A Low-Deformation Diffusion Welding Method for Multi-Layer Complex Flow Channel Aluminum Alloy Gas Isostatic Structure

Abstract

This invention provides a low-deformation diffusion welding method for multi-layer complex flow channel aluminum alloy uniform gas structure, which is applicable to the manufacturing and inspection of multi-layer complex flow channel aluminum alloy uniform gas structure. It solves the technical problem of high-quality diffusion welding of multi-layer aluminum alloy structure, solves the problem of positional displacement of pores before and after welding, and solves the problem of weld sealing inspection of multi-layer complex flow channel aluminum alloy uniform gas structure.

Description

Technical Field

[0001] This invention relates to a low-deformation diffusion welding method for multi-layer complex flow channel aluminum alloy uniform gas structure, belonging to the field of aluminum alloy processing and welding technology. Background Technology

[0002] Currently, there are many welding methods for aluminum alloys, mainly including TIG welding, friction stir welding, and electron beam welding, all of which can achieve good results. However, for plate-type multi-layer welded aluminum alloy structures, where the welding surface is a large plane and welding between multiple planes is required, the above welding methods are difficult to implement for such planar structures. Brazing and diffusion welding, on the other hand, can effectively achieve the welding of such plate-type multi-layer planar structures.

[0003] For complex flow channel aluminum alloy gas uniform structures, surface treatment is generally required after precision machining to meet usage requirements. However, during brazing, the filler metal reacts with the base material, causing changes in the chemical composition of the base material near the brazed joint. This can lead to problems such as poor localized surface treatment or inconsistent surface treatment results between the brazed joint area and other areas. Furthermore, improper brazing process control can cause weld beads and erosion within the internal flow channels of the gas uniform structure, resulting in uneven gas flow and affecting its usability. Therefore, diffusion welding is generally used for complex flow channel aluminum alloy gas uniform structures. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: the present invention provides a low-deformation diffusion welding method for multi-layer complex flow channel aluminum alloy uniform gas structure, which is applicable to the manufacturing and testing of multi-layer complex flow channel aluminum alloy uniform gas structure, and solves the technical problem of high-quality diffusion welding of multi-layer aluminum alloy structure, solves the problem of positional displacement of pores before and after welding, and solves the problem of weld sealing test of multi-layer complex flow channel aluminum alloy uniform gas structure.

[0005] The technical solution adopted in this invention is as follows:

[0006] A low-deformation diffusion welding method for multi-layer complex flow channel aluminum alloy gas homogenization structures includes:

[0007] (1) Process the pre-welding blanks of the upper plate, middle plate and lower plate according to the product structure. The air vent of the lower plate is a blind hole, and the allowance is left unprocessed.

[0008] (2) Pickling is performed on the pre-welding blanks of the upper, middle and lower layers to ensure that the welding surfaces are clean and free of oil.

[0009] (3) Based on the ratio of the welding area between the upper and middle layers and between the middle and lower layers, select either a multi-stage welding scheme or a single-stage welding scheme, and perform welding according to the selected welding scheme;

[0010] (4) Ultrasonic testing shall be performed on the two layers of welds of the uniform gas structure. There shall be no penetration defects between the three gas channels and between them and the outside of the product.

[0011] (5) Perform helium testing on the welded blank of the uniform gas structure, evacuate the three gas channels respectively, and pass helium through other gas channels and around the product.

[0012] (6) Remove the excess material from the lower plate to expose the vent holes, and during the processing, introduce clean compressed air from the vent hole side; then determine the processing reference based on the shape of the blank after welding of the uniform gas structure, use a projector to detect the vent position data, compare it with the theoretical position data of the drawing, and adjust the processing reference of the uniform gas structure after welding again.

[0013] (7) The gas uniform structure blank after welding is precision machined according to the adjusted processing benchmark, and finally the multi-layer complex flow channel aluminum alloy gas uniform structure product is obtained.

[0014] Furthermore, the multi-layered complex flow channel aluminum alloy gas distribution structure includes an upper plate, a middle plate, and a lower plate, which are connected by diffusion welding.

