on the lifting powder bed mechanism, the lifting powder bed mechanism is provided with a forming groove adapted to the stamping mechanism, a forming table adapted to the forming groove is provided in the forming groove, and a first lifting drive component for driving the forming table to lift and lower is provided below the forming table.

[0013] As a further improvement of the above technical solution:

[0014] The powder bed lifting mechanism includes a powder bed placed in and adapted to the powder laying trough and a second lifting drive member provided below the powder bed for driving the powder bed to lift. The forming trough is provided on the powder bed.

[0015] The light-transmitting powder-blocking mechanism comprises a horizontal light-transmitting plate and a first horizontal driving component arranged on a frame and used for driving the light-transmitting plate to move horizontally.

[0016] The first horizontal drive assembly includes two parallel first screw rods and first screw sleeves respectively arranged on both sides of the light-transmitting plate. The first screw rods are rotatably arranged on the frame. The first screw sleeves are respectively sleeved on each first screw rod. The frame is provided with a first rotation drive assembly for driving each first screw rod to rotate synchronously.

[0017] The stamping mechanism includes a translation frame arranged on the frame and a second translation drive assembly for driving the translation frame to translate. The translation frame is provided with a stamping die and a third lifting drive component for driving the stamping die to rise and fall. The stamping die is provided with a heating element.

[0018] The second translation drive assembly includes two parallel second screw rods and second screw sleeves respectively arranged on both sides of the translation frame. The second screw rods are rotatably set on the frame, and the second screw sleeves are respectively sleeved on each second screw rod. The frame is provided with a second rotation drive assembly for driving each second screw rod to rotate synchronously.

[0019] The punching mechanism and the light-transmitting powder-blocking mechanism are arranged alternately up and down.

[0020] The light-transmitting powder blocking mechanism is located below the punching mechanism.

[0021] A powder spreading laser additive forming method is performed using the above-mentioned powder spreading laser additive forming device, comprising the following steps:

[0022] S1. Determine the powder spreading thickness: The powder bed lifting mechanism is raised and lowered so that the top surface of the powder bed lifting mechanism is at a predetermined height from the top surface of the powder spreading trough to determine the powder spreading thickness;

[0023] S2, powder spreading: spreading a layer of mixed powder on the lifting powder bed mechanism;

[0024] S3, Powder Compacting: The light-transmitting powder blocking mechanism moves horizontally to block the notch at the top of the powder trough, and the powder bed lifting mechanism rises to compact the powder on it;

[0025] S4, laser sintering: The laser sintering mechanism emits laser light above the light-transmitting powder blocking mechanism, and the laser light passes through the light-transmitting powder blocking mechanism to sinter the powder on the lifting powder bed mechanism into a solid body;

[0026] S5. Stamping: remove the light-transmitting powder blocking mechanism from the slot at the top of the powder spreading trough; move the stamping mechanism horizontally to the top of the powder spreading trough and align it with the forming trough; the first lifting drive member drives the forming table to descend a predetermined distance; then, the stamping mechanism presses down to form the part of the sintered entity corresponding to the forming trough.

[0027] Compared with the prior art, the advantages of the present invention are:

[0028] The powder-spreading laser additive manufacturing device of the present invention integrates powder spreading, powder compacting, and stamping into a single device, shortening processing time and improving production efficiency. Laser sintering of the powder after compaction results in high dimensional accuracy, density, and quality of the finished workpiece. Powder spreading is performed on a lifting powder bed mechanism within the powder-spreading trough, minimizing powder waste. This device has a rational structural design and can improve production efficiency, powder spreading uniformity, and product quality, while reducing powder waste and processing costs.

[0029] The powder-laying laser additive manufacturing method of the present invention integrates powder laying, powder compacting, and stamping into a single device, shortening processing time and improving production efficiency. Laser sintering of the powder after compaction results in high dimensional accuracy, density, and quality of the finished workpiece. Powder laying is performed on a lifting powder bed mechanism within the powder-laying trough, minimizing powder waste. This powder-laying laser additive manufacturing method can improve production efficiency, powder-laying uniformity, and product quality, while reducing powder waste and processing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the three-dimensional structure of the powder-laying laser additive forming device of the present invention from a first perspective.

