A stirring friction tunnel forming device and method for equal-height internal flow channels

Abstract

This invention relates to a stirring friction tunnel forming apparatus and method for equal-height internal flow channels, belonging to the field of stirring friction tunnel forming technology. It includes a rotating tool component and a non-rotating tool component, with the rotating tool component located inside the non-rotating tool component. A guide groove is machined on the lower part of the non-rotating tool component. Through the design of the stirring friction tunnel forming tool, this invention can simultaneously achieve equal-height internal flow channel forming, smooth inner wall forming of the internal flow channel, no excess surface height, and continuously adjustable internal flow channel height. Furthermore, it requires only a single process to complete the high-quality processing of the internal flow channel, featuring simple process, low production cost, high processing efficiency, and excellent internal flow channel performance.

Description

Technical Field

[0001] This invention relates to a stirring friction tunnel forming device and method, belonging to the field of stirring friction tunnel forming technology. Background Technology

[0002] In new energy electric vehicles, the cooling system mainly includes cooling components such as the drive motor, vehicle controller, and DC / DC converter, as well as cooling the power battery and on-board charger. Currently, electric vehicle power batteries are primarily temperature-sensitive lithium-ion batteries. The temperature environment within the battery pack significantly impacts the reliability, lifespan, and performance of the cells, making battery thermal management a crucial guarantee for the operation of new energy vehicles. The liquid cooling plate is a core component of the battery thermal management liquid cooling module. Excess heat generated during battery operation is transferred through contact between the battery or module and the surface of the plate-shaped aluminum device, and is ultimately carried away by the cooling medium flowing through the internal channels of the device. The technical requirements for liquid cooling plates generally include five core requirements: first, high heat dissipation power; second, high reliability, ensuring the cold plate is sealed; third, precise heat dissipation design to avoid excessive temperature differences within the system; fourth, strict control of the cold plate weight to avoid significantly reducing the system's energy density; and fifth, controllable cost.

[0003] Currently, there are three main methods for manufacturing internal flow channels on aluminum sheet devices: The first method combines grooving and cover plate to create the internal flow channel, which requires two steps of "milling + welding" to achieve tunnel forming. This is the most commonly used method, but its process is relatively complex and is prone to corrosion leakage due to the corrosion potential difference between the cast substrate and the forged cover plate. The second method is the embedded tube process, which involves pressing a copper tube into a pre-made groove in the aluminum sheet device to create the internal flow channel. It should be noted that this method inevitably reduces material utilization and increases the overall structural weight of the device. The third method is friction stir channeling (FST) technology, which uses a high-speed rotating FST tool to penetrate the aluminum sheet device. Through the threaded drainage groove design on the tool surface, the thermoplasticized aluminum material along a specific path is discharged outward, while the upper surface of the workpiece is welded together, forming a continuous internal flow channel inside the workpiece. This method has good application prospects in terms of internal weight reduction and high-speed flow channel forming.

[0004] However, this method still faces the following four technical bottlenecks that urgently need to be overcome:

[0005] 1. The shape of the inner flow channel depends on the flow guiding design of the forming tool. Therefore, the two sides of the inner flow channel usually have inconsistent heights, which is not conducive to the layout planning of the inner flow channel prepared by friction stir tunnel forming in aluminum devices.

[0006] 2. Due to the traditional end face design of forming tools, the lower wall of the inner flow channel usually has a relatively obvious rounded corner and a large roughness, which leads to a significant increase in the flow resistance of the cooling medium.

[0007] 3. The aluminum that must be discharged to form the internal flow channel usually accumulates on the surface of aluminum sheet components, requiring secondary machining to remove it, which increases the complexity of the process;

[0008] 4. The size and height of the internal flow channel are directly dependent on the geometry of the forming tool, and the height and position of the flow channel in aluminum sheet devices are difficult to continuously control.

[0009] Therefore, there is an urgent need to propose a stirring friction tunnel forming device and method with equal-height internal flow channels to solve the above-mentioned technical problems. Summary of the Invention

[0010] To overcome the aforementioned technical deficiencies, the present invention aims to provide a stirring friction tunnel forming apparatus and method for an equal-height internal flow channel. A brief overview of the invention is given below to provide a basic understanding of certain aspects thereof. It should be understood that this overview is not an exhaustive summary of the invention. It is not intended to identify key or essential parts of the invention, nor is it intended to limit the scope of the invention.

