Micro-channel radiator with micro-texture surface and preparation method of micro-channel radiator

Abstract

The invention provides a micro-channel radiator with a micro-texture surface and a preparation method of the micro-channel radiator, and relates to the technical field of heat dissipation of high-heat-flux electronic devices. Comprising a liquid flowing cavity and an upper cover plate attached to the liquid flowing cavity, and a liquid inlet and a liquid outlet are formed in the two sides of the upper cover plate or the liquid flowing cavity; the micro-channel radiator further comprises a micro-channel base body placed in the liquid flowing cavity, a plurality of micro-channels which are arranged in parallel at intervals in an array mode are formed in the micro-channel base body, and periodic microtextures are arranged on the wall faces of the micro-channels so as to regulate and control the heat dissipation performance of the micro-channel radiator. According to the scheme, the ultra-large depth-to-width ratio micro-channel radiator with the micro-texture surface is prepared.

Description

Technical Field

[0001] The present invention relates to the technical field of heat dissipation of electronic devices with high heat flux density, and in particular to a microchannel heat sink with an ultra-large aspect ratio and a preparation method thereof. Background Art

[0002] Microchannel heat sink is a new type of heat sink that quickly removes heat from electronic devices by contacting the flowing liquid working medium with the microchannel wall. It has the advantages of small size and large heat dissipation specific surface area, and is an ideal component to solve the heat dissipation problem of high heat flux density electronic devices. Studies have shown that ultra-large aspect ratio microchannel heat sinks with an aspect ratio greater than 15 show excellent heat dissipation performance, and their critical heat flux can exceed 1000W / cm 2 . Processing micro-textures on the microchannel surface and regulating the heat transfer area, wetting performance, bubble nucleation density, etc. can further improve the heat dissipation performance of the microchannel heat sink. However, the ultra-large aspect ratio microchannel heat sink is a typical narrow gap, thin wall, weak rigidity and difficult to process structure. It is difficult to achieve deformation-free and heat-free processing of its geometric structure and to process micro-textures on the surface of the ultra-large aspect ratio microchannel.

[0003] Deep reactive ion etching technology, electrochemical deposition, additive manufacturing and other methods can all process ultra-large aspect ratio microchannel heat sinks, but they all have bottleneck problems such as low processing efficiency and high cost. Wire cutting of electrical discharge can also achieve the processing of ultra-large aspect ratio microchannel heat sinks, but this method is single-wire cutting, low efficiency, and there is thermal damage and large surface thermal resistance on the processed surface. The above processing methods cannot form surface microtexture while processing ultra-large aspect ratio microchannels, and require additional post-processing steps.

[0004] Japanese patent JP2005032749A discloses a heat sink manufacturing method and manufacturing device, which uses an abrasive wire saw to cut and process slit heat sinks of different shapes. U.S. Patent US6390181B1 discloses a dense fin tungsten carbide and polycrystalline diamond cooling module, pointing out that dense fin tungsten carbide heat sinks can be processed using a wire saw, and further mentions that the rough surface after wire saw processing can increase the contact area, thereby improving the heat dissipation effect. Abrasive wire saw processing of ultra-large aspect ratio microchannel heat sinks has significant advantages in improving processing efficiency, but the existing technology mainly stays in the conventional sense of surface roughening through wire saws, and fails to fully recognize the important influence of surface wettability on heat dissipation effect. In addition, different usage scenarios have different requirements for the heat dissipation performance of microchannel heat sinks. However, the existing technology fails to accurately design and regulate the micro-texture of the wire saw processed surface according to specific application scenarios, resulting in large differences in performance of existing microchannel heat sinks in diverse application environments, and cannot fully exert its heat dissipation potential. Due to the lack of precise design of surface microstructure, the performance of microchannel heat sinks processed by abrasive wire saws is significantly dispersed, which makes it difficult to ensure product consistency and stability in actual production and application, and increases the difficulty and cost of quality control. Therefore, when using abrasive wire saws to process ultra-large aspect ratio microchannel heat sinks, how to achieve precise construction and controllable processing of wire saw surface microtexture has become a key issue that needs to be solved urgently. Summary of the invention

[0005] The present invention discloses a microchannel heat sink with a micro-textured surface, aiming to improve the above-mentioned problems.

[0006] The present invention adopts the following scheme: A microchannel heat sink with a microtextured surface comprises a liquid flow cavity and an upper cover plate attached to the liquid flow cavity; a liquid inlet and an outlet are arranged on both sides of the upper cover plate or the liquid flow cavity; and a microchannel substrate is placed in the liquid flow cavity; a plurality of microchannels arranged in a parallel spaced array are formed on the microchannel substrate; the wall of the microchannel is arranged with a periodic microtexture; the structural parameters of the periodic microtexture can be accurately designed and processed according to the requirements of the application; when the application is liquid single-phase forced convection heat transfer, the surface periodic microtexture is designed to be a hydrophilic structure that conforms to the Wenzel model to increase the ratio of the wetted area of ​​the fluid to the solid, thereby increasing the heat dissipation area of ​​the microchannel; when the application is liquid two-phase flow boiling heat transfer, the surface periodic microtexture is designed to be a hydrophobic structure that conforms to the Cassie-Baxter model to reduce flow resistance, promote bubble generation and detachment, and enhance the boiling heat transfer coefficient; Furthermore, the surface profile of the periodic micro-texture is a triangular wave.

[0007] Furthermore, the microchannel is provided with a microstructure of one or a combination of rectangular, circular, trapezoidal, and wavy shapes on a cross section perpendicular to the fluid direction.

[0008] Furthermore, the microstructures of each group of microchannels are arranged in a plurality along the height direction of the microchannel substrate.

[0009] Furthermore, the microchannel substrate includes a plurality of microcolumns arranged in a parallel and spaced array, the microchannel is formed between adjacent microcolumns, and the cross-section of the microcolumns in a direction parallel to the bottom surface of the microchannel substrate is a rhombus.

[0010] Furthermore, the ratio of the depth to the width of the microchannel is the aspect ratio, and the aspect ratio is greater than 15.

