Additive-equality-subtractive synchronous composite flexible double-point incremental forming equipment and method

Abstract

The invention relates to the field of machining and manufacturing of thin-wall parts, in particular to a flexible double-point incremental forming device and method for synchronously compounding material increase, equal material decrease, and the device comprises a master tool head, a slave tool head and a clamping device; a metal plate is clamped on the clamping device, and the main tool head and the auxiliary tool head are arranged on the two sides of the metal plate. The bottom face of the main tool head faces the metal plate. A runner for additive materials to pass through is arranged in the main tool head, and a runner outlet is formed in the bottom of the side wall face of the main tool head. The bottom of the tool head is provided with a cutting edge in the circumferential direction. Compared with the prior art, the problems that complex multi-metal heterogeneous thin-wall parts are difficult to prepare, and integration of composite plate preparation and part forming cannot be achieved are solved. According to the scheme, material increase-equal-decrease integrated machining of special high-performance thin-wall parts such as heterogeneous materials, variable thicknesses and surface textures is achieved, meanwhile, the defects of microcracks, delamination and the like of heterogeneous interfaces are overcome, and the product has enough connection strength and mechanical performance.

Description

Technical Field

[0001] This invention relates to the field of thin-walled part processing and manufacturing, specifically to a flexible two-point progressive forming equipment and method for simultaneous additive-equal-subtractive composite processing. Background Technology

[0002] In modern engineering applications, bimetallic or multimaterial structures are often required to meet reinforcement and specific needs. For example, bimetallic structures of stainless steel and aluminum alloys can achieve a good balance between high strength and lightweight; parts can be lightweighted and have improved heat dissipation by using localized areas composed of aluminum alloy, while stainless steel can provide the required strength and durability. However, the physical properties of dissimilar metals differ significantly, making it difficult to achieve high-quality welding while simultaneously performing forming processes.

[0003] To better form multi-metal thin-walled parts, Zhou et al. used laser welding to prepare steel-aluminum heterogeneous thin-walled parts in the paper "Effect of adding powder onjoint properties of laser penetration welding for dual phase steel and aluminum alloy" (Optics and Laser Technology, 2017, 94: 171-179), but the joint performance still needs further improvement. To improve the bonding strength of multi-metal interfaces, Chen et al. proposed a horizontal twin-roll casting process for composite plates in the paper "Bonding process and interfacial reaction in horizontal twin-roll casting of steel / aluminum clad sheet" (Journal of Materials Processing Technology, 2017, 246: 1-12), which improves the bonding performance of heterogeneous interfaces through a combination of rolling and casting.

[0004] In the prior art, for example, CN110369853A discloses a device and method for dual-point synchronous connection and progressive composite forming of laminated plates. The main purpose of this scheme is to achieve welding connection of dissimilar plates through friction welding while performing progressive forming. Similarly, CN109622755A discloses a composite forming device and method for dissimilar metal plate raw materials. The main purpose of this scheme is to achieve welding connection of dissimilar plates through friction welding and ultrasonic welding while performing progressive forming. However, these schemes all involve progressive forming and composite forming of plates with a certain thickness.

[0005] In the prior art, CN106311876A discloses a complex thin-walled part forming system and method based on incremental forming and additive manufacturing, which performs local material deposition through an added laser metal deposition system while incremental forming is being carried out; however, this solution directly adds a laser metal deposition system, resulting in a large space occupation and high structural complexity. Moreover, a single laser metal deposition system is prone to dead corners that are difficult to deposit during the incremental forming process due to obstruction and limitations on degrees of freedom and activity area, which ultimately leads to product defects.

[0006] While these methods are very inspiring, they are difficult to use for fabricating complex multi-metal heterogeneous thin-walled parts with varying thicknesses and special surface textures, and they cannot achieve integrated fabrication of composite plates and part forming, so production efficiency needs to be improved. Summary of the Invention

[0007] The purpose of this invention is to provide a flexible, two-point progressive forming device and method for simultaneous additive-subtractive processing to solve at least one of the aforementioned problems. This addresses the difficulty in fabricating complex multi-metal heterogeneous thin-walled parts and the inability to integrate composite plate fabrication with part forming in existing technologies. This solution achieves integrated additive-subtractive processing of special high-performance thin-walled parts with heterogeneous materials, varying thicknesses, and surface textures. Simultaneously, it eliminates defects such as delamination and microcracks at the heterogeneous interface during sequential joining-forming manufacturing, improves the collaborative deformation capability of heterogeneous thin-walled parts, and ensures that the processed products possess sufficient connection strength and mechanical properties.

