A method of manufacturing a cold plate

Abstract

The application discloses a preparation method of a cold plate, comprising the following steps: coating stopwelding agent on both sides of a single-layer welding area of a to-be-welded cold plate, and not coating the stopwelding agent on a multi-layer welding area of the to-be-welded cold plate; rolling a plurality of to-be-welded cold plates into a composite cold plate structure; placing the composite cold plate structure into a diffusion welding furnace to perform diffusion welding, thereby obtaining a welded composite cold plate structure; performing product leakage detection on the composite cold plate structure; and cutting and separating the multi-layer welding area welded together in the qualified composite cold plate structure, thereby obtaining a plurality of welded cold plates. The method can stack and weld the multi-layer cold plates, improves the heat exchange single-piece diffusion welding efficiency, improves the utilization rate of the diffusion welding furnace, saves the cost, improves the heat exchange single-piece diffusion welding qualified rate, and eliminates the post-welding leakage.

Description

Technical Field

[0001] This invention relates to the field of cold plate production technology, and specifically to a method for preparing a cold plate. Background Technology

[0002] As the heart of an aircraft, the aero-engine is a thermodynamic mechanical device with high requirements for precision and strength, directly affecting the overall performance of the aircraft and reflecting a country's technological, industrial, and defense capabilities. Lightweighting is of great significance for improving the thrust-to-weight ratio, reliability, economy, and safety of aero-engines, and is one of the important research and development indicators for aero-engines.

[0003] Titanium alloy cold plate heat exchangers are made of materials with low density, high specific strength, corrosion resistance and good low-temperature toughness. At the same time, the cold plate is small in size, so it is widely used in the field of heat exchange for aero-engines.

[0004] However, with the booming development of the aero-engine heat exchange field, the demand for such small, thin-walled heat exchange cold plates is constantly increasing. Traditional diffusion welding manufacturing methods can no longer meet market demand. Currently, most of these small and thin-walled heat exchange cold plates are single-layer diffusion welded, and each piece is individually leak-tested after diffusion welding. This manufacturing method results in extremely low utilization of the diffusion welding furnace and consumes a lot of time for leak testing. Summary of the Invention

[0005] Therefore, the technical problem to be solved by this invention is that most small and thin-walled heat exchange cold plates of this type are currently manufactured using single-layer diffusion welding, and each piece is individually leak-tested after diffusion welding. This manufacturing method results in extremely low utilization of the diffusion welding furnace and consumes a lot of time for leak testing.

[0006] Therefore, the present invention provides a method for preparing a cold plate, comprising:

[0007] The first and second tank plates are placed in the pickling solution for pickling.

[0008] After pickling, the first and second slotted plates are placed in the cold plate positioning fixture. The side of the first slotted plate with the first heat dissipation groove and the side of the second slotted plate with the second heat dissipation groove are placed together in the positioning groove and welded to form a cold plate to be welded.

[0009] Remove the cold plate to be welded, apply a weld nugget to both sides of the single-layer welding area of ​​the cold plate to be welded, and do not apply a weld nugget to the multi-layer welding area of ​​the cold plate to be welded.

[0010] Several cold plates to be welded are stacked and rolled into a composite cold plate structure;

[0011] The composite cold plate structure is placed in a diffusion welding furnace for diffusion welding to obtain the welded composite cold plate structure.

[0012] Leak testing is performed on composite cold-rolled steel plate structures.

[0013] The multi-layer welded areas that are welded together in a qualified composite cold plate structure are cut off and separated to obtain several welded cold plates.

[0014] Optionally, the first slot plate includes a first slot plate body and a first welding part. Two first welding parts are provided, and the two first welding parts are provided at both ends on the same side of the first slot plate body. A first heat dissipation groove is formed on the first slot plate. The two ends of the first heat dissipation groove are respectively provided on the two first welding parts.

[0015] The second slot plate includes a second slot plate body and a second welding part. There are two second welding parts, which are located at both ends of the same side of the second slot plate body. A second heat dissipation slot is formed on the second slot plate. The two ends of the second heat dissipation slot are respectively located on the two second welding parts.