[0011] The present invention also provides a method for preparing the microchannel heat sink with a micro-textured surface, which specifically comprises the following steps: S1: Design the geometric structure and surface microtexture parameters of the microchannel according to the application, select the type of fixed abrasive wire saw and dry and wet processing methods according to the microchannel substrate material, select the specifications of the abrasive wire saw and wire roller according to the microchannel structural parameters, and design the processing trajectory according to the microchannel structure; S2: Mounting the workpiece on a workbench of a consolidated abrasive wire saw multi-wire cutting machine; S3: Import the machining trajectory parameters of the workpiece into the bonded abrasive wire saw cutting machine, and set the wire tension and wire speed v s , workpiece feed speed v f and wire saw reciprocating cycle T r :According to the material properties of the workpiece, find the relationship between the microstructure peak-to-valley value PV, wavelength λ and processing parameters: PV= k 1 · v f a · v s b · T r c , λ = k 2 · v f m · v s n · T r f ;in, k 1 ,a , b , c is an empirical parameter related to the material. k 2 , m , f is approximately equal to 1, n Approximately equal to 0, the processing parameters are inversely calculated; S4: operate the control panel to lower the bottom surface of the workpiece to a position where it will contact the fixed abrasive wire saw wire mesh; S5: Run the machining program: the fixed abrasive wire saw mesh performs periodic reciprocating motion under the drive system of the machine tool, the workpiece starts to be fed, the wire saw mesh contacts the workpiece and starts to remove the material, and during the reciprocating motion of the wire saw mesh, the wire saw forms a regular microstructure through lateral motion; S6: After the processing program is completed, the workpiece is taken out, cleaned, and dried to obtain the final microchannel matrix; S7: Encapsulating the microchannel substrate, the upper cover plate, and the liquid flow cavity to obtain a final microchannel heat sink with an ultra-large aspect ratio and a micro-textured surface.

[0012] Furthermore, when the microchannel substrate is a non-metallic material with relatively high hardness, the abrasive wire saw in step S1 is an active abrasive wire saw, the wet and dry processing method is dry processing, and the active abrasive can catalyze the phase change of the substrate material under the action of pressure and temperature, thereby reducing the processing difficulty.

[0013] Further, when a plurality of micro-pillars arranged in a parallel spaced array are processed on the micro-channel substrate, and the cross-section of the micro-pillars in a direction parallel to the bottom surface of the micro-channel substrate is a rhombus, in step S5, the processing is divided into two angles of vertical feed cutting, l 1 and l 2 Distinguish between step ① and step ②: first install the microchannel substrate above the center of the wire saw wire mesh, and the front side is parallel to the side of the wire roller; then the workbench is rotated by an angle of σ to start l 1 When the preset processing depth is reached, the wire saw wire mesh stops moving and the workbench rises back to the coordinate origin, completing the processing of step ①; then the workbench proceeds to l 1 The angle θ is used as the reference to start the rotation. l 2 Corresponding processing; when the preset processing depth is reached, the processing of step ② is completed, and finally the processing of the diamond column array microchannel structure is realized.

[0014] Beneficial effects: The present invention provides an ultra-large aspect ratio microchannel heat sink with a micro-textured surface. The structural parameters of the surface micro-texture can be precisely designed and processed according to the requirements of the application. The heat dissipation performance of the microchannel can be regulated by setting the periodic micro-texture of the microchannel wall. When the ultra-large aspect ratio microchannel heat sink is applied for liquid single-phase forced convection heat transfer, the surface periodic micro-texture is designed to be a hydrophilic structure that conforms to the Wenzel model, which can increase the ratio of the wetting area of ​​the fluid to the solid, thereby increasing the heat dissipation area of ​​the microchannel. When the ultra-large aspect ratio microchannel heat sink is applied for liquid two-phase flow boiling heat transfer, the surface periodic micro-texture can be designed to be a hydrophobic structure that conforms to the Cassie-Baxter model to reduce flow resistance, promote bubble generation and detachment, and enhance the boiling heat transfer coefficient. The preparation method of one-step forming by reciprocating multi-wire cutting with a consolidated abrasive wire saw can realize one-step forming processing of microchannel ultra-large aspect ratio structure and surface microtexture, and the surface microstructure processing does not require additional post-processing steps; the diameter of the cutting tool consolidated abrasive wire saw can be as small as less than 50 microns, which is flexible processing, easy to realize ultra-large aspect ratio narrow slit structure processing and thin-walled structure is not easy to deform; the cutting processing temperature of the consolidated abrasive wire saw is low, there is no thermal damage during processing, and the microchannel wall surface will not be deteriorated to reduce the thermal conductivity of the material; this method can process metals and non-metals, and the material application range is wide; all ultra-large aspect ratio microchannels in the same direction can be batch processed in a single pass, the process is simple, the equipment requirements are low, the cost is low, the processing efficiency is high, and it is easy to mass produce on a large scale; there is no waste liquid pollution problem in the processing process, it is green and environmentally friendly, and the energy consumption is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of the structure of a microchannel heat sink with a micro-textured surface having a large aspect ratio in Example 1; Figure 2 Schematic diagram of the structure of a microchannel substrate with an ultra-large aspect ratio and a micro-textured surface in Example 1; Figure 3 A schematic cross-sectional view of a microchannel substrate structure with an ultra-large aspect ratio and a micro-textured surface according to Example 1; Figure 4 Schematic diagram of the multi-wire cutting process of the diamond wire saw for the ultra-large aspect ratio microchannel structure with micro-textured surface in Examples 1 to 7. v fy , v fz is the feed speed in different axes, v s Indicates line speed; Figure 5 The microchannel substrate actually processed by diamond wire saw multi-wire cutting in Example 2; Figure 6The 3D morphology and 2D contour diagram of the microstructure of the microchannel substrate channel wall line marks actually processed in Example 2; Figure 7 Schematic diagram of the ultra-large aspect ratio microchannel structure with a micro-textured surface in Example 3; Figure 8 Schematic diagram of the cross section of the ultra-large aspect ratio microchannel structure with a micro-textured surface in Example 3; Fig. 9 Schematic diagram of the processing trajectory of the ultra-large aspect ratio microchannel structure with a micro-textured surface in Example 3; Fig.10 Schematic diagram of the ultra-large aspect ratio microchannel structure with a micro-textured surface in Example 4; Fig.11 Schematic diagram of the cross section of the ultra-large aspect ratio microchannel structure with a micro-textured surface in Example 4; Fig.12 Schematic diagram of the processing trajectory of the ultra-large aspect ratio microchannel structure with a micro-textured surface in Example 4; Fig.13 Schematic diagram of an ultra-large aspect ratio microchannel structure with a micro-textured surface in Example 5; Fig.14 Schematic diagram of the cross section of the ultra-large aspect ratio microchannel structure with a micro-textured surface in Example 5; Fig.15 Schematic diagram of the processing trajectory of the ultra-large aspect ratio microchannel structure with a micro-textured surface in Example 5; Fig.16 Schematic diagram of an ultra-large aspect ratio microchannel structure with a micro-textured surface in Example 6; Fig.17 Schematic diagram of the cross section of the ultra-large aspect ratio microchannel structure with a micro-textured surface in Example 6; Fig.18 Schematic diagram of the processing trajectory of the ultra-large aspect ratio microchannel structure with a micro-textured surface in Example 6; Fig.19 Schematic diagram of an ultra-large aspect ratio microchannel structure with a micro-textured surface in Example 7; Fig. 20 Schematic diagram of the cross section of the ultra-large aspect ratio microchannel structure with a micro-textured surface in Example 7; Fig.21 Schematic diagram of the processing trajectory of the ultra-large aspect ratio microchannel structure with a micro-textured surface in Example 7; Fig. 22 Schematic diagram of a coated hard abrasive wire saw wrapped with active pure metal used in multi-wire cutting in Example 8; Figure numerals: upper cover plate 1, coolant inlet 2, coolant outlet 3, ultra-large aspect ratio microchannel substrate 4, liquid flow chamber 5, workpiece 6, wire roller 7, diamond wire saw wire mesh 8, fixed plate 9, workbench 10, hard abrasive grains 11, metal coating 12, coated hard abrasive grains 13 core wire 14, metal binder 15. DETAILED DESCRIPTION

