Split-flow combined die for producing aluminum profile with large extrusion ratio and ultra-thin wall structure

Abstract

The invention relates to a split-flow combined die for producing an aluminum profile with a large extrusion ratio and an ultra-thin wall structure, a material inlet of an upper die comprises a main split-flow bridge and an auxiliary split-flow bridge, the main split-flow bridge and the auxiliary split-flow bridge divide the material inlet to form split-flow holes, and the split-flow holes are uniformly distributed towards the outer side in the center of the die and are in central symmetry about the die; the discharging end of the main flow dividing bridge is connected with a mold core, and the lower mold is provided with a discharging port. The lower die is provided with a corresponding working tape corresponding to the die core according to the special structure of an extruded profile, and the length and shape of the working tape are accurately designed and processed to ensure that the working tape is as short as possible and is uniform, so that the local flow rate of metal is accurately controlled to enable the metal to uniformly flow in the extrusion process; the extrusion profile can break through the large extrusion ratio exceeding 120 and is precisely formed, the aluminum profile with the large extrusion ratio and the ultra-thin wall structure and meeting the requirement can be produced, the production efficiency is improved, the stress of a mold is reduced, and the service life of the mold is prolonged.

Description

Technical Field

[0001] The invention relates to a diversion combined die for producing aluminum profiles with a large extrusion ratio and ultra-thin wall structure, and belongs to the technical field of hot extrusion die manufacturing. Background Art

[0002] In 2022, CATL developed its third-generation power battery, the Kirin Battery. This battery pioneered large-surface cell cooling technology, with its core component being a large-area, ultra-thin-wall, precision water-cooled flat-tube aluminum extrusion. This ultra-thin, multi-cavity aluminum extrusion not only offers low density and high strength, but also excellent thermal conductivity, effectively ensuring the high power and safety of the power battery. Although the high-power Kirin Battery is currently only in the early stages of trial production, its application of large-surface cell cooling technology has already ignited the market for ultra-thin-wall, precision water-cooled flat-tube aluminum extrusions.

[0003] The forming of ultra-thin-walled multi-cavity aluminum alloy profiles undergoes complex hot and cold processing procedures such as melting, extrusion forming, and machining. First of all, the aluminum profile has thin walls, a large extrusion ratio, severe deformation, high extrusion force during production, and reduced stability of the mold core, all of which pose huge challenges to the extrusion method. Secondly, the flow pattern of metal in each cavity of the mold during the extrusion process determines the microstructure characteristics and service performance of the aluminum profile after extrusion. The metal flow behavior at each stage is complex and difficult to control. Mastering the metal flow pattern during the extrusion process and developing "shape" controlled integrated extrusion technology not only ensures the precise size of aluminum profile components, but also provides an ideal organizational structure to meet the service performance of aluminum profiles such as strength and airtightness, which has become a bottleneck in the manufacturing of such complex thin-walled aluminum alloy profiles.

[0004] In view of the above problems, it is very necessary to design and study a new type of diversion combination die for the production of large extrusion ratio ultra-thin-wall structural aluminum profiles to overcome the problems existing in the existing hot extrusion die. Summary of the Invention

[0005] In view of the deficiencies in the prior art, the technical problem to be solved by the present invention is to provide a splitter combined die for producing ultra-thin-walled aluminum profiles with a large extrusion ratio.

[0006] In order to solve the above technical problems, the technical solution of the present invention is: a diversion combination mold for producing ultra-thin-walled structural aluminum profiles with a large extrusion ratio, comprising an upper mold and a lower mold that cooperate with each other, and a feed port is provided on the feed end of the upper mold, and the feed port includes a main diversion bridge and an auxiliary diversion bridge, and the main diversion bridge and the auxiliary diversion bridge are in a cross shape on the upper mold, and the main diversion bridge and the auxiliary diversion bridge divide the feed port to form a diversion hole, and the diversion hole is evenly distributed outward from the center of the mold and is symmetrical about the center of the mold. The bridge positions of the main diversion bridge and the auxiliary diversion bridge are both lower than the discharge end face of the upper mold, and the discharge end of the main diversion bridge is connected to the mold core, the discharge end of the upper mold is provided with an upper weld, and the feed end of the lower mold is provided with a welding chamber corresponding to the upper weld, and the lower mold is provided with a discharge port, and the foreman on the mold core passes through the corresponding upper weld and welding chamber respectively and enters part of the depth of the discharge port.