[0016] Optionally, the above-mentioned cold plate positioning fixture is provided with a positioning groove for accommodating the first groove plate and the second groove plate, and is provided with a plurality of welding holes, one end of which is connected to the positioning groove.

[0017] The step “Place the first slot plate and the second slot plate into the cold plate positioning fixture and fix them to form a cold plate to be welded” includes: an external welding device passes through the welding hole to weld and fix the first slot plate body and the second slot plate body, and welds and fixes the first welding part and the second welding part.

[0018] The first welding part and the second welding part are welded together to form a multi-layer welding area; the first groove plate and the second groove plate are welded together to form a single-layer welding area.

[0019] Optionally, the above step of "applying solder resist to both sides of the single-layer welding area" includes:

[0020] Apply masking tape to the side of the first welding part away from the first heat sink and the side of the second welding part away from the second heat sink; spray anti-weld agent on both sides of the cold plate to be welded; remove the masking tape.

[0021] Optionally, the coating thickness of the aforementioned anti-welding agent is less than or equal to 0.01 mm.

[0022] Optionally, the above step of "diffusion welding the composite cold plate structure" includes:

[0023] The composite cold-plate structure was placed in a diffusion welding furnace, the furnace door was closed, and a vacuum was drawn to 10°C. -2Pa and above; heat the composite cold plate structure and keep it at that temperature; after the composite cold plate structure body reaches the preset temperature, perform pressure welding; keep the pressure for a preset time.

[0024] Optionally, the above-mentioned step of "heating and holding the composite cold plate structure" includes: heating to 350°C in a diffusion welding furnace and holding for 60 minutes; heating to 700°C in a diffusion welding furnace and holding for 90 minutes; and heating to 900°C in a diffusion welding furnace and holding for 100 minutes.

[0025] Optionally, the above step "pressure welding is performed after the composite cold-rolled plate structure body reaches the preset temperature" includes:

[0026] Once the temperature of the composite cold plate structure reaches 900℃, start timing and pressurize. Set the pressure to 3-5MPa and hold for 60 minutes.

[0027] Optionally, the aforementioned cold plate is further provided with two detection holes, which penetrate the cold plate and are respectively connected to both ends of the heat dissipation channel formed by the first heat dissipation groove and the second heat dissipation groove.

[0028] The step "product leak detection of composite cold plate structure" includes: welding a needle valve to the top surface of the composite cold plate structure after diffusion welding, with the bottom end of the needle valve connected to the detection hole, connecting one side of the needle valve to an airtightness testing device and the other side to a pressure gauge, and filling the detection hole with air; ensuring that the heat dissipation channel in the composite cold plate structure after diffusion welding is in an airtight environment of 3MPa for pressure maintenance; if the product has no deformation and no leakage, it is marked as qualified; if the product has leakage or deformation, it is marked as unqualified.

[0029] Optionally, the pickling solution described above includes hydrofluoric acid, nitric acid, and water, with a hydrofluoric acid:nitric acid:water ratio of 0.96:4.74:94.3.

[0030] The technical solution provided by this invention has the following advantages:

[0031] 1. The method for preparing a cold plate provided by the present invention includes: immersing a first grooved plate and a second grooved plate in an acid pickling solution for acid pickling; placing the acid-pickled first grooved plate and the second grooved plate into a cold plate positioning fixture, placing the side of the first grooved plate with a first heat dissipation groove and the side of the second grooved plate with a second heat dissipation groove facing each other and placing them in the positioning groove, and welding them to form a cold plate to be welded; removing the cold plate to be welded, applying a weld resist to both sides of the single-layer welding area of ​​the cold plate to be welded, and not applying a weld resist to the multi-layer welding area of ​​the cold plate to be welded; rolling several cold plates to be welded into a composite cold plate structure; placing the composite cold plate structure into a diffusion welding furnace for diffusion welding to obtain a welded composite cold plate structure; performing leak testing on the composite cold plate structure; and cutting and separating the multi-layer welding areas welded together in the qualified composite cold plate structure to obtain several welded cold plates.

[0032] This method allows for the stacking and welding of multiple layers of cold-rolled plates. Using this method, multiple parts can be welded in a single batch and multiple parts can be inspected for leaks simultaneously, thus saving significant time and costs. It also ensures a high success rate for diffusion welding.

