An aluminum alloy battery pack bracket and a manufacturing process thereof

Abstract

This invention relates to the field of aluminum alloy battery pack bracket processing technology, and in particular to an aluminum alloy battery pack bracket and its manufacturing process. The manufacturing process includes: blanking to obtain a bar stock; mold heating to heat the forging mold; forging to place the bar stock into the heated forging mold and forge it into shape, obtaining a preliminary aluminum alloy battery pack bracket; trimming to remove waste edges, obtaining an intermediate aluminum alloy battery pack bracket; solution treatment and aging to sequentially perform solution treatment and aging treatment on the intermediate aluminum alloy battery pack bracket, obtaining a heat-treated aluminum alloy battery pack bracket; inspection and packaging. This invention optimizes solution treatment and aging, reducing forming stress to reduce the size of the stress-induced damage and stress residue area in the workpiece, ultimately reducing the growth degree of coarse grains in the stress area; simultaneously, the forging mold solves the problems of difficult placement and positioning of the raw material bar during forging, preventing folding caused by the deflection of the raw material bar, and solving the problem of low utilization rate caused by uneven material flow in various directions.

Description

Technical Field

[0001] This invention relates to the field of aluminum alloy battery pack bracket processing technology, and in particular to an aluminum alloy battery pack bracket and its manufacturing process. Background Technology

[0002] An aluminum alloy battery pack bracket is a mounting bracket used to secure battery packs in electric or hybrid vehicles. With the increasing prevalence of electric vehicles, the safe and stable securing of battery packs has become paramount. The aluminum alloy battery pack bracket provides robust support and fixation, ensuring the stability and safety of the battery pack during vehicle operation.

[0003] The existing aluminum alloy battery pack bracket is made of 6-series aluminum alloy material. The composition of 6-series aluminum alloy material is (by mass percentage): 0.7-1.3% Si, 0.5% Fe, 0.1% Cu, 0.4-1.0% Mn, 0.6-1.2% Mg, 0.25% Cr, 0.2% Zn, 0.1% Ti and the balance Al.

[0004] Due to space constraints and weight reduction requirements in the battery assembly, the aluminum alloy battery pack bracket must be a thin-walled component, with a thickness of less than 6mm. In existing technologies, the common coarse-grained standard for similar small-sized forgings is a surface thickness ≤3mm (source: GB / T34359-2017, 5.4.4.3), meaning the sum of the upper and lower surfaces is 6mm. For thin-walled components, the coarse-grained layer obtained by the above process would result in a very thin working thickness, significantly affecting the mechanical properties of the workpiece.

[0005] For forging thin-walled aluminum alloy parts, a single-stage forming process is generally adopted. However, for some complex workpieces, single-stage forging can easily cause folding defects, leading to a high scrap rate and unstable workpiece quality. Summary of the Invention

[0006] The technical problem to be solved by this invention is to overcome the shortcomings of the prior art and provide an aluminum alloy battery pack bracket and its manufacturing process. This invention optimizes solution treatment and aging, reduces forming stress to minimize stress damage and the size of the stress residue area in the workpiece, controls the growth degree of coarse grains within the stress area, and improves the mechanical properties of the workpiece. Simultaneously, the forging die solves the problems of difficult placement and positioning of raw material bars during forging, prevents folding caused by deflection of the raw material bars, and addresses the problem of low utilization rate caused by uneven material flow in various directions.

[0007] The technical solution adopted by this invention to solve its technical problem is:

[0008] An aluminum alloy battery pack bracket includes a long plate portion and a short plate portion connected to each other, wherein the long plate portion and the short plate portion are arranged in a V-shape.

[0009] The upper and lower surfaces of the long plate are provided with several small protrusions, and the connection between the long plate and the short plate is set with rounded corners, with a large protrusion in the middle of the connection.

[0010] Furthermore, the thickness of the thinnest part A of the aluminum alloy battery pack bracket is 5-7 mm.

[0011] A manufacturing process for an aluminum alloy battery pack bracket as described above specifically includes the following steps:

[0012] Step S1: Feeding the material to obtain bar stock;

[0013] Step S2: Heating the mold; the forging mold is heated.

[0014] Step S3: Pre-forging. The bar obtained in step S1 is placed into a heated pre-forging mold and pre-forged to form an aluminum alloy battery pack bracket pre-forged part. Before pre-forging, the temperature of the bar is 520-560℃.

[0015] Step S4: Final forging. The aluminum alloy battery pack bracket pre-forging obtained in step S3 is placed into a heated final forging mold and forged to obtain the final forging of the aluminum alloy battery pack bracket.