[0031] Figure 2 It is a schematic diagram of the three-dimensional structure of the powder-laying laser additive manufacturing device of the present invention from a second viewing angle.

[0032] Figure 3It is a schematic diagram of the main structure of the powder-laying laser additive forming device of the present invention.

[0033] Figure 4 It is a schematic diagram of the main cross-sectional structure of the powder-laying laser additive forming device of the present invention.

[0034] Figure 5 yes Figure 4 Enlarged view of point A in the middle.

[0035] Figure 6 yes Figure 4 Enlarged view of point B in the middle.

[0036] Figure 7 It is a structural schematic diagram of the stamping mechanism of the powder mixing-material adding-stamping composite forming device of the present invention.

[0037] Figure 8 It is a structural schematic diagram of the lifting powder bed mechanism of the powder mixing-additive-stamping composite forming device of the present invention.

[0038] The numbers in the figure represent:

[0039] 1. Frame; 2. Powder spreading trough; 3. Stamping mechanism; 31. Translation frame; 32. Stamping die; 321. Stamping part; 33. Third lifting drive member; 34. Heating element; 35. Second screw rod; 36. Second screw sleeve; 37. Second rotary drive assembly; 4. Lifting powder bed mechanism; 41. Powder bed; 42. Second lifting drive member; 43. Forming trough; 44. Forming table; 45. First lifting drive member; 5. Transparent powder blocking mechanism; 51. First screw sleeve; 52. Transparent plate; 53. First screw rod; 54. First rotary drive assembly. DETAILED DESCRIPTION

[0040] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0041] As shown in this disclosure and the claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not specifically refer to the singular, but also include the plural. The words "first", "second" and similar words used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect.

[0042] Example 1:

[0043] Figures 1 to 8An embodiment of the powder-laying laser additive forming device of the present invention is shown. The powder-laying laser additive forming device includes a laser sintering mechanism, a frame 1 and a powder-laying trough 2 provided at the lower part of the frame 1 with the notch facing upward. A lifting powder bed mechanism 4 for placing powder and being able to lift and lower is provided in the powder-laying trough 2. The frame 1 is provided with a stamping mechanism 3 and a light-transmitting powder blocking mechanism 5 both of which can be moved horizontally above the powder-laying trough 2. The light-transmitting powder blocking mechanism 5 is used to seal the notch at the top of the powder-laying trough 2 for the lifting powder bed mechanism 4 to lift the pressurized powder. The laser sintering mechanism is used to emit a laser above the light-transmitting powder blocking mechanism 5 to sinter the powder on the lifting powder bed mechanism 4 into a solid. The stamping mechanism 3 is used to stamp the solid sintered on the lifting powder bed mechanism 4. The lifting powder bed mechanism 4 is provided with a forming groove 43 adapted to the stamping mechanism 3. A forming table 44 adapted to the forming groove 43 is provided in the forming groove 43. The forming groove 43 is provided with a first lifting drive member 45 below the forming table 44 for driving the forming table 44 to lift and lower.

[0044] The processing process of the powder-laying laser additive forming device is as follows: the first step is to raise and lower the powder bed lifting mechanism 4 so that the top surface of the powder bed lifting mechanism 4 is at a predetermined height from the top surface of the powder laying trough 2 to determine the powder laying thickness; the second step is to lay a layer of mixed powder on the powder bed lifting mechanism 4; the third step is to translate the light-transmitting powder blocking mechanism 5 to the slot blocking the top of the powder laying trough 2, and the powder bed lifting mechanism 4 rises to compact the powder thereon; the fourth step is to emit a laser above the light-transmitting powder blocking mechanism 5, and the laser passes through the light-transmitting powder blocking mechanism 5 to sinter the powder on the powder bed lifting mechanism 4 into a solid; the fifth step is to remove the light-transmitting powder blocking mechanism 5 from the slot at the top of the powder laying trough 2; the stamping mechanism 3 is translated to the top of the powder laying trough 2 and aligned with the forming slot 43 up and down; the first lifting drive member 45 drives the forming table 44 to descend a predetermined distance; then, the stamping mechanism 3 presses down to press the sintered solid and the part corresponding to the forming slot 43 into shape. This powder-spreading laser additive manufacturing device integrates powder spreading, powder compacting, and stamping into a single device, shortening processing time and improving production efficiency. Laser sintering is performed after powder compaction, resulting in high-quality workpieces with high dimensional accuracy and density. Powder spreading is performed on a powder bed lifting mechanism 4 within a powder spreading trough 2, minimizing powder waste. This device boasts a rational structural design, improving production efficiency and product quality while reducing powder waste and processing costs.