[0015] The upper plate has several air inlets, through which process gases enter the structure.

[0016] The front and back sides of the middle plate are respectively distributed with radial and annular flow channels. There are several through holes in the flow channels to connect the front and back sides of the middle plate. The process gas is divided into three gas channels through the flow channel on the front side of the middle plate, and then enters the back side of the middle plate through the through holes in the flow channel, and is further evenly dispersed through the annular flow channel on the back side of the middle plate.

[0017] The lower plate has several tiny vent holes, through which process gas is evenly injected onto the parts below the gas distribution structure.

[0018] Furthermore, the process gas is divided into three gas channels through the front flow channel of the middle plate, and after entering the back of the middle plate, it forms three regions: outer ring, middle ring and inner ring, which are used to independently control the gas flow rate of each region.

[0019] Furthermore, when processing the pre-welding blanks of the upper, middle, and lower layers, ensure that the parallelism and flatness of the welding surfaces are no greater than 0.05mm and the roughness is better than 0.8um.

[0020] Furthermore, the ratio of the welding areas refers to dividing the larger value by the smaller value.

[0021] Furthermore, when the ratio of the welding areas is greater than 1.3, a multi-stage welding scheme is selected. First, diffusion welding is performed on the two layers with larger welding areas. Then, the two layers after welding are subjected to gas quenching. After gas quenching, the two layers are processed again to ensure that the parallelism and flatness of the welding surfaces are no greater than 0.05mm and the roughness is better than 0.8um. ​​Then, the two layers after gas quenching are diffusion welded to another layer.

[0022] The parameters for both welding operations were 560℃ for 90 minutes, welding pressure of 4MPa, and welding area based on actual conditions. Stainless steel limit blocks were placed evenly along the circumference of the gas equalization structure during welding, with intervals of 100-120mm. The thickness of the stainless steel limit blocks was 0.2mm less than the thickness of the welded parts, and the diameter was 1 / 10 of the diameter of the gas equalization structure.

[0023] Furthermore, when the ratio of the welding areas is less than or equal to 1.3, a single welding scheme is selected, and the upper, middle and lower plates are simultaneously subjected to diffusion welding. The diffusion welding parameters are 560℃ for 90 minutes, welding pressure of 4MPa, and the welding area is based on the larger welding area between the upper and middle plates and between the middle and lower plates. The thickness of the stainless steel limiting block is 0.3mm less than the thickness of the welded parts, and the diameter is 1 / 10 of the diameter of the gas equalization structure. They are placed evenly along the circumference of the gas equalization structure at intervals of 100-120mm.

[0024] Furthermore, ultrasonic testing was performed on the two layers of welds in the uniform gas structure, and the brazing rate was not less than 90%.

[0025] Furthermore, when performing helium testing on the weld blank of the uniform gas structure, the weld leakage rate should be better than 1.0 × 10⁻⁶. - 10 Pa.m 3 / s.

[0026] Furthermore, helium testing is performed on the welded blank of the uniform gas structure. Vacuum is evacuated from the three gas channels, and helium is introduced into the other gas channels and around the product. Specifically, when one gas channel is evacuated, helium is introduced into the other two gas channels. Helium testing is performed in this alternating manner.

[0027] Furthermore, the post-weld machining datum of the gas distribution structure was adjusted to ensure that the actual position of all vent holes deviates from the theoretical position on the drawing by less than 0.2mm.

[0028] The advantages of this invention compared to the prior art are:

[0029] (1) For multi-layer diffusion welded structures, when the areas of two welds differ significantly, diffusion welding is directly applied to the multi-layer structure. The weld with a smaller weld area will result in excessive welding deformation due to the higher pressure per unit area, while the weld with a larger weld area will result in a decrease in welding quality due to the lower pressure per unit area.

[0030] Therefore, for diffusion welded structures with large differences in weld area, the present invention adopts a multi-stage welding scheme, and after the first welding, the welded parts are subjected to gas quenching treatment to improve the strength of the parts, thereby reducing the welding deformation during the second welding. This ensures the welding quality of the multi-layer diffusion welded structure and reduces welding deformation.