[0016] Step S5: Trim the edges. Place the final forging of the aluminum alloy battery pack bracket obtained in step S4 into the trimming device to remove the waste edges and obtain the intermediate product of the aluminum alloy battery pack bracket.

[0017] Step S6: Water cooling. The intermediate aluminum alloy battery pack bracket obtained in step S5 is cooled in water. The temperature of the intermediate aluminum alloy battery pack bracket before water immersion is ≥400℃.

[0018] Step S7, solution treatment and aging: The intermediate aluminum alloy battery pack bracket after step S6 is subjected to solution treatment and aging treatment in sequence to obtain the heat-treated aluminum alloy battery pack bracket; wherein, the solution treatment process is: solution temperature of 515~535℃, solution time of 80~120min, and the aging treatment process is: aging temperature of 165~185℃, aging time of 6~10h;

[0019] Step S8: Inspect the packaging;

[0020] In step S3, the deformation of the aluminum alloy battery pack bracket pre-forging part from the bar stock to the aluminum alloy battery pack bracket pre-forging part is 86%; in step S4, the deformation of the aluminum alloy battery pack bracket pre-forging part to the aluminum alloy battery pack bracket final forging part is 15%.

[0021] The formation of coarse-grained regions in aluminum alloy products is due to stress damaging the aluminum alloy's crystalline structure and the residual stress within the crystalline structure. The size of this stress-affected region within the product determines the size of the area where coarse grains can grow. Then, under heat treatment within normal parameter ranges, the crystalline structure undergoes transformation and recrystallization, allowing coarse grains to grow within this stress-affected region. This invention optimizes solution treatment and aging, reducing forming stress to minimize the size of the stress-damaged and residual stress areas within the workpiece, ultimately reducing the degree of coarse grain growth within the stress region.

[0022] Furthermore, the pre-forging in step S3 and the final forging in step S4 are operated on the same forging die. The forging die includes an upper forging die and a lower forging die located directly below the upper forging die. The upper forging die and the lower forging die are provided with a pre-forging die cavity and a final forging die cavity for forging the blank. The pre-forging die cavity includes an upper die pre-forging cavity located on the upper forging die and a lower die pre-forging cavity located on the lower forging die.

[0023] The upper die pre-forging cavity includes two pre-forging upper die cavities of the same shape. The two pre-forging upper die cavities are symmetrically arranged about the center of the upper die pre-forging cavity. The centers of the two pre-forging upper die cavities are respectively located on both sides of the center of the upper die pre-forging cavity. Each pre-forging upper die cavity has a long side portion. A first upper material blocking groove is opened on the outer side of the long side portion. A second upper material blocking groove is opened on the outer side of the two pre-forging upper die cavities at the ends that are far apart from each other. A first upper positioning groove is opened on the ends that are far apart from each other. A second upper positioning groove is opened on the ends that are close to each other.

[0024] The lower die pre-forging cavity includes two pre-forging lower die cavities of the same shape. The two pre-forging lower die cavities correspond one-to-one with the two pre-forging upper die cavities. Each pre-forging lower die cavity has a large plane for forming the long side of the blank and a small plane for forming the short side of the blank. The large plane and the small plane are arranged in a V-shape. A first lower positioning groove is formed on the large plane, and a second lower positioning groove is formed on the small plane. A first lower blocking groove corresponding to the first upper blocking groove is formed on the outer side of the large plane. A second lower blocking groove corresponding to the second upper blocking groove is formed on the outer side of the two pre-forging lower die cavities at the ends that are far apart from each other.

[0025] The specific technical effects are as follows: The pre-forging die cavity adopts a two-cavity design, which can meet the requirement of producing two parts in one forging, thus improving production efficiency; due to the special shape of the aluminum alloy battery pack bracket pre-forging part, the material flow resistance to the short side is large during the pre-forging process. By setting the first upper and lower material blocking grooves, the metal flow direction can be changed, which is conducive to the material flowing from the long side to the short side; by setting the second upper and lower material blocking grooves, the metal flow direction can be further changed, preventing the material from flowing to both ends instead of the short side during the pre-forging process, thus further improving material utilization. The design incorporates a offset in both the left and right directions between the center of the two pre-forging upper cavities and the center of the upper pre-forging cavity. This ensures that the raw material bar will not deflect during the pre-forging process, preventing the two ends of the raw material bar from deflecting into the cavity and causing folding defects. It also saves the step of chamfering the raw material bar. The second upper positioning groove and the lower positioning groove ensure accurate positioning of the raw material bar. The first upper positioning groove is set at both ends. During the pressing process of the forging upper die, the two ends of the raw material bar are pressed and can still be stuck in the first upper positioning groove, which plays a role in assisting the positioning of the raw material bar.