[0045] In this embodiment, Figure 5As shown, the powder bed lifting mechanism 4 includes a powder bed 41 placed within and compatible with the powder spreading trough 2, a second lifting drive 42 positioned below the powder bed 41 for driving the powder bed 41 upward and downward, and a forming trough 43 positioned above the powder bed 41. Specifically, the perimeter of the powder bed 41 conforms to the inner wall of the powder spreading trough 2, preventing a large gap from forming between the powder bed 41 and the inner wall of the powder spreading trough 2, which could cause powder to fall. Similarly, the perimeter of the forming table 44 conforms to the inner wall of the forming trough 43, preventing a large gap from forming between the forming table 44 and the inner wall of the forming trough 43, which could cause powder to fall. The top surfaces of the powder bed 41 and the forming table 44 are both horizontal, with the opening of the forming trough 43 facing upward. The opposite surface of the light-transmitting powder-blocking mechanism 5 and the powder bed 41 is also flat. When spreading the powder, the first lifting drive member 45 makes the forming table 44 flush with the top surface of the powder bed 41. In this way, the powder can be compacted and flattened in the powder bed 41 and the light-transmitting powder-blocking mechanism 5.

[0046] In this embodiment, Figure 6 As shown, the light-transmitting powder blocking mechanism 5 includes a horizontal light-transmitting plate 52 and a first horizontal driving assembly provided on the frame 1 for driving the light-transmitting plate 52 to move horizontally. When pressing powder, the first horizontal driving assembly causes the light-transmitting plate 52 to move horizontally to block the notch at the top of the powder spreading trough 2. The bottom surface of the light-transmitting plate 52 is flush with the top surface of the powder spreading trough 2, or is spaced a proper distance from the top surface of the powder spreading trough 2. This distance prevents powder from passing through the gap between the light-transmitting plate 52 and the top surface of the powder spreading trough 2 when the light-transmitting plate 52 blocks the notch at the top of the powder spreading trough 2. The area of ​​the light-transmitting plate 52 is larger than the notch of the powder spreading trough 2.

[0047] In this embodiment, Figure 1 and Figure 3 As shown, the first horizontal drive assembly includes two parallel first screw rods 53 and first screw sleeves 51 respectively arranged on both sides of the light-transmitting plate 52. The first screw rods 53 are rotatably mounted on the frame 1, and the first screw sleeves 51 are respectively sleeved on each first screw rod 53. The frame 1 is provided with a first rotary drive assembly 54 for driving the first screw rods 53 to rotate synchronously. The first screw sleeves 51 are fixedly connected to the light-transmitting plate 52 and are located above the light-transmitting plate 52. The first rotary drive assembly 54 drives the first screw rods 53 to rotate synchronously, driving the first screw sleeves 51 and the light-transmitting plate 52 to move horizontally. The structure is simple and easy to operate.

[0048] In this embodiment, Figures 1 to 4 As shown, the stamping mechanism 3 includes a translation frame 31 mounted on the frame 1 and a second translation drive assembly for driving the translation frame 31 to translate. The translation frame 31 is provided with a stamping die 32 and a third lifting drive member 33 for driving the stamping die 32 to move upward and downward. The stamping die 32 is provided with a heating element 34. The second translation drive assembly drives the translation frame 31 to translate, causing the stamping die 32 to translate between directly above and laterally above the powder spreading trough 2.