[0011] The technical solution of the present invention:

[0012] A stirring friction tunnel forming device with an equal-height internal flow channel includes a rotating tool component and a non-rotating tool component. The rotating tool component is located inside the non-rotating tool component, and a flow guide groove is machined on the lower part of the non-rotating tool component.

[0013] Preferably, the non-rotating tool component includes a second transition section and a shoulder section. The lower sidewall of the second transition section is machined with discharge holes, and a plurality of discharge holes are circumferentially equidistant. The bottom of the second transition section has a shoulder section, and a guide groove is machined on the shoulder section.

[0014] Preferably, it further includes a non-rotating bushing component and a mating connector. The non-rotating bushing component is connected to the non-rotating tool component through the mating connector. A clearance hole is machined in the middle of the lower side wall of the non-rotating bushing component. A plurality of first assembly holes are machined on the lower side wall of the non-rotating bushing component. The non-rotating bushing component is connected to the non-rotating stator part of the spindle of a friction stir welding machine, a CNC milling machine, or a CNC machining center.

[0015] Preferably, the non-rotating tool component further includes a clamping and positioning part and a stud connection part. The connection part between the clamping and positioning part and the second transition part is provided with a stud connection part. A plurality of second assembly holes are machined on the stud connection part. A spring is provided between the stud connection part of the non-rotating tool component and the lower side wall of the non-rotating bushing component. The cooperating connector passes through the second assembly holes and connects with the first assembly hole.

[0016] Preferably, the rotary tool component includes a clamping part, a first transition part, and a stirring pin part, which are connected sequentially from top to bottom. The lower side of the first transition part is provided with a necking area, the diameter of which is smaller than the outer diameter of the stirring pin part. The lower end of the stirring pin part extends out. The clamping part is connected to the spindle rotating rotor part of a friction stir welding machine, a CNC milling machine, or a CNC machining center.

[0017] Preferably, the stirring needle includes a threaded area and a root-cleaning area. The root-cleaning area is a rotationally symmetric body with a cutting groove. The root-cleaning area is located below the threaded area, and the necking area is located above the threaded area.

[0018] Preferably, the side of the clamping part is machined with a milled plane, and the connection between the first transition part and the clamping part is provided with a positioning boss.

[0019] A method for forming a friction-stirring tunnel with an equal-height internal flow channel, using the aforementioned friction-stirring tunnel forming device with an equal-height internal flow channel, includes the following steps:

[0020] S1: Prepare components: Polish and clean the components;

[0021] S2: Friction stirring tunnel forming includes the following steps:

[0022] S21: The rotating tool component rotates at a rotational speed ω and penetrates into the device. The penetration process continues until the shoulder of the shaft contacts the upper surface of the device.

[0023] S22: The device then moves along the desired inner flow path at a speed v; during the movement, the material is lifted by the threaded area of ​​the stirring needle and converges towards the constriction area and is discharged from the discharge hole, thus forming a continuous inner flow channel.

[0024] S23: The rotating tool part and the non-rotating tool part are raised synchronously to complete the machining of the entire inner flow channel;

[0025] S3: Inner channel cleaning: A sodium hydroxide aqueous solution mixed with silicon carbide particles is continuously passed into the processed inner channel to further polish the inner channel wall.

[0026] Preferably, in S22, the equal-height inner flow channel is formed by the guide groove located on the return side of the shaft shoulder;

[0027] By milling the lower surface of the inner flow channel through the root clearing area of ​​the stirring needle end face, the formation of lower wall fillet and high roughness is suppressed;

[0028] During the friction stirring tunnel forming process, the discharged and conveyed material gathers in the necking area and is then discharged from the discharge hole, avoiding the accumulation of excess material on the surface of the aluminum plate device to form excess height.

[0029] When the height of the inner flow channel needs to be continuously adjustable, the disc spring is compressed, causing the stirring needle to protrude a greater distance from the shoulder, thereby adjusting the height of the inner flow channel.

[0030] Preferably, in S21, if the spindle adopts a counterclockwise rotation working mode, the thread in the threaded area should be a left-hand thread; if the spindle adopts a clockwise rotation working mode, the thread in the threaded area should be a right-hand thread.

[0031] The present invention has the following beneficial effects:

[0032] This invention, through the design of a stirring friction tunnel forming tool, can simultaneously achieve equal-height inner flow channel forming, smooth inner wall forming of the inner flow channel, no excess surface height, and continuously adjustable inner flow channel height. Moreover, it can complete the high-quality processing of the inner flow channel in a single process, and has the characteristics of simple process, low production cost, high processing efficiency, and excellent inner flow channel performance.

