Vacuum brazing clamp and method for water-cooled disc

Abstract

The invention discloses a vacuum brazing clamp and method for a water-cooled disc, and aims to overcome the defects that in the brazing process of the water-cooled disc, the clamping force of a tool on the water-cooled disc is not uniform, the temperature difference between the interior of a furnace and the water-cooled disc is large due to the fact that the tool absorbs much heat, and the brazing effect is affected. The water cooling disc comprises an upper tool pressing plate and a lower tool pressing plate which are connected together, the water cooling disc comprises a bottom disc and a cover plate, brazing filler metal pieces are loaded between the bottom disc and the cover plate, an upper heat insulation frame and a lower heat insulation frame are arranged between the upper tool pressing plate and the lower tool pressing plate, an upper thin plate is installed between the cover plate and the upper heat insulation frame, and a lower thin plate is installed between the bottom disc and the lower heat insulation frame. And the cold water plate is clamped between the upper thin plate and the lower thin plate. According to the vacuum brazing clamp for the water-cooling disc, the water-cooling disc brazing part can be prevented from being in direct contact with the tool plate, the heating and cooling effects of the brazing part in the brazing process are improved, and the uniformity of the pressure and the uniformity of the temperature during clamping of the brazing part are optimized.

Description

Technical Field

[0001] The invention relates to a welding tool, and more particularly to a water cooling plate vacuum brazing fixture and method. Background Art

[0002] Aluminum alloys are widely used in the manufacture of high-efficiency heat dissipation devices due to their excellent mechanical and thermal conductivity, such as water cooling plates in the semiconductor industry. Vacuum brazing is suitable for welding large-area and complex flat welds. The welded products have high precision, small deformation, good weld corrosion resistance, and long service life. It is the most critical process in the production of aluminum plate-fin radiators, water cooling plates, chassis and other products.

[0003] The aluminum water cooling plate is used as part of the test tube module and is cooled with an external circulating water pump. Its structure mainly consists of a base with water channels and a cover plate. Its structural characteristics are built-in water channels and complex welding surface structure. Therefore, the aluminum water cooling plate is suitable for welding using vacuum brazing.

[0004] During the brazing process of aluminum water-cooling plates, the aluminum water-cooling plates are clamped and positioned using tooling. During this process, the tooling absorbs a lot of heat, and the deformation of the tooling has a great impact on the pressure uniformity of the brazed parts. The heating and cooling rates of the brazed parts are extremely low, causing the brazed parts to be in the high temperature zone for too long, resulting in defects such as brazing filler metal flow and dissolution. In the early stage of aluminum alloy vacuum brazing tests, this scheme was used for brazing. When the furnace temperature and the workpiece temperature differed by less than 10°C, the workpiece heating rate was lower than 0.1°C / min, and the brazing filler metal flow and dissolution occurred frequently during the brazing process, greatly affecting the brazing effect. In addition, the original tooling is in contact with the brazed parts over a large area, which places high requirements on the tooling rigidity, the processing accuracy and clamping accuracy of the brazed parts, and the corresponding cost is also increased. Summary of the invention

[0005] In order to overcome the above-mentioned shortcomings, the present invention provides a water-cooling plate vacuum brazing fixture and method, which avoids the water-cooling plate brazing parts from directly contacting the tooling plate, improves the heating and cooling effects of the brazing parts during the brazing process, optimizes the uniformity of pressure and temperature of the brazing parts during clamping, reduces the requirements for the processing accuracy of the brazing parts, improves the qualified brazing rate, reduces the brazing time, and reduces the cost.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions: a water-cooled plate vacuum brazing fixture, comprising an upper tooling plate and a lower tooling plate connected together, the water-cooled plate comprising a chassis and a cover plate, a brazing sheet is loaded between the chassis and the cover plate, an upper insulation frame and a lower insulation frame are arranged between the upper tooling plate and the lower tooling plate, an upper thin plate is installed between the cover plate and the upper insulation frame, a lower thin plate is installed between the chassis and the lower insulation frame, and the cold water plate is clamped between the upper thin plate and the lower thin plate.

[0007] The base plate and cover plate of the water cooling plate are brazed with brazing sheet to form a whole. Before brazing, the brazing sheet is loaded between the base plate and cover plate of the water cooling plate, and then the assembled water cooling plate is placed between the upper thin plate and the lower thin plate, and then the upper tooling pressure plate and the lower tooling pressure plate are connected together.

[0008] An upper thin plate and an upper insulation frame are used to separate the upper surface of the water cooling plate and the upper tooling pressure plate, and a lower thin plate and a lower insulation frame are used to separate the lower surface of the water cooling plate and the lower tooling pressure plate, so as to avoid direct contact between the water cooling plate and the upper tooling pressure plate and the lower tooling pressure plate, thereby improving the heating and cooling effects of the water cooling plate during the brazing process and optimizing the uniformity of the pressure on the water cooling plate during clamping.

[0009] The clamping force between the upper tooling pressure plate and the lower tooling pressure plate acts on the upper thin plate and the lower thin plate. The upper thin plate and the lower thin plate have large areas, and the upper and lower surfaces of the cold water tray are completely in contact with the upper and lower thin plates. The clamping force is evenly distributed to various positions of the cold water tray, optimizing the uniformity of the pressure on the water cooling tray clamping.

[0010] The water-cooling plate vacuum brazing fixture of this patent application can prevent the water-cooling plate brazing parts from directly contacting the tooling plate, improve the heating and cooling effects of the brazing parts during the brazing process, optimize the uniformity of the pressure and temperature of the brazing parts during clamping, reduce the requirements for the processing accuracy of the brazing parts, improve the qualified brazing rate, reduce the brazing time, and reduce costs.

[0011] Preferably, fastening rods are connected between the upper tooling pressure plate and the lower tooling pressure plate, and the fastening rods are arranged at intervals on the periphery of the water cooling plate.

