A substrate disassembly method suitable for a powder bed additive manufacturing process

By using internal stress reduction tooling and four corner force transmission supports, the problem of difficult substrate disassembly caused by internal stress in powder bed additive manufacturing was solved, enabling smooth substrate disassembly and ensuring part quality.

CN116673494BActive Publication Date: 2026-06-02WUHU STATE-OWNED FACTORY OF MACHINING
View PDF 2 Cites 0 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
WUHU STATE-OWNED FACTORY OF MACHINING
Filing Date
2023-05-29
Publication Date
2026-06-02

AI Technical Summary

Technical Problem

In powder bed additive manufacturing, the internal stress caused by the formed parts makes it difficult to turn the hex socket screws, resulting in difficulties in disassembling the substrate, which usually requires destructive methods.

Method used

By employing an internal stress reduction fixture and four corner force transmission supports, the internal stress is offset by elastic deformation. The screws are then removed using an Allen wrench. The four legs of the internal stress reduction fixture offset the internal stress of the parts on the substrate. The screws are then removed using an Allen wrench.

Benefits of technology

It effectively reduces the resistance of removing the hexagonal screws at the four corners of the fixed substrate, ensuring smooth disassembly of the substrate, and the four corner force transmission supports are used for structural and stress analysis to ensure the quality of the parts.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure CN116673494B_ABST
    Figure CN116673494B_ABST
Patent Text Reader

Abstract

This invention relates to the field of powder bed additive manufacturing technology, specifically to a substrate disassembly method suitable for powder bed additive manufacturing processes. The method includes: (i) constructing a model of the part to be formed and a model of the four corner force transmission supports, and importing them into an additive manufacturing device to complete additive printing on the substrate; (ii) fabricating an internal stress relief fixture; (iii) positioning the four legs of the internal stress relief fixture against the four corner force transmission supports from the inside out; (iv) rotating the bolts with a wrench, causing the ends of the bolts to press against the left support, moving the left support 6 to the left and the right support to the right; and (v) using an Allen wrench to remove the Allen screws fixed at the four corners of the substrate. This invention, through the internal stress relief fixture and the four corner force transmission supports formed synchronously with the part, generates outward stress through elastic deformation to counteract the inward internal stress on the substrate caused by the formed part, thereby greatly reducing the resistance to removing the Allen screws fixing the four corners of the substrate.
Need to check novelty before this filing date? Find Prior Art

Description

Technical Field

[0001] This invention relates to the field of powder bed additive manufacturing technology, specifically to a substrate disassembly method applicable to powder bed additive manufacturing processes. Background Technology

[0002] pink Last-bed additive manufacturing technology uses a small-diameter laser spot or electron beam to melt thin layers of powder, depositing them layer by layer to form parts. It is suitable for manufacturing relatively complex parts. During the forming process, the substrate provides the adhesion surface for the first layer of powder, ensuring the shape stability of the workpiece during printing. Furthermore, the substrate has good thermal conductivity relative to the powder, keeping the cooling rate consistently high during additive manufacturing, resulting in a fast-cooling microstructure with good performance. During the additive manufacturing process, the powder is heated and melted by a high-energy heat source to form tiny molten pools, which then rapidly solidify. During the transition from liquid to solid phase, the hindered solidification shrinkage generates significant internal stress. After printing, the internal stress caused by the formed part is transferred to the substrate, causing the hexagonal screws securing the substrate to become overtightened and difficult to loosen. Excessive internal stress also causes the hexagonal screws to strip during disassembly, requiring destructive methods to remove the substrate's fixing screws. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention proposes a substrate disassembly method suitable for powder bed additive manufacturing processes.

[0004] The technical problem to be solved by this invention is achieved by the following technical solution:

[0005] A substrate removal method suitable for powder bed additive manufacturing process includes the following steps:

[0006] Step (1) Construct the part model to be formed and the four corner force transmission pillar model. The four corner force transmission pillar model is distributed around the part model. Import it into the additive manufacturing equipment to complete the additive printing on the substrate.

[0007] Step (2) Fabricate internal stress relief fixture, which includes a left support, a right support, and bolts set on the right support with their ends abutting against the left support.

[0008] Step (3) Place the internal stress relief device on the substrate and have the four legs of the internal stress relief device abut against the four corner force transmission pillars from the inside out.

[0009] Step (4) Rotate the bolt with a wrench. The end of the bolt presses against the left bracket, causing the left bracket 6 to move to the left and the right bracket to move to the right. The outward pushing force is transmitted to the four corner force transmission pillars through the support legs to counteract the internal stress of the parts on the substrate.

[0010] Step (5) Use an Allen wrench to remove the Allen screws fixed at the four corners of the base plate;

[0011] Step (6) After removing the substrate, use wire cutting to cut out the required parts and the four corner force transmission supports.