[0033] This invention has a wide range of applications. Different structural dimensions can be selected according to the shape characteristics of aluminum sheet devices. Targeted liquid-cooled tunnel forming can be carried out on different materials in different fields, which can significantly improve the effectiveness of different fields and their different heat dissipation requirements. Attached Figure Description

[0034] Figure 1 This is a cross-sectional view of a stirring friction tunnel forming device with an equal-height internal flow channel;

[0035] Figure 2 A schematic diagram of a rotating tool component of a friction stirring tunnel forming device with equal-height internal flow channels;

[0036] Figure 3 This is a schematic diagram of a non-rotating tool component of a friction stirring tunnel forming device with equal-height internal flow channels;

[0037] Figure 4 A bottom view of a non-rotating tool component of a friction stirring tunnel forming device with equal-height internal flow channels;

[0038] Figure 5 This is a schematic diagram illustrating the technical characteristics of a stirring friction tunnel forming method with an equal-height internal flow channel.

[0039] In the figure, 1-rotary tool component, 101-clamping part, 10101-side milling plane, 102-first transition part, 10201-axial positioning boss, 10202-neck area, 103-stirring needle part, 10301-thread area, 10302-root cleaning area;

[0040] 2-Non-rotating tool component, 201-Clamping and positioning part, 202-Stud connection part, 20201-Second assembly hole, 203-Second transition part, 20301-Discharge hole, 204-Shoulder part, 20401-Guide groove;

[0041] 3-Non-rotating shoulder component, 301-First mounting hole;

[0042] 4-Spring; 5-Matching connector; 6-Component; 7-Discharged excess material; 8-Inner flow channel. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is described below with reference to specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0044] Specific implementation method one: Combining Figure 1 and 3 This embodiment describes a friction stirring tunnel forming device for an equal-height internal flow channel, comprising a rotating tool component 1 and a non-rotating tool component 2. The rotating tool component 1 and the non-rotating tool component 2 are coaxially arranged, with the rotating tool component 1 located inside the non-rotating tool component 2. A guide groove 20401 is machined on the lower part of the non-rotating tool component 2, and the guide groove 20401 communicates with the inner cavity of the non-rotating tool component 2. This invention can realize friction stirring tunnel forming with an equal-height internal flow channel, while also achieving smooth inner wall forming, no excess surface height, and continuously adjustable internal flow channel height. It will effectively promote the application and transformation of friction stirring tunnel forming technology, realizing its key applications in engineering and technical fields such as new energy vehicles and aerospace.

[0045] Specific Implementation Method Two: Combining Figure 1-4This embodiment describes a friction stirring tunnel forming device for an equal-height internal flow channel. The non-rotating tool component 2 includes a second transition portion 203 and a shoulder portion 204. The second transition portion 203 is a frustum-shaped section that is wider at the top and narrower at the bottom, which ensures strength, increases wall thickness, avoids scratches, and provides sufficient space for adding cooling structures to the flow channel. The lower part of the second transition portion 203 or the side wall of the shoulder portion 204 is machined with radial discharge holes 20301, and the middle part of the shoulder portion 204 is machined with a central section. The device has a through hole and several discharge holes 20301 arranged circumferentially at equal intervals. The number of discharge holes is four to six. The discharge holes are connected to the inner cavity of the non-rotating tool part 2. The bottom of the second transition part 203 has a shoulder part 204. An axially offset guide groove 20401 is machined on the shoulder part 204. The guide groove 20401 can be located on the side wall of the central through hole. During operation, the guide groove 20401 should be set on the rear side of the device, which is the return side. The front side of the device is the forward side, and the device moves forward.

[0046] Specific implementation method three: Combining Figure 1-4 This embodiment describes a friction stir tunnel forming device with an equal-height internal flow channel, which further includes a non-rotating bushing component 3 and a mating connector 5. The non-rotating bushing component 3 is connected to the non-rotating tool component 2 via the mating connector 5. An axial clearance hole is machined in the middle of the lower side wall of the non-rotating bushing component 3. Several circumferentially equidistant first assembly holes 301 are machined on the lower side wall of the non-rotating bushing component 3. The diameter of the clearance hole is larger than the outer diameter of the clamping and positioning part 201. The clearance hole can prevent the transition part 203 from colliding with it, increase the adjustment range of the non-rotating tool component, and the clearance hole is coaxially arranged with the transition part 203, which can also limit radial displacement. The rotating tool component 1 passes through the clearance hole. The non-rotating bushing component 3 is connected to the non-rotating stator part of the spindle of a friction stir welding machine, a CNC milling machine, or a CNC machining center.