[0031] For diffusion welded structures with small differences in weld area, a single-welding scheme is adopted. By reducing the number of welding operations and using limiting blocks to restrict the deformation of the welded parts, the welding quality of multi-layer diffusion welded structures is guaranteed, while welding deformation is reduced.

[0032] (2) The diameter of the air outlet holes on the lower surface of the multi-layer complex flow channel aluminum alloy gas uniform structure is generally 0.5 to 2.5 mm, and the number is 300 to 1000.

[0033] If the vent holes are properly machined before welding, it is very difficult to seal such a large number of small holes when performing helium testing on the weld. If some small holes are not sealed properly, it will affect the helium testing results.

[0034] If the vent holes are opened by post-weld machining, it will be impossible to avoid machining debris entering the gas distribution structure. Once the machining debris enters the internal flow channel, it will be difficult to remove it due to the complex structure of the flow channel.

[0035] Therefore, this invention employs a machining method where the vent hole is left unmachined during pre-welding processing, and becomes a blind hole after welding, ensuring the vent hole's sealing during helium testing. After helium testing, the excess material in the vent hole is removed to expose it. During the machining process, clean compressed air at 0.6–0.9 MPa is introduced from the inlet side, creating an outward-spraying airflow from the vent hole to prevent machining debris from entering. This ensures the smooth completion of helium testing and prevents machining debris from entering the flow channel.

[0036] (3) Since diffusion welding is carried out under high temperature and high pressure, the gas equalization structure undergoes overall welding deformation after welding. On the one hand, the pre-weld processing reference shifts. If the gas equalization structure is still finely processed after welding according to the general processing method, the position of the gas outlet on the lower surface of the gas equalization structure will be greatly deviated, resulting in uneven gas output from the gas equalization structure. On the other hand, the position of the gas outlet will also shift to a certain extent due to welding deformation.

[0037] Therefore, this invention adopts a method of secondary adjustment of the post-weld processing reference. First, the processing reference is determined by the shape of the blank after welding of the gas uniform structure. Then, the post-weld positional data of the pores is detected by a projector and compared with the theoretical positional data of the drawing. The post-weld processing reference of the gas uniform structure is adjusted a second time. At the same time, the method in technical advantage 1 is adopted to reduce the welding deformation of the gas uniform structure, so that the actual positional deviation of all pores from the theoretical positional deviation of the drawing is less than 0.2mm. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the upper layer plate;

[0039] Figure 2 This is a front view of the middle layer plate;

[0040] Figure 3 This is a schematic diagram of the reverse side of the middle layer plate;

[0041] Figure 4 This is a schematic diagram of the lower layer plate;

[0042] Figure 5 This is a schematic diagram of the air outlet machining process. Detailed Implementation

[0043] The present invention will be further described in detail below with reference to specific embodiments.

[0044] This invention relates to a low-deformation diffusion welding method for a multi-layer complex flow channel aluminum alloy gas uniform structure, wherein the multi-layer complex flow channel aluminum alloy gas uniform structure includes an upper plate, a middle plate, and a lower plate, and the upper plate, middle plate, and lower plate are connected by diffusion welding.

[0045] like Figure 1 As shown, the upper plate has several air inlets, through which process gases enter the structure.

[0046] like Figure 2 and Figure 3 As shown, radial and annular flow channels are distributed on the front and back sides of the middle plate, respectively. Several through holes in the flow channels connect the front and back sides of the middle plate. The process gas is divided into three gas channels through the flow channel on the front side of the middle plate, and then enters the back side of the middle plate through the through holes in the flow channel. It is further evenly dispersed through the annular flow channel on the back side of the middle plate.

[0047] like Figure 4 As shown, the lower plate has several tiny air outlets, through which process gas is evenly injected onto the parts below the gas distribution structure.

[0048] The process gas is divided into three gas channels through the front flow channel of the middle plate. After entering the back of the middle plate, it forms three regions: outer ring, middle ring and inner ring, which are used to independently control the gas flow rate of each region.