[0016] Example 1 like Figure 1 and Figure 2 As shown, this embodiment provides a microchannel heat sink with an ultra-large aspect ratio and a micro-textured surface, which includes an upper cover plate 1, a cooling liquid inlet 2, a cooling liquid outlet 3, a microchannel substrate 4 with an ultra-large aspect ratio, and a liquid flow cavity 5. The microchannel substrate 4 is formed with a plurality of microchannels arranged in a parallel spaced array, and the wall of the microchannel is arranged with microstructures to regulate the heat dissipation performance of the microchannel; the cooling liquid of the microchannel heat sink enters the liquid flow cavity 5 at a certain flow rate through the cooling liquid inlet 2 on the upper cover plate 1, flows through the microchannel substrate 4, and then flows out from the cooling liquid outlet 3.

[0017] In this embodiment, microchannels arranged in parallel and spaced apart are provided on the microchannel substrate 4, and the microchannels are suitable for the passage of coolant fluid. The wall of the microchannel is arranged with periodic microtextures; the surface profile of the periodic microtextures is a triangular wave; the structural parameters of the periodic microtextures can be precisely designed and processed according to the requirements of the application; when the application is liquid single-phase forced convection heat transfer, the surface periodic microtexture is designed to be a hydrophilic structure that conforms to the Wenzel model to increase the ratio of the wetted area of ​​the fluid to the solid, thereby increasing the heat dissipation area of ​​the microchannel; when the application is liquid two-phase flow boiling heat transfer, the surface periodic microtexture is designed to be a hydrophobic structure that conforms to the Cassie-Baxter model to reduce flow resistance, promote bubble generation and detachment, and enhance the boiling heat transfer coefficient; on the cross section of the microchannel perpendicular to the fluid direction, a combination of one or more microstructures of rectangular, circular, trapezoidal, and wavy shapes is provided, and the microstructures of each group of the microchannels are provided along the height direction of the microchannel substrate. By setting the microstructure, the fluid turbulence effect can be enhanced, the flow resistance can be reduced, the heat exchange area can be increased, the boundary layer can be destroyed, the critical heat flux density can be increased, and the heat dissipation performance of the microchannel can be improved. Here, the ratio of the depth to the width of the microchannel is the aspect ratio, and the aspect ratio is greater than 15.

[0018] In this embodiment, the hydrophilic structure of the Wenzel model refers to a structure in which the liquid can completely fill the micro-textured surface, and the hydrophobic structure of the Cassie-Baxter model refers to a structure in which the liquid and the gas co-occupy the micro-textured surface (composite interface). The formulas of the two models are prior art and will not be repeated here.

[0019] Preferably, a plurality of micro-pillars arranged in parallel and spaced arrays are formed on the micro-channel substrate 4, the micro-channel is formed between adjacent micro-pillars, and the cross-section of the micro-pillars in the direction parallel to the bottom surface of the micro-channel substrate is a rhombus. The micro-pillars can optimize the fluid flow characteristics and heat transfer characteristics.

[0020] Example 2 Microchannel heat sink substrate structure Figure 2 and Figure 3 As shown, the microchannel matrix material is copper block, taking the specific dimensions L=D=30mm, H=10mm as an example; the microchannel structure dimensions are set to h=8000μm, a=270μm, b=750μm, the microchannel depth-to-width ratio is 29.6, and the application occasion of the microchannel radiator is liquid two-phase flow boiling heat transfer. The surface microtexture is designed to be a hydrophobic structure, and the surface microtexture dimensions are PV=4μm, λ=0.21mm.

[0021] Combination Figure 4 The one-step forming preparation method of the above-mentioned ultra-large aspect ratio microchannel heat sink with a micro-textured surface comprises the following steps: S1: According to the structure of the microchannel substrate 4, an electroplated diamond wire saw with a wire diameter of 250 μm and a wire roller 7 with a wire groove spacing of 750 μm are selected to form a diamond wire saw wire mesh 8, and the corresponding processing trajectory is a straight line in the Z-axis direction; S2: Using AB glue as an adhesive to bond the workpiece 6 to the fixing plate 9, and fastening the fixing plate 9 to the worktable 10 through the grooves of the fixing plate 9 and the worktable 10, so that the workpiece 6 is installed on the worktable 10 of the diamond wire saw multi-wire cutting machine tool; in this embodiment, the workpiece 6 refers to the microchannel substrate to be processed; S3: Import the machining trajectory parameters of workpiece 6 on the control panel of the diamond wire saw multi-wire cutting machine tool and set the process parameters: the wire tension is 40N; the Z-axis feed trajectory adopts the linear speed v s =25m / s, workpiece feed speed v fz =0.15mm / min and wire saw reciprocating cycle T r =85s; Linear velocity at the bottom of the microchannel v s =25m / s, workpiece feed speed v fz =0.0001mm / min, reciprocating cycle of wire saw T r =100s, so that the workpiece is kept in a state of almost no feeding for 10 minutes, eliminating the feed lag caused by the wire bow, thereby achieving the theoretically designed feed distance and ensuring the processing accuracy; S4: operate the control panel to lower the bottom surface of the workpiece 6 to a position where it will contact the diamond wire saw wire mesh 8, and reset the coordinates of this position to zero as the tool coordinate starting point to complete the tool setting; S5: Run the processing program: the diamond wire saw wire net 8 is driven by the machine tool drive system to perform periodic reciprocating motion, the workpiece 6 starts to feed according to the introduced processing trajectory, the diamond wire saw wire net 8 contacts the workpiece 6 and starts to scratch and remove materials, and during the reciprocating motion of the diamond wire saw wire net, the wire saw will move sideways according to the set trajectory route to form a regular microstructure; S6: After the processing program is completed, the binder is removed to take out the workpiece 6, which is placed in an ultrasonic alcohol bath for cleaning for 5 minutes and placed in a 50°C oven for drying for 30 minutes to obtain the final ultra-large aspect ratio microchannel substrate. Figure 5 shown.