[0047] Specific implementation method four: Combination Figure 1-4 This embodiment describes a friction stirring tunnel forming apparatus for an equal-height internal flow channel. The non-rotating tool component 2 further includes a clamping and positioning part 201 and a stud connecting part 202, as shown below. Figure 1In the middle, the clamping and positioning part 201 and the transition part 203, arranged coaxially, form the sidewall of the non-rotating tool component 2. A stud connection part 202 is provided on the outer side of the connection between the clamping and positioning part 201 and the second transition part 203. A plurality of second assembly holes 20201 are machined on the stud connection part 202, which are circumferentially equidistant. The clamping and positioning part 201, the stud connection part 202, the transition part 203, and the shoulder part 204 are integrally formed. A funnel-shaped inner cavity is machined on the inner side of the sidewall of the non-rotating tool component 2. The lower part of the funnel-shaped inner cavity is connected to the middle through hole to form the inner cavity of the non-rotating tool component 2. A spring 4, which is a disc spring, is fitted on the outer side of the clamping and positioning part 201. A spring 4 is provided between the stud connection 202 of component 2 and the lower side wall of the non-rotating bushing component 3. The stud connection 202 is an annular disc, and the mating connector 5 passes through the second assembly hole 20201 and connects to the first assembly hole 301. The mating connector 5 is a bolt, the first assembly hole 301 is a threaded hole, and the second assembly hole 20201 is a through hole. The bolt is slidably connected to the through hole and threadedly connected to the first assembly hole 301. The lower part of the mating connector 5 presses against the stud connection 202, and the spring 4 is compressed. This ensures the stability of the non-rotating tool component 2 during operation, provides shock absorption, and can also adjust the relative position of the non-rotating tool component 2 and the non-rotating bushing component 3.

[0048] Specific Implementation Method Five: Combining Figure 1-4 This embodiment describes a friction stir tunnel forming device with an equal-height internal flow channel. The rotating tool component 1 includes a clamping part 101, a first transition part 102, and a stirring pin part 103. The clamping part 101, the first transition part 102, and the stirring pin part 103 are integrally machined sequentially from top to bottom. A necking region 10202 is provided on the lower side of the first transition part 102. The diameter of the necking region 10202 is slightly smaller than the outer diameter of the stirring pin part 103. The necking region 10202 forms a large gap with the inner wall of the cavity, which can temporarily store materials. The necking region 10202 is correspondingly arranged with the discharge hole 20301. The lower end of the stirring pin part 103 extends out from the inner cavity of the non-rotating tool component 2. The clamping part 101 is connected to the spindle rotating rotor part of a friction stir welding machine, a CNC milling machine, or a CNC machining center.

[0049] Specific Implementation Method Six: Combination Figure 1-4 This embodiment describes a stirring friction tunnel forming device with an equal-height internal flow channel. The stirring needle 103 includes a threaded region 10301 and a root-cleaning region 10302. The root-cleaning region 10302 is a rotationally symmetric body with a cutting groove. The root-cleaning region 10302 is located below the threaded region 10301, and the necking region 10202 is located above the threaded region 10301. The cutting groove is a triangular notch.

[0050] Specific implementation method seven: Combination Figure 1-4This embodiment describes a stirring friction tunnel forming device with an equal-height internal flow channel. The clamping part 101 has a milled plane 10101 on its side. The first transition part 102 is connected to the clamping part 101 with a positioning boss 10201. The upper part of the first transition part 102 is a cylinder, the middle part is a frustum, the connection between the cylinder and the frustum is chamfered, and the lower part is a cylindrical necking area 10202. The acute angle between the side of the frustum and the vertical plane (the axis of the device is located on the vertical plane) is greater than the acute angle between the inner wall of the funnel-shaped inner cavity of the non-rotating tool part 2 and the vertical plane, which facilitates the movement of the rotating tool part 1 within the non-rotating tool part.