[0012] The fastening rod connects the upper tooling platen and the lower tooling platen together, making the assembly and disassembly of the upper tooling platen and the lower tooling platen quick and easy. The fastening rods are arranged at intervals around the periphery of the water cooling plate, so that the clamping force is dispersed around the periphery of the water cooling plate, which is conducive to the uniformity of the pressure on the water cooling plate during clamping.

[0013] Preferably, a step surface is provided on the fastening rod, one end of the fastening rod is threadedly connected to a locking ring, a limit head is provided at the other end of the fastening rod, and the locking ring is connected to a pre-tensioning spring; the pre-tensioning spring abuts against the upper surface of the upper tooling pressure plate, a fine-tuning gap is formed between the step surface and the lower surface of the upper tooling pressure plate, and the limit head abuts against the lower surface of the lower tooling pressure plate; or, the pre-tensioning spring abuts against the lower surface of the lower tooling pressure plate, a fine-tuning gap is formed between the step surface and the upper surface of the lower tooling pressure plate, and the limit head abuts against the upper surface of the upper tooling pressure plate.

[0014] After the upper tooling platen and the lower tooling platen are connected, the preload spring provides preload force between the upper tooling platen and the lower tooling platen. Due to the existence of the fine-tuning gap, there is a movable fine-tuning spacing between the upper tooling platen and the lower tooling platen. During the brazing process, the brazing sheet is heated and melted. At this time, under the action of the preload spring, the upper tooling platen and the lower tooling platen are close to each other to squeeze the molten brazing material, ensuring that the brazing material is fully distributed between the chassis and the cover plate, thereby improving the brazing effect.

[0015] Preferably, a plurality of heat dissipation holes are densely distributed on the upper tooling pressing plate and the lower tooling pressing plate.

[0016] The setting of heat dissipation holes can reduce weight, reduce the heat absorption of the upper and lower tooling pressure plates during vacuum brazing, accelerate heat conduction, improve the heating efficiency of the cold water plate, ensure that the temperature difference between the furnace temperature and the cold water plate is within 10°C, the heating rate of the water cooling plate is maintained above 0.3°C / min, and the cooling rate is above 0.5°C / min, so as to avoid the cold water plate being in the solder melting point range for a long time, reduce solder overflow and prevent the formation of welding corrosion defects.

[0017] Preferably, the upper insulation frame and the lower insulation frame each include a plurality of pipes arranged at equal intervals.

[0018] The pipe fittings have a hollow structure, which can speed up the conduction of heat and improve the heating efficiency of the cold water pan, ensuring that the temperature difference between the furnace temperature and the cold water pan is within 10°C, the heating rate of the water cooling pan is maintained above 0.3°C / min, and the cooling rate is above 0.5°C / min, so as to avoid the cold water pan being in the solder melting point range for a long time, reduce solder overflow and prevent the formation of welding corrosion defects.

[0019] The combination of pipe fittings and upper and lower thin plates can effectively adjust the uniformity of tooling pressure, wherein the thin-walled pipe fittings play a role similar to a spring and reduce the influence of deformation of the upper and lower tooling pressure plates on pressure uniformity, thereby reducing the requirements for tooling rigidity.

[0020] In another solution, both the upper heat insulation frame and the lower heat insulation frame include a plurality of support plates arranged at equal intervals, and compression springs are connected to the support plates near both ends.

[0021] The upper insulation frame and the lower insulation frame both include a number of support plates and compression springs connected to the support plates, which are conducive to the rapid transfer of heat in the furnace to the cold water pan and improve the heating efficiency of the cold water pan. The compression spring provides preload force to the cold water pan. During the brazing process, the brazing sheet melts due to heat. At this time, under the action of the compression spring, the molten brazing material can be squeezed to a certain extent, ensuring that the brazing material is fully distributed between the bottom plate and the cover plate, thereby improving the brazing effect.

[0022] A water cooling plate vacuum brazing method is provided, which utilizes a water cooling plate vacuum brazing fixture to clamp the water cooling plate, and comprises the following steps: S1, pickling the water cooling plate; S2, cutting a brazing sheet; S3, flatly placing the brazing sheet between a bottom plate and a cover plate and clamping it; S4, placing the assembled water cooling plate between an upper thin plate and a lower thin plate, and then connecting an upper tooling pressing plate and a lower tooling pressing plate together; S5, installing a temperature measuring thermocouple on the side wall of the cold water plate; S6, placing the clamped cold water plate into a vacuum brazing furnace, and evacuating the furnace; S7, heating and keeping the vacuum brazing furnace warm to achieve brazing of the cold water plate; S8, cooling the vacuum brazing furnace; S9, taking out the cold water plate.

[0023] The cold water plate is pickled to remove surface oil and oxide layer. Cut the sheet of aluminum alloy brazing material to make the shape of the brazing material consistent with the shape of the brazing surface, and wipe the brazing material with anhydrous ethanol and a dust-free cloth to remove surface dirt. Use the upper thin plate and the upper insulation frame to separate the upper surface of the water cooling plate and the upper tooling plate, and use the lower thin plate and the lower insulation frame to separate the lower surface of the water cooling plate and the lower tooling plate to avoid direct contact between the water cooling plate and the upper tooling plate. This improves the heating and cooling effects of the water cooling plate during brazing and optimizes the uniformity of the pressure on the water cooling plate clamp.

[0024] The clamping force between the upper tooling pressure plate and the lower tooling pressure plate acts on the upper thin plate and the lower thin plate. The upper thin plate and the lower thin plate have large areas, and the upper and lower surfaces of the cold water tray are completely in contact with the upper and lower thin plates. The clamping force is evenly distributed to various positions of the cold water tray, optimizing the uniformity of the pressure on the water cooling tray clamping.

[0025] As a preference, the vacuum degree in the S6 vacuum brazing furnace is greater than 5*10 -2 pa.

[0026] The vacuum parameters of vacuum brazing are set reasonably to ensure the brazing effect.

[0027] Preferably, the temperature in the S7 vacuum brazing furnace is 582°C-584°C, and the temperature of the water cooling plate is controlled to be greater than 575°C for a total time of 50-60 minutes.