[0008] The objective of this invention is achieved through the following technical solution: The first aspect of this invention discloses a flexible two-point progressive forming device for simultaneous additive-equal-subtractive material forming, used for progressive forming of metal sheets. The device includes a main tool head, a slave tool head, and a clamping device. The metal sheet is clamped on the clamping device, and the main tool head and the slave tool head are respectively disposed on both sides of the metal sheet; The bottom surface of the main tool head faces the metal sheet; the interior of the main tool head is provided with a channel for the flow of additive material, and the bottom of the side wall of the main tool head is provided with a channel outlet; the main tool head performs additive-equivalent forming on one side surface of the metal sheet; The tool head is positioned from the bottom surface toward the metal sheet; a cutting edge is provided circumferentially from the bottom of the tool head; and the tool head performs subtractive-equal material forming on the other side surface of the metal sheet.

[0009] Preferably, the top of the main tool head is provided with a wire feeding device; The aforementioned wire feeding device is disposed on the flow channel and is used to input additive material into the flow channel.

[0010] Preferably, a heating device is provided on the top of the main tool head; The heating device is installed on the flow channel and is used to heat and melt the additive material in the flow channel.

[0011] Preferably, both the main tool head and the slave tool head are flat-bottomed tool heads with a bottom radius of 1~5mm.

[0012] Preferably, the distance from the outlet of the flow channel to the bottom surface of the main tool head is 1~5mm.

[0013] Preferably, the helix angle of the cutting edge is 30~60°.

[0014] The second aspect of this invention discloses a flexible two-point progressive forming method for simultaneous additive-equal-subtractive composite material processing, which is performed using any of the equipment described above; The method includes the following steps: S1: Clean and dry the metal sheet, and clamp and fix the metal sheet onto the clamping device; S2: The main tool head and the slave tool head work together to apply a local downward pressure load to the metal sheet, causing the sheet to undergo plastic deformation; at the same time, the main tool head performs additive forming or equal-material forming on one side of the metal sheet, while the slave tool head performs subtractive forming or equal-material forming on the other side of the metal sheet.

[0015] Preferably, the additive material flows out from the channel inside the main tool head and is formed on one side surface of the metal sheet; during the forming process, the main tool head rotates synchronously as it moves, so that the channel outlet faces the center of the metal sheet.

[0016] Preferably, the additive layer formed on the surface of the metal sheet by the main tool head has a single layer thickness of no more than 0.5 mm.

[0017] Preferably, when the tool head rotates forward, the metal sheet is formed using an equal-material forming process; when the tool head rotates backward, the metal sheet is formed using a subtractive forming process.

[0018] The working principle of this invention is as follows: The metal sheet is placed and clamped onto the clamping device of the equipment. On one side of the metal sheet, an additive-equal-material forming process is performed using a main tool head (additive-incremental forming composite tool head). The main tool head moves along a set trajectory, applying a localized downward pressure load to the metal sheet, causing plastic deformation. Simultaneously, additive material flows out through the internal channels of the main tool head and spreads evenly on the surface of the metal sheet, solidifying to form an additive layer. On the other hand, on the other side of the metal sheet, a subtractive-equal-material forming process is performed using a follower tool head (subtractive-incremental forming composite tool head). The follower tool head moves in tandem with the main tool head along a set trajectory; forward rotation of the follower tool head performs incremental forming, while reverse rotation performs cutting.

[0019] Compared with the prior art, the present invention has the following beneficial effects: 1. Compared with traditional sheet metal forming processes, this invention can be used for integrated additive-equal-subtractive processing of high-performance thin-walled parts with characteristics such as heterogeneous materials, variable thickness and surface texture; specifically, progressive forming can be achieved by switching between additive, equal-material and subtractive forming as preset.

[0020] 2. Compared with traditional additive manufacturing methods, this invention can significantly improve the forming efficiency of heterogeneous thin-walled parts and reduce processing costs by combining additive manufacturing, equal material manufacturing, and subtractive manufacturing.

[0021] 3. The additive-incremental forming composite tool head can be used to prepare heterogeneous multi-metal composite thin-walled parts (the thickness, shape and even material type can be controlled and changed as needed). Combined with the subtractive-incremental forming composite tool head, the thickness of the thin-walled parts can be precisely controlled, which can be used for the application needs of high-performance heterogeneous thin-walled parts in aerospace and other fields.