[0051] Specific implementation method eight: Combination Figure 1-5 This embodiment describes a method for forming a friction-stirred tunnel with an equal-height internal flow channel. The method employs a friction-stirred tunnel forming apparatus (hereinafter referred to as the apparatus) and includes the following steps:

[0052] S1: Prepare the component: Grind and clean component 6. That is, prepare component 6, which is an aluminum plate component, according to the actual sample requirements. Use a wire brush to mechanically grind and clean the surface of the component with acetone, and use rigid tooling to clamp component 6.

[0053] S2: Friction stirring tunnel forming includes the following steps:

[0054] S21: Rotary tool component 1 and non-rotary tool component 2 are coaxially mounted. Rotary tool component 1 rotates at a specific rotation speed ω. Rotary tool component 1 is inserted into device 6 from the top, side, bottom, etc. Both (rotary and non-rotary tool components) are inserted into device 6 in the inner flow channel to be processed simultaneously. The insertion process continues until the shoulder 204 contacts the upper surface of device 6.

[0055] S22: Subsequently, the two move synchronously along the desired inner flow path at a specific travel speed v; during the travel, the material generated by the cutting of device 6 is gathered near the necking area 10202 under the lifting action of the threaded area 10301 of the stirring needle 103 and discharged from the discharge hole 20301. The shoulder 204 then flattens the material to form a continuous and through inner flow channel; the material is thermoplasticized aluminum.

[0056] S23: After the inner flow channel is processed, the rotating tool part 1 and the non-rotating tool part 2 are raised synchronously to complete the processing of the inner flow channel (tunnel) on the entire device;

[0057] S3: Inner channel cleaning: A 10% sodium hydroxide aqueous solution mixed with silicon carbide particles (particle size 1-20μm) is continuously passed into the processed inner channel at a certain speed to further polish the inner channel wall, improve the smoothness of the inner channel wall, and reduce the flow resistance.

[0058] This invention has a wide range of applications. Different structural dimensions can be selected according to the shape characteristics of aluminum sheet devices. Targeted liquid-cooled tunnel forming can be carried out on different materials in different fields, which can significantly improve the effectiveness of different fields and their different heat dissipation requirements.

[0059] Specific Implementation Method Nine: Combining Figure 1-5 This embodiment describes a stirring friction tunnel forming method for an equal-height internal flow channel. In S22, the method for forming an equal-height internal flow channel is to increase the material extrusion speed on the return side of the device by using the offset guide groove 20401 located on the return side of the shoulder 204, thereby ensuring the consistency of the discharge volume on the forward and backward sides and achieving equal-height internal flow channel / tunnel forming.

[0060] The method for smoothing the inner wall surface is as follows: the lower surface of the inner flow channel is milled by the root clearing area 10302 of the end face of the stirring needle 103, thereby suppressing the formation of rounded corners and high roughness of the lower wall surface of the inner flow channel.

[0061] The method to eliminate excess height on the surface is as follows: during the friction stirring tunnel forming process, the discharged and conveyed material gathers in the necking area 10202 and is then discharged from the discharge hole 20301, thus avoiding the accumulation of excess material 7 (material) on the surface of the aluminum plate device 6 to form excess height.

[0062] The method for continuously adjusting the height of the inner flow channel is as follows: when it is necessary to continuously adjust the height of the inner flow channel, the stirring needle 103 can be driven to move up and down by the active up and down movement of the main shaft. The shoulder 204 remains in a constant position under the action of the device 6. The force on the spring 4 changes, thereby changing the length of the stirring needle 103 extending out of the shoulder 204. When moving up, the extension length becomes shorter, and when moving down, the extension length becomes longer, thereby adjusting the height of the inner flow channel.

[0063] This invention, through the design of a stirring friction tunnel forming tool, can simultaneously achieve equal-height inner flow channel forming, smooth inner wall forming, no excess surface height, and continuously adjustable inner flow channel height. Moreover, it can complete the high-quality processing of the inner flow channel in a single process, and has the characteristics of simple process, low production cost, high processing efficiency, and excellent inner flow channel performance.

[0064] Specific Implementation Method Ten: Combining Figure 1-5This embodiment describes a method for forming a friction-stirred tunnel with an equal-height internal flow channel. In step S21, if the main shaft operates in a counter-clockwise rotation mode (i.e., the rotating tool component 1 rotates counter-clockwise), the thread in the threaded area 10301 should be a left-hand thread; if the main shaft operates in a clockwise rotation mode (i.e., the rotating tool component 1 rotates clockwise), the thread in the threaded area 10301 should be a right-hand thread. The thread adopts a single-start or multi-start triangular thread or trapezoidal thread structure with a pitch of 0.5 to 3.0 mm.