[0022] S7: The ultra-large aspect ratio microchannel substrate 4 is embedded in the liquid flow cavity 5 to fit the two together. The upper cover plate 1 is placed on top of the substrate, and the three are sealed by brazing. Water pipes are connected to the liquid inlet 2 and outlet 3 of the upper cover plate 1, and connected to a water pump to form a circulation loop for liquid convection, and finally a complete ultra-large aspect ratio microchannel radiator with a micro-textured surface is obtained.

[0023] like Figure 6 As shown; the micro texture obtained by the process parameters in this embodiment is in the shape of a triangular wave. After actual measurement by the 3D optical profiler Zygo, the average values ​​of its characteristic parameters are obtained: PV=3.84μm, λ=0.16mm.

[0024] In this embodiment, the electroplated diamond wire saw refers to a wire saw with diamond abrasive grains fixed on the cutting core wire by electroplating. Under the same structural conditions of the ultra-large aspect ratio microchannel substrate, the diamond wire saw reciprocating multi-wire cutting processing method used in this embodiment takes about 63 minutes, while the industrial electric spark wire cutting takes about 223 minutes. The efficiency of the diamond wire saw multi-wire cutting is more than 70% higher than that of the electric spark wire cutting. In the liquid two-phase flow boiling heat transfer test, the ultra-large aspect ratio microchannel radiator processed by the diamond wire saw multi-wire cutting can withstand a higher heat flux density than the sample processed by the electric spark wire cutting, so that the test wall can maintain a better temperature, and the heat dissipation performance is improved by more than 50%.

[0025] Example 3 The substrate structure of the micro-channel heat sink with a micro-textured surface and a large aspect ratio sidewall rectangular recess is as follows: Figures 7 and 8As shown, the heat sink base material is copper block, the specific dimensions of the microchannel base are L=D=10.4mm, H=6mm; the microchannel structure dimensions are h=5000μm, a=100μm, b=700μm, c 1 =c 2 =1000μm, e=f=500μm, the microchannel depth-to-width ratio is 50, the application of the microchannel radiator is liquid two-phase flow boiling heat transfer, its surface microtexture is designed to be a hydrophobic structure, the surface microtexture size PV=4μm, λ=0.21mm. Figure 4 , Figure 7 and Figure 8 The one-step forming preparation method of the ultra-large aspect ratio microchannel heat sink with a micro-textured surface comprises the following steps: S1: According to the microchannel substrate structure, an electroplated diamond wire saw with a wire diameter of 80 μm and a wire roller 7 with a wire groove spacing of 700 μm are selected to form a diamond wire saw wire mesh 8, and the corresponding processing trajectory is designed, such as Fig. 9 ; S2: Using AB glue as an adhesive to bond the workpiece to the fixing plate 9, and fastening the fixing plate 9 and the worktable 10 together through the grooves of the fixing plate 9 and the worktable 10, so that the workpiece 6 is mounted on the worktable 10 of the diamond wire saw multi-wire cutting machine tool; S3: Import the machining trajectory file of workpiece 6 on the control panel of the diamond wire saw multi-wire cutting machine and set the process parameters: the wire tension is 40N; the Z-axis feed trajectory adopts the linear speed v s =25m / s, workpiece feed speed v fz =0.15mm / min and wire saw reciprocating cycle T r =85s; linear speed is used at the corner junction of the recessed structure v s =25m / s, workpiece feed speed v fz =0.0001mm / min, reciprocating cycle of wire saw T r = 85s, so that the workpiece is kept in a state of almost no feed for 10 minutes, eliminating the feed lag caused by the wire bow, thereby achieving the theoretically designed feed distance and ensuring the processing accuracy; the Y-axis feed trajectory adopts the linear speed v s =25m / s, workpiece feed speed v fy =0.15mm / min, reciprocating cycle of wire saw T r =85s; S4: operate the control panel to lower the bottom surface of the workpiece 6 to a position where it will contact the diamond wire saw wire mesh 8, and reset the coordinates of this position to zero as the tool coordinate starting point to complete the tool setting; S5: Run the processing program: the diamond wire saw wire net 8 is driven by the machine tool drive system to perform periodic reciprocating motion, the workpiece 6 starts to feed according to the introduced processing trajectory, the diamond wire saw wire net 8 contacts the workpiece 6 and starts to scratch and remove the material, and during the reciprocating motion of the diamond wire saw wire net, the wire saw will move sideways to form a regular microstructure; S6: After the processing program is completed, the binder is removed to take out the workpiece 6, which is placed in an ultrasonic alcohol bath for cleaning for 5 minutes and placed in a 50° C. oven for drying for 30 minutes to obtain the final ultra-large aspect ratio microchannel substrate; S7: The ultra-large aspect ratio microchannel substrate 4 is embedded in the liquid flow cavity 5 to fit the two together. The upper cover plate 1 is placed on top of it, and the three are sealed by brazing. The liquid inlet 2 and outlet 3 of the upper cover plate 1 are connected to water pipes and connected to a water pump to form a circulation loop for liquid convection, and finally a complete ultra-large aspect ratio microchannel radiator with a micro-textured surface is obtained. In the liquid two-phase boiling flow heat transfer test, the ultra-large aspect ratio side wall rectangular recessed microchannel radiator processed by diamond wire saw multi-wire cutting can increase the Nusselt number by 25~35% and reduce the overall pressure drop by 8~12% compared with the non-recessed microchannel radiator.