[0033] 2. The first and second tank plates are pickled using an acid pickling solution to remove the dense oxide film on the surface, revealing a silvery-white metallic luster. The pickling solution includes hydrofluoric acid, nitric acid, and water, with a hydrofluoric acid:nitric acid:water ratio of 0.96:4.74:94.3. The pickling time is one minute. Since diffusion welding requires a free oxide layer on the surface of the parts, the presence of an oxide layer would hinder the diffusion between atoms in the diffusion welding process. Simultaneously, this concentration ratio and pickling time ensure that the oxide layer is just removed without corroding the substrate, laying the foundation for obtaining a high-quality diffusion weld joint.

[0034] 3. After the welding of the composite cold plate structure completed by the present invention, all thirty layers of multiple welding areas are welded together. Therefore, the detection holes opened on the multi-layer welding areas are welded and fixed to form two vertical detection channels. Two needle valves are welded to the top surface of the composite cold plate structure after diffusion welding. These two needle valves are fixed to the two detection holes, and the bottom ports of the two needle valves are connected to the detection holes, so that the two needle valves are connected to the detection channels. One side of the needle valve is connected to the air tightness testing equipment, and the other side is connected to the pressure gauge. One needle valve is used as the air inlet, and the other needle valve is kept sealed. Gas is slowly injected into one of the detection channels through the air tightness testing equipment. The gas can simultaneously inject gas into the heat dissipation channels in the thirty-layer cold plate, ensuring that the heat dissipation channels in the composite cold plate structure after diffusion welding are in an airtight environment of 3MPa, and the pressure is maintained for 15 minutes. If the product has no deformation and no leakage, it is marked as qualified. If the product has leakage or deformation, it is marked as unqualified. Masking tape is used for protection, and multi-layer welding and single-layer welding are separated. Leak detection of multi-layer cold plates can be performed simultaneously, which improves the quality inspection efficiency. Attached Figure Description

[0035] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0036] Figure 1 A flowchart illustrating the method for preparing the cold plate provided by this invention;

[0037] Figure 2 A schematic diagram of the structure of the cold plate to be welded in the cold plate preparation method provided by the present invention;

[0038] Figure 3 A schematic diagram of the cold plate positioning fixture in the cold plate preparation method provided by the present invention;

[0039] Figure 4 A schematic diagram of the structure in the method for preparing a cold plate provided by the present invention, in which the cold plate to be welded is installed in a cold plate positioning fixture;

[0040] Figure 5 A schematic diagram of the structure of attaching masking tape to the multi-layer welding area of ​​the cold plate to be welded in the cold plate preparation method provided by the present invention;

[0041] Figure 6 A schematic diagram of the structure of the cold plate to be welded with a masking tape attached and the cold plate to be welded sprayed with a weld stop agent in the cold plate preparation method provided by the present invention;

[0042] Figure 7 This is a schematic diagram of the composite cold plate structure provided by the present invention;

[0043] Figure 8 A schematic diagram of the composite cold plate structure provided by the present invention placed between the upper and lower pressure heads;

[0044] Figure 9 A schematic diagram of the structure between the upper and lower pressure heads for placing multiple composite cold plates provided by the present invention;

[0045] Figure 10 A schematic diagram of a conventional diffusion welding structure with an uneven upper pressure head provided by the present invention;

[0046] Figure 11 A schematic diagram of the diffusion welding temperature rise curve provided by the present invention;

[0047] Figure 12 This invention provides an installation diagram of the needle valve and the composite cold plate structure;

[0048] Explanation of reference numerals in the attached figures:

[0049] 1 – Cold plate to be welded; 11 – Single-layer welding area; 12 – Multi-layer welding area; 13 – Inspection hole;

[0050] 2 – Cold plate positioning fixture; 21 – Positioning groove; 22 – Welding hole;

[0051] 31 – Upper pressure head; 32 – Lower pressure head; 33 – Welding fixture;

[0052] 4 - Composite cold-rolled steel plate structure; 41 - Perforated side plate;

[0053] 5 - Needle valve. Detailed Implementation

[0054] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0055] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for 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 the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0056] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0057] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0058] Example