[0049] by Figure 1 , Figure 2 and Figure 3 For example, the upper plate has five through holes in its central area. The central through hole corresponds to a shorter, straight air passage in the center of the middle plate, with ventilation holes at both ends connecting to the innermost annular air passage on the back of the middle plate. The two through holes to the left and right of the central through hole in the upper plate correspond to the left and right radial flow channels on the middle plate, respectively, allowing air to enter the annular flow channel in the middle ring area on the reverse side of the middle plate, for example, rings 2 to 4. The two through holes above and below the central through hole in the upper plate correspond to the upper and lower radial flow channels on the middle plate, respectively, allowing air to enter the annular flow channel in the outer ring area on the reverse side of the middle plate, for example, rings 5 ​​to 7.

[0050] The diffusion welding method includes the following steps:

[0051] (1) Process the pre-welding blanks of the upper, middle, and lower layers according to the product structure, ensuring that the parallelism and flatness of the welding surfaces are no greater than 0.05mm and the roughness is better than 0.8um. ​​The vent holes in the lower layer are blind holes, leaving a margin that is not machined through. Figure 5 As shown.

[0052] (2) Pickling is performed on the pre-welding blanks of the upper, middle and lower layers to ensure that the welding surfaces are clean and free of oil.

[0053] (3) Based on the ratio of the welding area between the upper and middle layers and between the middle and lower layers (comparing the larger value to the smaller value), select either a multi-stage welding scheme or a single-stage welding scheme and carry out the welding.

[0054] For diffusion weld structures with significant differences in weld area, a multi-stage welding approach is adopted. After the first weld, the welded parts are gas-quenched to improve their strength, thereby reducing welding deformation during the second weld. This approach ensures both the welding quality of the multi-layer diffusion weld structure and reduces welding deformation. For diffusion weld structures with minor differences in weld area, a single-stage welding approach is used. By reducing the number of welds and simultaneously using limiting blocks to restrict the deformation of the welded parts, this approach also ensures the welding quality of the multi-layer diffusion weld structure and reduces welding deformation.

[0055] The specific welding scheme selection is as follows:

[0056] When the ratio of the welding areas is greater than 1.3, a staged welding scheme is selected. First, diffusion welding is performed on the two plates with the larger welding area. Then, the welded two plates are gas quenched. After gas quenching, the two plates are processed again to ensure that the parallelism and flatness of the welding surfaces are no greater than 0.05mm and the roughness is better than 0.8um. ​​Then, the gas-quenched two plates are diffusion welded to another plate. The parameters for both welding processes are 560℃ for 90min, welding pressure 4MPa, and welding area based on actual conditions. The thickness of the stainless steel limiting block is 0.2mm less than the thickness of the welded part, and its diameter is 1 / 10 of the diameter of the gas equalization structure. They are placed evenly along the circumference of the gas equalization structure at intervals of 100-120mm.

[0057] When the ratio of the welding area is less than or equal to 1.3, a single welding scheme is selected, and the upper plate, middle plate and lower plate are simultaneously subjected to diffusion welding. The diffusion welding parameters are 560℃ for 90 minutes, welding pressure of 4MPa, and the welding area is based on the larger welding area between the upper plate and the middle plate and between the middle plate and the lower plate. The thickness of the stainless steel limiting block is 0.3mm less than the thickness of the welded part, and the diameter is 1 / 10 of the diameter of the gas equalization structure. They are placed evenly along the circumference of the gas equalization structure at intervals of 100-120mm.

[0058] (4) Ultrasonic testing shall be performed on the two layers of welds of the uniform gas structure. The brazing rate shall not be less than 90%. There shall be no penetration defects between the three gas channels and between them and the outside of the product.

[0059] (5) Perform helium testing on the welded blank of the uniform gas structure. Vacuum the three gas paths separately, and purge the other gas paths and the area around the product with helium. The weld leakage rate should be better than 1.0 × 10⁻⁶. -10 Pa.m 3 / s.

[0060] When one of the gas channels is evacuated, helium is introduced into the other two gas channels, and helium detection is performed in rotation.