[0022] 4. Compared with the traditional sequential manufacturing method of joining and forming, the present invention eliminates defects such as delamination and microcracks through a forming-joining composite processing method, improves the synergistic deformation capability of heterogeneous thin-walled parts, and enables the processed products to have sufficient connection strength and mechanical properties. Attached Figure Description

[0023] Figure 1 A schematic diagram of the flexible dual-point progressive forming equipment for simultaneous additive-equal-subtractive material composite processing in the processing preparation stage; Figure 2 A schematic diagram of the structure of a flexible dual-point progressive forming equipment for simultaneous additive-subtractive material composite processing during the manufacturing process; Figure 3 A schematic diagram of the structure of a heterogeneous variable thickness thin-walled part processed by a flexible dual-point progressive forming equipment for simultaneous additive-subtractive material composite processing; In the diagram: 1-Additive material; 2-Wire feeding device; 3-Heating device; 4-Main tool head; 5-Metal sheet; 6-Additive layer; 7-Clamping device; 8-Slave tool head. Detailed Implementation

[0024] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0025] A flexible two-point progressive forming device for simultaneous additive-subtractive material composite processing, such as... Figure 1 As shown, the device for progressive forming of sheet metal 5 includes a master tool head 4, a slave tool head 8, and a clamping device 7. The metal plate 5 is clamped on the clamping device 7, and the main tool head 4 and the slave tool head 8 are respectively disposed on both sides of the metal plate 5; The bottom surface of the main tool head 4 faces the metal sheet 5; the main tool head 4 has a flow channel for the additive material 1 inside, and the bottom of the side wall of the main tool head 4 has a flow channel outlet; the main tool head 4 performs additive-equivalent forming on one side surface of the metal sheet 5. The tool head 8 is positioned from the bottom surface toward the metal sheet 5; a cutting edge is provided circumferentially from the bottom of the tool head 8; and the tool head 8 performs subtractive-equal material forming on the other side surface of the metal sheet 5.

[0026] A flexible two-point incremental forming method for simultaneous additive-subtractive composite material processing, such as... Figure 1-3 As shown, the equipment described above is used; The method includes the following steps: S1: Clean and dry the metal sheet 5, and clamp and fix the metal sheet 5 onto the clamping device 7; S2: The main tool head 4 and the slave tool head 8 work together to apply a local downward pressure load to the metal sheet 5, causing the sheet to undergo plastic deformation; at the same time, the main tool head 4 performs additive forming or equal-material forming on one side of the metal sheet 5, and the slave tool head 8 performs subtractive forming or equal-material forming on the other side of the metal sheet 5.

[0027] Example 1 This embodiment provides an integrated additive-subtractive material progressive forming device.

[0028] The progressive forming equipment is mounted on a progressive forming fixture, specifically including a clamping device 7, a main tool head 4, and a slave tool head 8.

[0029] The clamping device 7 is fixedly installed on the progressive forming fixture and is used to securely clamp the metal sheet 5 for processing by the main tool head 4 and the slave tool head 8.

[0030] The main tool head 4 is located above the clamping device 7 (i.e., above the metal sheet 5) and is used for additive-equivalent forming of the metal sheet 5. Specifically, the main tool head 4 is as follows: Figure 1 The diagram shows a rigid flat-bottomed tool head with a bottom fillet radius of 1-5 mm. Inside the main tool head 4, a flow channel for the additive material 1 is provided. The end of the flow channel forms a flow channel outlet at the bottom of the side wall of the main tool head 4. Specifically, the height of the flow channel outlet can be 1-5 mm. A wire feeding device 2 and a heating device 3 are also provided upstream of the flow channel inside the main tool head 4. The wire feeding device 2 is located upstream of the heating device 3 (preferably at the entrance of the flow channel at the top of the main tool head 4) to feed the solid additive material 1 into the interior of the main tool head 4. The heating device 3 heats and melts the additive material 1 entering the main tool head 4 into a molten state, allowing it to flow through the flow channel and out through the flow channel outlet. The wire feeding device 2 can be a roller structure, and the heating device 3 can be an electric heating wire. The additive material 1 is a metal wire.

[0031] The main tool head 4 is mounted to the progressive forming fixture via an actuation device, which drives its lifting and rotation, thereby achieving: 1. The main tool head 4 travels along a predetermined trajectory; 2. The flow channel outlet is always oriented towards the center. This actuation device can be a robotic arm. By controlling the forming passes of the main tool head 4 and the flow channel width / additive material 1 flow rate, the thickness of the additive layer 6 formed in a single pass can be controlled to be 0.5 mm or less.