[0059] This embodiment provides a method for preparing a cold plate, such as... Figures 1 to 12As shown, the following are required: a cold plate positioning fixture 2 and a pressurizing device. The shape of the cold plate positioning fixture 2 is consistent with the shape of the cold plate 1 to be welded. Taking this embodiment as an example, the cold plate 1 to be welded is U-shaped, and the cold plate positioning fixture 2 is also U-shaped. The outer dimensions of the cold plate positioning fixture 2 are larger than those of the cold plate positioning fixture 2. A positioning groove 21 is provided on one side of the cold plate positioning fixture 2. The shape and size of the positioning groove 21 are the same as those of the cold plate positioning fixture 2. Several welding holes 22 are provided at the edge of the positioning groove 21. One end of the welding hole 22 is connected to the positioning groove 21, and the other end is connected to the outside. In this application, as shown... Figure 3 As shown, welding holes 22 are provided on both sides of the upper end, both sides and the bottom end of the positioning groove 21.

[0060] like Figure 8 As shown, the pressurizing device includes an upper pressure head 31 and a lower pressure head 32. The opposing surfaces of the upper pressure head 31 and the lower pressure head 32 are both horizontal. The cold plate 1 to be welded is placed between the upper pressure head 31 and the lower pressure head 32 for welding. If necessary, a graphite welding fixture 33 can be placed between the upper pressure head 31 and the lower pressure head 32.

[0061] The cold plate 1 to be welded is assembled from a first slotted plate and a second slotted plate. In this embodiment, both the first and second slotted plates are U-shaped. Two first welding parts are fixed to both ends of the first slotted plate body on the same side. A first heat dissipation groove is formed on one side of the first slotted plate, with its two ends respectively located on the two first welding parts. The middle portion of the first heat dissipation groove is formed on the first slotted plate body. Similarly, two second welding parts are fixed to both ends of the second slotted plate body on the same side. A second heat dissipation groove is formed on one side of the second slotted plate, with its two ends respectively located on the two first welding parts. The middle portion of the second heat dissipation groove is formed on the second slotted plate body. The shapes of the first and second heat dissipation grooves are compatible. The side of the first slotted plate with the first heat dissipation groove and the side of the second slotted plate with the second heat dissipation groove are then fitted together, and the first and second welding parts are also fitted together to form the cold plate 1 to be welded.

[0062] Furthermore, each of the two first welding parts is provided with a first through hole, and each of the two second welding parts is provided with a second through hole. The two first through holes and the two second through holes are arranged in a one-to-one correspondence to form two detection holes 13.

[0063] It should be noted that the cold plate, the cold plate positioning fixture 2, and the positioning groove 21 can be of any shape, and are not limited to the U-shape mentioned above. The three must be set accordingly.

[0064] like Figure 1 As shown, the method for preparing the cold plate provided in this embodiment specifically includes the following steps:

[0065] S1. The first and second tank plates are pickled using an acid pickling solution to remove the dense oxide film on the surface, revealing a silvery-white metallic luster. The pickling solution includes hydrofluoric acid, nitric acid, and water, with a hydrofluoric acid:nitric acid:water ratio of 0.96:4.74:94.3. The pickling time is one minute. Since diffusion welding requires a free oxide layer on the surface of the parts, the presence of an oxide layer would hinder the diffusion between atoms in the diffusion welding process. Simultaneously, this concentration ratio and pickling time ensure that the oxide layer is just removed without corroding the substrate, laying the foundation for obtaining a high-quality diffusion weld joint.

[0066] S2. Assemble the cold plate 1 to be welded. (Example) Figures 2 to 4 As shown, the first slot plate is placed in the positioning groove 21 with the side facing away from the first heat dissipation slot towards the bottom of the positioning groove 21. Then, the second slot plate with the side having the second heat dissipation slot facing the first slot plate is placed in the positioning groove 21. At this time, the first and second heat dissipation slots are correspondingly attached together, and they can cooperate to form heat dissipation pipes to achieve heat dissipation function. The first and second welding parts are also attached together. Through the welding hole 22, an external welding device is used to perform high-precision spot welding between the first and second slot plates, and high-precision spot welding is performed between the first and second welding parts, thereby positioning the shape of the first and second slot plates. The first welding part and the second welding part are welded to form a multi-layer welding area 12; the first slot plate and the second slot plate are welded to form a single-layer welding area 11.

