A cooling device for a metal additive-subtractive composite manufacturing process

Abstract

The utility model discloses a kind of metal additive-subtractive composite manufacturing process cooling device, it is related to additive-subtractive machining technical field, including cooling device main body, the top of cooling device main body is provided with nozzle module, the middle end of cooling device main body is provided with heat dissipation unit, the inside of the end of cooling device main body is installed with deformation cavity;Multi-stage gradient micropore injection structure realizes the synergistic effect of "surface atomization cooling-middle layer jet cooling-deep layer wall cooling", so that cooling medium is evenly covered in processing area, avoid local overheating or insufficient cooling, deflection spiral hole channel enhances the turbulent effect of cooling medium, improve heat exchange efficiency;Hexagonal dense-row spoiler hole strengthens jet impact, penetrates pool steam barrier;Hourglass-shaped contraction-dilation hole forms cryogenic gas film, protects workpiece surface.

Description

Technical Field

[0001] This utility model relates to the field of additive and subtractive manufacturing technology, specifically to a cooling device for the metal additive and subtractive composite manufacturing process. Background Technology

[0002] In modern manufacturing, metal additive and subtractive manufacturing technology has been widely applied in key fields such as aerospace, high-end equipment, and mold manufacturing due to its advantages of enabling integrated molding of complex structural parts and balancing material utilization and processing accuracy. The core feature of this technology is that additive manufacturing processes (such as cladding and sintering) using high-power heat sources (such as laser beams, electron beams, or electric arcs) are performed alternately with mechanical cutting processes (such as milling and turning), which simultaneously builds the prototype of the workpiece and completes precision forming processing.

[0003] However, this alternating heating-cutting machining mode keeps the workpiece constantly in a rapid and intense heating-cooling cycle, posing significant thermal management challenges to the manufacturing process. Current traditional cooling methods in the industry generally suffer from the following key technical deficiencies: 1. Traditional cooling devices often employ single-channel injection or fixed-channel heat dissipation designs. The flow path of the cooling medium in the processing area is limited by the structural design, which can easily lead to local accumulation or dead zones in the flow. This results in significant differences in cooling efficiency between the workpiece surface and interior. Some areas become overcooled due to excessive cooling medium, while some high-temperature areas remain overheated due to insufficient cooling medium supply. This directly affects the dimensional accuracy, surface quality, and forming consistency of the workpiece, thereby reducing production efficiency.

[0004] 2. Traditional heat dissipation structures (such as straight finned heat sinks and single-channel cooling pipes) have a single heat exchange path and do not fully consider the optimization of the flow pattern of the cooling medium, resulting in heat not being able to be quickly and efficiently removed from the processing area. Especially in scenarios where high-power heat sources are continuously operating, the heat dissipation rate is much lower than the heat generation rate, and a large amount of heat accumulates inside the workpiece and the cooling device itself, which not only exacerbates the problem of uneven cooling but may also shorten the service life of the cooling device.

[0005] 3. Due to the significant thermal expansion and contraction effect of materials during rapid heating and cooling, traditional cooling methods cannot adjust the cooling intensity according to the real-time heat distribution of the workpiece. This leads to excessive concentration of thermal stress inside the workpiece, especially in complex geometries (such as thin walls, hollowed-out surfaces, and irregular curved surfaces) and at interfaces between different materials. This concentrated thermal stress easily causes microcracks, deformation, or even cracking in the workpiece, severely damaging the mechanical properties of the material (such as strength, toughness, and fatigue life), resulting in a significant decrease in yield and making it difficult to meet the stringent reliability requirements of high-end equipment for structural components. Utility Model Content

[0006] The purpose of this invention is to provide a cooling device for the metal additive and subtractive composite manufacturing process, so as to solve the problems of uneven cooling, low heat dissipation efficiency and thermal stress concentration in traditional cooling methods, achieve uniform temperature control in the processing area, and ensure processing quality.