[0012] Preferably, the four corner force transmission supports formed in step (i) include a first force transmission support located at the upper left of the formed part, a second force transmission support located at the lower left of the formed part, a third force transmission support located at the upper right of the formed part, and a fourth force transmission support located at the lower right of the formed part. The two legs of the left support abut against the first force transmission support and the second force transmission support, and the two legs of the right support abut against the third force transmission support and the fourth force transmission support.

[0013] Preferably, all four force transmission supports are cuboids and their height does not exceed the maximum height of the formed part. The top surface of each of the four force transmission supports is a square, and the side length of the square is 1 cm.

[0014] Preferably, the angle between the lower right side of the first force transmission support and the upper surface of the substrate is 45°, and the center of the first force transmission support is 3cm from the left side of the substrate and 3cm from the upper side of the substrate.

[0015] Preferably, the angle between the upper right side of the second force transmission support and the upper surface of the substrate is 45°, and the center of the second force transmission support is 3cm from the left side of the substrate and 3cm from the lower side of the substrate.

[0016] Preferably, the lower left side of the third force transmission support forms an angle of 45° with the upper surface of the substrate, and the center of the third force transmission support is 3cm from the right side of the substrate and 3cm from the upper side of the substrate.

[0017] Preferably, the angle between the upper left side of the fourth force transmission support and the upper surface of the substrate is 45°, and the center of the fourth force transmission support is 3cm from the right side of the substrate and 3cm from the lower side of the substrate.

[0018] Preferably, the left support includes an upper left L-shaped support leg that matches and abuts against the first force transmission column, and a lower left L-shaped support leg that matches and abuts against the second force transmission column. A round hole, an upper positioning square hole, and a lower positioning square hole are provided in the middle of the right side of the left support frame.

[0019] Preferably, the right support includes an upper right L-shaped support leg that matches and abuts against the third force transmission support, and a lower right L-shaped support leg that matches and abuts against the fourth force transmission support. The left side of the right support frame is provided with an upper positioning protrusion and a lower positioning protrusion corresponding to the positions of the upper positioning square hole and the lower positioning square hole. The middle part of the right support frame is provided with a threaded hole corresponding to the position of the round hole, and bolts are connected in the threaded hole and the round hole.

[0020] Preferably, the bolt includes a cylindrical section located inside the circular hole with its end face abutting against the inner wall of the circular hole, a threaded section threadedly connected to the threaded hole, and a hexagonal prism section located outside the threaded hole.

[0021] The beneficial effects of this invention are:

[0022] This invention utilizes an internal stress reduction fixture in conjunction with four corner force transmission supports that are formed synchronously with the part. Through elastic deformation, outward stress is generated to counteract the inward internal stress on the substrate caused by the formed part, thereby greatly reducing the resistance to removing the hexagonal screws fixing the four corners of the substrate. The four legs of the internal stress reduction fixture are all L-shaped, which provides a good positioning effect. The four corner force transmission supports can also be used for tissue and stress analysis to ensure the quality of the printed parts. Attached Figure Description

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0024] Figure 1 A three-dimensional structural diagram of the formed parts and the four corner force transmission pillars on the substrate;

[0025] Figure 2 A top view schematic diagram of the formed parts and the four corner force transmission pillars on the substrate;

[0026] Figure 3 This is a three-dimensional structural schematic diagram of the internal stress reduction fixture;

[0027] Figure 4 This is a three-dimensional structural diagram of the left support in the internal stress reduction fixture;

[0028] Figure 5 This is a three-dimensional structural diagram of the right support in the internal stress reduction fixture;

[0029] Figure 6 A three-dimensional structural diagram of the bolt in the internal stress relief fixture;

[0030] Figure 7 This is a schematic diagram of the internal stress reduction tooling.

[0031] In the diagram: 1. First force transmission support; 2. Second force transmission support; 3. Third force transmission support; 4. Fourth force transmission support; 5. Part; 6. Left bracket; 7. Right bracket; 8. Bolt; 9. Upper left L-shaped support; 10. Lower left L-shaped support; 11. Upper positioning square hole; 12. Lower positioning square hole; 13. Round hole; 14. Upper right L-shaped support; 15. Lower right L-shaped support; 16. Upper positioning protrusion; 17. Lower positioning protrusion; 18. Threaded hole; 19. Cylindrical section; 20. Threaded section; 21. Hexagonal prism section; 22. Base plate. Detailed Implementation

[0032] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0033] A substrate removal method suitable for powder bed additive manufacturing process includes the following steps:

[0034] Step (1) Construct the part model to be formed and the four corner force transmission support model. The four corner force transmission support models are distributed around the part model. Import the model into the additive manufacturing equipment to complete the additive printing on the substrate 22. The printed part 5 and the four corner force transmission supports are as follows: Figure 1 and Figure 2 As shown.

