Welding die and diffusion welding equipment

Abstract

The invention relates to the technical field of diffusion welding, in particular to a welding mold and diffusion welding equipment. The clamping device is used for clamping a to-be-welded workpiece in diffusion welding and comprises an upper tool and a lower tool which are oppositely arranged in the first direction and at least one plastic layer, the plastic layer is arranged on at least one of the first end face, facing the lower tool, of the upper tool and the second end face, facing the upper tool, of the lower tool, and the plastic layer is used for abutting against the to-be-welded workpiece. Microcosmic unevenness of the surface of the mold can be effectively made up by arranging the plastic layer, the contact face is more uniform in the welding process, the flatness and thickness tolerance of an ultrathin sample during low-temperature diffusion welding are made up, the effect is especially crucial to welding of the ultrathin sample, and the welding quality can be remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of diffusion welding technology, specifically to a welding mold and diffusion welding equipment. Background Technology

[0002] Diffusion welding is a process that, under certain temperature and pressure, brings the surfaces to be welded into contact, causing microscopic plastic deformation at the interface, thereby expanding the physical contact between the joined surfaces. Ultimately, through diffusion between interatomic atoms at the interface, a reliable overall bond is formed. However, uneven or rough metal surfaces can significantly negatively impact welding performance and uniformity. Traditional solutions involve using high pressure or high temperature to ensure sufficient surface contact, but in low-temperature diffusion welding, especially when welding ultrathin samples, it is impossible to apply very high temperatures, and it is also impossible to compensate for the material's thickness tolerances and the flatness of the mold. This problem is particularly pronounced during the welding process, leading to poor welding results and uniformity. Summary of the Invention

[0003] The purpose of this invention is to at least solve the problem of uncompensated flatness and thickness tolerances encountered in low-temperature diffusion welding of ultrathin samples. This purpose is achieved through the following technical solution:

[0004] A first aspect of the present invention provides a welding mold for holding a workpiece to be welded during diffusion welding, comprising:

[0005] An upper tooling and a lower tooling are arranged opposite each other along a first direction. At least one of the first end face of the upper tooling facing the lower tooling and the second end face of the lower tooling facing the upper tooling is provided with a plastic layer, which is used to abut against the workpiece to be welded.

[0006] According to the welding mold of the present invention, the welding mold mainly consists of two opposing upper and lower toolings arranged along a first direction. The upper tooling has a first end face, and the lower tooling has a second end face. At least one of the two end faces is provided with a plastic layer, which abuts against the workpiece to be welded. The plastic layer has a certain elasticity, which can apply uniform pressure to the welding surface during the welding process. Even if there are microscopic unevennesses on the surface of the metal part of the mold, the plastic layer can adapt to these unevennesses through its elastic deformation, ensuring that the welding contact surface maintains good flatness, thereby improving the uniformity of the welding. When welding ultra-thin samples, due to the certain tolerance of the sample thickness, traditional metal molds are difficult to completely eliminate this influence. By providing a plastic layer on the end face, the plastic layer can adapt to the thickness tolerance of the sample during the welding process, making the welding contact surface more uniform and ensuring the welding quality. Therefore, the present invention can effectively compensate for the microscopic unevenness of the mold surface by providing a plastic layer, making the contact surface more uniform during the welding process. This effect is particularly important for welding ultra-thin samples and can significantly improve the welding quality. Secondly, due to the elasticity and adjustability of the plastic layer, it can adapt to the thickness tolerance of the sample during welding, ensuring close contact between the sample surface and the mold. This not only improves welding uniformity but also effectively reduces welding defects caused by thickness tolerances. Finally, by adding a plastic layer to the mold, sufficient pressure and contact area can be maintained at lower welding temperatures, reducing thermal damage to the welding materials while achieving a stable weld connection. This design protects the sample's performance while ensuring the reliability and consistency of the weld. In summary, this invention, through the design of the plastic layer, effectively solves the common flatness and thickness tolerance problems in low-temperature diffusion welding, providing a reliable guarantee for achieving high-quality welding of ultra-thin samples.