[0061] (6) Remove the excess material from the lower plate to expose the vent holes. During the processing, clean compressed air is introduced from the side of the air inlet hole. Then, the processing reference is determined by the shape of the blank after welding of the uniform air structure. The positional data of the vent holes is detected by a projector and compared with the theoretical positional data of the drawing. The processing reference of the uniform air structure after welding is adjusted again so that the actual positional value of all vent holes deviates from the theoretical positional value of the drawing by less than 0.2mm.

[0062] (7) The gas uniform structure blank after welding is precision machined according to the adjusted processing benchmark, and finally the multi-layer complex flow channel aluminum alloy gas uniform structure product is obtained.

[0063] In this invention, the vent hole is processed by leaving a margin before welding and making it a blind hole after welding, thus ensuring the sealing of the vent hole during helium testing. After the helium test is completed, the margin of the vent hole is removed to expose it. During the processing, clean compressed air at 0.6 to 0.9 MPa is introduced from the air inlet side to create an outward airflow from the vent hole, preventing the entry of processing debris. This ensures the smooth completion of the helium test and also prevents processing debris from entering the flow channel.

[0064] Meanwhile, the present invention adopts a method of secondary adjustment of the post-weld processing benchmark. First, the processing benchmark is determined by the shape of the blank after welding of the gas uniform structure. Then, the post-weld positional data of the pores is detected by a projector and compared with the theoretical positional data of the drawing to make a secondary adjustment to the post-weld processing benchmark of the gas uniform structure. At the same time, the method in claim 2 is used to reduce the welding deformation of the gas uniform structure, so that the actual positional deviation of all pores from the theoretical positional deviation of the drawing is less than 0.2mm.

[0065] Example 1:

[0066] Pre-welding blanks of the upper, middle, and lower layers are processed according to the product structure, ensuring that the parallelism and flatness of the welding surfaces are no greater than 0.05mm and the roughness is better than 0.8um. ​​The vent holes of the lower layer are blind holes, leaving a margin for machining without opening them. The pre-welding blanks of the upper, middle, and lower layers are pickled to ensure that the welding surfaces are clean and free of oil.

[0067] Since the ratio of the welding area is greater than 1.3, diffusion welding is first performed on the two plates with the larger welding area. Then, the welded two plates are gas quenched. After gas quenching, the two plates are processed a second time to ensure that the parallelism and flatness of the welding surface are no greater than 0.05 mm and the roughness is better than 0.8 μm. Then, the gas-quenched two plates are diffusion welded to another plate. The parameters for both welding processes are 560℃ for 90 min, welding pressure 4 MPa, and welding area based on actual conditions. The thickness of the stainless steel limiting block is 0.2 mm less than the thickness of the welded part, and its diameter is 1 / 10 of the diameter of the gas equalization structure. They are evenly placed along the circumference of the gas equalization structure at intervals of 100-120 mm.

[0068] Ultrasonic testing should be performed on the two layers of welds in the uniform gas structure. The brazing rate should be no less than 90%, and there should be no penetrating defects between the three gas channels or between the gas channels and the outer side of the product. Helium testing should be performed on the welded blank of the uniform gas structure. Vacuum should be evacuated from each of the three gas channels, and helium should be introduced into the other gas channels and around the product. The weld leakage rate should be better than 1.0 × 10⁻⁶. -10 Pa.m 3 / s.

[0069] Remove the excess material from the lower plate to expose the vent holes. During the processing, clean compressed air is introduced from the air inlet side. Then, the processing datum is determined by the shape of the blank after welding of the uniform air structure. The positional data of the vent holes is detected by a projector and compared with the theoretical positional data of the drawing. The processing datum of the uniform air structure after welding is adjusted again so that the actual positional accuracy of all vent holes deviates from the theoretical positional accuracy of the drawing by less than 0.2mm.

[0070] The post-weld blank of the gas uniform structure is precision machined according to the adjusted processing benchmark, and finally a multi-layer complex flow channel aluminum alloy gas uniform structure product is obtained.