[0032] The tool head 8 is located below the clamping device 7 (i.e., below the metal sheet 5) and is used for subtractive-equivalent forming of the metal sheet 5. The tool head 8 is as follows... Figure 1 The image shows a rigid flat-bottomed tool head with a bottom fillet radius of 1-5 mm. Cutting edges are spaced circumferentially on its bottom surface, allowing for subtractive or equal-material forming of the lower surface of sheet metal 5. The helix angle of the cutting edges can be 30-60°, and the tool head 8 is configured to perform progressive forming when rotating clockwise and cutting when rotating counterclockwise (e.g., all cutting edges are sharpened only on the same side).

[0033] The tool head 8 is installed onto the progressive forming fixture via a motion device, which drives it to lift and rotate, thereby enabling: 1. The tool head 8 to travel along a predetermined trajectory; 2. The rotation direction of the tool head 8 to switch forming modes.

[0034] During operation, the main tool head 4 and the slave tool head 8 move in coordination relative to each other from the two sides of the metal sheet 5 to perform incremental forming of material according to a preset trajectory and action.

[0035] When using the equipment, the metal sheet 5 is placed and clamped on the clamping device 7. The designed additive-progressive forming composite tool head (main tool head 4) is used to perform additive-equal material forming on the upper surface of the metal sheet 5. The main tool head 4 moves along the set trajectory to apply a local downward pressure load to the metal sheet 5, causing the metal sheet 5 to undergo plastic deformation. Meanwhile, the additive material 1 is melted into a molten state by the wire feeding device 2 and the heating device 3, and then flows out through the internal channel of the main tool head 4. The main tool head 4 rotates synchronously during its movement to ensure that the channel opening is always inside the forming part. As the main tool head 4 moves, the additive material 1 is evenly spread and solidified on the upper surface of the metal sheet 5 to form the additive layer 6. On the other hand, a subtractive-progressive forming composite tool head (from tool head 8) is used to perform subtractive-equal material forming on the lower surface of the metal sheet 5. The from tool head 8 moves in coordination with the main tool head 4 according to the set trajectory. The forward rotation of the from tool head 8 is progressive forming, and the reverse rotation is cutting. When the tool head finishes processing, a progressively formed thin-walled part with a specified material and varying thickness can be obtained.

[0036] Example 2 This embodiment provides an integrated incremental forming method combining additive, equal-subtractive and additive materials.

[0037] Metal sheet 5 is placed on an incremental forming fixture and clamped and fixed by clamping device 7. Additive-incremental forming is performed on the upper surface of metal sheet 5 using an additive-incremental forming composite tool head (main tool head 4). The main tool head 4 moves along a set trajectory, causing the metal sheet 5 to undergo plastic deformation. At the same time, additive material 1 is melted into molten material through wire feeding device 2 and heating device 3. The main tool head 4 rotates synchronously during its movement to ensure that the flow channel is always inside the formed part. The molten material flows out through the internal flow channel of the main tool head 4 and spreads evenly on the upper surface of metal sheet 5 as the main tool head 4 moves, and then solidifies and compacts to form additive layer 6. On the other hand, subtractive-incremental forming is performed on the lower surface of metal sheet 5 using a subtractive-incremental forming composite tool head (secondary tool head 8). The secondary tool head 8 moves in coordination with the main tool head 4 along a specific trajectory. After processing, a progressively formed thin-walled part with customized material and thickness can be obtained.

[0038] like Figures 1-3 As shown, the heating device 3 and internal flow channel design of the main tool head 4 should ensure that the internal metal is always in a molten state; the thickness of the additive layer 6 can be controlled by the height between the main tool head 4 and the metal sheet 5 and the number of forming passes, and the height can be 1 mm or less; the tool head 8 rotates forward to perform progressive forming of equal material, and rotates backward to perform subtractive cutting; the additive material 1 should be a material with a low melting point.

[0039] The specific implementation process of this embodiment is as follows: S1. Clean and dry the surface of the metal sheet 5, then place it on the progressive forming fixture and clamp it in place by the clamping device 7. Use the main tool head 4 to perform additive-equal forming on the upper surface of the metal sheet 5. The main tool head 4 moves along the set contour trajectory to apply a local downward pressure load to the metal sheet 5, causing it to undergo plastic deformation.

[0040] S2. At the same time, the additive material 1 is melted into a molten material by the wire feeding device 2 and the heating device 3. The main tool head 4 rotates synchronously during the movement to ensure that the flow channel is always inside the forming part. The molten material flows out through the internal flow channel of the main tool head 4 and spreads evenly on the surface of the metal sheet 5 as the main tool head 4 moves, and then solidifies and compacts to form the additive layer 6.