[0007] To achieve the above objectives, this application proposes a cooling device for a metal additive-subtractive composite manufacturing process, comprising a cooling device body, wherein a nozzle module is provided at the top of the cooling device body. A deformation cavity is installed inside the end, and a heat dissipation unit is provided between the nozzle module and the deformation cavity; The nozzle module is divided into three layers from the outside to the inside: the outermost layer is a truncated cone diffuser ring, the middle layer is a cylindrical ring, and the inner layer is a constriction throat ring.

[0008] In one embodiment, the truncated cone diffusion ring has a plurality of first channels, which are arranged radially and spirally on the truncated cone diffusion ring.

[0009] In one embodiment, the axis of the first channel is deflected at 14-18° from the surface normal of the truncated conical diffusion ring.

[0010] In one embodiment, the cylindrical ring belt has a plurality of second channels, the second channels being hexagonal, and micro-turbulence ribs are provided inside the second channels.

[0011] In one embodiment, the inlet section of the constricting throat ring has a double-circular transition, the outlet section has a diffusion angle, and the constricting throat ring is hourglass-shaped.

[0012] In one embodiment, the outer wall of the heat dissipation unit is provided with wave-shaped biomimetic fins, and a spiral cooling channel is installed inside the heat dissipation unit.

[0013] In one embodiment, the spiral cooling channel is spiraled upward in the form of a DNA double helix, and the two channels of the spiral cooling channel share the same physical tube wall.

[0014] In one embodiment, a flat flange is provided at the end of the deformation cavity, and a plurality of SMA hexagonal grids are distributed on the inner wall of the deformation cavity. The SMA hexagonal grids can achieve local protrusion adjustment in the range of 0-1.5mm under current excitation.

[0015] In one embodiment, the surface of the SMA hexagonal mesh is coated with a ceramic-based thermal protection layer, the thickness of which is 0.2-0.5 mm.

[0016] In one embodiment, a piezoelectric ceramic sensor array is uniformly arranged inside the deformation cavity.

[0017] The advantages of the above technical solution adopted in this utility model compared with the prior art are: 1. The multi-level gradient micro-orifice jet structure achieves the synergistic effect of "surface atomization cooling - middle layer jet cooling - deep wall-attached cooling", so that the cooling medium is evenly covered in the processing area, avoiding local overheating or insufficient cooling. The 14-18° deflected spiral channel enhances the turbulence effect of the cooling medium and improves heat exchange efficiency; the hexagonal densely packed turbulence holes strengthen the jet impact and penetrate the steam barrier of the molten pool; the hourglass-shaped contraction-expansion holes form a low-temperature gas film to protect the workpiece surface.

[0018] 2. The SMA hexagonal mesh deformation cavity can adjust the local protrusion height in real time according to the heat distribution of the workpiece, automatically match the shape of the cooling channel, eliminate the "cooling dead zone" of the traditional fixed channel, and ensure the best cooling effect under rapid changing working conditions such as laser cladding and milling.

[0019] 3. The wave-shaped biomimetic fins on the outer wall of the heat dissipation unit enhance convective heat transfer by optimizing the flow pattern of the cooling medium, and its heat dissipation efficiency is significantly improved compared with the traditional straight fin structure. At the same time, the spiral cooling channel inside the heat dissipation unit not only optimizes the flow path of the cooling medium, but also effectively reduces the pressure loss during the fluid transport process. Attached Figure Description

[0020] Figure 1 A schematic diagram of the overall structure of a cooling device for a metal additive-subtractive composite manufacturing process provided by this utility model; Figure 2 A schematic diagram of the internal spiral channel structure of a cooling device for a metal additive-subtractive composite manufacturing process provided by this utility model; Figure 3 A schematic diagram of the deformation cavity structure of a cooling device for a metal additive-subtractive composite manufacturing process provided by this utility model; Figure 4 A schematic diagram of the shrinkage throat ring structure of a cooling device for a metal additive-subtractive composite manufacturing process provided by this utility model.