[0071] Example 2:

[0072] Pre-welding blanks of the upper, middle, and lower layers are processed according to the product structure, ensuring that the parallelism and flatness of the welding surfaces are no greater than 0.05mm and the roughness is better than 0.8um. ​​The vent holes of the lower layer are blind holes, leaving a margin for machining without opening them. The pre-welding blanks of the upper, middle, and lower layers are pickled to ensure that the welding surfaces are clean and free of oil.

[0073] Since the ratio of the welding area is less than or equal to 1.3, the upper, middle and lower plates are simultaneously subjected to diffusion welding. The diffusion welding parameters are 560℃ for 90 minutes, welding pressure of 4MPa, and the welding area is based on the larger welding area between the upper and middle plates and between the middle and lower plates. The thickness of the stainless steel limiting block is 0.3mm less than the thickness of the welded parts, and the diameter is 1 / 10 of the diameter of the gas equalization structure. They are evenly placed along the circumference of the gas equalization structure at intervals of 100-120mm.

[0074] Ultrasonic testing should be performed on the two layers of welds in the uniform gas structure. The brazing rate should be no less than 90%, and there should be no penetrating defects between the three gas channels or between the gas channels and the outer side of the product. Helium testing should be performed on the welded blank of the uniform gas structure. Vacuum should be evacuated from each of the three gas channels, and helium should be introduced into the other gas channels and around the product. The weld leakage rate should be better than 1.0 × 10⁻⁶. -10 Pa.m 3 / s.

[0075] Remove the excess material from the lower plate to expose the vent holes, such as... Figure 5 As shown, during the processing, clean compressed air is introduced from the air inlet side. Then, the processing datum is determined by the shape of the blank after welding of the uniform air structure. The positional data of the air holes is detected by a projector and compared with the theoretical positional data of the drawing. The processing datum of the uniform air structure after welding is adjusted again so that the actual positional value of all air holes deviates from the theoretical positional value of the drawing by less than 0.2mm.

[0076] The post-weld blank of the gas uniform structure is precision machined according to the adjusted processing benchmark, and finally a multi-layer complex flow channel aluminum alloy gas uniform structure product is obtained.

[0077] The parts of this invention not described in detail are well-known to those skilled in the art.

Claims

1. A low-deformation diffusion welding method for multi-layer complex flow channel aluminum alloy uniform gas structure, characterized in that... include: (1) Process the pre-welding blanks of the upper plate, middle plate and lower plate according to the product structure. The air vent of the lower plate is a blind hole, and the allowance is left unprocessed. (2) Pickling is performed on the pre-welding blanks of the upper, middle and lower layers to ensure that the welding surfaces are clean and free of oil. (3) Based on the ratio of the welding area between the upper and middle layers and between the middle and lower layers, select either a multi-stage welding scheme or a single-stage welding scheme, and perform welding according to the selected welding scheme; When the ratio of the welding areas is greater than 1.3, a staged welding scheme is selected. First, diffusion welding is performed on the two layers with the larger welding area. Then, the welded two layers are subjected to gas quenching. After gas quenching, the two layers are processed again to ensure that the parallelism and flatness of the welding surfaces are no greater than 0.05 mm and the roughness is better than 0.8 μm. Then, the gas-quenched two layers are diffusion welded to another layer. The parameters for both welding processes are 560℃ for 90 min, welding pressure of 4 MPa, and the welding area is subject to actual conditions. When the ratio of the welded areas is less than or equal to 1.3, a single-weld method should be selected. (4) Ultrasonic testing shall be performed on the two layers of welds of the uniform gas structure. There shall be no penetration defects between the three gas channels and between them and the outside of the product. (5) Perform helium testing on the welded blank of the uniform gas structure, evacuate the three gas channels respectively, and pass helium through other gas channels and around the product. (6) Remove the excess material from the lower plate to expose the vent holes, and during the processing, introduce clean compressed air from the vent hole side; then determine the processing reference based on the shape of the blank after welding of the uniform gas structure, use a projector to detect the vent position data, compare it with the theoretical position data of the drawing, and adjust the processing reference of the uniform gas structure after welding again. (7) The gas uniform structure blank after welding is precision machined according to the adjusted processing benchmark, and finally the multi-layer complex flow channel aluminum alloy gas uniform structure product is obtained.