[0028] The temperature in the vacuum furnace is controlled within a reasonable range to ensure the temperature of the cold water pan. The insulation time is set within a certain range to ensure the reliability of the brazing of the chassis and cover.

[0029] Preferably, S8 first cools the vacuum brazing furnace by circulating water, and after the temperature in the furnace drops to 420°C, high-purity nitrogen is filled in to accelerate cooling; after the temperature of the furnace body drops below 60°C, air is filled in the furnace to make the air pressure inside and outside the furnace consistent.

[0030] The cooling process is carried out in multiple stages. In the first stage, the vacuum brazing furnace is directly cooled by water circulation to lower the temperature of the entire brazing vacuum furnace. In the second stage, high-purity nitrogen is filled to accelerate cooling and quickly reduce the temperature to 60°C. In the third stage, air is filled to make the temperature and air pressure inside and outside the furnace consistent. Finally, the brazing-finished water-cooling plate can be taken out to ensure the brazing effect of the water-cooling plate.

[0031] Compared with the prior art, the present invention has the following beneficial effects: (1) The water-cooling plate vacuum brazing fixture of the present patent application can prevent the water-cooling plate brazing parts from directly contacting the tooling plate, thereby improving the heating and cooling effects of the brazing parts during the brazing process, optimizing the uniformity of the pressure and temperature of the brazing parts during the clamping, reducing the requirements for the processing accuracy of the brazing parts, improving the qualified brazing rate, reducing the brazing time, and reducing the cost; (2) The pipe fittings are hollow structures, which can accelerate the conduction of heat, improve the heating efficiency of the cold water plate, ensure that the temperature difference between the furnace temperature and the cold water plate is within 10°C, and the heating rate of the water-cooling plate is maintained. The temperature is maintained above 0.3℃ / min and the cooling rate is maintained above 0.5℃ / min to prevent the cold water pan from being in the solder melting point range for a long time, reduce solder overflow and prevent the formation of welding corrosion defects; (3) The combination of pipe fittings and upper and lower thin plates can effectively adjust the uniformity of tooling pressure. The thin-walled pipe fittings play a role similar to a spring and reduce the influence of the deformation of the upper and lower tooling pressure plates on the pressure uniformity, thereby reducing the requirements for tooling rigidity; (4) During the brazing process, the brazing sheet is melted and squeezed by the heat, ensuring that the solder is fully distributed between the base plate and the cover plate, thereby improving the brazing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a structural schematic diagram of the present invention.

[0033] Figure 2 It is an exploded view of the present invention.

[0034] Figure 3 It is a cross-sectional view of Example 1 of the present invention.

[0035] Figure 4 Schematic diagram of the connection of the fastening rods of Embodiment 2 of the present invention.

[0036] Figure 5 It is a cross-sectional view of Example 3 of the present invention.

[0037] In the figure: 1. upper tooling pressure plate, 2. lower tooling pressure plate, 3. heat dissipation hole, 4. chassis, 5. cover plate, 6. water channel, 7. upper insulation frame, 8. lower insulation frame, 9. upper thin plate, 10. lower thin plate, 11. fastening rod, 12. locking ring, 13. limit head, 14. step surface, 15. preload spring, 16. fine-tuning gap, 17. solder sheet, 18. pipe fitting, 19. support plate, 20. compression spring. DETAILED DESCRIPTION

[0038] The technical solution of the present invention is further described in detail below through specific embodiments and in conjunction with the accompanying drawings: Example 1: A water cooling plate vacuum brazing fixture (see attached Figure 1 To Attachment Figure 3 ), including an upper tooling platen 1 and a lower tooling platen 2 connected together, and a plurality of heat dissipation holes 3 are densely distributed on the upper tooling platen 1 and the lower tooling platen 2, and the heat dissipation holes 3 are square holes. The upper tooling platen 1 and the lower tooling platen 2 are both made of stainless steel, and the thickness is about 50mm. The water cooling plate includes a chassis 4 and a cover plate 5, a water channel 6 is arranged on the chassis 4, and the cover plate 5 is connected to the chassis 4 to cover the water channel 6, and a brazing sheet 17 is loaded between the chassis 4 and the cover plate 5, an upper insulation frame 7 and a lower insulation frame 8 are arranged between the upper tooling platen 1 and the lower tooling platen 2, an upper thin plate 9 is installed between the cover plate 5 and the upper insulation frame 7, and a lower thin plate 10 is installed between the chassis 4 and the lower insulation frame 8, and the cold water plate is clamped between the upper thin plate 9 and the lower thin plate 10. The upper thin plate 9 and the lower thin plate 10 are both made of stainless steel, with a thickness of 2~3mm, and the outer contour size is 5-10mm larger than the outer contour size of the water cooling plate. After the fixture is clamped, the gap between the upper thin plate 9 and the lower thin plate 10 and the surface of the cold water tray is ≤0.03mm, and the assembly gap of the cold water tray is ≤0.02mm.

[0039] A fastening rod 11 is connected between the upper tooling platen 1 and the lower tooling platen 2, and the fastening rod 11 is arranged at intervals on the periphery of the water cooling plate. A plurality of connecting holes are arranged at the outer edge positions of the upper tooling platen 1 and the lower tooling platen 2, and the fastening rod 11 is connected to the connecting holes. One end of the fastening rod 11 is threadedly connected to the locking ring 12, and a limit head 13 is arranged at the other end of the fastening rod 11. The limit head 13 abuts on the lower surface of the lower tooling platen 2, and the locking ring 12 abuts on the upper surface of the upper tooling platen 1. The fastening rod 11 connects the upper tooling platen 1 and the lower tooling platen 2 together, so that the assembly and disassembly of the upper tooling platen 1 and the lower tooling platen 2 are convenient and quick. The fastening rods 11 are arranged at intervals on the periphery of the water cooling plate, so that the clamping force is dispersed on the periphery of the water cooling plate, which is beneficial to the uniformity of the pressure on the water cooling plate clamping.