[0007] Preferably, the height difference between the bridge positions of the main diverter bridge and the auxiliary diverter bridge and the discharge end face of the upper mold accounts for 10% of the total height of the upper mold. There are four diverter holes, and the cross-sectional shape of the diverter holes is a trapezoid, and there are arc-shaped transitions at the four corners of the trapezoid.

[0008] Preferably, the ratio between the width of the main diverter bridge and the width of the auxiliary diverter bridge is 1:0.8 to 1:0.9.

[0009] Preferably, adjacent side walls of two adjacent foremen on the mold core are both fixed with an arc-shaped structure with a notch facing downwards, the middle concave top of the arc-shaped structure is a flat structure, and the concave depth of the arc-shaped structure is 2 mm.

[0010] Preferably, the welding chamber of the lower die is butterfly-shaped, and the cross-sectional shape of the feed port corresponds to the cross-sectional shape of the welding chamber.

[0011] Preferably, the corners of the outer contour of the welding chamber are transitioned with a fillet of 1 mm to 5 mm.

[0012] Preferably, the lower die is provided with a corresponding working belt on the inner peripheral wall at the top of the discharge port according to the special structure of the extruded profile, and the working belt corresponds to the die core.

[0013] Preferably, the working belt has thin-walled platforms with arc-shaped bottom corners fixed on two opposite inner walls along the length direction according to the special structure of the extruded profile. The thin-walled platforms are used to correspond to each thin wall between the two holes of the extruded profile.

[0014] Preferably, end platforms are fixedly provided at both ends of the corresponding extruded profile in the width direction according to the shapes of the profiles, and the bottoms of both ends of the end platforms transitionally connect with the length direction of the working belt through arc-shaped corners.

[0015] Preferably, the arc radius of the bottom corner of the thin-walled platform is 1 mm, and the height of the thin-walled platform is 1.6 mm; the height of the end platform is 1.6 mm, and the radius of the arc corner is 2 mm.

[0016] Compared with the prior art, the present invention has the following beneficial effects: the diversion combination die for producing ultra-thin-walled aluminum profiles with a large extrusion ratio can achieve precise forming of ultra-thin-walled aluminum profiles with a large extrusion ratio, break through the limitation of the large extrusion ratio, and meet the dimensional tolerances required for ultra-thin-walled aluminum profiles, thereby improving production efficiency, reducing mold stress and extending mold service life.

[0017] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A perspective view of an embodiment of the present invention; Figure 2 is a three-dimensional diagram of the upper mold; Figure 3 for Figure 2 A partial enlarged view; Figure 4 is a three-dimensional diagram of the lower mold; Figure 5 for Figure 4 B is a partial enlarged view; Figure 6 It is a partial enlarged view of the thin-wall platform and the end platform; Figure 7 A front view of an embodiment of the present invention; Figure 8 for Figure 7 CC cross-sectional view; Figure 9 A top view of an embodiment of the present invention; Figure 10 for Figure 9 DD cross-sectional view; Figure 11 This is a schematic diagram of the profile structure extruded according to an embodiment of the present invention; Figure 12 This is the finite element simulation extrusion velocity result 1 of an embodiment of the present invention; Figure 13 This is the second finite element simulation extrusion velocity result of an embodiment of the present invention; Figure 14 This is a diagram of a trial sample of an embodiment of the present invention.

[0019] In the figure: 1. Upper die, 1-1. Main diverter bridge, 1-2. Auxiliary diverter bridge, 1-3. Diverter hole, 1-4. Arc structure, 1-5. Mold core, 1-51. Foreman, 1-6. Upper weld, 1-7. Arc structure, 2. Lower die, 2-1. Welding chamber, 2-2. Discharge port, 2-3. Working belt, 2-4. Thin-wall platform, 2-5. End platform, 2-6. Arc corner. DETAILED DESCRIPTION