[0026] Example 4 The substrate structure of the microchannel heat sink with a circular indented sidewall having a micro-textured surface in this embodiment is as follows: Figure 10 to Figure 11 As shown, the heat sink base material is copper block, with specific dimensions of L=D=10.4mm, H=6mm; the microchannel structure dimensions are h=5000μm, a=100μm, b=700μm, c 1 =c 2 =1000μm, d=Φ500μm, microchannel aspect ratio is 50, the application of microchannel radiator is liquid two-phase flow boiling heat transfer, its surface microtexture is designed to be a hydrophobic structure, the surface microtexture size PV=2.1μm, λ=0.25mm. The one-step forming preparation method of the ultra-large aspect ratio microchannel radiator with microtexture surface includes the following steps: S1: According to the microchannel substrate structure, an electroplated diamond wire saw with a wire diameter of 80 μm and a wire roller 7 with a wire groove spacing of 700 μm are selected to form a diamond wire saw wire mesh 8, and the corresponding processing trajectory is designed, such as Fig.12 ; S2: Using AB glue as an adhesive to bond the workpiece to the fixing plate 9, and fastening the fixing plate 9 and the worktable 10 together through the grooves of the fixing plate 9 and the worktable 10, so that the workpiece 6 is mounted on the worktable 10 of the diamond wire saw multi-wire cutting machine tool; S3: Import the machining trajectory file of workpiece 6 on the control panel of the diamond wire saw multi-wire cutting machine and set the process parameters: the wire tension is 40N; the Z-axis feed trajectory adopts the linear speed v s =15m / s, workpiece feed speed v fz =0.15mm / min, reciprocating cycle of wire saw T r =100s; linear speed is used at the corner junction of the recessed structure v s =15m / s, workpiece feed speed v fz =0.0001mm / min, reciprocating cycle of wire saw T r = 100s, so that the workpiece remains in a state of almost no feed for 10 minutes, eliminating the feed lag caused by the wire bow, thereby achieving the theoretically designed feed distance and ensuring the processing accuracy; the curve feed trajectory adopts the linear speed v s =15m / s, workpiece feed speed v fy = v fz =0.15mm / min, reciprocating cycle of wire saw T r =100s; S4: operate the control panel to lower the bottom surface of the workpiece 6 to a position where it will contact the diamond wire saw wire mesh 8, and reset the coordinates of this position to zero as the tool coordinate starting point to complete the tool setting; S5: Run the processing program: the diamond wire saw wire net 8 is driven by the machine tool drive system to perform periodic reciprocating motion, the workpiece 6 starts to feed according to the introduced processing trajectory, the diamond wire saw wire net 8 contacts the workpiece 6 and starts to scratch and remove the material, and during the reciprocating motion of the diamond wire saw wire net, the wire saw will move sideways to form a regular microstructure; S6: After the processing program is completed, the binder is removed to take out the workpiece 6, which is placed in an ultrasonic alcohol bath for cleaning for 5 minutes and placed in a 50° C. oven for drying for 30 minutes to obtain the final ultra-large aspect ratio microchannel substrate; S7: Embed the ultra-large aspect ratio microchannel substrate 4 into the liquid flow cavity 5 to fit the two. Place the upper cover plate 1 on top of it, and achieve a sealed package of the three by brazing. Connect water pipes to the liquid inlet 2 and outlet 3 of the upper cover plate 1, and connect them to a water pump to form a circulation loop for liquid convection, and finally obtain a complete ultra-large aspect ratio microchannel radiator with a micro-textured surface. In the liquid two-phase flow boiling heat transfer test, the ultra-large aspect ratio side wall circular recessed microchannel radiator processed by diamond wire saw multi-wire cutting can increase the Nusselt number by 20~30% and reduce the overall pressure drop by 5~8% compared with the non-recessed microchannel radiator.

[0027] Example 5 The substrate structure of the microchannel heat sink with a sinusoidal indentation on the sidewall with a micro-textured surface in this embodiment is as follows: Figure 13 to Figure 14 As shown, the heat sink base material is a copper block, with specific dimensions L=D=10.4mm, H=6mm; the microchannel structure dimensions are h=5000μm, a=100μm, b=700μm, c=1000μm, A=130μm, and the microchannel aspect ratio is 50. The application of the microchannel heat sink is liquid two-phase flow boiling heat transfer, and its surface microtexture is designed to be a hydrophobic structure, with a surface microtexture dimension PV=2.4μm, λ=0.15mm. The one-step forming preparation method of the ultra-large aspect ratio microchannel heat sink with a microtextured surface includes the following steps: S1: According to the microchannel substrate structure, an electroplated diamond wire saw with a wire diameter of 80 μm and a wire roller 7 with a wire groove spacing of 700 μm are selected to form a diamond wire saw wire mesh 8, and the corresponding processing trajectory is designed, such as Fig.15 ; S2: Using AB glue as an adhesive to bond the workpiece to the fixing plate 9, and fastening the fixing plate 9 and the worktable 10 together through the grooves of the fixing plate 9 and the worktable 10, so that the workpiece 6 is mounted on the worktable 10 of the diamond wire saw multi-wire cutting machine tool; S3: Import the machining trajectory file of workpiece 6 on the control panel of the diamond wire saw multi-wire cutting machine and set the process parameters: the wire tension is 40N; the curve feed trajectory adopts the linear speed v s =25m / s, workpiece feed speed v fy = v fz =0.05mm / min, reciprocating cycle of wire saw T r =180s; Linear speed is used at the corner junction of the indented structure v s =25m / s, workpiece feed speed v fz =0.0001mm / min, reciprocating cycle of wire sawT r =180s, so that the workpiece is kept in a state of almost no feeding for 10min, eliminating the feed lag caused by the wire bow, thereby achieving the theoretically designed feed distance and ensuring the processing accuracy; S4: operate the control panel to lower the bottom surface of the workpiece 6 to a position where it will contact the diamond wire saw wire mesh 8, and reset the coordinates of this position to zero as the tool coordinate starting point to complete the tool setting; S5: Run the processing program: the diamond wire saw wire net 8 is driven by the machine tool drive system to perform periodic reciprocating motion, the workpiece 6 starts to feed according to the introduced processing trajectory, the diamond wire saw wire net 8 contacts the workpiece 6 and starts to scratch and remove the material, and during the reciprocating motion of the diamond wire saw wire net, the wire saw will move sideways to form a regular microstructure; S6: After the processing program is completed, the binder is removed to take out the workpiece 6, which is placed in an ultrasonic alcohol bath for cleaning for 5 minutes and placed in a 50° C. oven for drying for 30 minutes to obtain the final ultra-large aspect ratio microchannel substrate; S7: Embed the ultra-large aspect ratio microchannel substrate 4 into the liquid flow cavity 5 to fit the two. Place the upper cover plate 1 on top of it, and achieve a sealed package of the three by brazing. Connect water pipes to the liquid inlet 2 and outlet 3 of the upper cover plate 1, and connect them to a water pump to form a circulation loop for liquid convection, and finally obtain a complete ultra-large aspect ratio microchannel radiator with a micro-textured surface. In the liquid two-phase flow boiling heat transfer test, the ultra-large aspect ratio side wall sinusoidal recessed microchannel radiator processed by diamond wire saw multi-wire cutting can increase the Nusselt number by 30~45% and reduce the overall pressure drop by 10~15% compared with the non-recessed microchannel radiator.