[0065] Example 1:

[0066] like Figure 1-5 A method for forming a friction-stirring tunnel with an equal-height internal flow channel, comprising a friction-stirring tunnel forming device with an equal-height internal flow channel, including a rotating tool component 1, a non-rotating tool component 2, a non-rotating bushing component 3, a spring 4, and a mating connector 5, wherein the mating connector is a fixing bolt and the spring is a disc spring.

[0067] The rotary tool component 1 includes a clamping part 101, a first transition part 102, and a stirring pin part 103. The clamping part 101 is used to connect with the rotary spindle rotor part of machining equipment including but not limited to friction stir welding machines, CNC milling machines, and CNC machining centers, and has a side milled surface 10101 for side-fixed clamping. The first transition part 102 is used to connect the clamping part 101 and the stirring pin part 103, and has an axial positioning boss 10201 for axial positioning with the spindle rotor part, and a necking area 10202 for collecting and discharging the thermoplasticized aluminum material (material) conveyed upward by the stirring pin part. The diameter of the necking area 10202 is slightly smaller than the diameter of the stirring pin part 103 by 0.3 to 1 mm. 5mm, so as to facilitate the accumulation of thermoplastic aluminum to suppress the formation of surface excess height, and to avoid the excessive concentration of aluminum causing the rotating tool part 1 to be subjected to excessive torque and break; the stirring needle part 103 is divided into a threaded area 10301 and a root cleaning area 10302. The threaded area 10301 is used to discharge material upward during the friction stirring tunnel forming process to form an inner flow channel structure. The root cleaning area 10302 is a section of the end face of the stirring needle part 103 with a height of 0.5 to 2.0mm and has 2 to 6 evenly distributed cutting slots. It is used to mill the lower wall of the inner flow channel during the friction stirring tunnel forming process, thereby avoiding the formation of the root (the junction of the inner flow channel side wall and the lower wall) rounded corner and the high roughness structure of the lower wall surface;

[0068] like Figure 2 Thread section 10301: If the spindle adopts a counterclockwise rotation working mode, the thread should be a left-hand thread; if the spindle adopts a clockwise rotation working mode, the thread should be a right-hand thread; the thread adopts a single-start or multi-start triangular thread or trapezoidal thread structure, with a pitch of 0.5 to 3.0 mm;

[0069] The non-rotating tool component 2 includes a clamping and positioning part 201, a stud connecting part 202 (stud fixing part), a second transition part 203, and a shoulder part 204. The clamping and positioning part 201 is used to connect with the non-rotating bushing component 3 and ensures their concentricity through circumferential positioning. The stud connecting part 202 has 4 to 6 evenly distributed through holes 20201, which connect and lock the non-rotating tool component 2 and the non-rotating bushing component 3 via bolts. The transition part 203 has 2 evenly distributed through holes 20201. Six discharge holes 20301 are positioned at the same height as the necking area 10202 of the transition section of the rotating tool component, and are used to continuously discharge the thermoplasticized aluminum 7 gathered by the necking area 10202; the shoulder 204 is used to roll and backfill the overflowing thermoplasticized aluminum to achieve defect-free welding of the inner flow channel surface. It is provided with an offset guide groove 20401 to balance the problem of uneven height of the inner flow channel caused by the different flow velocities on the forward and return sides during the stirring friction tunnel forming process, thereby achieving the forming of an equal-height inner flow channel;

[0070] like Figure 3 , 4 Offset guide channel 20401: The guide channel 20401 should be set on the return side during the friction stirring tunnel forming process, and its size should be between 0.05 and 0.20 times the width of the inner flow channel.

[0071] The non-rotating bushing component 3 is connected to the non-rotating stator part of the spindle of machining equipment including but not limited to friction stir welding machines, CNC milling machines, and CNC machining centers. Its main function is to fix the non-rotating tool component 2, ensuring that the fixed non-rotating tool component 2 remains stationary during the friction stir tunneling process, and to provide a support surface for the disc spring. The disc spring is located between the non-rotating tool component 2 and the non-rotating bushing component 3. When the height of the inner flow channel needs to be continuously adjustable, the disc spring 4 is compressed by the active up-and-down movement of the spindle, causing the stirring needle 103 to protrude further from the shoulder 204, thereby adjusting the height of the inner flow channel. The fixing bolts are used to connect the non-rotating tool component 2 and the non-rotating bushing component 3 and to determine the maximum limiting distance between them.