[0067] The first slot plate and the first welded part form the upper slot plate, and the second slot body and the second welded part form the lower slot plate. The single-sided gap between the positioning groove 21 and the upper and lower slot plates must not exceed 0.02mm. By using micro-arc cold welding to position the product shape, it is ensured that the upper and lower slot plates are not misaligned. This ensures the accurate connection of the heat dissipation channel between the first and second slot plates, effectively reducing the defect rate.

[0068] S3. Apply solder resist to both sides of the single-layer welding area 11. For example... Figure 5 and Figure 6 As shown, masking tape is applied to both the side of the first welded part facing away from the first heat sink and the side of the second welded part facing away from the second heat sink. Generally, the width of the first and second welded parts is 8mm. Double-sided application is required to ensure a secure bond and that there are no missed areas.

[0069] Next, apply a weld stop agent to the surface of the single-layer welding area 11, namely the first and second groove plates, using a spray gun. The thickness of the weld stop agent should not exceed 0.01mm. After spraying, remove the masking tape to ensure that the area where the masking tape is pasted, namely the multi-layer welding area 12, does not receive the weld stop agent.

[0070] S4. Several cold-rolled steel plate composite layers are stacked and rolled into a composite cold-rolled steel plate structure 4. For example... Figure 7 As shown, the titanium alloy heat exchange cold plate that has been spot-welded and positioned is stacked and fixed by its shape positioning to form a composite cold plate structure 4. The number of stacked layers is thirty layers and shall not exceed thirty layers. Two layers of non-perforated side plate 41 fixtures are placed at the bottom of the thirty-layer composite cold plate structure 4. The surface of the non-perforated side plate 41 fixtures also needs to be sprayed with anti-welding agent before stacking.

[0071] S5. Perform diffusion welding on the composite cold plate structure 4. For example... Figures 8 to 11 As shown, the composite cold plate structure 4 is placed in a diffusion welding furnace, the furnace door is closed, and a vacuum is drawn to 10°C. -2 Heating begins when the temperature exceeds a certain level (e.g., Pa). The temperature inside the diffusion welding furnace is increased to 350℃ in 30 minutes and held for 60 minutes; then increased to 700℃ in 30 minutes and held for 90 minutes; finally, increased to 900℃ in 10 minutes and held for 100 minutes. Once the monitored temperature reaches 900℃, timing begins, and pressure is applied at a rate of 0.05 mm / min, with a pressure set at 3-5 MPa. After holding the pressure for 60 minutes, the equipment can be cooled. This results in a welded cold-plate composite structure. Because the multi-layer welding areas 12 (i.e., the first and second welding parts) are not coated with weld resist, while the single-piece welding areas (i.e., the first and second groove plate bodies) are coated with weld resist, all thirty layers of welding areas are welded together after welding. The single-piece welding areas are simply the first and second groove plate bodies of a single cold plate welded together; adjacent cold plates are not welded together.

[0072] In this embodiment, by observing the displacement of the equipment, the total displacement of the cold plate is ensured to be 1.5mm.

[0073] 900℃ and 3-5MPa are the optimal temperature and pressure for diffusion welding of this material. Multi-stage heating ensures complete heat penetration and prevents the core temperature from being too low, which could affect diffusion welding. A slow pressing speed of 0.05mm / min and a deformation of 1.5mm facilitate atomic diffusion during the diffusion welding process. By using these optimal process parameters, a reliable diffusion weld can be achieved.