[0021] Legend: 1. Cooling device body; 101. Nozzle module; 102. Heat dissipation unit; 103. Deformation cavity; 104. Frustoconical diffuser ring; 105. Cylindrical ring; 106. Constriction throat ring; 107. First channel; 108. Second channel; 109. Bionic fins; 110. Spiral cooling channel; 111. SMA hexagonal grid. Detailed Implementation

[0022] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0023] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0024] In the description of this application, it should be understood that the terms "center", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0025] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0026] Example 1: like Figure 1-4 As shown, this embodiment provides a cooling device for a metal additive-subtractive composite manufacturing process, including a cooling device body 1, and a nozzle module 101, a heat dissipation unit 102, and a deformation cavity 103 integrated on the body. This cooling device is fixedly connected to the machining spindle or motion platform of the additive-subtractive composite manufacturing equipment via a flat flange at the end of the deformation cavity 103. It is installed on the side of the machining head or integrated into a multi-head system, so that the spray direction of the nozzle module 101 is aligned with the workpiece machining area. In the additive manufacturing stage (such as laser cladding), the cooling device performs multi-stage gradient cooling on the molten pool area; in the subtractive manufacturing stage (such as milling), the cooling device performs jet impact cooling on the cutting area. The deformation cavity 103 adjusts the cooling flow channel in real time according to feedback from a piezoelectric sensor to adapt to the thermal management requirements of different processing stages. The components are arranged sequentially along the axial direction of the cooling device body 1, and the specific connection relationship is as follows: The nozzle module 101 is located at the top of the cooling device body 1 and is connected to the external cooling medium supply system. It is used to apply the cooling medium to the workpiece processing area in a multi-dimensional spray form. The heat dissipation unit 102 is located at the middle end of the main body 1 of the cooling device, and its two ends are respectively sealed and connected to the outlet of the nozzle module 101 and the inlet of the deformation cavity 103, and is used to cool down the cooling medium after absorbing the heat of the workpiece. The deformation cavity 103 is installed inside the end of the cooling device body 1 and is connected to the outlet of the heat dissipation unit 102 to realize the dynamic adjustment of the cooling flow channel.

[0027] Nozzle module 101, through its orifice gradient design and flow direction combination, constructs a synergistic cooling mode of "rapid surface cooling - mid-layer penetrating cooling - deep-layer slow-release cooling": surface cooling covers the entire workpiece processing area, achieving rapid temperature reduction; mid-layer cooling penetrates to the surrounding area of ​​the molten pool, enhancing heat exchange; and deep cooling adheres to the workpiece surface, preventing localized overheating. Compared to traditional uniform orifice structure cooling devices, this nozzle module can reduce the thermal stress on the workpiece, effectively reducing the risk of workpiece deformation and cracking.

[0028] The heat dissipation unit 102 adopts a composite heat dissipation structure of "wave-shaped fins + spiral tube network": the wave-shaped fins can change the flow pattern of the cooling medium, increase the turbulence intensity, and improve the surface convection heat transfer efficiency; the spiral tube network extends the flow path of the cooling medium and at the same time realizes rapid lateral diffusion of heat, avoiding heat accumulation in local areas. Compared with the traditional straight fin structure, the heat dissipation area of ​​this heat dissipation unit is significantly increased, and the cooling rate of the cooling medium is significantly improved, which can meet the heat dissipation requirements of high-power heat sources operating continuously in metal additive and subtractive manufacturing.

[0029] The deformation cavity 103 can dynamically adjust the shape of the internal cooling channel according to the real-time heat distribution of the workpiece, so that the cooling medium is precisely matched to the high-temperature area: when the temperature of a certain area of ​​the workpiece is too high, the deformation cavity adjusts the channel to increase the supply of cooling medium to that area; when the temperature returns to normal, the channel returns to its initial state. This can eliminate the "cooling dead zone" caused by traditional fixed channels and ensure uniform temperature throughout the workpiece processing area.

[0030] Example 2: like Figure 1-4 As shown, this embodiment provides a detailed explanation of the structural details of each core component of the cooling device and elucidates its working process to ensure that the device can be stably assembled and operated.