[0035] The component 5 is located in the middle of the substrate 22; the four corner force transmission pillars include a first force transmission pillar 1, a second force transmission pillar 2, a third force transmission pillar 3, and a fourth force transmission pillar 4; the first force transmission pillar 1 is located on the upper left side of the substrate 22, the second force transmission pillar 2 is located on the lower left side of the substrate 22, the third force transmission pillar 3 is located on the upper right side of the substrate 22, and the fourth force transmission pillar 4 is located on the lower right side of the substrate 22; all four force transmission pillars are cuboids and their height is not higher than the maximum height of the formed component 5, and the top surface of each of the four force transmission pillars is a square with a side length of 1 cm.

[0036] Furthermore, the lower right side of the first force transmission support 1 forms an angle of 45° with the upper surface of the substrate, and the center of the first force transmission support 1 is 3cm from the left side of the substrate 22 and 3cm from the upper side of the substrate 22.

[0037] The upper right side of the second force transmission support 2 forms an angle of 45° with the upper surface of the substrate. The center of the second force transmission support 2 is 3cm from the left side of the substrate 22 and 3cm from the lower side of the substrate 22.

[0038] The lower left side of the third force transmission support 3 forms an angle of 45° with the upper surface of the substrate. The center of the third force transmission support 3 is 3cm away from the right side of the substrate 22 and 3cm away from the upper side of the substrate 22.

[0039] The angle between the upper left side of the fourth force transmission support 4 and the upper surface of the substrate is 45°. The center of the fourth force transmission support 4 is 3cm from the right side of the substrate 22 and 3cm from the lower side of the substrate 22.

[0040] Step (II) Fabricate the internal stress reduction fixture, which mainly includes the left support 6, the right support 7, and the bolts 8. For example... Figure 3 As shown, the left bracket 6 and the right bracket 7 are combined together, and the bolt 8 is connected to the left bracket 6 and the right bracket 7.

[0041] Furthermore, such as Figure 4As shown, the left support 6 includes an upper left L-shaped support leg 9 that matches and abuts against the first force transmission support 1, and a lower left L-shaped support leg 10 that matches and abuts against the second force transmission support 2. A round hole 13, an upper positioning square hole 11, and a lower positioning square hole 12 are provided in the middle of the right side of the frame of the left support 6.

[0042] like Figure 5 As shown, the right support 7 includes an upper right L-shaped support leg 14 that matches and abuts against the third force transmission support 3 and a lower right L-shaped support leg 15 that matches and abuts against the fourth force transmission support 4. The left side of the frame of the right support 7 is provided with an upper positioning protrusion 16 and a lower positioning protrusion 17 corresponding to the positions of the upper positioning square hole 11 and the lower positioning square hole 12. The middle part of the frame of the right support 7 is provided with a threaded hole 18 corresponding to the position of the round hole 13. The bolt 8 is connected in the threaded hole 18 and the round hole 13.

[0043] like Figure 6 As shown, the bolt 8 includes a cylindrical section 19 located inside the circular hole 13 and whose end face abuts against the inner wall of the circular hole 13, a threaded section 20 threadedly connected to the threaded hole 18, and a hexagonal prism section 21 located outside the threaded hole 18.

[0044] By inserting the upper positioning protrusion 16 and the lower positioning protrusion 17 of the right bracket 7 into the upper positioning square hole 11 and the lower positioning square hole 12 of the left bracket 6 respectively, the left bracket 6 and the right bracket 7 are combined into a whole.

[0045] Step (3) Place the internal stress relief device on the base plate 22, and place the four legs of the internal stress relief device against the four corner force transmission pillars from the inside to the outside.

[0046] Step (four): Screw bolt 8 into the threaded hole 18 of the right bracket 7 and the round hole 13 of the left bracket 6. Rotate the hexagonal prism section 21 of bolt 8 with a wrench, so that the bottom surface of the cylindrical section 19 of bolt 8 presses against the bottom surface of the round hole 13 of the left bracket 6, thereby causing the left bracket 6 to move to the left and the right bracket 7 to move to the right. This causes the upper left L-shaped support 9 to transmit the force in the upper left direction to the first force transmission support 1, the lower left L-shaped support 10 to transmit the force in the lower left direction to the second force transmission support 2, the upper right L-shaped support 14 to transmit the force in the upper right direction to the third force transmission support 3, and the lower right L-shaped support 15 to transmit the force in the lower right direction to the fourth force transmission support 4, so as to counteract the internal stress of component 5 on substrate 22. The working state is as follows. Figure 7 As shown.

[0047] Step (5) Use an Allen wrench to remove the Allen screws fixed at the four corners of the base plate 22.

[0048] Step (six): After removing the substrate 22, the required parts 5 and the four corner force transmission supports are cut off by wire cutting. Furthermore, the cut-off four corner force transmission supports can be used for corresponding microstructure and stress analysis to ensure the quality of the formed parts 5.