[0007] In addition, the welding mold according to the present invention may also have the following additional technical features:

[0008] In some embodiments of the present invention, at least one of the first end face and the second end face is provided with a limiting structure, the plastic layer is mounted on the limiting structure, and the limiting structure is used to restrict the movement of the plastic layer along a second direction, the second direction being perpendicular to the first direction.

[0009] In some embodiments of the present invention, the limiting structure includes a boss structure, and the plastic layer is disposed on the boss structure.

[0010] In some embodiments of the present invention, the plastic layer has an annular groove on one side facing the boss structure, and the boss structure is annular and is inserted into the groove.

[0011] In some embodiments of the present invention, the thickness of both the upper tooling and the lower tooling is greater than or equal to 5 mm along the first direction.

[0012] In some embodiments of the present invention, along the first direction, the thickness of the boss structure is greater than 0 mm and less than or equal to 2 mm.

[0013] In some embodiments of the present invention, the plastic layer has a ring-shaped structure, and along the second direction, the ring width of the plastic layer is greater than 0 mm and less than or equal to 2 mm.

[0014] In some embodiments of the present invention, the thickness of the plastic layer along the first direction is less than or equal to 1000 μm and greater than or equal to 100 μm.

[0015] In some embodiments of the present invention, the plastic layer is connected to the limiting structure by spray curing or assembly.

[0016] A second aspect of the present invention provides a diffusion welding apparatus, comprising:

[0017] Furnace body;

[0018] The welding mold described above is disposed inside the furnace body;

[0019] A loading device is connected to the furnace body. The loading device includes a vacuum device for evacuating the interior of the furnace body or a gas supply device for supplying protective gas into the furnace body. Attached Figure Description

[0020] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0021] Figure 1 A schematic diagram of the structure of a welding mold according to an embodiment of the present invention is shown.

[0022] Figure 2 A schematic front view of the exploded structure of a welding mold according to an embodiment of the present invention is shown.

[0023] Figure 3 A schematic front view of a welding mold according to an embodiment of the present invention is shown;

[0024] Figure 4 for Figure 3 A cross-sectional view of the AA plane;

[0025] Figure 5 for Figure 4 A magnified view of a section at point B in the middle;

[0026] Figure 6 A schematic diagram of the structure of a plastic layer according to an embodiment of the present invention is shown.

[0027] The attached figures are labeled as follows:

[0028] 100. Welding molds;

[0029] 10. Mounting fixture; 11. First boss structure;

[0030] 20. Lower tooling; 21. Second boss structure;

[0031] 30. First plastic layer; 31. Groove; 40. Second plastic layer;

[0032] 200. Workpiece to be welded. Detailed Implementation

[0033] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0034] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0035] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0036] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "over," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure is flipped, an element described as "below other elements or features" or "below other elements or features" would subsequently be oriented "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations.

[0037] like Figures 1 to 6 As shown, according to an embodiment of the present invention, a welding mold 100 is provided for clamping a workpiece 200 to be welded during diffusion welding. The welding mold 100 includes components along a first direction (e.g., ...). Figure 2 The upper fixture 10 and the lower fixture 20 are arranged opposite each other (in the direction of the middle arrow c), and at least one plastic layer is provided on at least one of the first end face of the upper fixture 10 facing the lower fixture 20 and the second end face of the lower fixture 20 facing the upper fixture 10. The plastic layer is used to abut against the workpiece 200 to be welded.