[0031] Nozzle module 101 is truncated conical in shape and consists of three independent channel layers from the outside to the inside. Each layer is isolated by a sealing structure to prevent cross-flow of the cooling medium. Outermost layer: truncated cone diffuser ring 104, with several first channels 107 on the ring body. The first channels 107 are arranged in a radial spiral. The axis of the channels is deflected at 14-18° from the normal of the surface of the truncated cone diffuser ring 104, similar to the structure of an "inclined shower head", which can form a large-area atomized cooling curtain. Middle layer: Cylindrical ring 105, with several hexagonal second channels 108 on the ring body. Micro-turbulence ribs are set in the second channels 108 (to enhance medium turbulence). The channel arrangement is similar to "diesel injector orifice array". The center distance between adjacent second channels 108 can be equal to 1.5 times the orifice diameter to ensure that the jet coverage is seamless. Inner layer: 106 constriction throat ring, double arc transition at the inlet section (to avoid sudden changes in the flow resistance of the cooling medium), and 20° diffusion angle at the outlet section. The whole structure is hourglass-shaped and can form a low-temperature gas film that adheres to the surface of the workpiece. The nozzle module 101 has a tapering step from the outer layer to the middle layer and a vortex guide groove from the middle layer to the inner layer to guide the orderly flow of the cooling medium; each layer is provided with a nano sealing ring groove and built-in seal to ensure that the cooling medium is leak-free.

[0032] The heat dissipation unit 102 is cylindrical in shape, and its core structure includes: Outer wall: It is equipped with wave-shaped biomimetic fins 109. The shape of the fins simulates the heat dissipation structure of natural organisms, which can efficiently guide the flow of air and cooling medium. Internally: A spiral cooling channel 110 is installed, which spirals upward in the form of a DNA double helix. The two channels share the same physical tube wall (reducing structural volume and improving space utilization). At the same time, the copper alloy inner wall of the heat dissipation unit 102 is provided with staggered microridges, which can generate a swirling effect, further optimizing the flow path of the cooling medium and enhancing heat exchange efficiency.

[0033] The deformation cavity 103 is generally inverted conical in shape, with a flat flange at the end (for positioning and connection with external equipment). Its core structure includes: Inner wall: SMA hexagonal mesh 111 is laid. SMA (shape memory alloy) material has the ability to deform under temperature or current excitation, which can drive the mesh to bulge or reset locally, thereby changing the shape of the cooling channel. The inner side of the deformation cavity 103 is uniformly arranged with a piezoelectric ceramic sensor array for real-time monitoring of the temperature distribution on the workpiece surface. Each grid cell of the SMA hexagonal mesh 111 corresponds to the signal acquisition area of ​​the piezoelectric ceramic sensor array and is connected to a microprocessor. According to the temperature data fed back by the sensor array, the microprocessor applies a pulse current to the SMA grid cell corresponding to the local high temperature area, heating it to the phase transition temperature through the Joule effect, thereby generating a predetermined bulge deformation in the range of 0-1.5mm to adjust the shape of the cooling channel in that area. The surface of the SMA hexagonal mesh 111 is coated with a thermal protection layer to prevent molten metal adhesion and high temperature damage. An array of piezoelectric ceramic sensors is arranged inside the deformation cavity 103 to collect workpiece thermal distribution data in real time and transmit the data to an external microprocessor to provide a basis for flow channel adjustment.

[0034] The working process of the above-mentioned device is as follows: During the cooling medium injection stage, the external cooling medium (such as water or inert gas) is pressurized and enters the nozzle module 101 from the top of the main body 1 of the cooling device, passing through a three-layer channel structure in sequence: The first channel 107 of the truncated cone diffusion ring 104 (which is a deflection spiral hole) forms an atomized cooling curtain, covering a large area of ​​the workpiece and achieving rapid surface cooling. The second channel 108 (hexagonal with micro-turbulence rib) of the cylindrical ring belt 105 generates a high-speed jet that penetrates the steam barrier generated by the molten pool in the metal additive manufacturing process and reaches the high-temperature core area, thereby enhancing the heat exchange in the middle layer. The hourglass-shaped channels of the constriction throat ring 106 form a low-temperature adhering gas film that adheres to the workpiece surface, suppresses deep local overheating, and protects the workpiece surface processing quality.