[0026] Furthermore, the final forging die cavity includes an upper die final forging cavity located in the upper forging die and a lower die final forging cavity located in the lower forging die.

[0027] Furthermore, the upper forging die cavity includes two upper forging die cavities of the same shape, and the two upper forging die cavities are symmetrically arranged about the center of the upper forging die cavity; each upper forging die cavity has a stepped hole.

[0028] The specific technical effect is that by adopting a stepped hole design, a clamping column is placed on the workpiece blank. The stepped hole design can squeeze the excess material on the clamping column during the final forging pressing process, preventing folding defects caused by the excess material from occurring on the working surface of the workpiece blank.

[0029] Furthermore, the lower die final forging cavity includes two lower die cavities of the same shape, which are symmetrically arranged about the center of the lower die final forging cavity and correspond one-to-one with the two upper die cavities of the final forging.

[0030] The specific technical benefits are: the final forging die cavity adopts a two-cavity design, which can meet the requirement of producing two pieces in one forging, thus improving production efficiency.

[0031] Furthermore, each of the pre-forging upper die cavities has a short side portion, which is arranged in a V-shape with the long side portion, and the connection between the short side portion and the long side portion is rounded; a plane is also formed at the connection between the short side portion and the long side portion.

[0032] The specific technical effects are as follows: A larger radius fillet is used at the junction of the short and long sides to facilitate smoother material flow and prevent forging defects such as large folds and material shortages. A flat surface is also provided at the junction of the short and long sides due to the special shape of the aluminum alloy battery pack bracket pre-forging. This design further facilitates material flow and improves the coarse grain structure on the working plane.

[0033] Furthermore, the forging die also includes: a lower spring, a lower inner top plate, a lower ejector rod, a lower outer top plate, and a lower ejector pad. The lower ejector pad, the lower outer top plate, and the lower inner top plate are sequentially arranged at the lower end of the forging lower die along the direction close to the upper forging die. One end of the lower spring extends into the lower forging die, and the other end of the lower spring passes through the lower inner top plate and is connected to the lower outer top plate. One end of the lower ejector rod abuts against the lower outer top plate, and the other end of the lower ejector rod passes through the lower inner top plate and extends into the lower forging die.

[0034] Furthermore, the forging die also includes: an upper spring, an upper inner top plate, an upper ejector rod, an upper outer top plate, and an upper ejector pad. The upper ejector pad, the upper outer top plate, and the upper inner top plate are sequentially arranged at the upper end of the forging upper die along the direction close to the lower forging die. One end of the upper spring extends into the upper forging die, and the other end of the upper spring passes through the upper inner top plate and is connected to the upper outer top plate. One end of the upper ejector rod abuts against the upper outer top plate, and the other end of the upper ejector rod passes through the upper inner top plate and extends into the upper forging die.

[0035] Furthermore, the forging die also includes a pressure block and a date stamp, both of which are disposed within the upper forging die, with the pressure block abutting against the date stamp.

[0036] Furthermore, a release agent is required in both step S3 (pre-forging) and step S4 (final forging), and the release agent is a water-based graphite release agent.

[0037] The beneficial effects of this invention are as follows: This invention is rationally designed and has the following advantages:

[0038] (1) The present invention optimizes the forging process and solution aging, reduces forming stress to reduce the size of the stress damage and stress residue area in the workpiece, and ultimately reduces the growth degree of coarse grains in the stress area, thereby improving the mechanical properties of the workpiece.

[0039] (2) In the forging die, by setting the first upper material blocking groove and the first lower material blocking groove, the metal flow direction can be changed, which is conducive to the material flowing from the long side to the short side; by setting the second upper material blocking groove and the second lower material blocking groove, the metal flow direction can be changed, which can prevent the material from flowing to both ends instead of flowing to the short side during the pre-forging process, and further improve the material utilization rate.

[0040] (3) In the forging die, by adopting the design that the center of the two pre-forging upper die cavities and the center of the upper die pre-forging cavity are offset in the left and right directions, it can be ensured that the raw material bar will not deflect during the pre-forging process, and the process of chamfering the raw material bar is also saved. By setting the second upper positioning groove, the first lower positioning groove and the second lower positioning groove, the raw material bar can be accurately positioned. The first upper positioning groove is set at both ends of the pre-forging die cavity. During the pressing of the forging upper die, the two ends of the raw material bar are pressed and can still be stuck in the first upper positioning groove, which plays a role in assisting the positioning of the raw material bar. Attached Figure Description

[0041] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0042] Figure 1 This is a perspective view of the aluminum alloy battery pack bracket in this invention;

[0043] Figure 2 This is a perspective view of the aluminum alloy battery pack bracket in this invention from another angle;