[0049] In this embodiment, the second translation drive assembly includes two parallel second screw rods 35 and second screw sleeves 36 respectively arranged on both sides of the translation frame 31. The second screw rods 35 are rotatably arranged on the frame 1, and the second screw sleeves 36 are respectively sleeved on each second screw rod 35. The frame 1 is provided with a second rotation drive assembly 37 for driving each second screw rod 35 to rotate synchronously. The second screw sleeve 36 is fixedly connected to the translation frame 31 and is located above the translation frame 31. The second rotation drive assembly 37 drives each second screw rod 35 to rotate synchronously, driving the second screw sleeve 36 and the translation frame 31 to move horizontally. The structure is simple and easy to operate. The bottom of the stamping die 32 is provided with a downwardly convex stamping portion 321, which is adapted to the shape of the forming groove 43 and the forming table 44.

[0050] In this embodiment, the punching mechanism 3 and the light-transmitting powder blocking mechanism 5 are staggered vertically to avoid motion interference. Specifically, the punching mechanism 3 is located above the light-transmitting powder blocking mechanism 5. The screws are arranged horizontally and parallel. A vibration mechanism can be installed on the powder spreading box 61 to prevent powder residue in the powder spreading box 61.

[0051] Example 2:

[0052] A powder-spreading laser additive forming method is performed using the powder-spreading laser additive forming device of Example 1, comprising the following steps:

[0053] S1. Determine the powder spreading thickness: The powder bed lifting mechanism 4 is raised and lowered so that the top surface of the powder bed lifting mechanism 4 is at a predetermined height from the top surface of the powder spreading trough 2 to determine the powder spreading thickness;

[0054] S2, powder spreading: spreading a layer of mixed powder on the powder bed lifting mechanism 4;

[0055] S3, powder compaction: the light-transmitting powder blocking mechanism 5 moves horizontally to block the notch at the top of the powder laying trough 2, and the powder bed lifting mechanism 4 rises to compact the powder thereon;

[0056] S4, laser sintering: the laser sintering mechanism emits laser light above the light-transmitting powder blocking mechanism 5, and the laser light passes through the light-transmitting powder blocking mechanism 5 to sinter the powder on the lifting powder bed mechanism 4 into a solid body;

[0057] S5. Stamping and forming: remove the light-transmitting powder blocking mechanism 5 from the slot at the top of the powder spreading trough 2; move the stamping mechanism 3 horizontally to the top of the powder spreading trough 2, and align it with the forming groove 43; the first lifting drive member 45 drives the forming table 44 to descend a predetermined distance; then, the stamping mechanism 3 presses down to form the part of the sintered entity corresponding to the forming groove 43.

[0058] This powder-spreading laser additive manufacturing method integrates powder spreading, powder compacting, and stamping into a single device, shortening processing time and improving production efficiency. Laser sintering is performed after powder compaction, resulting in high-quality workpieces with high dimensional accuracy and density. Powder spreading is performed on a powder bed lifting mechanism 4 within a powder spreading trough 2, minimizing powder waste. This powder-spreading laser additive manufacturing method can improve production efficiency and product quality while reducing powder waste and processing costs.

[0059] Although the present invention has been disclosed above with reference to preferred embodiments, this is not intended to limit the present invention. Any person skilled in the art can, without departing from the scope of the technical solution of the present invention, utilize the technical content disclosed above to make many possible changes and modifications to the technical solution of the present invention, or modify it into an equivalent embodiment with equivalent changes. Therefore, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the scope of protection of the technical solution of the present invention.