[0049] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely prisms of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for disassembling a substrate suitable for powder bed additive manufacturing process, characterized in that: Includes the following steps: Step (1) Construct the part model to be formed and the four corner force transmission pillar model. The four corner force transmission pillar model is distributed around the part model. Import it into the additive manufacturing equipment to complete the additive printing on the substrate (22). The four corner force transmission pillars formed in step (1) include the first force transmission pillar (1) located on the upper left of the formed part (5), the second force transmission pillar (2) located on the lower left of the formed part (5), the third force transmission pillar (3) located on the upper right of the formed part (5), and the fourth force transmission pillar (4) located on the lower right of the formed part (5). The two legs of the left support (6) abut against the first force transmission pillar (1) and the second force transmission pillar (2), and the two legs of the right support (7) abut against the third force transmission pillar (3) and the fourth force transmission pillar (4). Step (2) Make an internal stress relief fixture. The internal stress relief fixture includes a left support (6) and a right support (7) assembled together, and a bolt (8) set on the right support (7) with its end abutting against the left support (6). Step (3) Place the internal stress relief device on the substrate (22) and place the four legs of the internal stress relief device against the four corner force transmission pillars from the inside to the outside. Step (4) Rotate the bolt (8) with a wrench. The end of the bolt (8) presses against the left bracket (6), causing the left bracket (6) to move to the left and the right bracket (7) to move to the right. The outward pushing force is transmitted to the four corner force transmission pillars through the support legs to counteract the internal stress of the part (5) on the base plate (22). Step (5) Use an Allen wrench to remove the Allen screws fixed at the four corners of the base plate (22); After removing the substrate (22) in step (six), the required parts (5) and the four corner force transmission supports are cut off by wire cutting.

2. The substrate disassembly method applicable to powder bed additive manufacturing process according to claim 1, characterized in that: All four force transmission pillars are cuboids and their height is not higher than the maximum height of the formed part (5). The top surface of each of the four force transmission pillars is a square and the side length of the square is 1cm.

3. The substrate disassembly method applicable to powder bed additive manufacturing process according to claim 1, characterized in that: The lower right side of the first force transmission support (1) forms an angle of 45° with the upper surface of the substrate. The center of the first force transmission support (1) is 3cm from the left side of the substrate (22) and 3cm from the upper side of the substrate (22).

4. A substrate removal method suitable for powder bed additive manufacturing process according to claim 1, characterized in that: The upper right side of the second force transmission support (2) forms an angle of 45° with the upper surface of the substrate. The center of the second force transmission support (2) is 3cm from the left side of the substrate (22) and 3cm from the lower side of the substrate (22).

5. A substrate removal method suitable for powder bed additive manufacturing process according to claim 1, characterized in that: The lower left side of the third force transmission support (3) forms an angle of 45° with the upper surface of the substrate. The center of the third force transmission support (3) is 3cm away from the right side of the substrate (22) and 3cm away from the upper side of the substrate (22).

6. A substrate removal method suitable for powder bed additive manufacturing process according to claim 1, characterized in that: The angle between the upper left side of the fourth force transmission support (4) and the upper surface of the substrate is 45°. The center of the fourth force transmission support (4) is 3cm from the right side of the substrate (22) and 3cm from the lower side of the substrate (22).

7. A substrate removal method suitable for powder bed additive manufacturing process according to claim 1, characterized in that: The left support (6) includes an upper left L-shaped support (9) that matches and abuts against the first force transmission support (1) and a lower left L-shaped support (10) that matches and abuts against the second force transmission support (2). The left support (6) has a round hole (13) in the middle of the right side of the frame, an upper positioning square hole (11) and a lower positioning square hole (12) that are horizontally arranged alongside the round hole (13).

8. A substrate removal method suitable for powder bed additive manufacturing process according to claim 7, characterized in that: The right support (7) includes an upper right L-shaped support leg (14) that matches and abuts against the third force transmission support (3) and a lower right L-shaped support leg (15) that matches and abuts against the fourth force transmission support (4). The left side of the frame of the right support (7) is provided with an upper positioning protrusion (16) and a lower positioning protrusion (17) corresponding to the positions of the upper positioning square hole (11) and the lower positioning square hole (12). The middle part of the frame of the right support (7) is provided with a threaded hole (18) corresponding to the position of the round hole (13). The bolt (8) is connected in the threaded hole (18) and the round hole (13).

9. A substrate removal method suitable for powder bed additive manufacturing process according to claim 8, characterized in that: The bolt (8) includes a cylindrical section (19) located inside the round hole (13) and whose end face abuts against the inner wall of the round hole (13), a threaded section (20) threadedly connected to the threaded hole (18), and a hexagonal prism section (21) located outside the threaded hole (18).