[0035] After absorbing heat from the workpiece during the cooling medium heat dissipation stage, the cooling medium enters the heat dissipation unit 102. The wave-shaped biomimetic fins 109 enhance the convective heat exchange between the cooling medium and the outside environment, quickly releasing some of the heat; The cooling medium flows into the helical cooling channel 110 in the form of a DNA double helix. The staggered microridges on the inner wall of the channel generate a swirling effect, prolonging the heat exchange time and accelerating the lateral diffusion of heat. Flow channel adaptive adjustment stage: The piezoelectric ceramic sensor array set inside or around the deformation cavity 103 collects the workpiece heat distribution data in real time and transmits the data to an external microprocessor; The microprocessor generates control commands based on the heat distribution data and drives the deformation cavity 103 to produce corresponding local deformation. In a preferred embodiment, the command is a current signal output to the SMA hexagonal grid 111. This causes a local protrusion in the flow channel wall of the corresponding high-temperature area of ​​the workpiece to occur in the range of 0 to 1.5 mm, thereby adaptively changing the cooling flow channel shape and increasing the supply of cooling medium in the high-temperature area. When the workpiece temperature distribution returns to uniformity, the control command is adjusted and the flow channel shape is reset, thereby achieving dynamic and uniform temperature control of the entire processing area.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application 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 of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A cooling device for a metal additive-subtractive composite manufacturing process, comprising a cooling device body (1), characterized in that: The top of the cooling device body (1) is provided with a nozzle module (101). A deformation cavity (103) is installed inside the end, and a heat dissipation unit (102) is provided between the nozzle module (101) and the deformation cavity (103). The nozzle module (101) is divided into three layers from the outside to the inside. The outermost layer is a truncated cone diffusion ring (104), the middle layer of the nozzle module (101) is a cylindrical ring (105), and the inner layer of the nozzle module (101) is a constriction throat ring (106).

2. The cooling device for a metal additive-subtractive composite manufacturing process according to claim 1, characterized in that: The truncated cone diffusion ring (104) has a plurality of first channels (107) arranged in a radial spiral on the truncated cone diffusion ring (104).

3. A cooling device for a metal additive-subtractive composite manufacturing process according to claim 2, characterized in that: The axis of the first channel (107) is deflected by 14-18° from the surface normal of the truncated cone diffusion ring (104).

4. A cooling device for a metal additive-subtractive composite manufacturing process according to claim 1, characterized in that: The cylindrical ring (105) has several second channels (108), each of which is hexagonal and contains micro-turbulence ribs.

5. A cooling device for a metal additive-subtractive composite manufacturing process according to claim 1, characterized in that: The constricting throat ring (106) has a double-circular arc transition at the entrance and a diffusion angle at the exit, and the constricting throat ring (106) is hourglass-shaped.

6. A cooling device for a metal additive-subtractive composite manufacturing process according to claim 1, characterized in that: The outer wall of the heat dissipation unit (102) is provided with wave-shaped bionic fins (109), and a spiral cooling channel (110) is installed inside the heat dissipation unit (102).

7. A cooling device for a metal additive-subtractive composite manufacturing process according to claim 6, characterized in that: The spiral cooling channel (110) is spiraled upward in the form of a DNA double helix, and the two channels of the spiral cooling channel (110) share the same physical tube wall.

8. A cooling device for a metal additive-subtractive composite manufacturing process according to claim 1, characterized in that: The deformation cavity (103) is provided with a flat flange at its end. Several SMA hexagonal grids (111) are distributed on the inner wall of the deformation cavity (103). The SMA hexagonal grids (111) can achieve local protrusion adjustment in the range of 0-1.5mm under current excitation.

9. A cooling device for a metal additive-subtractive composite manufacturing process according to claim 8, characterized in that: The surface of the SMA hexagonal mesh (111) is coated with a ceramic-based thermal protection layer with a thickness of 0.2-0.5 mm.

10. A cooling device for a metal additive-subtractive composite manufacturing process according to claim 8, characterized in that: The deformation cavity (103) has a uniformly arranged piezoelectric ceramic sensor array on its inner side.

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