[0044] Figure 3 This is a schematic diagram of the aluminum alloy battery pack bracket placed in the forging mold in this invention;

[0045] Figure 4 This is a schematic diagram of the forging die in this invention;

[0046] Figure 5 This is an exploded view of the forging die in this invention;

[0047] Figure 6 This is a schematic diagram of the forging upper die of the forging mold in this invention;

[0048] Figure 7 This is a front view of the forging upper die of the forging mold in this invention;

[0049] Figure 8 This is a schematic diagram of the structure of the lower forging die of the forging mold in this invention;

[0050] Figure 9 This is a front view of the lower forging die of the forging mold in this invention;

[0051] Figure 10 This is a front view of the forging die in this invention;

[0052] Figure 11 yes Figure 10 Sectional view at point AA;

[0053] Figure 12 yes Figure 9 Sectional view at point BB;

[0054] Figure 13 yes Figure 7 Sectional view at point CC.

[0055] In the picture:

[0056] 1-1. Long board section; 1-2. Short board section; 1-3. Small protrusion; 1-4. Large protrusion;

[0057] 1. Forging upper die; 2. Forging lower die; 3. Pre-forging upper die cavity; 4. First upper blocking groove; 5. Second upper blocking groove; 6. First upper positioning groove; 7. Second upper positioning groove; 8. Pre-forging lower die cavity; 9. First lower blocking groove; 10. Second lower blocking groove; 11. First lower positioning groove; 12. Final forging upper die cavity; 13. Stepped hole; 14. Final forging lower die cavity; 15. Rounded corner; 16. Flat surface; 17. Lower spring; 18. Lower inner top plate; 9. Lower push rod; 20. Lower outer top plate; 21. Lower push-out pad; 22. Upper spring; 23. Upper inner top plate; 24. Upper push rod; 25. Upper outer top plate; 26. Upper push-out pad; 27. Pressure block; 28. Date stamp; 29. ​​First screw group; 30. Second screw group; 31. Third screw group; 32. Lower circular pressure plate; 33. Large plane; 34. Small plane; 35. Second lower positioning groove; 36. Long side; 37. Short side. Detailed Implementation

[0058] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0059] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application. As used herein, the singular form includes the plural form unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this description, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0060] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0061] Example 1

[0062] like Figures 1-3 An aluminum alloy battery pack bracket shown includes a long plate portion 1-1 and a short plate portion 1-2 connected to each other, with the long plate portion 1-1 and the short plate portion 1-2 arranged in a V-shape.

[0063] The upper and lower surfaces of the long plate 1-1 are provided with several small protrusions 1-3. The connection between the long plate 1-1 and the short plate 1-2 is set as a rounded corner connection, and a large protrusion 1-4 is provided in the middle of the connection.

[0064] The thickness of the thinnest part A of the aluminum alloy battery pack bracket is 5.6mm.

[0065] A manufacturing process for an aluminum alloy battery pack bracket specifically includes the following steps:

[0066] Step S1: Feeding the material to obtain a bar stock with a diameter of 45mm. Heat the bar stock to 520℃.

[0067] Step S2: Heating the mold. The forging mold is heated to a temperature of 280°C.

[0068] Step S3: Pre-forging. The bar obtained in step S1 is placed into a heated pre-forging mold and pre-forged to form an aluminum alloy battery pack bracket pre-forged part. Before pre-forging, the temperature of the bar is 520-560℃.

[0069] Step S4: Final forging. The aluminum alloy battery pack bracket pre-forging obtained in step S3 is placed into a heated final forging mold and forged to obtain the final forging of the aluminum alloy battery pack bracket.

[0070] Step S5: Trim the edges. Place the final forging of the aluminum alloy battery pack bracket obtained in step S4 into the trimming device to remove the waste edges and obtain the intermediate product of the aluminum alloy battery pack bracket.

[0071] Step S6: Water cooling. The intermediate aluminum alloy battery pack bracket obtained in step S5 is cooled in water. The temperature of the intermediate aluminum alloy battery pack bracket before water immersion is ≥400℃.

[0072] Step S7, solution treatment and aging: The intermediate aluminum alloy battery pack bracket after step S6 is subjected to solution treatment and aging treatment in sequence to obtain the heat-treated aluminum alloy battery pack bracket; wherein, the solution treatment process is: solution temperature is 515℃, solution time is 80min, and the aging treatment process is: aging temperature is 165℃, aging time is 6h.

[0073] Step S8: Inspect the packaging;

[0074] In step S3, the deformation of the aluminum alloy battery pack bracket pre-forging part from the bar stock to the aluminum alloy battery pack bracket pre-forging part is 86%; in step S4, the deformation of the aluminum alloy battery pack bracket pre-forging part to the aluminum alloy battery pack bracket final forging part is 15%.