[0028] Example 6 The substrate structure of the circular indented microchannel heat sink with a micro-textured surface in this embodiment is as follows: Figure 16 to Figure 17 As shown, the heat sink base material is a copper block, with specific dimensions L=D=10.4mm, H=6mm; the microchannel structure dimensions are h=5000μm, a=100μm, b=700μm, d=Φ500μm, and the microchannel aspect ratio is 50. The application of the microchannel heat sink is liquid two-phase flow boiling heat transfer, and its surface microtexture is designed to be a hydrophobic structure, with a surface microtexture dimension PV=2.4μm, λ=0.8mm. The one-step forming preparation method of the ultra-large aspect ratio microchannel heat sink with a microtextured surface includes the following steps: S1: According to the microchannel substrate structure, an electroplated diamond wire saw with a wire diameter of 80 μm and a wire roller 7 with a wire groove spacing of 700 μm are selected to form a diamond wire saw wire mesh 8, and the corresponding processing trajectory is designed, such as Fig.18 ; S2: Using AB glue as an adhesive to bond the workpiece to the fixing plate 9, and fastening the fixing plate 9 and the worktable 10 together through the grooves of the fixing plate 9 and the worktable 10, so that the workpiece 6 is mounted on the worktable 10 of the diamond wire saw multi-wire cutting machine tool; S3: Import the machining trajectory file of workpiece 6 on the control panel of the diamond wire saw multi-wire cutting machine and set the process parameters: the wire tension is 40N; the Z-axis feed trajectory adopts the linear speed v s =25m / s, workpiece feed speed v fz =0.4mm / min, reciprocating cycle of wire saw T r =120s; Linear speed is used at the corner junction of the recessed structure v s =25m / s, workpiece feed speed v fz =0.0001mm / min, reciprocating cycle of wire saw T r = 100s, so that the workpiece remains in a state of almost no feed for 10 minutes, eliminating the feed lag caused by the wire bow, thereby achieving the theoretically designed feed distance and ensuring the processing accuracy; the curve feed trajectory adopts the linear speed v s =25m / s, workpiece feed speed v fy = v fz =0.03mm / min, reciprocating cycle of wire saw T r =120s; S4: operate the control panel to lower the bottom surface of the workpiece 6 to a position where it will contact the diamond wire saw wire mesh 8, and reset the coordinates of this position to zero as the tool coordinate starting point to complete the tool setting; S5: Run the processing program: the diamond wire saw wire net 8 is driven by the machine tool drive system to perform periodic reciprocating motion, the workpiece 6 starts to feed according to the introduced processing trajectory, the diamond wire saw wire net 8 contacts the workpiece 6 and starts to scratch and remove the material, and during the reciprocating motion of the diamond wire saw wire net, the wire saw will move sideways to form a regular microstructure; S6: After the processing program is completed, the binder is removed to take out the workpiece 6, which is placed in an ultrasonic alcohol bath for cleaning for 5 minutes and placed in a 50° C. oven for drying for 30 minutes to obtain the final ultra-large aspect ratio microchannel substrate; S7: The ultra-large aspect ratio microchannel substrate 4 is embedded in the liquid flow cavity 5 to fit the two together. The upper cover plate 1 is placed on top of it, and the three are sealed by brazing. The liquid inlet 2 and outlet 3 of the upper cover plate 1 are connected to water pipes and connected to a water pump to form a circulation loop for liquid convection, and finally a complete ultra-large aspect ratio microchannel radiator with a micro-textured surface is obtained. In the liquid two-phase flow boiling heat transfer test, the ultra-large aspect ratio bottom circular recessed microchannel radiator processed by diamond wire saw multi-wire cutting can increase the Nusselt number by 30~40% and reduce the overall pressure drop by 13~19% compared with the non-recessed microchannel radiator.