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0022] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0023] like Figures 1 to 14 As shown, this embodiment provides a diversion combination die for producing ultra-thin-walled aluminum profiles with a large extrusion ratio, which belongs to the field of hot extrusion die manufacturing technology. The wall thickness of the profile formed by extrusion is required to be ±0.05mm, wherein the extrusion ratio is greater than 120, and the die includes an upper die 1 and a lower die 2 that cooperate with each other. A feed port is provided on the feed end of the upper die 1, and the feed port includes a main diversion bridge 1-1 and an auxiliary diversion bridge 1-2. The main diversion bridge 1-1 and the auxiliary diversion bridge 1-2 are in a cross shape on the upper die 1. The main diversion bridge 1-1 and the auxiliary diversion bridge 1-2 divide the feed port to form a diversion hole 1-3. The diversion holes 1-3 are evenly distributed outward from the center of the mold and are symmetrical about the center of the mold. The bridge positions of the main diversion bridge 1-1 and the auxiliary diversion bridge 1-2 are both lower than the discharge end face of the upper mold 1. The discharge end of the main diversion bridge 1-1 is connected to the mold core 1-5. The discharge end of the upper mold 1 is provided with an upper weld 1-6, and the feed end of the lower mold 2 is provided with a welding chamber 2-1 corresponding to the upper weld 1-6. The lower mold 2 is provided with a discharge port 2-2, and the foreman 1-51 of the mold core 1-5 passes through the corresponding upper weld 1-6 and the welding chamber 2-1 and enters part of the depth of the discharge port 2-2.

[0024] In an embodiment of the present invention, the height difference between the bridge positions of the main diverter bridge 1-1 and the auxiliary diverter bridge 1-2 and the discharge end face of the upper mold 1 accounts for 10% of the total height of the upper mold 1. There are four diverter holes 1-3, and the cross-sectional shape of the diverter holes 1-3 is a trapezoid, and there are arc-shaped transitions at the four corners of the trapezoid.

[0025] In an embodiment of the present invention, the main diverter bridge 1-1 and the auxiliary diverter bridge 1-2 have an arc-shaped structure 1-4 with outwardly convex middle portions on both sides at the feed end, while the middle portion remains flat. This effectively increases the amount of molten aluminum and the guiding type, while ensuring the main body width of the main diverter bridge 1-1 and the auxiliary diverter bridge 1-2, making them less susceptible to breakage. In addition, this structure can pre-cut the aluminum rod, causing it to be pre-deformed into multiple streams that enter the corresponding diverter holes 1-3. Compared to conventional flat combination dies, this design can effectively reduce the pressure area of ​​the diverter bridge, disperse stress, improve the bearing capacity of the diverter bridge, and reduce the pressure on the entire mold, thereby reducing the extrusion force and the breakthrough pressure of the extruded product.

[0026] In an embodiment of the present invention, four trapezoidal diverter holes 1-3 are provided in a centrally symmetrical manner. Each trapezoidal diverter hole 1-3 has a lower base length of 50 mm, an upper base length of 40 mm, and a height of 25 mm. A rounded arc transition with a radius of 2 mm is provided at the four corners. By increasing the area of ​​the diverter holes, the resistance to the flow to the welding chamber is reduced, thereby promoting uniform metal flow. The main diverter bridge 1-1 and the auxiliary diverter bridge 1-2 are in a cross shape, dividing the aluminum rod into four equal streams, ensuring a balanced metal flow and ensuring higher quality of the extruded product. The ratio of the width of the main diverter bridge 1-1 to the width of the auxiliary diverter bridge 1-2 is 1:0.8 to 1:0.9, which optimizes the ratio of the widths of the two diverter bridges and improves the metal flow efficiency and the mold's ability to resist deformation.

[0027] In an embodiment of the present invention, the cooperation between the mold core 1-5 and the working belt 2-3 ensures that the shape and size of the extruded profile meet production requirements. The adjacent side walls of the two adjacent foremen 1-51 on the mold core 1-5 are fixed with an arc-shaped structure with a notch facing downward. The middle concave top of the arc structure is a flat structure, and the depth of the concave of the arc structure is 2mm. This structure can reduce the force on the edge of the mold core 1-5, improve the stability of the mold core 1-5, extend the service life of the mold, and prevent the edge of the mold core from breaking and falling off, and increase the flow rate at the thin wall of the metal, so that the flow of the entire metal cross-section during the extrusion process is more uniform. According to the special structure of the extruded profile, the working belt 2-3 is fixed with thin-walled platforms with arc-shaped bottom corners on the two opposite inner walls in the length direction. The thin-walled platforms are used to correspond to each thin wall between the two holes of the extruded profile. The width direction of the working band 2-3 is fixed with end platforms at both ends of the corresponding extruded profile, based on the shape of the profile. The bottom of each end platform transitions to the length direction of the working band 2-3 through curved corners. The arc radius of the bottom corner of the thin-walled platform is 1mm, and the height of the thin-walled platform is 1.6mm; the height of the end platform is 1.6mm, and the radius of the curved corner is 2mm. Through precise design and processing of the working band length, the precise forming of the extruded profile is guaranteed, keeping the working band as short and uniform as possible, and ensuring uniform metal flow, reducing frictional resistance, allowing the extruded profile to break through the high extrusion ratio of 120 and accurately form, meeting the requirement of ±0.05mm wall thickness of the extruded profile.