[0075] like Figures 4-13 As shown, the forging die includes: an upper forging die 1 and a lower forging die 2 located directly below the upper forging die 1. The upper forging die 1 and the lower forging die 2 are provided with a pre-forging die cavity and a final forging die cavity for forging blanks. The pre-forging die cavity includes an upper die pre-forging cavity located in the upper forging die 1 and a lower die pre-forging cavity located in the lower forging die 2.

[0076] The upper die pre-forging cavity includes two pre-forging upper die cavities 3 of the same shape. The two pre-forging upper die cavities 3 are symmetrically arranged about the center of the upper die pre-forging cavity. The centers of the two pre-forging upper die cavities 3 are located on both sides of the center of the upper die pre-forging cavity. Each pre-forging upper die cavity 3 has a long side portion 36. A first upper material blocking groove 4 is opened on the outer side of the long side portion 36. A second upper material blocking groove 5 is opened on the outer side of the two pre-forging upper die cavities 3 at the ends that are far apart from each other. A first upper positioning groove 6 is opened on the ends that are far apart from each other. A second upper positioning groove 7 is opened on the ends that are close to each other.

[0077] The lower die pre-forging cavity includes two pre-forging lower die cavities 8 with the same shape. The two pre-forging lower die cavities 8 correspond one-to-one with the two pre-forging upper die cavities 3. Each pre-forging lower die cavity 8 has a large plane 33 for forming the long side of the blank and a small plane 34 for forming the short side of the blank. The large plane 33 and the small plane 34 are arranged in a V-shape. A first lower positioning groove 11 is opened on the large plane 33, and a second lower positioning groove 35 is opened on the small plane 34. A first lower blocking groove 9 corresponding to the first upper blocking groove 4 is opened on the outer side of the large plane 33. A second lower blocking groove 10 corresponding to the second upper blocking groove 5 is opened on the outer side of the two pre-forging lower die cavities 8 at the ends that are far apart from each other.

[0078] The final forging die cavity includes the upper die final forging cavity located in the upper forging die 1 and the lower die final forging cavity located in the lower forging die 2.

[0079] The upper die forging cavity includes two identical upper die cavities 12, which are symmetrically arranged about the center of the upper die forging cavity; each upper die cavity 12 has a stepped hole 13.

[0080] The stepped hole 13 is designed to hold the clamping post on the blank. The design of the stepped hole 13 can squeeze the excess material on the clamping post during the final forging process, preventing the folding defects caused by the excess material from occurring on the working surface of the blank.

[0081] The stepped hole 13 includes a first part and a second part that are interconnected. The diameter of the first part is larger than that of the second part. The first part is closer to the lower forging die 2 than the second part. When the upper forging die 1 is pressed down during forging, the excess material on the clamping column will be pressed and accumulated in the first part, and will not accumulate on the working surface, thus avoiding folding defects on the working plane 16.

[0082] The lower die forging cavity includes two lower die cavities 14 of the same shape. The two lower die cavities 14 are symmetrically arranged about the center of the lower die forging cavity and correspond one-to-one with the two upper die cavities 12.

[0083] Each pre-forging upper die cavity 3 has a short side portion 37, which is arranged in a V-shape with the long side portion 36. A rounded corner 15 is formed at the connection between the short side portion 37 and the long side portion 36. A plane 16 is also formed at the connection between the short side portion 37 and the long side portion 36.

[0084] A rounded corner 15 with a large radius is set at the connection between the short side 37 and the long side 36 to make the material flow more smoothly and avoid forging defects such as large folds and material shortages during forging.

[0085] Due to the special shape of the workpiece blank, a plane 16 is added at the connection between the short side 37 and the long side 36 to make the material flow smoother and improve the problem of coarse grain difference on the working plane 16. This avoids taking a coarse grain layer from the working plane 16 when sampling and testing the workpiece after forging.

[0086] The forging die also includes: a lower spring 17, a lower inner top plate 18, a lower ejector rod 19, a lower outer top plate 20, and a lower ejector pad 21. The lower ejector pad 21, the lower outer top plate 20, and the lower inner top plate 18 are sequentially arranged at the lower end of the forging lower die 2 along the direction close to the upper forging die 1. One end of the lower spring 17 extends into the lower forging die 2, and the other end of the lower spring 17 passes through the lower inner top plate 18 and connects to the lower outer top plate 20. One end of the lower ejector rod 19 abuts against the lower outer top plate 20, and the other end of the lower ejector rod 19 passes through the lower inner top plate 18 and extends into the lower forging die 2. The lower spring 17 is a red spring with a diameter of 25mm and a length of 90mm.