[0040] The upper insulation frame 7 and the lower insulation frame 8 both include a number of pipe fittings 18 arranged at equal intervals. The pipe fittings 18 are square pipes with a wall thickness of about 3 mm. The vertical dimensions are kept as consistent as possible, with a deviation of no more than 0.1 mm. The length dimension is larger than the outer contour dimensions of the upper thin plate 9 and the lower thin plate 10. The square pipes are placed at the same interval, with a spacing of 8 to 10 mm. The upper part of the pipe fittings 18 of the upper insulation frame 7 fits with the upper tooling plate 1, and the lower part of the pipe fittings 18 fits with the upper thin plate 9. The upper part of the pipe fittings 18 of the lower insulation frame 8 fits with the lower thin plate 10, and the lower part of the pipe fittings 18 fits with the lower tooling plate 2.

[0041] The heat dissipation holes 3 on the upper tooling plate 1 and the lower tooling plate 2 can reduce weight and reduce the heat absorption of the upper tooling plate 1 and the lower tooling plate 2 during vacuum brazing. The hollow structure of the pipe 18 and the heat dissipation holes 3 can accelerate the conduction of heat and improve the heating efficiency of the cold water plate, ensuring that the temperature difference between the furnace temperature and the cold water plate is within 10°C, the heating rate of the water cooling plate is maintained at more than 0.3°C / min, and the cooling rate is maintained at more than 0.5°C / min, so as to avoid the cold water plate being in the melting point range of the solder for a long time, reduce the solder overflow and prevent the formation of welding corrosion defects.

[0042] A water cooling plate vacuum brazing method is provided, which uses a water cooling plate vacuum brazing fixture to clamp the water cooling plate, and comprises the following steps: S1, pickling the water cooling plate, ultrasonically cleaning aluminum water cooling plate parts to remove oil stains, pickling to remove oxide layers, and finally rinsing with clean water and drying.

[0043] S2, cutting the brazing material sheet 17; cutting the sheet-shaped aluminum alloy brazing material sheet 17 so that the shape of the brazing material sheet 17 is consistent with the shape of the brazing surface, and using anhydrous ethanol and a dust-free cloth to wipe the brazing material to remove surface dirt.

[0044] S3, place the solder sheet 17 flatly between the bottom plate 4 and the cover plate 5 and clamp them.

[0045] S4, place the assembled water cooling plate between the upper thin plate 9 and the lower thin plate 10, and then connect the upper tooling plate 1 and the lower tooling plate 2 together. During operation, the lower heat insulation frame 8 is placed on the lower tooling plate 2, and then the lower thin plate 10 is placed on the lower heat insulation frame 8, and then the assembled water cooling plate is placed on the lower thin plate 10, the upper thin plate 9 is placed on the assembled water cooling plate, the upper heat insulation frame 7 is placed on the upper thin plate 9, and the upper tooling plate 1 is placed on the upper heat insulation frame 7, and finally the upper tooling plate 1 and the lower tooling plate 2 are fastened together by the fastening rod 11.

[0046] S5. Install a temperature measuring thermocouple on the side wall of the cold water pan.

[0047] S6, put the clamped cold water tray into the vacuum brazing furnace, and evacuate the furnace; the vacuum degree in the vacuum brazing furnace is greater than 5*10 -2 pa.

[0048] S7, heating and keeping the vacuum brazing furnace warm to achieve brazing of the cold water plate; the temperature in the vacuum brazing furnace is 582°C~584°C, and the temperature of the water cooling plate is controlled to be greater than 575°C for a total time of 50~60 minutes.

[0049] S8, cooling the vacuum brazing furnace; firstly cool the vacuum brazing furnace by circulating water, and after the temperature in the furnace drops to 420°C, fill it with high-purity nitrogen to accelerate cooling; after the temperature of the furnace body drops below 60°C, fill the furnace with air to make the air pressure inside and outside the furnace consistent.

[0050] S9, take out the cold water pan.

[0051] The cold water plate is pickled to remove surface oil and oxide layer. Cut the sheet aluminum alloy brazing sheet 17 so that the shape of the brazing sheet 17 is consistent with the shape of the brazing surface, and wipe the brazing sheet 17 with anhydrous ethanol and a dust-free cloth to remove surface dirt. Use the upper thin plate 9 and the upper insulation frame 7 to separate the upper surface of the water cooling plate and the upper tooling plate 1, and use the lower thin plate 10 and the lower insulation frame 8 to separate the lower surface of the water cooling plate and the lower tooling plate 2 to prevent the water cooling plate from directly contacting the upper tooling plate 1 and the lower tooling plate 2, thereby improving the heating and cooling effects of the water cooling plate during brazing and optimizing the uniformity of the pressure on the water cooling plate clamp.

[0052] The clamping force between the upper tooling plate 1 and the lower tooling plate 2 acts on the upper thin plate 9 and the lower thin plate 10. The upper thin plate 9 and the lower thin plate 10 have large areas, and the upper and lower surfaces of the cold water tray are completely in contact with the upper and lower thin plates 9 and 10. The clamping force is evenly distributed to various positions of the cold water tray, optimizing the uniformity of the pressure on the water cooling tray clamping.

[0053] The cooling process is carried out in multiple stages. In the first stage, the vacuum brazing furnace is directly cooled by water circulation to lower the temperature of the entire brazing vacuum furnace. In the second stage, high-purity nitrogen is filled to accelerate cooling and quickly reduce the temperature to 60°C. In the third stage, air is filled to make the temperature and air pressure inside and outside the furnace consistent. Finally, the brazing-finished water-cooling plate can be taken out to ensure the brazing effect of the water-cooling plate.