[0028] In an embodiment of the present invention, the welding chamber 2-1 is a butterfly-shaped welding chamber with a horizontal length of 140 mm, a vertical length of 67 mm, and a depth of 10 mm. By increasing the volume and depth of the welding chamber, sufficient space is provided for the metal to be fully welded. While reducing the welding pressure, it also helps to dissipate heat, improve the service life of the mold, and help the metal flow more evenly during extrusion. The outer contour of the welding chamber 2-1 is transitioned with a radius of 1 mm to 5 mm, which can reduce the flow dead zone and turbulence of the metal during flow, and avoid the increase of the flow dead zone causing the welding chamber 2-1 to become clogged. In the present invention, the radial length of the upper weld 1-6 is the same as that of the welding chamber 2-1, which significantly improves the weld quality of the extruded product, improves the overall performance and surface finish of the profile, simplifies mold manufacturing, and helps to extend the life of the mold.

[0029] In the embodiment of the present invention, the present invention also performs finite element simulation analysis on the whole, specifically, Figure 12 and Figure 13As shown in the figure, according to the set extrusion process, the simulation results of the extruded profiles show that the wall thickness of the profiles meets the requirement of ±0.05mm, the pressure fluctuation range in the diversion hole is as low as 18.7MPa (386.2MPa - 404.9MPa) and as high as 20.2MPa (385.9MPa- 406.1MPa), and the pressure distribution between different diversion channels is relatively uniform; the temperature fluctuation range in the diversion hole is as low as 2°C (443.8°C - 445.8°C) and as high as 2.2°C (443.7°C - 445.9°C), and the temperature distribution between different diversion channels is uniform; the deviation of the flow velocity field in the profile section is 0.2mm·s -1 , the temperature difference of the profile surface did not exceed 5%, which shows that the outlet of the extruded profile was very uniform, and the outlet profile did not have quality problems such as deformation, inconsistent flow rate, dimensional deviation and wavy surface.

[0030] In the embodiment of the present invention, Figure 14 As shown, samples were obtained through trial production. Through testing and analysis of the samples, it was found that the ultra-thin wall thickness of the samples was uniform and met the standards, the multi-cavity structure was complete and without distortion, and the dimensional accuracy requirements could be met. In addition, the profile surface had no cracks, no serious scratches, excellent welding lines, and no obvious surface defects, which could meet the production requirements.

[0031] The present invention proposes a diversion combination die for producing ultra-thin-walled aluminum profiles with a large extrusion ratio. The die core and the lower die working band are precisely shaped to ensure that the metal outflow rate is uniform during the extrusion process, so that the extruded profile will not deflect at a large angle. Four large diversion holes similar to trapezoids are set symmetrically at the center and arc-shaped at the four corners to reduce the resistance to the welding chamber and promote uniform metal flow. The butterfly-shaped welding chamber is then designed and the volume and depth of the welding chamber are appropriately increased to provide sufficient space for the metal to be fully welded, reducing the welding pressure. The outer contour of the welding chamber is transitioned with rounded corners to make the metal flow more uniform. A corner design is added inside the extrusion die, and the radius of the arc fillet is increased to promote smoother metal flow, reduce the accumulation and retention of metal inside the die, greatly reduce the occurrence of accidents such as die blocking, and improve the surface quality and dimensional accuracy of the profile. The above design makes the metal flow more uniform during the extrusion process, breaks through the limitation of large extrusion ratio, and can accurately form profiles with an extrusion ratio of 120.

[0032] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other manner. Any person skilled in the art may utilize the above-disclosed technical content to modify or modify the present invention into equivalent embodiments. However, any simple modifications, equivalent variations, and modifications to the above embodiments that do not depart from the technical content of the present invention and are based on the technical essence of the present invention remain within the scope of protection of the present invention.