[0087] The lower end of the forging die 2 is also provided with a circular pressure plate. The lower end of the circular pressure plate passes through the lower outer top plate 20 and abuts against the lower end surface of the lower inner top plate 18. The upper end of the circular pressure plate is connected to the forging die 2, which serves to limit the lower inner top plate 18.

[0088] The forging die also includes: an upper spring 22, an upper inner top plate 23, an upper ejector rod 24, an upper outer top plate 25, and an upper ejector pad 26. The upper ejector pad 26, the upper outer top plate 25, and the upper inner top plate 23 are sequentially arranged at the upper end of the forging upper die 1 along the direction close to the lower forging die 2. One end of the upper spring 22 extends into the forging upper die 1, and the other end of the upper spring 22 passes through the upper inner top plate 23 and connects to the upper outer top plate 25. One end of the upper ejector rod 24 abuts against the upper outer top plate 25, and the other end of the upper ejector rod 24 passes through the upper inner top plate 23 and extends into the forging upper die 1. The upper ejector pad 26 is installed on the upper outer top plate 25 by the first screw group 29.

[0089] The forging die also includes a pressure block 27 and a date stamp 28, both of which are disposed within the upper forging die 1, with the pressure block 27 abutting against the date stamp 28. A second screw assembly 30 extends into the pressure block 27 and abuts against the date stamp 28.

[0090] Both step S3 (pre-forging) and step S4 (final forging) require the use of a release agent, which is a water-based graphite release agent. This release agent has the dual functions of lubrication and demolding, and the graphite component can reduce the friction between the mold and the material, thereby reducing forging stress.

[0091] The forging process of forging dies is as follows:

[0092] First, spray a release agent onto the two pre-forging lower cavities 8; then place a raw material bar on the two pre-forging lower cavities 8. Because there is an angle between the large plane 33 and the small plane 34, the first lower positioning groove 11 and the second lower positioning groove 35 respectively hold the two sides of the raw material bar, so that the raw material bar is stably placed between the large plane 33 and the small plane 34, preventing the raw material bar from rotating.

[0093] As the forging die 1 moves downwards, the end of the two pre-forging upper die cavities 3 that is close to each other is higher than the end that is far apart. Therefore, the second positioning groove first contacts the raw material bar and is stuck on the raw material bar. The two second positioning grooves respectively hold the two sides of the raw material bar. At this time, the forging die 1 continues to move downwards. The middle of the raw material bar is compressed, and the two ends will tilt upwards. Then, the two ends of the raw material bar are respectively stuck on the first upper positioning groove 6, which plays a role in assisting the positioning of the raw material bar and further preventing the raw material bar from rotating. During the pre-forging process, the raw material bar moves towards the short side of the pre-forging lower die cavity 8 and the pre-forging under the combined action of the first upper blocking groove 4, the second upper blocking groove 5, the first lower blocking groove 9, and the first lower blocking groove 9. The short side of the upper die cavity 3 flows; after the pre-forging is completed, the upper ejector pad 26 drives the upper outer ejector plate 25 and the upper inner ejector plate 23 to move downward, which in turn causes the upper ejector rod 24 to move downward and eject the pre-forged blank from the pre-forging upper die cavity 3; at the same time, the lower ejector pad 21 drives the lower outer ejector plate 20 and the lower inner ejector plate 18 to move upward, which in turn causes the lower ejector rod 19 to move upward and eject the pre-forged blank from the pre-forging lower die cavity 8; the forging upper die 1 moves upward, and the upper inner ejector plate 23 drives the upper ejector pad 26, the upper outer ejector plate 25 and the upper ejector rod 24 to reset under the action of the upper spring 22, and the lower inner ejector plate 18 drives the lower ejector pad 21, the lower outer ejector plate 20 and the lower ejector rod 19 to reset under the action of the lower spring 17;

[0094] Then, the robotic arm clamps the blank after demolding from the pre-forging die cavity and places it on the final forging lower die cavity 14. The forging upper die 1 moves downward, and the final forging upper die cavity 12 and the final forging lower die cavity 14 close to perform final forging of the blank. After the final forging is completed, the upper ejector pad 26 drives the upper outer ejector plate 25 and the upper inner ejector plate 23 to move downward, thereby causing the upper ejector rod 24 to move downward and eject the final forged blank from the final forging upper die cavity 12. At the same time, the lower ejector pad 21 drives the lower outer ejector plate 25 to move downward. The top plate 20 and the lower inner top plate 18 move upward, which in turn causes the lower ejector rod 19 to move upward, ejecting the final forged blank from the final forging lower die cavity 14; the forging upper die 1 moves upward, and the upper inner top plate 23, under the action of the upper spring 22, drives the upper ejector pad 26, the upper outer top plate 25 and the upper ejector rod 24 to reset; the lower inner top plate 18, under the action of the lower spring 17, drives the lower ejector pad 21, the lower outer top plate 20 and the lower ejector rod 19 to reset; thus completing the forging process.

