A continuous diffusion bonding apparatus

Abstract

The utility model relates to diffusion welding technical field especially relates to a continuous diffusion welding equipment. Including: the feeding unit, preheating unit, welding unit, cooling unit and blanking unit that are sequentially communicated along the welding piece conveying direction are set, are provided with the vacuumizing unit between every adjacent unit, the inside of every unit all is installed with the conveying unit for the butt joint of welding piece and intercommunication, the material conveying direction of feeding unit is perpendicular with the material conveying direction of preheating unit, welding unit, cooling unit and blanking unit respectively setting, preheating unit, welding unit and cooling unit same side setting. The utility model provides a continuous diffusion welding equipment with welding quality is good, the finished product rate is high, welding efficiency is high and the advantages such as wide application range.

Description

Technical Field

[0001] This utility model relates to the field of diffusion welding technology, and in particular to a continuous diffusion welding device. Background Technology

[0002] Diffusion welding is a welding method in which two workpieces to be welded are pressed tightly together and heated in a vacuum or protective atmosphere furnace. This causes microscopic plastic deformation in the tiny unevenness of the two welding surfaces, achieving close contact. During subsequent heating and holding, atoms diffuse into each other to form a metallurgical bond. This type of diffusion welding is usually called solid-phase diffusion.

[0003] Chinese patent CN218694879U discloses a soft-joint diffusion welding device suitable for automated production lines, including a feeding and calibration module, which includes a calibration and clamping component and a feeding three-axis robot; a diffusion welding module for diffusion welding of soft joints; and a feeding and cooling module, which includes a feeding three-axis robot and a cooling and receiving component. This invention calibrates and clamps the material using the calibration and clamping component, moves the material using the feeding and receiving three-axis robot, performs diffusion welding in conjunction with the diffusion welding machine, and finally cools the welded material while it is being received through a cooling channel and receiving box. This achieves automation while adapting well to moldless production methods, highly meeting the requirements of diffusion welding, eliminating the need for manual intervention, avoiding the inaccuracies and safety issues that may arise from manual operation, and significantly improving production efficiency.

[0004] However, this technical solution directly welds the workpiece without a preheating process. The sudden temperature rise can cause the oxide layer on the surface of the workpiece to not decompose completely or the pollutants to not volatilize sufficiently, which hinders the diffusion of atoms across the interface and forms unwelded areas (such as micropores, cold welds, etc.), resulting in poor welding quality. Utility Model Content

[0005] The purpose of this invention is to address the shortcomings of existing technologies by providing a continuous diffusion welding device. By adding a preheating unit in the process preceding the welding unit, the oxide layer on the surface of the weldment can be fully decomposed or contaminants can be fully volatilized to activate the surface of the weldment, thereby increasing the atomic migration rate, avoiding local incomplete welding, and ensuring welding quality.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A continuous diffusion welding device includes: a feeding unit, a preheating unit, a welding unit, a cooling unit, and a discharging unit arranged sequentially along the workpiece conveying direction. A vacuuming unit is provided between each adjacent unit. Each unit has an interconnected conveying unit for receiving the workpiece. The material conveying direction of the feeding unit is perpendicular to the material conveying direction of the preheating unit, the welding unit, the cooling unit, and the discharging unit, respectively. The preheating unit, the welding unit, and the cooling unit are arranged on the same side.

[0008] Preferably, the preheating unit includes: a plurality of heating zones with progressively increasing temperatures and a plurality of pressure regulating mechanisms disposed within the heating zones.

[0009] Preferably, the heating zone includes: a heating furnace for accommodating the weldment and a plurality of heating units evenly distributed within the heating furnace, wherein the weldment is placed on the heating unit.

[0010] Preferably, the pressure regulating mechanism includes an external interface and an airflow channel disposed at the end of the external interface, the airflow channel being connected to a cavity inside the preheating unit.

[0011] Preferably, the temperature range of the heating zone is 800℃-1200℃.