[0054] Example 2: A water cooling plate vacuum brazing fixture (see attached Figure 1 , Attachment Figure 2 , Attachment Figure 4 ), including an upper tooling platen 1 and a lower tooling platen 2 connected together, and a plurality of heat dissipation holes 3 are densely distributed on the upper tooling platen 1 and the lower tooling platen 2, and the heat dissipation holes 3 are square holes. The upper tooling platen 1 and the lower tooling platen 2 are both made of stainless steel, and the thickness is about 50mm. The water cooling plate includes a chassis 4 and a cover plate 5, a water channel 6 is arranged on the chassis 4, and the cover plate 5 is connected to the chassis 4 to cover the water channel 6, and a brazing sheet 17 is loaded between the chassis 4 and the cover plate 5, an upper insulation frame 7 and a lower insulation frame 8 are arranged between the upper tooling platen 1 and the lower tooling platen 2, an upper thin plate 9 is installed between the cover plate 5 and the upper insulation frame 7, and a lower thin plate 10 is installed between the chassis 4 and the lower insulation frame 8, and the cold water plate is clamped between the upper thin plate 9 and the lower thin plate 10. The upper thin plate 9 and the lower thin plate 10 are both made of stainless steel, with a thickness of 2~3mm, and the outer contour size is 5-10mm larger than the outer contour size of the water cooling plate. After the fixture is clamped, the gap between the upper thin plate 9 and the lower thin plate 10 and the surface of the cold water tray is ≤0.03mm, and the assembly gap of the cold water tray is ≤0.02mm.

[0055] A fastening rod 11 is connected between the upper tooling platen 1 and the lower tooling platen 2, and the fastening rod 11 is arranged at intervals on the periphery of the water cooling plate. A plurality of connecting holes are arranged at the outer edge positions of the upper tooling platen 1 and the lower tooling platen 2, and the fastening rod 11 is connected to the connecting holes. One end of the fastening rod 11 is threadedly connected to the locking ring 12, and a limit head 13 is arranged at the other end of the fastening rod 11. The limit head 13 abuts on the lower surface of the lower tooling platen 2, and the locking ring 12 abuts on the upper surface of the upper tooling platen 1. The fastening rod 11 connects the upper tooling platen 1 and the lower tooling platen 2 together, so that the assembly and disassembly of the upper tooling platen 1 and the lower tooling platen 2 are convenient and quick. The fastening rods 11 are arranged at intervals on the periphery of the water cooling plate, so that the clamping force is dispersed on the periphery of the water cooling plate, which is beneficial to the uniformity of the pressure on the water cooling plate clamping.

[0056] A step surface 14 is provided on the fastening rod 11, one end of the fastening rod 11 is threadedly connected to the locking ring 12, a limit head 13 is provided at the other end of the fastening rod 11, the locking ring 12 is connected to the pre-tightening spring 15, a spring mounting groove is provided on the end surface of the locking ring 12, and one end of the pre-tightening spring 15 is installed in the spring mounting groove; the pre-tightening spring 15 abuts against the upper surface of the upper tooling pressure plate 1, a fine-tuning gap 16 is formed between the step surface 14 and the lower surface of the upper tooling pressure plate 1, and the limit head 13 abuts against the lower surface of the lower tooling pressure plate 2; or, the pre-tightening spring 15 abuts against the lower surface of the lower tooling pressure plate 2, a fine-tuning gap 16 is formed between the step surface 14 and the upper surface of the lower tooling pressure plate 2, and the limit head 13 abuts against the upper surface of the upper tooling pressure plate 1.

[0057] In this embodiment, the preload spring 15 abuts against the upper surface of the upper tooling platen 1, a fine-tuning gap 16 is formed between the step surface 14 and the lower surface of the upper tooling platen 1, and the limit head 13 abuts against the lower surface of the lower tooling platen 2. A groove is set on the upper surface of the upper tooling platen 1, and the lower end of the preload spring 15 is installed in the groove. After the upper tooling platen 1 and the lower tooling platen 2 are connected, the preload spring 15 provides a preload force between the upper tooling platen 1 and the lower tooling platen 2. Due to the existence of the fine-tuning gap 16, there is a movable fine-tuning spacing between the upper tooling platen 1 and the lower tooling platen 2. During the brazing process, the brazing sheet is melted by heat. At this time, under the action of the preload spring 15, the upper tooling platen 1 and the lower tooling platen 2 are close to each other to extrude the molten brazing material, ensuring that the brazing material is fully distributed between the chassis 4 and the cover plate 5, thereby improving the brazing effect.

[0058] The upper insulation frame 7 and the lower insulation frame 8 both include a number of pipe fittings 18 arranged at equal intervals. The pipe fittings 18 are square pipes with a wall thickness of about 3 mm. The vertical dimensions are kept as consistent as possible, with a deviation of no more than 0.1 mm. The length dimension is larger than the outer contour dimensions of the upper thin plate 9 and the lower thin plate 10. The square pipes are placed at the same interval, with a spacing of 8 to 10 mm. The upper part of the pipe fittings 18 of the upper insulation frame 7 fits with the upper tooling plate 1, and the lower part of the pipe fittings 18 fits with the upper thin plate 9. The upper part of the pipe fittings 18 of the lower insulation frame 8 fits with the lower thin plate 10, and the lower part of the pipe fittings 18 fits with the lower tooling plate 2.

[0059] The heat dissipation holes 3 on the upper tooling plate 1 and the lower tooling plate 2 can reduce weight and reduce the heat absorption of the upper tooling plate 1 and the lower tooling plate 2 during vacuum brazing. The hollow structure of the pipe 18 and the heat dissipation holes 3 can accelerate the conduction of heat and improve the heating efficiency of the cold water plate, ensuring that the temperature difference between the furnace temperature and the cold water plate is within 10°C, the heating rate of the water cooling plate is maintained at more than 0.3°C / min, and the cooling rate is maintained at more than 0.5°C / min, so as to avoid the cold water plate being in the melting point range of the solder for a long time, reduce the solder overflow and prevent the formation of welding corrosion defects.

[0060] A water cooling plate vacuum brazing method is provided, which uses a water cooling plate vacuum brazing fixture to clamp the water cooling plate, and comprises the following steps: S1, pickling the water cooling plate, ultrasonically cleaning aluminum water cooling plate parts to remove oil stains, pickling to remove oxide layers, and finally rinsing with clean water and drying.