[0029] Example 7 The microchannel heat sink substrate structure of the ultra-large aspect ratio diamond micro-pillar array with micro-textured surface described in this embodiment is as follows: Figure 19 to Figure 20 As shown, the heat sink base material is copper block, with specific dimensions of L=D=10.4mm, H=6mm; the microchannel structure dimensions are h=5000μm, a=100μm, b=700μm, σ =90°, θ =90°, the microchannel aspect ratio is 50, the application of the microchannel radiator is liquid two-phase flow boiling heat transfer, the surface microtexture is designed to be a hydrophobic structure, the surface microtexture size PV=1.7μm, λ=0.6mm. The one-step forming preparation method of the ultra-large aspect ratio microchannel radiator with a microtextured surface comprises the following steps: S1: According to the microchannel substrate structure, an electroplated diamond wire saw with a wire diameter of 80 μm and a wire roller 7 with a wire groove spacing of 700 μm are selected to form a diamond wire saw wire mesh 8, and the corresponding processing trajectory is designed, such as Fig.21 ; S2: Using AB glue as an adhesive to bond the workpiece to the fixing plate 9, and fastening the fixing plate 9 and the worktable 10 together through the grooves of the fixing plate 9 and the worktable 10, so that the workpiece 6 is mounted on the worktable 10 of the diamond wire saw multi-wire cutting machine tool; S3: Import the machining trajectory file of workpiece 6 on the control panel of the diamond wire saw multi-wire cutting machine and set the process parameters: the wire tension is 40N; the Z-axis feed trajectory adopts the linear speed v s =5m / s, workpiece feed speed v fz =0.2mm / min, reciprocating cycle of wire saw T r =150s; Linear velocity at the bottom of the microchannel v s =25m / s, workpiece feed speed v fz =0.0001mm / min, reciprocating cycle of wire saw Tr =150s, so that the workpiece is kept in a state of almost no feeding for 10 minutes, eliminating the feed lag caused by the wire bow, thereby achieving the theoretically designed feed distance and ensuring the processing accuracy; S4: operate the control panel to lower the bottom surface of the workpiece 6 to a position where it will contact the diamond wire saw wire mesh 8, and reset the coordinates of this position to zero as the tool coordinate starting point to complete the tool setting; S5: Run the processing program: The diamond wire saw wire net 8 is driven by the machine tool drive system to perform periodic reciprocating motion, and the workpiece 6 starts to feed according to the introduced processing trajectory. The diamond wire saw wire net 8 contacts the workpiece 6 and starts to scratch and remove the material. During the reciprocating motion of the diamond wire saw wire net, the wire saw will move sideways to form a regular microstructure. Specifically, the processing is divided into two angles of vertical feeding cutting, with the top view showing the top view. l 1 and l 2 Differentiate between step ① and step ②: first, install the microchannel substrate 6 above the middle of the wire saw wire mesh 8, and the front side is parallel to the side of the wire roller; then the workbench 10 is σ Angle rotation, you can start l 1 Corresponding processing; when the designed processing depth is reached, the diamond wire saw wire mesh 8 will stop moving, and the workbench rises back to the coordinate origin, that is, the processing of step ① is completed; then the workbench 10 is carried out l 1 Based on θ Rotate the angle to start l 2 Corresponding processing; reaching the designed processing depth means completing the processing of step ②, and finally realizing the processing of the microchannel structure of the diamond column array with a large aspect ratio; S6: After the processing program is completed, the binder is removed to take out the workpiece 6, which is placed in an ultrasonic alcohol bath for cleaning for 5 minutes and placed in a 50° C. oven for drying for 30 minutes to obtain the final ultra-large aspect ratio microchannel substrate; S7: The ultra-large aspect ratio microchannel substrate 4 is embedded in the liquid flow cavity 5 to fit the two together. The upper cover plate 1 is placed on top of the substrate, and the three are sealed by brazing. Water pipes are connected to the liquid inlet 2 and outlet 3 of the upper cover plate 1, and connected to a water pump to form a circulation loop for liquid convection, and finally a complete ultra-large aspect ratio microchannel radiator with a micro-textured surface is obtained.

[0030] This embodiment adopts σ , θ The angle design, combined with fixed abrasive wire saws and wire rollers of different specifications, can process diamond-shaped micro-column arrays of different angles and sizes, which can play different degrees of fluid lubrication, thermal boundary disturbance and other enhanced heat dissipation effects.

[0031] Example 8 Microchannel heat sink substrate structure Figure 2 and Figure 3 As shown, the microchannel matrix material is made of silicon carbide, taking the specific dimensions L=D=30mm, H=10mm as an example; the microchannel structure dimensions are set to h=8000μm, a=270μm, b=750μm, the microchannel depth-to-width ratio is 29.6, and the application of the microchannel radiator is liquid two-phase flow boiling heat transfer. The surface microtexture is designed to be a hydrophobic structure, and the surface microtexture dimensions are PV=4μm, λ=0.21mm.

[0032] Combination Figure 4 The one-step forming preparation method of the above-mentioned ultra-large aspect ratio microchannel heat sink with a micro-textured surface comprises the following steps: S1: Select active metal chromium coated diamond abrasive wire saw for dry processing. The structure of the active abrasive wire saw is as follows: Fig. 22 As shown, the metal coating 12 is chromium, and the hard abrasive 11 is diamond. The metal chromium can catalyze the phase change of silicon carbide during the process, thereby reducing the difficulty of processing. According to the structure of the microchannel substrate 4, a wire roller 7 with a wire diameter of 250 μm and a wire groove spacing of 750 μm is selected to form a diamond wire saw wire mesh 8, and the corresponding processing trajectory is a straight line in the Z-axis direction. S2: Using AB glue as an adhesive to bond the workpiece 6 to the fixing plate 9, and fastening the fixing plate 9 to the worktable 10 through the grooves of the fixing plate 9 and the worktable 10, so that the workpiece 6 is installed on the worktable 10 of the diamond wire saw multi-wire cutting machine tool; in this embodiment, the workpiece 6 refers to the microchannel substrate to be processed; S3: Import the machining trajectory parameters of workpiece 6 on the control panel of the diamond wire saw multi-wire cutting machine tool and set the process parameters: the wire tension is 40N; the Z-axis feed trajectory adopts the linear speed v s =25m / s, workpiece feed speed v fz =0.15mm / min and wire saw reciprocating cycle T r =85s; Linear velocity at the bottom of the microchannel v s =25m / s, workpiece feed speed v fz =0.0001mm / min, reciprocating cycle of wire saw T r =100s, so that the workpiece is kept in a state of almost no feeding for 10 minutes, eliminating the feed lag caused by the wire bow, thereby achieving the theoretically designed feed distance and ensuring the processing accuracy; S4: operate the control panel to lower the bottom surface of the workpiece 6 to a position where it will contact the diamond wire saw wire mesh 8, and reset the coordinates of this position to zero as the tool coordinate starting point to complete the tool setting; S5: Run the processing program: the diamond wire saw wire net 8 is driven by the machine tool drive system to perform periodic reciprocating motion, the workpiece 6 starts to feed according to the introduced processing trajectory, the diamond wire saw wire net 8 contacts the workpiece 6 and starts to scratch and remove materials, and during the reciprocating motion of the diamond wire saw wire net, the wire saw will move sideways according to the set trajectory route to form a regular microstructure; S6: After the processing program is completed, the binder is removed to take out the workpiece 6, which is placed in an ultrasonic alcohol bath for cleaning for 5 minutes and placed in a 50°C oven for drying for 30 minutes to obtain the final ultra-large aspect ratio microchannel substrate. Figure 5 shown.