Claims

1. A splitter assembly die for producing ultra-thin-walled aluminum profiles with a large extrusion ratio, characterized by: The invention comprises an upper die (1) and a lower die (2) that cooperate with each other, wherein a feed port is provided on the feed end of the upper die (1), wherein the feed port comprises a main diverter bridge (1-1) and an auxiliary diverter bridge (1-2), wherein the main diverter bridge (1-1) and the auxiliary diverter bridge (1-2) are in a cross shape on the upper die (1), wherein the main diverter bridge (1-1) and the auxiliary diverter bridge (1-2) divide the feed port to form diverter holes (1-3), wherein the diverter holes (1-3) are evenly distributed from the center of the die to the outside and are symmetrical about the center of the die, wherein the main diverter bridge (1-1) and the auxiliary diverter bridge The bridge positions of (1-2) are all lower than the discharge end face of the upper mold (1), the discharge end of the main diversion bridge (1-1) is connected to the mold core (1-5), the discharge end of the upper mold (1) is provided with an upper weld (1-6), the feed end of the lower mold (2) is provided with a welding chamber (2-1) corresponding to the upper weld (1-6), the lower mold (2) is provided with a discharge port (2-2), and the foreman (1-51) on the mold core (1-5) passes through the corresponding upper weld (1-6) and the welding chamber (2-1) and enters a partial depth of the discharge port (2-2).

2. The splitter assembly die for producing ultra-thin-walled aluminum profiles with a large extrusion ratio according to claim 1, characterized in that: The height difference between the bridge positions of the main diverter bridge (1-1) and the auxiliary diverter bridge (1-2) and the discharge end surface of the upper mold (1) accounts for 10% of the total height of the upper mold (1). There are four diverter holes (1-3), and the cross-sectional shape of the diverter holes (1-3) is a trapezoid, and the four corners of the trapezoid are all arc-shaped transitions.

3. The splitter assembly die for producing ultra-thin-walled aluminum profiles with a large extrusion ratio according to claim 1, characterized in that: The ratio between the width of the main shunt bridge (1-1) and the width of the auxiliary shunt bridge (1-2) is 1:0.8 to 1:0.

9.

4. The splitter assembly die for producing ultra-thin-walled aluminum profiles with a large extrusion ratio according to claim 1, characterized in that: Adjacent side walls of two adjacent foremen (1-51) on the mold core (1-5) are both fixedly provided with an arc-shaped structure (1-7) with a notch facing downwards, the middle concave top of the arc-shaped structure being a flat structure, and the concave depth of the arc-shaped structure being 2 mm.

5. The splitter assembly die for producing ultra-thin-walled aluminum profiles with a large extrusion ratio according to claim 1, characterized in that: The welding chamber (2-1) of the lower die (2) is butterfly-shaped, and the cross-sectional shape of the feed port corresponds to the cross-sectional shape of the welding chamber (2-1).

6. The splitter assembly die for producing ultra-thin-walled aluminum profiles with a large extrusion ratio according to claim 1, characterized in that: The corners of the outer contour of the welding chamber (2-1) are transitioned with a fillet of 1mm to 5mm.

7. The splitter assembly die for producing ultra-thin-walled aluminum profiles with a large extrusion ratio according to claim 1, characterized in that: The lower die (2) is provided with a corresponding working belt (2-3) on the inner peripheral wall at the top of the discharge port (2-2) according to the special structure of the extruded profile, and the working belt (2-3) corresponds to the die core (1-5).

8. The splitter assembly die for producing ultra-thin-walled aluminum profiles with a large extrusion ratio according to claim 7, characterized in that: According to the special structure of the extruded profile, the working belt (2-3) has thin-walled platforms (2-4) with arc-shaped bottom corners fixedly provided on two opposite inner walls in the longitudinal direction thereof at intervals along the longitudinal direction. The thin-walled platforms are used to correspond to each thin wall between two holes in the extruded profile.

9. The splitter assembly die for producing ultra-thin-walled aluminum profiles with a large extrusion ratio according to claim 8, characterized in that: The working belt (2-3) is provided with end platforms (2-5) at both ends of the corresponding extruded profile in the width direction according to the shapes of the profile at both ends, and the bottoms of both ends of the end platforms transitionally connect with the working belt (2-3) in the length direction via arc-shaped corners (2-6).

10. The splitter assembly die for producing ultra-thin-walled aluminum profiles with a large extrusion ratio according to claim 9, characterized in that: The arc radius of the bottom corner of the thin-walled platform is 1 mm, and the height of the thin-walled platform is 1.6 mm; the height of the end platform is 1.6 mm, and the radius of the arc corner is 2 mm.

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