[0061] S2, cutting the brazing material sheet 17; cutting the sheet-shaped aluminum alloy brazing material sheet 17 so that the shape of the brazing material sheet 17 is consistent with the shape of the brazing surface, and using anhydrous ethanol and a dust-free cloth to wipe the brazing material to remove surface dirt.

[0062] S3, place the solder sheet 17 flatly between the bottom plate 4 and the cover plate 5 and clamp them.

[0063] S4, place the assembled water cooling plate between the upper thin plate 9 and the lower thin plate 10, and then connect the upper tooling plate 1 and the lower tooling plate 2 together. During operation, the lower heat insulation frame 8 is placed on the lower tooling plate 2, and then the lower thin plate 10 is placed on the lower heat insulation frame 8, and then the assembled water cooling plate is placed on the lower thin plate 10, the upper thin plate 9 is placed on the assembled water cooling plate, the upper heat insulation frame 7 is placed on the upper thin plate 9, and the upper tooling plate 1 is placed on the upper heat insulation frame 7, and finally the upper tooling plate 1 and the lower tooling plate 2 are fastened together by the fastening rod 11.

[0064] S5. Install a temperature measuring thermocouple on the side wall of the cold water pan.

[0065] S6, put the clamped cold water tray into the vacuum brazing furnace, and evacuate the furnace; the vacuum degree in the vacuum brazing furnace is greater than 5*10 -2 pa.

[0066] S7, heating and keeping the vacuum brazing furnace warm to achieve brazing of the cold water plate; the temperature in the vacuum brazing furnace is 582°C~584°C, and the temperature of the water cooling plate is controlled to be greater than 575°C for a total time of 50~60 minutes.

[0067] S8, cooling the vacuum brazing furnace; firstly cool the vacuum brazing furnace by circulating water, and after the temperature in the furnace drops to 420°C, fill it with high-purity nitrogen to accelerate cooling; after the temperature of the furnace body drops below 60°C, fill the furnace with air to make the air pressure inside and outside the furnace consistent.

[0068] S9, take out the cold water pan.

[0069] The cold water plate is pickled to remove surface oil and oxide layer. Cut the sheet aluminum alloy brazing sheet 17 so that the shape of the brazing sheet 17 is consistent with the shape of the brazing surface, and wipe the brazing sheet 17 with anhydrous ethanol and a dust-free cloth to remove surface dirt. Use the upper thin plate 9 and the upper insulation frame 7 to separate the upper surface of the water cooling plate and the upper tooling plate 1, and use the lower thin plate 10 and the lower insulation frame 8 to separate the lower surface of the water cooling plate and the lower tooling plate 2 to prevent the water cooling plate from directly contacting the upper tooling plate 1 and the lower tooling plate 2, thereby improving the heating and cooling effects of the water cooling plate during brazing and optimizing the uniformity of the pressure on the water cooling plate clamp.

[0070] The clamping force between the upper tooling plate 1 and the lower tooling plate 2 acts on the upper thin plate 9 and the lower thin plate 10. The upper thin plate 9 and the lower thin plate 10 have large areas, and the upper and lower surfaces of the cold water tray are completely in contact with the upper and lower thin plates 9 and 10. The clamping force is evenly distributed to various positions of the cold water tray, optimizing the uniformity of the pressure on the water cooling tray clamping.

[0071] The cooling process is carried out in multiple stages. In the first stage, the vacuum brazing furnace is directly cooled by water circulation to lower the temperature of the entire brazing vacuum furnace. In the second stage, high-purity nitrogen is filled to accelerate cooling and quickly reduce the temperature to 60°C. In the third stage, air is filled to make the temperature and air pressure inside and outside the furnace consistent. Finally, the brazing-finished water-cooling plate can be taken out to ensure the brazing effect of the water-cooling plate.

[0072] Embodiment 3: A water cooling plate vacuum brazing fixture (attached Figure 4 , Attachment Figure 5), including an upper tooling platen 1 and a lower tooling platen 2 connected together, and a plurality of heat dissipation holes 3 are densely distributed on the upper tooling platen 1 and the lower tooling platen 2, and the heat dissipation holes 3 are square holes. The upper tooling platen 1 and the lower tooling platen 2 are both made of stainless steel, and the thickness is about 50mm. The water cooling plate includes a chassis 4 and a cover plate 5, a water channel 6 is arranged on the chassis 4, and the cover plate 5 is connected to the chassis 4 to cover the water channel 6, and a brazing sheet 17 is loaded between the chassis 4 and the cover plate 5, an upper insulation frame 7 and a lower insulation frame 8 are arranged between the upper tooling platen 1 and the lower tooling platen 2, an upper thin plate 9 is installed between the cover plate 5 and the upper insulation frame 7, and a lower thin plate 10 is installed between the chassis 4 and the lower insulation frame 8, and the cold water plate is clamped between the upper thin plate 9 and the lower thin plate 10. The upper thin plate 9 and the lower thin plate 10 are both made of stainless steel, with a thickness of 2~3mm, and the outer contour size is 5-10mm larger than the outer contour size of the water cooling plate. After the fixture is clamped, the gap between the upper thin plate 9 and the lower thin plate 10 and the surface of the cold water tray is ≤0.03mm, and the assembly gap of the cold water tray is ≤0.02mm.

[0073] A fastening rod 11 is connected between the upper tooling platen 1 and the lower tooling platen 2, and the fastening rod 11 is arranged at intervals on the periphery of the water cooling plate. A plurality of connecting holes are arranged at the outer edge positions of the upper tooling platen 1 and the lower tooling platen 2, and the fastening rod 11 is connected to the connecting holes. One end of the fastening rod 11 is threadedly connected to the locking ring 12, and a limit head 13 is arranged at the other end of the fastening rod 11. The limit head 13 abuts on the lower surface of the lower tooling platen 2, and the locking ring 12 abuts on the upper surface of the upper tooling platen 1. The fastening rod 11 connects the upper tooling platen 1 and the lower tooling platen 2 together, so that the assembly and disassembly of the upper tooling platen 1 and the lower tooling platen 2 are convenient and quick. The fastening rods 11 are arranged at intervals on the periphery of the water cooling plate, so that the clamping force is dispersed on the periphery of the water cooling plate, which is beneficial to the uniformity of the pressure on the water cooling plate clamping.