2. The low-deformation diffusion welding method for a multi-layer complex flow channel aluminum alloy uniform gas structure according to claim 1, characterized in that: The multi-layered complex flow channel aluminum alloy gas distribution structure includes an upper plate, a middle plate, and a lower plate, which are connected by diffusion welding. The upper plate has several air inlets, through which process gases enter the structure. The front and back sides of the middle plate are respectively distributed with radial and annular flow channels. There are several through holes in the flow channels to connect the front and back sides of the middle plate. The process gas is divided into three gas channels through the flow channel on the front side of the middle plate, and then enters the back side of the middle plate through the through holes in the flow channel, and is further evenly dispersed through the annular flow channel on the back side of the middle plate. The lower plate has several tiny vent holes, through which process gas is evenly injected onto the parts below the gas distribution structure.

3. The low-deformation diffusion welding method for a multi-layer complex flow channel aluminum alloy uniform gas structure according to claim 2, characterized in that: The process gas is divided into three gas channels through the front flow channel of the middle plate. After entering the back of the middle plate, it forms three regions: outer ring, middle ring and inner ring, which are used to independently control the gas flow rate of each region.

4. The low-deformation diffusion welding method for a multi-layer complex flow channel aluminum alloy uniform gas structure according to claim 2, characterized in that: When processing the pre-welding blanks of the upper, middle, and lower layers, ensure that the parallelism and flatness of the welding surfaces are no greater than 0.05mm and the roughness is better than 0.8um.

5. The low-deformation diffusion welding method for a multi-layer complex flow channel aluminum alloy uniform gas structure according to claim 1, characterized in that: The ratio of the welding areas refers to dividing the larger value by the smaller value.

6. The low-deformation diffusion welding method for a multi-layer complex flow channel aluminum alloy uniform gas structure according to claim 1, characterized in that: When performing multi-stage welding, stainless steel limit blocks are set up during welding and placed evenly along the circumference of the gas equalization structure at intervals of 100-120mm. The thickness of the stainless steel limit blocks is 0.2mm less than the thickness of the welded parts, and the diameter is 1 / 10 of the diameter of the gas equalization structure.

7. The low-deformation diffusion welding method for a multi-layer complex flow channel aluminum alloy uniform gas structure according to claim 1, characterized in that: When selecting the single-pass welding scheme, the upper, middle, and lower plates are simultaneously subjected to diffusion welding. The diffusion welding parameters are 560℃ for 90 minutes, welding pressure of 4MPa, and the welding area is based on the larger welding area between the upper and middle plates and between the middle and lower plates. The thickness of the stainless steel limiting blocks is 0.3mm less than the thickness of the welded parts, and the diameter is 1 / 10 of the diameter of the gas equalization structure. They are placed evenly along the circumference of the gas equalization structure at intervals of 100-120mm.

8. The low-deformation diffusion welding method for a multi-layer complex flow channel aluminum alloy uniform gas structure according to claim 1, characterized in that: Ultrasonic testing was performed on the two layers of welds in the uniform gas structure, and the brazing rate was not less than 90%.

9. The low-deformation diffusion welding method for a multi-layer complex flow channel aluminum alloy uniform gas structure according to claim 1, characterized in that: When performing helium testing on the weld blank of a uniform gas structure, the weld leakage rate should be better than 1.0 × 10⁻⁶. -10 Pa.m 3 / s.

10. The low-deformation diffusion welding method for a multi-layer complex flow channel aluminum alloy uniform gas structure according to claim 1, characterized in that: Helium testing is performed on the welded blank of the uniform gas structure. Vacuum is evacuated in three gas channels, and helium is introduced into other gas channels and around the product. Specifically, when one gas channel is evacuated, helium is introduced into the other two gas channels. Helium testing is performed in this alternating manner.

11. The low-deformation diffusion welding method for a multi-layer complex flow channel aluminum alloy uniform gas structure according to claim 1, characterized in that: Adjust the post-weld machining datum of the gas distribution structure to ensure that the actual position of all vent holes deviates from the theoretical position on the drawing by less than 0.2mm.

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