[0095] Examples 2 to 9

[0096] The solution aging process parameters of Examples 1 to 9 are shown in Table 1. The aluminum alloy battery pack brackets prepared in Examples 1 to 9 were tested for tensile strength, yield strength and elongation, and the test results are shown in Table 2.

[0097] Table 1 Solution treatment and aging process parameters for Examples 1 to 9

[0098]

[0099] Table 2 Test Results of Examples 1 to 9

[0100]

[0101] As shown in Table 2, the aluminum alloy battery pack brackets prepared in Examples 1 to 9 all meet the production requirements in terms of tensile strength, yield strength, and elongation.

[0102] In summary, the manufacturing process and design of this aluminum alloy battery pack bracket are reasonable and have the following advantages:

[0103] (1) The present invention optimizes the solid solution aging process, reduces the forming stress, thereby reducing the stress damage and stress residue area of ​​the workpiece, and ultimately reduces the growth degree of coarse grains in the stress area, which is suitable for coarse grains in thin-walled parts;

[0104] (2) By setting the first upper blocking groove 4 and the first lower blocking groove 9, the metal flow direction can be changed, which is conducive to the material flowing from the long side to the short side; by setting the second upper blocking groove 5 and the second lower blocking groove 10, the metal flow direction can be changed, which can prevent the material from flowing to both ends instead of flowing to the short side during the pre-forging process, and further improve the material utilization rate.

[0105] (3) By adopting the design that the center of the two pre-forging upper die cavities 3 and the center of the upper die pre-forging cavity are offset in the left and right directions, it can be ensured that the raw material bar will not deflect during the pre-forging process, and the process of chamfering the raw material bar is also saved. By setting the second upper positioning groove 7, the first lower positioning groove 11 and the second lower positioning groove 35, the raw material bar can be accurately positioned. The first upper positioning groove 6 is set at both ends. During the pressing process of the forging upper die 1, the two ends of the raw material bar are pressed and can still be stuck in the first upper positioning groove 6, which plays a role in assisting the positioning of the raw material bar.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A manufacturing process for an aluminum alloy battery pack bracket, characterized in that: The aluminum alloy battery pack bracket includes a long plate portion (1-1) and a short plate portion (1-2) connected to each other, and the long plate portion (1-1) and the short plate portion (1-2) are arranged in a V-shape; the upper and lower surfaces of the long plate portion (1-1) are respectively provided with a number of small protrusions (1-3), the connection between the long plate portion (1-1) and the short plate portion (1-2) is set as a rounded corner connection, and a large protrusion (1-4) is provided in the middle of the connection; the thickness of the thinnest part (A) of the aluminum alloy battery pack bracket is 5-7mm; The manufacturing process specifically includes the following steps: Step S1: Feeding the material to obtain bar stock; Step S2: Heating the mold; the forging mold is heated. Step S3: Pre-forging. The bar obtained in step S1 is placed into a heated pre-forging mold and pre-forged to form an aluminum alloy battery pack bracket pre-forged part. Before pre-forging, the temperature of the bar is 520-560℃. Step S4: Final forging. The aluminum alloy battery pack bracket pre-forging obtained in step S3 is placed into a heated final forging mold and forged to obtain the final forging of the aluminum alloy battery pack bracket. Step S5: Trim the edges. Place the final forging of the aluminum alloy battery pack bracket obtained in step S4 into the trimming device to remove the waste edges and obtain the intermediate product of the aluminum alloy battery pack bracket. Step S6: Water cooling. The intermediate aluminum alloy battery pack bracket obtained in step S5 is cooled in water. The temperature of the intermediate aluminum alloy battery pack bracket before water immersion is ≥400℃. Step S7, solution treatment and aging: The intermediate aluminum alloy battery pack bracket after step S6 is subjected to solution treatment and aging treatment in sequence to obtain the heat-treated aluminum alloy battery pack bracket; wherein, the solution treatment process is: solution temperature is 515~535℃, solution time is 80~120min, and the aging treatment process is: aging temperature is 165~185℃, aging time is 6~10h; Step S8: Inspect the packaging; In this process, the pre-forging step S3 and the final forging step S4 are operated on the same forging die. The forging die includes an upper forging die (1) and a lower forging die (2) located directly below the upper forging die (1). The upper forging die (1) and the lower forging die (2) are provided with a pre-forging die cavity and a final forging die cavity for forging blanks. The pre-forging die cavity includes an upper die pre-forging cavity located on the upper forging die (1) and a lower die pre-forging cavity located on the lower forging die (2). The upper die pre-forging cavity includes two pre-forging upper die cavities (3) of the same shape. The two pre-forging upper die cavities (3) are symmetrically arranged about the center of the upper die pre-forging cavity. The centers of the two pre-forging upper die cavities (3) are located on both sides of the center of the upper die pre-forging cavity. The lower die pre-forging cavity includes two pre-forging lower die cavities (8) of the same shape. The two pre-forging lower die cavities (8) correspond one-to-one with the two pre-forging upper die cavities (3). Each pre-forging lower die cavity (8) has a large plane (33) for forming the long side of the blank and a small plane (34) for forming the short side of the blank. The large plane (33) and the small plane (34) are arranged in a V-shape. A first lower positioning groove (11) is opened on the large plane (33), and a second lower positioning groove (35) is opened on the small plane (34). Each of the pre-forging upper die cavities (3) has a short side (37) and a long side (36), the short side (37) and the long side (36) are arranged in a V-shape, and the connection between the short side (37) and the long side (36) is formed with a rounded corner (15). A plane (16) is also formed at the connection between the short side (37) and the long side (36). A first upper material blocking groove (4) is provided on the outer side of the long side (36), a second upper material blocking groove (5) is provided on the outer side of the two pre-forging upper cavities (3) at the ends that are far apart from each other, a first upper positioning groove (6) is provided on the ends that are far apart from each other, and a second upper positioning groove (7) is provided on the ends that are close to each other.