[0074] A step surface 14 is provided on the fastening rod 11, one end of the fastening rod 11 is threadedly connected to the locking ring 12, a limit head 13 is provided at the other end of the fastening rod 11, the locking ring 12 is connected to the pre-tightening spring 15, a spring mounting groove is provided on the end surface of the locking ring 12, and one end of the pre-tightening spring 15 is installed in the spring mounting groove; the pre-tightening spring 15 abuts against the upper surface of the upper tooling pressure plate 1, a fine-tuning gap 16 is formed between the step surface 14 and the lower surface of the upper tooling pressure plate 1, and the limit head 13 abuts against the lower surface of the lower tooling pressure plate 2; or, the pre-tightening spring 15 abuts against the lower surface of the lower tooling pressure plate 2, a fine-tuning gap 16 is formed between the step surface 14 and the upper surface of the lower tooling pressure plate 2, and the limit head 13 abuts against the upper surface of the upper tooling pressure plate 1.

[0075] In this embodiment, the preload spring 15 abuts against the upper surface of the upper tooling platen 1, a fine-tuning gap 16 is formed between the step surface 14 and the lower surface of the upper tooling platen 1, and the limit head 13 abuts against the lower surface of the lower tooling platen 2. A groove is set on the upper surface of the upper tooling platen 1, and the lower end of the preload spring 15 is installed in the groove. After the upper tooling platen 1 and the lower tooling platen 2 are connected, the preload spring 15 provides a preload force between the upper tooling platen 1 and the lower tooling platen 2. Due to the existence of the fine-tuning gap 16, there is a movable fine-tuning spacing between the upper tooling platen 1 and the lower tooling platen 2. During the brazing process, the brazing sheet is melted by heat. At this time, under the action of the preload spring 15, the upper tooling platen 1 and the lower tooling platen 2 are close to each other to extrude the molten brazing material, ensuring that the brazing material is fully distributed between the chassis 4 and the cover plate 5, thereby improving the brazing effect.

[0076] The upper insulation frame 7 and the lower insulation frame 8 each include a plurality of support plates 19 arranged at equal intervals, and compression springs 20 are connected to the support plates 19 near both ends. The compression spring 20 of the upper insulation frame 7 is connected to the upper tooling plate 1, and the compression spring 20 of the lower insulation frame 8 is connected to the lower tooling plate 2. The width of the entire row of support plates 19 increases from the middle to both ends to ensure that the contact area of ​​all support plates 19 and the cold water pan is equal, which is conducive to the uniformity of the clamping force on the cold water pan.

[0077] The upper insulation frame 7 and the lower insulation frame 8 both include a plurality of support plates 19 and a compression spring 20 connected to the support plates 19, which is conducive to the rapid transfer of heat in the furnace to the cold water pan and improves the heating efficiency of the cold water pan. The compression spring 20 provides a preload force to the cold water pan. During the brazing process, the brazing sheet is heated and melted. At this time, under the action of the compression spring 20, the molten brazing material can be squeezed to a certain extent, ensuring that the brazing material is fully distributed between the bottom plate 4 and the cover plate 5, thereby improving the brazing effect.

[0078] The arrangement of the heat dissipation holes 3 on the upper tooling platen 1 and the lower tooling platen 2 can reduce weight and reduce the heat absorption of the upper tooling platen 1 and the lower tooling platen 2 during vacuum brazing. The arrangement of the support plate 19 and the heat dissipation holes 3 can accelerate heat conduction and improve the heating efficiency of the cold water plate, ensuring that the temperature difference between the furnace temperature and the cold water plate is within 10°C, the heating rate of the water cooling plate is maintained at more than 0.3°C / min, and the cooling rate is maintained at more than 0.5°C / min, so as to avoid the cold water plate being in the melting point range of the solder for a long time, reduce solder overflow and prevent the formation of welding corrosion defects.

[0079] A water cooling plate vacuum brazing method is provided, which uses a water cooling plate vacuum brazing fixture to clamp the water cooling plate, and comprises the following steps: S1, pickling the water cooling plate, ultrasonically cleaning aluminum water cooling plate parts to remove oil stains, pickling to remove oxide layers, and finally rinsing with clean water and drying.

[0080] S2, cutting the brazing material sheet 17; cutting the sheet-shaped aluminum alloy brazing material sheet 17 so that the shape of the brazing material sheet 17 is consistent with the shape of the brazing surface, and using anhydrous ethanol and a dust-free cloth to wipe the brazing material to remove surface dirt.

[0081] S3, place the solder sheet 17 flatly between the bottom plate 4 and the cover plate 5 and clamp them.

[0082] S4, place the assembled water cooling plate between the upper thin plate 9 and the lower thin plate 10, and then connect the upper tooling plate 1 and the lower tooling plate 2 together. During operation, the lower heat insulation frame 8 is placed on the lower tooling plate 2, and then the lower thin plate 10 is placed on the lower heat insulation frame 8, and then the assembled water cooling plate is placed on the lower thin plate 10, the upper thin plate 9 is placed on the assembled water cooling plate, the upper heat insulation frame 7 is placed on the upper thin plate 9, and the upper tooling plate 1 is placed on the upper heat insulation frame 7, and finally the upper tooling plate 1 and the lower tooling plate 2 are fastened together by the fastening rod 11.

[0083] S5. Install a temperature measuring thermocouple on the side wall of the cold water pan.

[0084] S6, put the clamped cold water tray into the vacuum brazing furnace, and evacuate the furnace; the vacuum degree in the vacuum brazing furnace is greater than 5*10 -2 pa.

[0085] S7, heating and keeping the vacuum brazing furnace warm to achieve brazing of the cold water plate; the temperature in the vacuum brazing furnace is 582°C~584°C, and the temperature of the water cooling plate is controlled to be greater than 575°C for a total time of 50~60 minutes.