[0074] S6. Perform leak testing on the composite cold plate structure 4 after diffusion welding. As shown in step S5, after welding is completed, the multiple welding areas of the thirty layers are all welded together; therefore, the inspection holes 13 opened on the multi-layer welding area 12 are welded and fixed to form two vertical inspection channels. Figure 12As shown, two needle valves 5 are welded to the top surface of the composite cold plate structure 4 after diffusion welding. These two needle valves 5 are fixed to the two detection holes 13. The bottom openings of the two needle valves 5 are connected to the detection holes 13, so that the two needle valves 5 are connected to the detection channels. One side of the needle valve 5 is connected to the air tightness testing equipment, and the other side is connected to the pressure gauge. One of the needle valves 5 is used as the air inlet, and the other needle valve 5 is kept sealed. Gas is slowly injected into one of the detection channels through the air tightness testing equipment. The gas can simultaneously inject gas into the heat dissipation channels in the thirty-layer cold plate, ensuring that the heat dissipation channels in the composite cold plate structure 4 after diffusion welding are in an airtight environment of 3MPa, and the pressure is maintained for 15 minutes. If the product has no deformation and no leakage, it is marked as qualified. If the product has leakage or deformation, it is marked as unqualified.

[0075] Using the above method, multiple parts can be welded in one furnace and multiple parts can be leak-tested at once, thus saving a significant amount of time and cost. It also ensures a high pass rate for diffusion welding. Specifically, it allows for simultaneous airtightness testing of thirty layers of cold-rolled steel plates, greatly improving production efficiency. This method allows for the stacking and welding of thirty layers of cold-rolled steel plates, improving the efficiency of diffusion welding on individual heat exchanger plates, increasing the utilization rate of the diffusion welding furnace, and saving costs. It also improves the pass rate of diffusion welding on individual heat exchanger plates and eliminates post-weld leakage. Using masking tape for protection, it allows for zoned processing of multi-layer and single-layer welding, and enables simultaneous leak testing of multiple layers of cold-rolled steel plates, improving quality inspection efficiency.

[0076] In other feasible embodiments, multiple composite cold plate structures 4 can be placed between the upper pressure head 31 and the lower pressure head 32, utilizing methods such as... Figure 9 As shown, five can be arranged between the upper pressure head 31 and the lower pressure head 32. A welding fixture 33 can also be placed between the upper pressure head 31 and the lower pressure head 32, with five composite cold plate structures 4 placed above and below the welding fixture 33, improving production efficiency. When installing the welding fixture 33, since the thickness of a single cold plate is 1.6mm, the required single-piece diffusion welding deformation is 0.05mm. Therefore, the parallelism and flatness requirements for the equipment pressure head, welding fixture 33 (upper pressure head 31 and lower pressure head 32), and graphite plate (welding fixture 33) are extremely strict to avoid product defects. Figure 10 If the weld is not properly sealed, the airtightness test will result in leakage.

[0077] Meanwhile, when thirty layers of cold plates are stacked and welded, the deformation of a single piece is still 0.05mm, and the total deformation is 1.5mm. This eliminates the effects of equipment head tilt and unevenness, and ensures that all welded surfaces are ultimately subjected to full force.

[0078] In other feasible methods, before placing the composite cold plate structure 4 into the diffusion welding furnace, a non-perforated side plate is also fixed at the top of the composite cold plate structure. A through hole is also opened on the non-perforated side plate above the composite cold plate structure 4 corresponding to the detection hole. The through hole is connected to the detection hole, and the through hole and the detection hole together form a detection channel. Solder stop flux is applied to the non-perforated side plate. When it is necessary to use a needle valve for leak detection, the needle valve needs to be installed in the through hole on the non-perforated side plate. The detection channel is used to detect all thirty layers of cold plates at the same time, avoiding the scrapping of the top cold plate during conventional testing and reducing production costs.