[0033] S7: The ultra-large aspect ratio microchannel substrate 4 is embedded in the liquid flow cavity 5 to fit the two together. The upper cover plate 1 is placed on top of the substrate, and the three are sealed by brazing. Water pipes are connected to the liquid inlet 2 and outlet 3 of the upper cover plate 1, and connected to a water pump to form a circulation loop for liquid convection, and finally a complete ultra-large aspect ratio microchannel radiator with a micro-textured surface is obtained.

[0034] In Examples 2 to 8, the use of a fixed abrasive wire saw for reciprocating multi-wire cutting can achieve one-step forming processing of microchannel ultra-large aspect ratio structures and surface microtextures, and the surface microtexture processing does not require additional post-processing steps; the diameter of the cutting tool fixed abrasive wire saw can be as small as 50 microns or less, which is a flexible processing method, and it is easy to achieve ultra-large aspect ratio narrow slit structure processing and thin-walled structures are not easily deformed; the cutting processing temperature of the fixed abrasive wire saw is low, there is no thermal damage during processing, and the microchannel wall will not be deteriorated to reduce the thermal conductivity of the material.

[0035] It should be understood that the above are only preferred implementations of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention.

[0036] The above description of the drawings used in the implementation manner only illustrates certain embodiments of the present invention and should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

Claims

1. A microchannel heat sink with a micro-textured surface, comprising a liquid flow cavity and an upper cover plate attached to the liquid flow cavity, wherein a liquid inlet and an outlet are arranged on both sides of the upper cover plate or the liquid flow cavity; characterized in that: It also includes a microchannel substrate placed in the liquid flow cavity, on which a number of microchannels arranged in a parallel spaced array are formed; the wall of the microchannel is arranged with a periodic microtexture; the structural parameters of the periodic microtexture are precisely designed and processed according to the requirements of the application; when the application is liquid single-phase forced convection heat transfer, the surface periodic microtexture is designed to be a hydrophilic structure that conforms to the Wenzel model to increase the ratio of the wetting area of ​​the fluid to the solid, thereby increasing the heat dissipation area of ​​the microchannel; when the application is liquid two-phase flow boiling heat transfer, the surface periodic microtexture is designed to be a hydrophobic structure that conforms to the Cassie-Baxter model to reduce flow resistance, promote bubble generation and detachment, and enhance the boiling heat transfer coefficient.

2. The microchannel heat sink with a micro-textured surface according to claim 1, characterized in that: The surface profile of the periodic micro-texture is a triangular wave.

3. The microchannel heat sink with a micro-textured surface according to claim 1, characterized in that: The microchannel is provided with one or a combination of rectangular, circular, trapezoidal and wavy microstructures on a cross section perpendicular to the fluid direction.

4. The microchannel heat sink with a micro-textured surface according to claim 3, characterized in that: The microstructures of each group of microchannels are arranged in a plurality along the height direction of the microchannel substrate.

5. The microchannel heat sink with a micro-textured surface according to claim 1, characterized in that: The microchannel substrate comprises a plurality of microcolumns arranged in a parallel and spaced array, the microchannel is formed between adjacent microcolumns, and the cross section of the microcolumns in a direction parallel to the bottom surface of the microchannel substrate is a rhombus.

6. The microchannel heat sink with a micro-textured surface according to claim 1, characterized in that: The ratio of the depth to the width of the microchannel is the aspect ratio, and the aspect ratio is greater than 15.

7. A method for preparing a microchannel heat sink having a micro-textured surface according to any one of claims 1 to 6, characterized in that: The specific steps include: S1: Design the geometric structure and surface microtexture parameters of the microchannel according to the application, select the type of fixed abrasive wire saw and dry and wet processing methods according to the microchannel substrate material, select the specifications of the abrasive wire saw and wire roller according to the microchannel structural parameters, and design the processing trajectory according to the microchannel structure; S2: Mounting the workpiece on a workbench of a fixed abrasive wire saw multi-wire cutting machine; S3: Import the machining trajectory parameters of the workpiece into the bonded abrasive wire saw cutting machine, and set the wire tension and wire speed v s , workpiece feed speed v f and wire saw reciprocating cycle T r :According to the material properties of the workpiece, find the relationship between the microstructure peak-to-valley value PV, wavelength λ and processing parameters: PV= k 1. v f a · v s b · T r c , λ = k 2. v f m · v s n · T r f ; in, k 1. a , b , c is an empirical parameter related to the material. k 2. m , f is approximately equal to 1, n Approximately equal to 0, the processing parameters are inversely calculated; S4: operate the control panel to lower the bottom surface of the workpiece to a position where it will contact the fixed abrasive wire saw wire mesh; S5: Run the machining program: the fixed abrasive wire saw mesh performs periodic reciprocating motion under the drive system of the machine tool, the workpiece starts to be fed, the wire saw mesh contacts the workpiece and starts to remove the material, and during the reciprocating motion of the wire saw mesh, the wire saw forms a regular microstructure through lateral motion; S6: After the processing program is completed, the workpiece is taken out, cleaned, and dried to obtain the final microchannel matrix; S7: Encapsulating the microchannel substrate, the upper cover plate, and the liquid flow cavity to obtain a final microchannel heat sink with an ultra-large aspect ratio and a micro-textured surface.

8. The preparation method according to claim 7, characterized in that: When the microchannel substrate is a non-metallic material with relatively high hardness, the abrasive wire saw in step S1 is an active abrasive wire saw, the wet-dry processing method is dry processing, and the active abrasive can catalyze the phase change of the substrate material under the action of pressure and temperature, thereby reducing the processing difficulty.

9. The preparation method according to claim 7, characterized in that: When a plurality of micro-pillars arranged in a parallel spaced array are processed on the micro-channel substrate, and the cross-section of the micro-pillars in a direction parallel to the bottom surface of the micro-channel substrate is a rhombus, in step S5, the processing is divided into two angles of vertical feed cutting, l 1 and l 2. Distinguish between step ① and step ②: First, install the microchannel substrate above the center of the wire saw wire mesh, and the front side is parallel to the side of the wire roller; then the workbench is rotated at an angle of σ to start l 1 corresponding processing; when the preset processing depth is reached, the wire saw wire mesh stops moving, and the workbench rises back to the coordinate origin, completing the processing of step ①; then the workbench proceeds to l 1 is the reference angle θ, starting with l 2 corresponding processing; when the preset processing depth is reached, the processing of step ② is completed, and finally the processing of the diamond column array microchannel structure is realized.

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