[0086] S8, cooling the vacuum brazing furnace; firstly cool the vacuum brazing furnace by circulating water, and after the temperature in the furnace drops to 420°C, fill it with high-purity nitrogen to accelerate cooling; after the temperature of the furnace body drops below 60°C, fill the furnace with air to make the air pressure inside and outside the furnace consistent.

[0087] S9, take out the cold water pan.

[0088] The cold water plate is pickled to remove surface oil and oxide layer. Cut the sheet aluminum alloy brazing sheet 17 so that the shape of the brazing sheet 17 is consistent with the shape of the brazing surface, and wipe the brazing sheet 17 with anhydrous ethanol and a dust-free cloth to remove surface dirt. Use the upper thin plate 9 and the upper insulation frame 7 to separate the upper surface of the water cooling plate and the upper tooling plate 1, and use the lower thin plate 10 and the lower insulation frame 8 to separate the lower surface of the water cooling plate and the lower tooling plate 2 to prevent the water cooling plate from directly contacting the upper tooling plate 1 and the lower tooling plate 2, thereby improving the heating and cooling effects of the water cooling plate during brazing and optimizing the uniformity of the pressure on the water cooling plate clamp.

[0089] The clamping force between the upper tooling plate 1 and the lower tooling plate 2 acts on the upper thin plate 9 and the lower thin plate 10. The upper thin plate 9 and the lower thin plate 10 have large areas, and the upper and lower surfaces of the cold water tray are completely in contact with the upper and lower thin plates 9 and 10. The clamping force is evenly distributed to various positions of the cold water tray, optimizing the uniformity of the pressure on the water cooling tray clamping.

[0090] The cooling process is carried out in multiple stages. In the first stage, the vacuum brazing furnace is directly cooled by water circulation to lower the temperature of the entire brazing vacuum furnace. In the second stage, high-purity nitrogen is filled to accelerate cooling and quickly reduce the temperature to 60°C. In the third stage, air is filled to make the temperature and air pressure inside and outside the furnace consistent. Finally, the brazing-finished water-cooling plate can be taken out to ensure the brazing effect of the water-cooling plate.

[0091] The above-described embodiments are only preferred solutions of the present invention and are not intended to limit the present invention in any form. Other variations and modifications are possible without exceeding the technical solutions described in the claims.

Claims

1. A water cooling plate vacuum brazing fixture, characterized in that: It includes an upper tooling platen and a lower tooling platen connected together, the water cooling plate includes a chassis and a cover plate, a brazing sheet is loaded between the chassis and the cover plate, an upper insulation frame and a lower insulation frame are arranged between the upper tooling platen and the lower tooling platen, an upper thin plate is installed between the cover plate and the upper insulation frame, a lower thin plate is installed between the chassis and the lower insulation frame, and the cold water plate is clamped between the upper thin plate and the lower thin plate.

2. A water cooling plate vacuum brazing fixture according to claim 1, characterized in that: The upper tooling pressure plate and the lower tooling pressure plate are connected with fastening rods, and the fastening rods are arranged at intervals on the periphery of the water cooling plate.

3. A water cooling plate vacuum brazing fixture according to claim 2, characterized in that: A step surface is arranged on the fastening rod, one end of the fastening rod is threadedly connected to a locking ring, a limit head is arranged on the other end of the fastening rod, and the locking ring is connected to a pre-tensioning spring; the pre-tensioning spring abuts against the upper surface of the upper tooling pressure plate, a fine-tuning gap is formed between the step surface and the lower surface of the upper tooling pressure plate, and the limit head abuts against the lower surface of the lower tooling pressure plate; or, the pre-tensioning spring abuts against the lower surface of the lower tooling pressure plate, a fine-tuning gap is formed between the step surface and the upper surface of the lower tooling pressure plate, and the limit head abuts against the upper surface of the upper tooling pressure plate.

4. The water cooling plate vacuum brazing fixture according to claim 1 is characterized in that: The upper tooling pressing plate and the lower tooling pressing plate are densely covered with a plurality of heat dissipation holes.

5. A water cooling plate vacuum brazing fixture according to any one of claims 1 to 4, characterized in that: The upper heat insulation frame and the lower heat insulation frame both include a plurality of pipe fittings arranged at equal intervals.

6. A water cooling plate vacuum brazing fixture according to any one of claims 1 to 4, characterized in that: The upper heat-insulating frame and the lower heat-insulating frame both include a plurality of support plates arranged at equal intervals, and compression springs are connected to the positions near both ends of the support plates.

7. A water cooling plate vacuum brazing method, characterized in that: The water-cooling plate is clamped by using the water-cooling plate vacuum brazing fixture described in any one of claims 1 to 6, comprising the following steps: S1, pickling the water-cooling plate; S2, cutting the brazing sheet; S3, placing the brazing sheet flatly between the bottom plate and the cover plate and clamping it; S4, placing the assembled water-cooling plate between the upper thin plate and the lower thin plate, and then connecting the upper tooling pressure plate and the lower tooling pressure plate together; S5, installing a temperature measuring thermocouple on the side wall of the cold water plate; S6, placing the clamped cold water plate into a vacuum brazing furnace and evacuating the furnace; S7, heating and keeping the vacuum brazing furnace warm to achieve brazing of the cold water plate; S8, cooling the vacuum brazing furnace; S9, taking out the cold water plate.

8. The water cooling plate vacuum brazing method according to claim 7, characterized in that S6 The vacuum degree in the vacuum brazing furnace is greater than 5*10 -2 pa.

9. The water cooling plate vacuum brazing method according to claim 7, characterized in that: The temperature in the S7 vacuum brazing furnace is 582℃~584℃, and the temperature of the water cooling plate is controlled to be greater than 575℃ for a total time of 50~60min.

10. The water cooling plate vacuum brazing method according to claim 7, characterized in that: S8 first cools the vacuum brazing furnace by circulating water. After the temperature inside the furnace drops to 420°C, high-purity nitrogen is filled in to accelerate cooling. After the temperature of the furnace body drops below 60°C, air is filled in the furnace to make the air pressure inside and outside the furnace consistent.

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