[0038] According to the welding mold 100 of this embodiment, the welding mold 100 mainly consists of two opposing upper tooling 10 and lower tooling 20, and at least one of the first end face of the upper tooling 10 and the second end face of the lower tooling 20 is provided with a plastic layer. The plastic layer on the end face has a certain elasticity, which can apply uniform pressure to the welding surface during the welding process. Even if there are microscopic unevennesses on the surface of the metal part of the mold, the plastic layer can adapt to these unevennesses through its elastic deformation, ensuring that the welding contact surface maintains good flatness, thereby improving the uniformity of the weld. When welding ultra-thin samples, due to the certain tolerance of the sample thickness, traditional metal molds cannot completely eliminate this influence. By providing a plastic layer on the end face, the plastic layer can adapt to the thickness tolerance of the sample during the welding process, making the welding contact surface more uniform and ensuring welding quality. Therefore, the present invention can effectively compensate for the microscopic unevenness of the mold surface by providing a plastic layer, making the contact surface more uniform during the welding process. This effect is particularly important for welding ultra-thin samples and can significantly improve welding quality. Secondly, due to the elasticity and adjustability of the plastic layer, it can adapt to the thickness tolerance of the sample during welding, ensuring close contact between the sample surface and the mold. This not only improves welding uniformity but also effectively reduces welding defects caused by thickness tolerances. Finally, by adding a plastic layer to the mold, sufficient pressure and contact area can be maintained at lower welding temperatures, reducing thermal damage to the welding materials while achieving a stable weld connection. This design protects the sample's performance while ensuring the reliability and consistency of the weld. In summary, this invention, through the design of the plastic layer, effectively solves the common flatness and thickness tolerance problems in low-temperature diffusion welding, providing a reliable guarantee for achieving high-quality welding of ultra-thin samples.

[0039] In some embodiments, at least one of the first end face and the second end face is provided with a limiting structure, the plastic layer is mounted on the limiting structure, and the limiting structure is used to restrict the plastic layer along a second direction (e.g., Figure 2 The direction of the arrow d) moves, and the second direction is perpendicular to the first direction. Through the design of the limiting structure, the plastic layer will not move due to external force or thermal expansion during welding, thus maintaining tight contact between the plastic layer and the boss structure, ensuring the quality and consistency of the welded joint.

[0040] In some implementations, the limiting structure can employ a groove design, with the edge of the plastic layer embedded in the groove. The depth and width of the groove need to be precisely controlled to ensure that the plastic layer is securely fixed within the groove without affecting thermal expansion during the welding process.

[0041] In the preferred embodiment, the limiting structure includes a boss structure, and a plastic layer is disposed on the boss structure.

[0042] Specifically, the boss structure is annular. Through its symmetrical geometry, the annular boss structure enables uniform encirclement and pressure application of the workpiece 200 during welding, significantly improving the uniformity of the weld contact surface and reducing welding defects. Secondly, the annular structure design better accommodates workpieces of various shapes, especially circular or ring-shaped workpieces, making the welding mold 100 more versatile and capable of handling a variety of complex welding tasks. Simultaneously, the annular boss structure helps reduce localized stress concentration during welding, further improving the quality and reliability of the welding mold 100.

[0043] like Figure 1 and Figure 6 As shown, the boss structure is further designed in a ring shape, and the plastic layer is also correspondingly ring-shaped. To enhance the connection and stability between the plastic layer and the boss structure, a groove 31 is designed on the side of the plastic layer facing the boss structure. This groove 31 is used to cover and tightly fit the boss structure, and the boss structure is inserted into the groove 31. The depth and width of the groove 31 should be precisely designed according to the dimensions of the boss structure to ensure that the plastic layer can firmly cover the boss structure. The depth of the groove 31 should be slightly greater than the height of the boss to provide sufficient covering space, while the width of the groove 31 should match the width of the boss to ensure the stability of the plastic layer. By setting the groove 31 on the plastic layer and covering the boss structure, the plastic layer can be firmly fixed to the boss structure, preventing slippage or detachment due to thermal expansion or pressure changes during welding. This significantly improves the stability and reliability of the welding process. The groove 31 design ensures a tight fit between the plastic layer and the boss structure, allowing for a more uniform distribution of welding pressure during welding, thereby improving the uniformity of the weld contact surface and reducing welding defects. Meanwhile, due to the tight fit between the groove 31 and the boss structure, the contact surface maintains a high degree of consistency during welding, reducing stress concentration during welding and improving welding accuracy and the quality of the final welding mold 100. Furthermore, the covering design of the groove 31 reduces friction and displacement between the plastic layer and the boss structure during welding, reducing wear and extending the service life of the welding mold 100. Precision manufacturing technology ensures a perfect fit between the groove 31 and the boss structure, further enhancing the mold's durability.