[0012] Preferably, the welding unit includes: a plurality of first lifting components, a welding device correspondingly disposed at the bottom of the first lifting components, and a receiving plate disposed below the welding device for receiving the weldment.

[0013] Preferably, the cooling unit includes: a second lifting member and a water-cooling member disposed on the second lifting member.

[0014] Preferably, a discharge mechanism is provided on one side of the cooling unit.

[0015] Preferably, the discharge mechanism includes: a receiving pipe disposed on one side of the conveying unit, a first switch disposed at one end of the receiving pipe, and a second switch disposed at the other end of the receiving pipe.

[0016] Preferably, the vacuum unit includes: a sealing cover disposed on the conveying unit, lifting doors disposed at both ends of the sealing cover, and a vacuum device disposed on the sealing cover.

[0017] Preferably, the feeding unit, preheating unit, welding unit, cooling unit, and unloading unit are all equipped with a horizontal pushing mechanism on the opposite side of their discharge ports for pushing the weldment to the next unit.

[0018] The beneficial effects of this utility model are as follows:

[0019] (1) This utility model forms an automated production line welding process by combining multiple processes. The conveying unit adopts an ultra-precise feeding mechanism, equipped with a high-precision linear motor to drive the feeding track, and combined with advanced optical sensors to realize real-time monitoring of material position. The positioning accuracy is high, ensuring that the weldment is always kept in the best welding position during continuous feeding. The weldment can complete all processes in one clamping, with short cycle time and high efficiency. In addition, the preheating unit is combined to activate the surface of the weldment, further improving the welding quality.

[0020] (2) This utility model divides the preheating unit into several heating zones with progressively increasing temperatures, and is equipped with several pressure regulating mechanisms. Each heating zone is controlled by a high-precision temperature sensor (accuracy up to ±0.5℃) and an intelligent temperature controller to achieve complex temperature curve control, ensuring that the temperature uniformity deviation of the welding area is within ±2℃, meeting the strict requirements of different materials for welding temperature, and has a wide range of applications.

[0021] (3) This utility model introduces a protective gas, such as high-purity argon (purity ≥99.999%), into the welding area. The gas enters the cavity through the airflow channel and forms a uniform and stable gas curtain through a specially designed gas nozzle, which isolates the welding area from the outside air. The gas flow rate can be precisely adjusted in the range of 5-20L / min by the intelligent control system, which effectively protects the welding area and improves the quality of the weld and the yield.

[0022] In summary, this utility model has the advantages of good welding quality, high yield, high welding efficiency and wide applicability. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0024] Figure 2 This is a cross-sectional view of the present invention taken from the welding unit side;

[0025] Figure 3 for Figure 2 Enlarged view of point A;

[0026] Figure 4 for Figure 2 Enlarged view of point B;

[0027] Figure 5 This is a cross-sectional view of the present invention taken from the side of the feeding unit. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0030] Example

[0031] like Figures 1-5 As shown, this embodiment provides a continuous diffusion welding equipment, including: a feeding unit 1, a preheating unit 2, a welding unit 3, a cooling unit 4, and a discharging unit 5 arranged sequentially along the conveying direction of the workpiece 100. The workpiece 100 can complete all processes in one clamping, with short cycle time and high efficiency. A vacuum unit 6 is provided between each adjacent unit, which ensures a high vacuum in the welding area while allowing normal pressure operation in the loading and unloading areas, reducing the overall vacuuming time. Each unit is equipped with a conveying unit 7 that is interconnected and used to receive the workpiece 100. The material conveying direction of the feeding unit 1 is perpendicular to the material conveying direction of the preheating unit 2, the welding unit 3, the cooling unit 4, and the discharging unit 5, respectively. The preheating unit 2, the welding unit 3, and the cooling unit 4 are arranged on the same side, making the equipment "L" or "U" shaped, which significantly shortens the length of the cleanroom and saves cleanroom area.