[0041] S3. Subtractive-progressive forming composite tool head is used to perform subtractive-equal material forming on the lower surface of metal sheet 5. The tool head 8 moves in coordination with the main tool head 4 along a specific trajectory. When the tool head 8 rotates forward, equal material progressive forming is performed. When the tool head 8 rotates backward, subtractive cutting is performed.

[0042] S4. After processing is completed, a progressively formed thin-walled part of the specified material and thickness can be obtained.

[0043] This invention can be used for additive-progressive-subtractive integrated processing of high-performance thin-walled parts with heterogeneous materials, controllable thickness, and surface texture; the additive-progressive composite tool head can be used to prepare heterogeneous multi-metal composite structures to achieve better interface bonding effect; the subtractive-progressive composite tool head can be used to precisely control the thickness of thin-walled parts, which can be used for the customized needs of modern industry.

[0044] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A flexible dual-point progressive forming device for simultaneous additive-subtractive composite forming, used for progressive forming of metal sheets (5), characterized in that, The device includes a main tool head (4), a slave tool head (8), and a clamping device (7); The metal plate (5) is clamped on the clamping device (7), and the main tool head (4) and the secondary tool head (8) are respectively disposed on both sides of the metal plate (5); The bottom surface of the main tool head (4) is set facing the metal sheet (5); the main tool head (4) has a flow channel for the additive material (1) inside, and the bottom of the side wall of the main tool head (4) has a flow channel outlet; the main tool head (4) performs additive-equivalent forming on one side surface of the metal sheet (5); The tool head (8) is positioned from the bottom surface toward the metal sheet (5); a cutting edge is provided circumferentially from the bottom of the tool head (8); and the tool head (8) is used to perform subtractive-equal material forming on the other side surface of the metal sheet (5).

2. The flexible dual-point progressive forming equipment for simultaneous additive-subtractive material composite as described in claim 1, characterized in that, The top of the main tool head (4) is provided with a wire feeding device (2); The wire feeding device (2) is disposed on the flow channel and is used to input additive material (1) into the flow channel.

3. The flexible dual-point progressive forming equipment for simultaneous additive-subtractive material composite as described in claim 1, characterized in that, The top of the main tool head (4) is provided with a heating device (3); The heating device (3) is installed on the flow channel and is used to heat and melt the additive material (1) in the flow channel.

4. The flexible dual-point progressive forming equipment for simultaneous additive-subtractive material composite as described in claim 1, characterized in that, Both the main tool head (4) and the slave tool head (8) are flat-bottomed tool heads with a radius of 1~5mm for the bottom rounded corners.

5. The flexible dual-point progressive forming equipment for simultaneous additive-subtractive material composite as described in claim 1, characterized in that, The distance from the outlet of the flow channel to the bottom surface of the main tool head (4) is 1~5mm.

6. The flexible dual-point progressive forming equipment for simultaneous additive-subtractive material composite as described in claim 1, characterized in that, The helix angle of the cutting edge is 30~60°.

7. A flexible two-point progressive forming method for simultaneous additive-subtractive material composite processes, characterized in that, Performed using the equipment described in any one of claims 1 to 6; The method includes the following steps: S1: Clean and dry the metal sheet (5), and clamp and fix the metal sheet (5) on the clamping device (7); S2: The main tool head (4) and the slave tool head (8) work together to apply a local downward pressure load to the metal sheet (5) to cause plastic deformation of the sheet; at the same time, the main tool head (4) performs additive forming or equal material forming on one side of the metal sheet (5), and the slave tool head (8) performs subtractive forming or equal material forming on the other side of the metal sheet (5).

8. The flexible two-point progressive forming method for simultaneous additive-subtractive material composite as described in claim 7, characterized in that, The additive material (1) flows out from the channel inside the main tool head (4) and is formed on one side surface of the metal sheet (5); during the forming process, the main tool head (4) rotates synchronously as it moves, so that the channel outlet faces the middle of the metal sheet (5).

9. The flexible two-point progressive forming method for simultaneous additive-subtractive material composite as described in claim 7, characterized in that, The additive layer (6) formed on the surface of the metal sheet (5) by the main tool head (4) has a single layer thickness of no more than 0.5 mm.

10. A flexible two-point progressive forming method for simultaneous additive-subtractive composite material processing according to claim 7, characterized in that, When the tool head (8) rotates forward, the metal sheet (5) is formed by equal material forming; when the tool head (8) rotates backward, the metal sheet (5) is formed by subtractive material forming.

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