[0044] In some embodiments, the thickness of both the upper tooling 10 and the lower tooling 20 along the first direction is greater than or equal to 5 mm. To ensure that the welding mold 100 can rapidly and evenly transfer heat during welding, tooling with a thickness of 5 mm or more has good thermal conductivity, which improves welding efficiency and avoids localized overheating. Simultaneously, the larger thickness design helps improve the overall rigidity of the tooling, thus providing more stable support during welding and preventing the tooling from deforming due to heat or bending under stress, which could affect welding accuracy. Furthermore, the thicker tooling can better distribute and withstand the pressure during welding, thereby reducing stress concentration and fatigue damage. This not only increases the service life of the mold but also reduces production interruptions and maintenance costs caused by mold damage. Therefore, the thickness of the upper tooling 10 and the lower tooling 20 is designed to be greater than or equal to 5 mm, giving the entire welding mold 100 higher rigidity and stability during welding. This helps maintain the shape of the mold when welding pressure is applied, ensuring welding accuracy and consistency.

[0045] In some embodiments, the thickness of the boss structure along the first direction is greater than 0 mm and less than or equal to 2 mm. A boss structure thickness of less than or equal to 2 mm allows for more precise control of the thickness of the welding area during the welding process. This helps improve welding accuracy, especially when processing ultra-thin samples, enabling a more uniform weld contact surface and reducing welding defects. The thinner boss structure facilitates rapid conduction and heat dissipation, reducing localized heat accumulation during welding and preventing deformation or damage to the welded sample due to overheating, thereby improving weld quality.

[0046] In some implementations, along the second direction, the annular width of the plastic layer is greater than 0 mm and less than or equal to 2 mm. A narrower plastic layer design allows for more precise control of the welding area size, reducing the impact of excess material on the welding effect and ensuring the uniformity and consistency of the welding mold. Simultaneously, by precisely controlling the width of the plastic layer, the use and waste of excess material during welding can be reduced. This not only lowers costs but also improves the efficiency and environmental friendliness of the welding operation.

[0047] Understandably, since the width of the plastic layer is less than or equal to 2 mm, the ring width of the boss structure is also less than or equal to 2 mm, and slightly smaller than the width of the plastic layer. Because the ring width of the plastic layer is slightly larger than the boss structure, this means that the plastic layer can form a covering effect during welding, completely covering the edge of the boss. This design helps reduce edge stress concentration during welding, preventing material warping or detachment. The groove 31 of the plastic layer should precisely match the width of the boss, and the inner diameter of the groove 31 should be slightly larger than the width of the boss to ensure that the plastic layer can fully cover the boss during welding. Simultaneously, the depth of the groove 31 also needs to be slightly greater than the thickness of the boss to provide sufficient coverage depth. This matching design between the boss structure and the width of the plastic layer ensures that the plastic layer always maintains effective coverage of the boss during welding, which enhances the stability of the welding process and prevents welding defects caused by edge warping or slippage.

[0048] In some embodiments, the thickness of the plastic layer along the first direction is less than or equal to 1000 μm and greater than or equal to 100 μm. The thickness of the plastic layer should match the boss structure to ensure that the plastic layer can completely cover and encapsulate the boss structure during welding, while avoiding excessive compression or failure. For example, a plastic layer thickness between 100 μm and 300 μm is suitable for welding applications requiring high precision and thin-layer structures. In this case, the plastic layer can provide sufficient flexibility to accommodate small thickness tolerances while ensuring the flatness of the weld surface. A plastic layer thickness between 300 μm and 1000 μm, within this thicker range, can provide greater cushioning and compression capacity, suitable for applications requiring greater pressure or stress dispersion during welding. A thicker plastic layer can also better fill microscopic unevenness on the weld contact surface, improving the overall quality of the weld. In summary, the design of the plastic layer thickness, ranging from 100μm to 1000μm, allows the plastic layer to adapt to minor unevenness on the workpiece surface during welding, thereby improving the uniformity of the weld contact surface and reducing welding defects. A thinner plastic layer is suitable for high-precision welding operations, while a thicker layer provides additional cushioning during high-pressure welding, preventing damage to the workpiece 200 or the welding mold 100 during the welding process. This flexibility allows the welding mold 100 to meet different welding process requirements. Furthermore, the moderate plastic layer thickness ensures sufficient structural support during welding while maintaining a certain degree of elasticity to accommodate micro-deformations during welding, thereby improving the strength and stability of the welding mold 100.