[0032] The conveying unit 7 typically employs an ultra-precision feeding mechanism, equipped with a high-precision linear motor driving the feeding track, and combined with advanced optical sensors to achieve real-time monitoring of the material position, with a positioning accuracy of up to ±0.05mm. This ensures that the weldment 100 remains in the optimal welding position during continuous feeding, providing a solid foundation for high-quality welding. The section of the feeding track between the loading unit 1 and the unloading unit 5 is the initial placement position for the weldment 100. Manual loading and unloading are generally used here, but automatic loading and unloading can also be performed using robotic arms or other mechanisms.

[0033] Meanwhile, the preheating unit 2 includes several heating zones 21 with progressively increasing temperatures and several pressure regulating mechanisms 22 disposed inside the heating zones 21. Each heating zone 21 is controlled by a high-precision temperature sensor (accuracy up to ±0.5℃) and an intelligent temperature controller to achieve complex temperature curve control, ensuring that the temperature uniformity deviation of the welding area is within ±2℃, and meeting the strict requirements of different materials for welding temperature.

[0034] In this embodiment, the pressure regulating mechanism 22 can apply micro-pressure to the weldment 100 during the preheating stage, so that the contact surfaces can be tightly fitted in advance, shortening the subsequent high temperature diffusion time. Generally, a hydraulic or pneumatic servo system is used for dynamic pressure regulation, and the pressure control accuracy can reach ±0.3MPa, so as to adapt to different stages in the welding process and optimize the welding quality.

[0035] In this embodiment, the heating zone 21 includes a heating furnace 211 for accommodating the weldment 100 and a plurality of heating units 212 evenly distributed in the heating furnace 211, and the weldment 100 is placed on the heating unit 212.

[0036] In this embodiment, the heating unit 212 is generally made of special graphite material and high-temperature alloy material. Due to its high purity, high strength, high thermal conductivity and good high temperature resistance, special graphite can withstand temperatures exceeding 2000°C, ensuring uniform temperature distribution of the mold and avoiding local overheating or undercooling that could affect welding quality. At the same time, its high strength ensures that the mold is not easily deformed under high pressure, extending its service life. The excellent high-temperature strength, oxidation resistance and thermal fatigue resistance of high-temperature alloys make them particularly suitable for molds with complex shapes and high precision requirements. The application of high-temperature alloys helps to improve the stability of the welding process and the durability of the mold.

[0037] In this embodiment, the pressure regulating mechanism 22 includes an external interface 221 and an airflow channel 222 disposed at the end of the external interface 221. The airflow channel 222 is connected to the cavity inside the preheating unit 2. The clamping force on the weldment 100 can be steplessly changed by adjusting the airflow pressure. There is no need for mechanical springs or hydraulic cylinders to extend into the high-temperature zone. The structure is simple and the heat-affected zone is small. In addition, the airflow channel 222 is directly connected to the cavity of the preheating unit 2. When the vacuum unit 6 is used, the residual gas is extracted simultaneously to avoid oxidation.

[0038] In this embodiment, high-purity argon gas (purity ≥99.999%) is generally used as the protective gas. It enters the cavity through the airflow channel 222 and forms a uniform and stable gas curtain through a specially designed gas nozzle, which isolates the welding area from the outside air. The gas flow rate can be precisely adjusted within the range of 5-20L / min by the intelligent control system, which effectively protects the welding area and improves the quality of the weld and the yield.

[0039] In this embodiment, the pressure range of the pressure regulating mechanism 22 is 5MPa-50MPa. The welding pressure is crucial for promoting close contact between the surfaces of the workpiece 100, accelerating atomic diffusion, and preventing defects such as pores. The pressure needs to take into account factors such as material properties, workpiece 100 size, and equipment capabilities. The specific pressure value for continuous diffusion welding needs to be adjusted according to product requirements.

[0040] In this embodiment, the temperature range of the heating zone 21 is 800℃-1200℃, which avoids thermal stress cracks in the weldment 100 due to sudden heating and improves the yield.