[0079] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for preparing a cold plate, characterized in that, include: The first and second tank plates are placed in the pickling solution for pickling. After pickling, the first and second slot plates are placed in the cold plate positioning fixture (2). The side of the first slot plate with the first heat dissipation groove and the side of the second slot plate with the second heat dissipation groove are placed together in the positioning groove (21) and welded to form the cold plate to be welded (1). Take out the cold plate (1) to be welded, apply anti-weld agent to both sides of the single-layer welding area (11) of the cold plate (1) to be welded, and do not apply anti-weld agent to the multi-layer welding area (12) of the cold plate (1); Several cold plates to be welded (1) are laminated and rolled into a composite cold plate structure (4). The composite cold plate structure (4) is placed in a diffusion welding furnace for diffusion welding to obtain the welded composite cold plate structure (4). Leak testing was performed on the composite cold plate structure (4); The multi-layer welding area (12) welded together in the qualified composite cold plate structure (4) is cut off and separated to obtain several welded cold plates; The first slot plate includes a first slot plate body and a first welding part. Two first welding parts are provided, and the two first welding parts are located at both ends of the same side of the first slot plate body. A first heat dissipation groove is formed on the first slot plate. The two ends of the first heat dissipation groove are respectively located on the two first welding parts. The second slot plate includes a second slot plate body and a second welding part. There are two second welding parts, which are located at both ends of the same side of the second slot plate body. A second heat dissipation slot is formed on the second slot plate. The two ends of the second heat dissipation slot are respectively located on the two second welding parts. The first welding part and the second welding part are welded to form a multi-layer welding area (12); the first groove plate body and the second groove plate body are welded to form a single-layer welding area (11). Two first welding parts are provided with first through holes, and two second welding parts are provided with second through holes. The two first through holes and the two second through holes are arranged in a one-to-one correspondence to form two detection holes (13).

2. The method for preparing a cold plate according to claim 1, characterized in that, The cold plate positioning fixture (2) is provided with a positioning groove (21) for accommodating the first groove plate and the second groove plate, and a plurality of welding holes (22) are provided, one end of the welding hole (22) being connected to the positioning groove (21); The step "Place the first slot plate and the second slot plate into the cold plate positioning fixture (2) and fix them to form the cold plate to be welded (1)" includes: an external welding device passing through the welding hole (22) to weld and fix the first slot plate body and the second slot plate body, and to weld and fix the first welding part and the second welding part.

3. The method for preparing a cold plate according to claim 2, characterized in that, The step "applying solder resist to both sides of the single-layer welding area (11)" includes: Adhere masking tape to the side of the first welding part away from the first heat sink and the side of the second welding part away from the second heat sink; spray anti-weld agent on both sides of the cold plate (1) to be welded; remove the masking tape.

4. The method for preparing a cold plate according to claim 3, characterized in that, The thickness of the anti-welding agent sprayed is less than or equal to 0.01 mm.

5. The method for preparing a cold plate according to claim 4, characterized in that, The step "diffusion welding of the composite cold plate structure (4)" includes: The composite cold plate structure (4) was placed in a diffusion welding furnace, the furnace door was closed, and a vacuum was drawn to 10. -2 Pa; Heating and heat-preserving the composite cold plate structure (4); Pressure welding is performed after the composite cold plate structure (4) reaches the preset temperature; Preset pressure holding time.

6. The method for preparing a cold plate according to claim 5, characterized in that, The step "heating and holding the composite cold plate structure (4)" includes: heating to 350°C in the diffusion welding furnace and holding for 60 minutes; heating to 700°C in the diffusion welding furnace and holding for 90 minutes; heating to 900°C in the diffusion welding furnace and holding for 100 minutes.

7. The method for preparing a cold plate according to claim 5, characterized in that, Step "After the composite cold plate structure (4) body reaches the preset temperature, pressure welding is performed" includes: When the temperature of the composite cold plate structure (4) reaches 900℃, start timing and pressurize. Set the pressure to 3-5MPa and hold for 60min.

8. The method for preparing a cold plate according to claim 5, characterized in that, The detection hole (13) penetrates the cold plate, and the two detection holes (13) are respectively connected to the two ends of the heat dissipation channel formed by the first heat dissipation groove and the second heat dissipation groove; The step "product leak detection of composite cold plate structure (4)" includes: welding a needle valve (5) to the top surface of the composite cold plate structure (4) after diffusion welding, the bottom end of the needle valve (5) being connected to the detection hole (13), one side of the needle valve (5) being connected to an airtightness testing device, and the other side being connected to a pressure gauge, and filling the detection hole (13) with air; ensuring that the heat dissipation channel in the composite cold plate structure (4) after diffusion welding is in an airtight environment of 3MPa for pressure maintenance; if the product has no deformation and no leakage, it is marked as qualified; if the product has leakage or deformation, it is marked as unqualified.

9. The method for preparing a cold plate according to any one of claims 1-8, characterized in that, The pickling solution comprises hydrofluoric acid, nitric acid, and water, with a hydrofluoric acid:nitric acid:water ratio of 0.96:4.74:94.3.

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