[0049] In some embodiments, the plastic layer is made of at least one of polytetrafluoroethylene (PTFE), polyimide, or polyetheretherketone (PEEK), with an elastic modulus greater than or equal to 500 MPa and a heat resistance temperature greater than or equal to 250°C. First, the properties of these three materials are described: PTFE has excellent chemical resistance and a low coefficient of friction, making it suitable for welding environments requiring anti-adhesion and chemical corrosion resistance. Its heat resistance temperature exceeds 250°C, and its elastic modulus is close to 500 MPa, allowing it to maintain stable physical properties at high temperatures. Polyimide is known for its excellent high-temperature resistance and mechanical strength, and is commonly used in welding molds 100 that require long-term operation at high temperatures. Its elastic modulus is greater than 500 MPa, and its heat resistance temperature can reach 300°C or even higher, making it suitable for maintaining the stability of the plastic layer under extreme temperature conditions. PEEK combines high mechanical strength, abrasion resistance, and heat resistance, with an elastic modulus typically exceeding 500 MPa and a heat resistance temperature reaching 300°C. It maintains excellent performance under high temperature and high stress environments, making it an ideal choice for demanding welding operations. Using materials with an elastic modulus greater than or equal to 500 MPa ensures that the plastic layer can withstand high mechanical stress during welding without significant deformation, thus maintaining the flatness and consistency of the welded contact surface and improving welding precision. The material design with a heat resistance temperature greater than or equal to 250℃ allows the plastic layer to work stably for a long time under high-temperature welding conditions, avoiding welding quality problems caused by material thermal degradation or softening, thereby improving the safety and reliability of welding operations.

[0050] Understandably, the plastic layer can be polytetrafluoroethylene (PTFE), polyimide, or polyetheretherketone (PEEK), or composite materials with these as the main component. For example, combining PTFE with glass fiber or carbon fiber can improve the material's mechanical strength and rigidity while maintaining low friction and chemical resistance; PEEK can be combined with ceramic microparticles to enhance its thermal conductivity and wear resistance, thus providing better thermal management and durability in high-temperature welding operations. Different polymer materials can also be blended using blending techniques to improve the overall performance of the material. For instance, polyimide can be combined with PEEK using melt blending to form a composite material that is both high-temperature resistant and has a low coefficient of friction, suitable for high-temperature precision welding.

[0051] In some implementations, the plastic layer is connected to the boss structure via assembly. Assembly methods include spray-curing connection, snap-fit ​​connection, or adhesive bonding. First, the plastic layer material can be uniformly coated onto the surface of the boss structure using a spraying process. This method is suitable for molds with complex shapes or requiring precise thickness control. After spraying, the material evenly covers the entire boss surface, ensuring no dead corners. After spraying, the plastic layer needs to be cured. Curing can be achieved through heat curing, ultraviolet curing, or chemical curing, depending on the characteristics of the plastic layer material. During curing, the plastic layer material bonds tightly to the boss structure, forming a robust coating. Spraying is particularly suitable for mold structures with complex shapes or requiring precise coating thickness control, ensuring that the plastic layer evenly covers the boss surface during welding, providing a consistent welding effect. Second, the plastic layer can be installed onto the boss structure via a snap-fit ​​connection. The boss structure can be designed with slots distributed along its edges to accommodate the snaps on the plastic layer. The shape and depth of the slots should match the snaps on the plastic layer to ensure a tight fit. The edges of the plastic layer are designed with a flexible snap-fit ​​structure. The snaps can be hook-shaped, serrated, or similar locking mechanisms to ensure automatic locking after being pressed into the slots. Through the tight fit between the snaps and slots, the plastic layer is firmly fixed to the boss structure, preventing loosening or displacement caused by vibration or thermal expansion during welding. Finally, the plastic layer can be bonded to the boss structure using adhesives such as epoxy resin, polyurethane, or acrylic adhesives. These adhesives possess high strength, high temperature resistance, and good chemical stability, making them suitable for long-term resistance to the thermal and mechanical stresses generated during welding. The bonding process involves aligning the plastic layer with the boss structure and gently pressing it to evenly distribute the adhesive and fill any gaps between the contact surfaces. A clamp or vacuum pressing device can be used to maintain close contact between the plastic layer and the boss structure until the adhesive cures. The assembly process in this embodiment requires ensuring a tight fit between the plastic layer and the boss structure, avoiding gaps or loosening. During assembly, pressure can be applied to tightly bond the plastic layer to the boss structure, ensuring that the plastic layer will not shift or detach during use. For some high-precision applications, secondary processing can be performed after assembly to ensure the flatness and thickness accuracy of the plastic layer. Connecting the plastic layer via assembly simplifies the installation process and is suitable for welding molds 100 that require frequent replacement or maintenance. Furthermore, the assembly method allows for the use of plastic layers of different thicknesses or materials, enhancing the adaptability of the welding mold 100.