[0041] In this embodiment, in order to obtain the best welding effect, the optimal welding temperature needs to be accurately determined through thermal simulation experiments and numerical simulation analysis based on the material composition, structure and performance requirements of the weldment 100. For example, high-performance copper-based heat dissipation materials may require the welding temperature to be precisely controlled between 1050 and 1100°C.

[0042] In this embodiment, the welding unit 3 includes: a plurality of first lifting members 31, a welding device 32 correspondingly disposed at the bottom of the first lifting members 31, and a receiving plate 33 disposed below the welding device 32 for receiving the weldment 100. The first lifting members 31 drive the welding device 32 to press down, and the set pressure can be reached within a few seconds, shortening the welding cycle; the welding device 32 is generally preferably a welding machine.

[0043] In this embodiment, the cooling unit 4 includes a second lifting member 41 and a water-cooling member 42 disposed on the second lifting member 41. The second lifting member 41 presses the water-cooling member 42 against the weldment 100, and fast or slow cooling can be achieved by adjusting the cooling water flow rate.

[0044] In this embodiment, the water-cooling component 42 is preferably an installation plate with multiple condensate pipes built in. It can be pulled out as a whole for maintenance without disassembling the pipes, making it simple to operate and convenient to use. The size of the installation plate is adapted to the size of the weldment 100, ensuring that the weldment 100 can be cooled evenly and with high cooling efficiency.

[0045] In this embodiment, a discharge mechanism 8 is provided on one side of the cooling unit 4. The discharge mechanism 8 includes: a receiving pipe 81 provided on one side of the conveying unit 7, a first switch 82 provided at one end of the receiving pipe 81, and a second switch 83 provided at the other end of the receiving pipe 81, forming a vacuum lock structure. When the weldment 100 is discharged, the vacuum state of the welding area is not destroyed, realizing continuous production. The entire process is transported through pipelines, avoiding manual handling of the high-temperature weldment 100 and improving safety.

[0046] In this embodiment, the vacuum unit 6 includes: a sealing cover 61 disposed on the conveying unit 7, lifting doors 62 disposed at both ends of the sealing cover 61, and a vacuum device 63 disposed on the sealing cover 61. Each unit is independently sealed, and different vacuum levels can be set for different processes. The vacuum device 63 is then used to perform a vacuum operation on the inside of the sealing cover 61, so that the inside of the sealing cover 61 is in a vacuum or oxygen-free state, thus preventing oxidation of the weldment 100. The vacuum device 63 generally uses a combination of a mechanical pump and a molecular pump.

[0047] In this embodiment, the feeding unit 1, preheating unit 2, welding unit 3, cooling unit 4, and unloading unit 5 are all equipped with a horizontal pushing mechanism 9 on the opposite side of their discharge ports for pushing the weldment 100 to the next unit. The horizontal pushing mechanism 9 is generally a cylinder, and its operation is uniformly controlled by the main control PLC to ensure that the workpiece moves in a consistent rhythm between units, avoid blockage, and the push rod at the end of the cylinder only needs to be pushed once to reset, simplifying the mechanical structure and improving reliability.

[0048] In this embodiment, the principle of continuous diffusion soldering technology is generally divided into three stages: the close contact stage, the atomic diffusion stage, and the joint formation and improvement stage. The close contact stage is the starting step of continuous diffusion soldering technology. In this stage, the workpiece 100 (a chip heat sink assembly in this embodiment) enters the soldering area during continuous transport and is subjected to a certain pressure. The pressure causes the microscopic protrusions on the surface of the workpiece 100 to undergo plastic deformation, thereby increasing the actual contact area until the distance of interatomic interaction is reached, which is approximately (1 - 5) × 10⁻ 8 cm, laying the foundation for subsequent atomic diffusion.