Claims

1. A powder-laying laser additive manufacturing device, characterized by: The invention comprises a laser sintering mechanism, a frame (1) and a powder spreading trough (2) provided at the bottom of the frame (1) with the notch facing upwards, wherein a lifting powder bed mechanism (4) for placing powder and capable of lifting and lowering is provided in the powder spreading trough (2), and the frame (1) is provided with a punching mechanism (3) and a light-transmitting powder blocking mechanism (5) both of which are horizontally movable above the powder spreading trough (2), wherein the light-transmitting powder blocking mechanism (5) is used to block the notch at the top of the powder spreading trough (2) so that the lifting powder bed mechanism (4) can lift and press the powder, and the laser sintering mechanism is used to emit a laser above the light-transmitting powder blocking mechanism (5) to sinter the powder on the lifting powder bed mechanism (4) into a solid body, and the punching mechanism (3) is used to press the lifting powder bed mechanism (4) The solid body sintered on the powder bed is formed by stamping, the powder bed lifting mechanism (4) is provided with a forming groove (43) adapted to the stamping mechanism (3), the forming groove (43) is provided with a forming table (44) adapted to the forming groove (43), and the forming groove (43) is provided with a first lifting driving member (45) for driving the forming table (44) to lift and lower below the forming table (44); the powder bed lifting mechanism (4) includes a powder bed (41) placed in the powder laying groove (2) and adapted to the powder laying groove (2) and a second lifting driving member (42) provided below the powder bed (41) for driving the powder bed (41) to lift and lower, and the forming groove (43) is provided on the powder bed (41); The light-transmitting powder blocking mechanism (5) comprises a horizontal light-transmitting plate (52) and a first horizontal driving assembly provided on the frame (1) for driving the light-transmitting plate (52) to move horizontally; the stamping mechanism (3) comprises a translation frame (31) provided on the frame (1) and a second translation driving assembly for driving the translation frame (31) to move horizontally; the translation frame (31) is provided with a stamping die (32) and a third lifting driving member (33) for driving the stamping die (32) to move up and down; the stamping die (32) is provided with a heating member (34); the stamping mechanism (3) and the light-transmitting powder blocking mechanism (5) are arranged in an upper and lower staggered manner; the light-transmitting powder blocking mechanism (5) is located below the stamping mechanism (3).

2. The powder-laying laser additive manufacturing device according to claim 1, characterized in that: The first horizontal drive assembly comprises two parallel first screw rods (53) and first screw sleeves (51) respectively arranged on both sides of the light-transmitting plate (52); the first screw rods (53) are rotatably arranged on the frame (1); the first screw sleeves (51) are respectively sleeved on each first screw rod (53); and the frame (1) is provided with a first rotation drive assembly (54) for driving each first screw rod (53) to rotate synchronously.

3. The powder-laying laser additive manufacturing device according to claim 1 or 2, characterized in that: The second translation drive assembly comprises two parallel second screw rods (35) and second screw sleeves (36) respectively arranged on both sides of the translation frame (31); the second screw rods (35) are rotatably arranged on the frame (1); the second screw sleeves (36) are respectively sleeved on each second screw rod (35); and a second rotation drive assembly (37) for driving each second screw rod (35) to rotate synchronously is provided on the frame (1).

4. A powder-laying laser additive manufacturing method, characterized in that: The method is carried out using the powder-laying laser additive forming device according to any one of claims 1 to 3, comprising the following steps: S1. Determine the powder spreading thickness: the powder bed lifting mechanism (4) is raised and lowered so that the top surface of the powder bed lifting mechanism (4) is at a predetermined height from the top surface of the powder spreading trough (2) to determine the powder spreading thickness; S2, spreading powder: spreading a layer of mixed powder on the lifting powder bed mechanism (4); S3, powder pressing: the light-transmitting powder blocking mechanism (5) moves horizontally to the slot blocking the top of the powder laying trough (2), and the powder bed lifting mechanism (4) rises to compact the powder on it; S4, laser sintering: the laser sintering mechanism emits laser light above the light-transmitting powder blocking mechanism (5), and the laser light passes through the light-transmitting powder blocking mechanism (5) to sinter the powder on the lifting powder bed mechanism (4) into a solid body; S5, stamping and forming: the light-transmitting powder blocking mechanism (5) is removed from the notch at the top of the powder spreading trough (2); the stamping mechanism (3) is moved horizontally to the top of the powder spreading trough (2) and aligned with the forming trough (43) vertically; the first lifting drive member (45) drives the forming table (44) to descend a predetermined distance; then, the stamping mechanism (3) presses down to form the portion of the sintered solid corresponding to the forming trough (43).

Images