[0072] like Figure 1-4 This includes the following steps:

[0073] S1: Prepare aluminum sheet components 6: According to the actual sample requirements, prepare aluminum sheet components 6 with inner flow channels to be processed, use a wire brush to mechanically grind and clean the surface of the components with acetone, and clamp them with rigid tooling.

[0074] S2: Friction Stir Tunneling: Rotary tool component 1 and non-rotary tool component 2 are coaxially mounted. The rotary tool component 1 rotates at a specific high speed ω, and both are simultaneously driven into the aluminum sheet component 6 to be processed into the inner flow channel. The driving process continues until the shoulder 20401 contacts the upper surface of the sheet. Subsequently, both move synchronously along the desired inner flow channel path at a specific travel speed v. During the travel, the thermoplasticized aluminum 7 is lifted by the threaded area 10301 of the stirring needle and converges to the vicinity of the necking area 10202 and is discharged from the discharge hole 20301, thereby forming a continuous and through inner flow channel. After the inner flow channel is processed, the rotary tool component 1 and the non-rotary tool component 2 are lifted synchronously to complete the processing of the entire inner flow channel.

[0075] S3: Inner channel cleaning: A 10% sodium hydroxide aqueous solution mixed with silicon carbide particles (particle size 1-20μm) is continuously passed into the processed inner channel at a certain speed to further polish the inner channel wall, improve the smoothness of the inner channel wall, and reduce the flow resistance.

[0076] like Figure 1 , 3 5. The method for achieving equal-height internal flow channel forming is as follows: by using the offset guide groove 20401 located on the return side of the shoulder 204, the extrusion speed of the thermoplastic aluminum 7 on the return side is increased, thereby ensuring the consistency of the discharge volume on the forward side and the backward side, and achieving equal-height internal flow channel forming.

[0077] like Figure 1 , 2 5. The method for smoothing the inner wall surface is as follows: the lower surface of the inner flow channel is milled by the root clearing area 10302 of the end face of the stirring needle 103 to suppress the formation of the lower wall fillet and high roughness.

[0078] like Figure 1-5 The method to eliminate excess material on the surface is as follows: the material discharged during the friction stirring tunnel forming process gathers in the necking area 10202 and is then discharged from the discharge hole 20301, thus avoiding the accumulation of excess material 7 on the surface of the aluminum plate device 6 to form excess material.

[0079] like Figure 1-5 The method for continuously adjusting the height of the inner flow channel is as follows: when it is necessary to continuously adjust the height of the inner flow channel, the disc spring 4 can be compressed by the active up and down movement of the main shaft, so that the stirring needle 103 protrudes further from the shoulder 204, thereby adjusting the height of the inner flow channel.

[0080] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be permuted and combined. Those skilled in the art can exhaust all possibilities based on the mathematical knowledge of permutation and combination. Therefore, the present invention will not describe the technical solutions after permutation and combination one by one, but it should be understood that the technical solutions after permutation and combination have been disclosed by the present invention.

[0081] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A stirring friction tunnel forming device for an equal-height internal flow channel, characterized in that: It includes a rotary tool component (1) and a non-rotary tool component (2). The rotary tool component (1) is located inside the non-rotary tool component (2). The lower part of the non-rotary tool component (2) is machined with a guide groove (20401), which communicates with the inner cavity of the non-rotary tool component (2). The non-rotating tool component (2) includes a second transition part (203) and a shoulder part (204). The lower side wall of the second transition part (203) is machined with a discharge hole (20301). Several discharge holes (20301) are arranged circumferentially at equal intervals. The bottom of the second transition part (203) has a shoulder part (204). A guide groove (20401) is machined on the shoulder part (204). An axially offset guide groove (20401) is machined on the shoulder part (204). The guide groove (20401) is located on the side wall of the central through hole. During operation, the guide groove (20401) should be set on the rear side of the device. The rear side is the return side, and the front side of the device is the forward side. The device moves forward.