[0049] In this embodiment, during the atomic diffusion stage, the atoms of the weldment 100 are continuously heated to a suitable welding temperature (usually 0.5-0.8 times the melting point of the material) and begin to diffuse actively. Atoms of different materials permeate each other at the contact interface to form an atomic diffusion layer. As time goes by, the diffusion layer gradually thickens, laying the foundation for the formation and improvement of the joint.

[0050] In this embodiment, the joint formation and refinement stage is the final stage of continuous diffusion soldering technology. During this stage, atomic diffusion continues, the diffusion layer further develops, until the entire contact interface forms a uniform and strong metallurgical bond. Finally, all components of the chip heat sink are soldered to form a complete heat dissipation structure, ensuring soldering quality and efficiency.

[0051] In this embodiment, the mold structure design of the diffusion welding equipment needs to be customized according to the specific shape, size and welding process requirements of the chip heat sink. This design method ensures that the welding part 100 is accurately positioned during the welding process, and the fitting accuracy between the inner surface of the mold and the welding part 100 is extremely high, reaching ±0.05mm, thereby ensuring the welding quality.

[0052] Of course, to ensure the precise fit and positioning of the workpiece 100 during the welding process, the mold design of the diffusion welding equipment will take into account the structural characteristics of the heat sink. For example, for chip heat sinks with complex heat sink fin structures, the mold will be designed with special positioning grooves and support structures to prevent the fins from shifting and deforming during the welding process.

[0053] In addition, the mold design of the diffusion welding equipment also takes into account the ease of demolding. By setting a reasonable demolding angle and using surface coating technology (such as plating molybdenum disulfide coating to reduce the coefficient of friction), the chip heat sink can be demolded smoothly after welding, reducing damage to the surface of the weldment 100.

[0054] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A continuous diffusion welding device, characterized in that, include: The feeding unit, preheating unit, welding unit, cooling unit, and unloading unit are arranged sequentially along the welding workpiece conveying direction. A vacuuming unit is provided between each adjacent unit. Each unit has an interconnected conveying unit for receiving the welding workpiece. The material conveying direction of the feeding unit is perpendicular to the material conveying direction of the preheating unit, welding unit, cooling unit, and unloading unit, respectively. The preheating unit, welding unit, and cooling unit are arranged on the same side.

2. The continuous diffusion welding equipment according to claim 1, characterized in that, The preheating unit includes: several heating zones with progressively increasing temperatures and several pressure regulating mechanisms disposed within the heating zones.

3. The continuous diffusion welding equipment according to claim 2, characterized in that, The heating zone includes a heating furnace for accommodating the weldment and several heating units evenly distributed within the heating furnace, with the weldment placed on the heating units.

4. The continuous diffusion welding equipment according to claim 2, characterized in that, The pressure regulating mechanism includes an external interface and an airflow channel disposed at the end of the external interface, the airflow channel being connected to a cavity inside the preheating unit.

5. A continuous diffusion welding device according to claim 2, characterized in that, The temperature range of the heating zone is 800℃-1200℃.

6. The continuous diffusion welding equipment according to claim 1, characterized in that, The welding unit includes: a plurality of first lifting components, a welding device correspondingly disposed at the bottom of the first lifting components, and a receiving plate disposed below the welding device for receiving the weldment.

7. A continuous diffusion welding device according to claim 1, characterized in that, The cooling unit includes a second lifting component and a water-cooling component disposed on the second lifting component.

8. A continuous diffusion welding device according to claim 1, characterized in that, A discharge mechanism is provided on one side of the cooling unit.

9. A continuous diffusion welding device according to claim 8, characterized in that, The discharge mechanism includes: a receiving pipe disposed on one side of the conveying unit, a first switch disposed at one end of the receiving pipe, and a second switch disposed at the other end of the receiving pipe.

10. A continuous diffusion welding device according to claim 1, characterized in that, The feeding unit, preheating unit, welding unit, cooling unit, and unloading unit are all equipped with a horizontal pushing mechanism on the opposite side of their discharge ports for pushing the weldment to the next unit.

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