2. The method of manufacturing an aluminum alloy battery pack support of claim 1, wherein: In step S3, the deformation of the pre-forged aluminum alloy battery pack bracket from the bar stock to the pre-forged aluminum alloy battery pack bracket is 86%; in step S4, the deformation of the pre-forged aluminum alloy battery pack bracket to the final forged aluminum alloy battery pack bracket is 15%.

3. The method of manufacturing an aluminum alloy battery pack support of claim 1, wherein: The final forging die cavity includes an upper die final forging cavity located in the upper forging die (1) and a lower die final forging cavity located in the lower forging die (2). The upper die final forging cavity includes two final forging upper die cavities (12) with the same shape. The two final forging upper die cavities (12) are symmetrically arranged about the center of the upper die final forging cavity. Each final forging upper die cavity (12) has a stepped hole (13). The lower die forging cavity includes two lower die cavities (14) with the same shape. The two lower die cavities (14) are symmetrically arranged about the center of the lower die forging cavity and correspond one-to-one with the two upper die cavities (12).

4. The manufacturing process of an aluminum alloy battery pack bracket according to claim 1, characterized in that: The outer side of the large plane (33) is provided with a first lower blocking groove (9) corresponding to the first upper blocking groove (4), and the outer side of the two pre-forging lower die cavities (8) that are far apart from each other is provided with a second lower blocking groove (10) corresponding to the second upper blocking groove (5).

5. The method of manufacturing an aluminum alloy battery pack support of claim 1, wherein: The forging die further includes: a lower spring (17), a lower inner top plate (18), a lower ejector rod (19), a lower outer top plate (20), and a lower ejector pad (21). The lower ejector pad (21), the lower outer top plate (20), and the lower inner top plate (18) are arranged sequentially at the lower end of the forging lower die (2) in a direction close to the forging upper die (1). One end of the lower spring (17) extends into the forging lower die (2), and the other end of the lower spring (17) passes through the lower inner top plate (18) and is connected to the lower outer top plate (20). One end of the lower ejector rod (19) abuts against the lower outer top plate (20), and the other end of the lower ejector rod (19) passes through the lower inner top plate (18) and extends into the forging lower die (2).

6. The method of manufacturing an aluminum alloy battery pack support of claim 1, wherein: The forging die further includes: an upper spring (22), an upper inner top plate (23), an upper ejector rod (24), an upper outer top plate (25), and an upper ejector pad (26). The upper ejector pad (26), the upper outer top plate (25), and the upper inner top plate (23) are arranged sequentially at the upper end of the forging upper die (1) in the direction close to the lower forging die (2). One end of the upper spring (22) extends into the upper forging die (1), and the other end of the upper spring (22) passes through the upper inner top plate (23) and is connected to the upper outer top plate (25). One end of the upper ejector rod (24) abuts against the upper outer top plate (25), and the other end of the upper ejector rod (24) passes through the upper inner top plate (23) and extends into the upper forging die (1).

7. The method of manufacturing an aluminum alloy battery pack support of claim 1, wherein: Both the pre-forging in step S3 and the final forging in step S4 require the use of a release agent, which is a water-based graphite release agent.

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