2. The stirring friction tunnel forming device for an equal-height internal flow channel according to claim 1, characterized in that: It also includes a non-rotating bushing component (3) and a mating connector (5). The non-rotating bushing component (3) is connected to the non-rotating tool component (2) through the mating connector (5). The lower side wall of the non-rotating bushing component (3) is machined with a clearance hole. The lower side wall of the non-rotating bushing component (3) is machined with a plurality of first assembly holes (301). The non-rotating bushing component (3) is connected to the non-rotating stator part of the spindle of the friction stir welding machine, CNC milling machine, and CNC machining center.

3. The stirring friction tunnel forming device for an equal-height internal flow channel according to claim 2, characterized in that: The non-rotating tool component (2) further includes a clamping and positioning part (201) and a stud connection part (202). The connection part between the clamping and positioning part (201) and the second transition part (203) is provided with a stud connection part (202). A plurality of second assembly holes (20201) are machined on the stud connection part (202). A spring (4) is provided between the stud connection part (202) of the non-rotating tool component (2) and the lower side wall of the non-rotating bushing component (3). The mating connector (5) passes through the second assembly hole (20201) and connects to the first assembly hole (301).

4. The stirring friction tunnel forming device for an equal-height internal flow channel according to claim 3, characterized in that: The rotating tool component (1) includes a clamping part (101), a first transition part (102), and a stirring needle part (103). The clamping part (101), the first transition part (102), and the stirring needle part (103) are connected sequentially from top to bottom. A necking region (10202) is provided on the lower side of the first transition part (102). The diameter of the necking region (10202) is smaller than the outer diameter of the stirring needle part (103). The lower end of the stirring needle part (103) extends out. The clamping part (101) is connected to the spindle rotating rotor part of the friction stir welding machine, CNC milling machine, and CNC machining center.

5. The stirring friction tunnel forming device for an equal-height internal flow channel according to claim 4, characterized in that: The stirring needle (103) includes a threaded area (10301) and a root clearing area (10302). The root clearing area (10302) is a rotationally symmetrical body with a cutting groove. The root clearing area (10302) is located below the threaded area (10301), and the necking area (10202) is located above the threaded area (10301).

6. The stirring friction tunnel forming device for an equal-height internal flow channel according to claim 5, characterized in that: The clamping part (101) has a milled surface (10101) machined on its side, and a positioning boss (10201) is provided at the connection between the first transition part (102) and the clamping part (101).

7. A method for forming a stirring friction tunnel with an equal-height internal flow channel, characterized in that: The stirring friction tunnel forming apparatus for equal-height internal flow channels according to any one of claims 1-6 includes the following steps: S1: Prepare the components: polish and clean the components (6); S2: Friction stirring tunnel forming includes the following steps: S21: The rotating tool component (1) rotates at a rotational speed ω and inserts into the device (6). The insertion process continues until the shoulder (204) contacts the upper surface of the device (6). S22: The device then moves along the desired inner flow path at a speed v; during the movement, the material is lifted by the threaded area (10301) of the stirring needle (103) and converges towards the constriction area (10202) and is discharged from the discharge hole (20301), thereby forming a continuous inner flow channel. S23: The rotating tool component (1) and the non-rotating tool component (2) are raised synchronously to complete the machining of the entire inner flow channel; S3: Inner channel cleaning: A sodium hydroxide aqueous solution mixed with silicon carbide particles is continuously passed into the processed inner channel to further polish the inner channel wall.

8. The method for forming a stirred friction tunnel with an equal-height internal flow channel according to claim 7, characterized in that: In S22, the equal-height inner flow channel is formed by the guide groove (20401) located on the return side of the shoulder (204); By milling the lower surface of the inner flow channel through the root clearing area (10302) on the end face of the stirring needle (103), the formation of the lower wall fillet and high roughness is suppressed; During the friction stirring tunnel forming process, the discharged material gathers in the necking area (10202) and is then discharged from the discharge hole (20301), thus avoiding the accumulation of the discharged excess material (7) on the surface of the aluminum plate device (6) to form excess height; When the height of the inner flow channel needs to be continuously adjustable, the spring (4) is compressed, causing the stirring needle (103) to protrude a greater distance from the shoulder (204), thereby adjusting the height of the inner flow channel.

9. The method for forming a friction-stirred tunnel with an equal-height internal flow channel according to claim 8, characterized in that: In S21, if the spindle adopts a counterclockwise rotation working mode, the thread in the threaded area (10301) should be a left-hand thread; if the spindle adopts a clockwise rotation working mode, the thread in the threaded area (10301) should be a right-hand thread.

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