[0052] In the optimal embodiment, the upper tooling 10 has a first boss structure 11 on its first end face, and the lower tooling 20 has a second boss structure 21 on its second end face. The first boss structure 11 and the second boss structure 21 are arranged opposite to each other. There are also two plastic layers: a first plastic layer 30 and a second plastic layer 40. The first plastic layer 30 is fitted onto the first boss structure 11, and the second plastic layer 40 is fitted onto the second boss structure 21. By setting the first boss structure 11 and the second boss structure 21 on the upper tooling 10 and the lower tooling 20 respectively, and fitting a plastic layer onto each boss structure, the symmetrical distribution of pressure during welding is ensured. This design effectively improves the uniformity of the welding contact surface and reduces welding defects caused by uneven stress on one side. Simultaneously, the double-layer plastic layer design better resists mechanical and thermal stresses that may occur during welding, ensuring the stability and reliability of the welding process, especially under high temperature and high pressure conditions.

[0053] Understandably, the first plastic layer 30 and the second plastic layer 40 can be made of different polymer materials. For example, the first plastic layer 30 could use polytetrafluoroethylene (PTFE) to provide excellent chemical resistance and a low coefficient of friction, while the second plastic layer 40 could use polyetheretherketone (PEEK) to improve mechanical strength and wear resistance. Such a combination of materials can be customized according to the needs of the actual application, providing more flexible welding solutions.

[0054] It is understandable that the surface of the workpiece 200 to be welded is made of metallic copper. Metallic copper has high thermal conductivity, which helps to evenly distribute heat, prevent localized overheating, and avoid welding defects.

[0055] This embodiment also provides a diffusion welding apparatus, which includes a furnace body, the aforementioned welding mold 100, and a loading device. The welding mold 100 is disposed within the furnace body, and the loading device is connected to the furnace body. The loading device includes a vacuum device for evacuating the interior of the furnace body or a gas supply device for supplying protective gas into the furnace body. By providing a vacuum environment or protective atmosphere within the furnace body, oxidation and contamination during the welding process can be effectively prevented, ensuring the high quality of the welding mold 100. Precise temperature and atmosphere control further guarantees the stability and consistency of the welding process.

[0056] Understandably, diffusion welding equipment also includes a temperature control device. Specifically, to ensure precise temperature control during the diffusion welding process, multiple temperature sensors and temperature control devices can be installed inside the furnace. By monitoring and adjusting the furnace temperature in real time, it is ensured that the welding process is maintained within the optimal temperature range.

[0057] Understandably, diffusion welding equipment also includes an atmosphere control and monitoring system. Specifically, an atmosphere monitoring system is added to the gas supply unit to monitor the gas composition, pressure, and flow rate inside the furnace in real time, ensuring that the protective gas is always maintained within the set range. This helps prevent welding quality instability caused by changes in gas composition. Furthermore, the entire welding process can be controlled by an automated system, including vacuum extraction, gas supply, and temperature regulation, ensuring that each step is executed according to predetermined process parameters and reducing errors caused by human intervention.

[0058] Understandably, the welding temperature inside the diffusion welding furnace can be controlled between 220°C and 350°C. For common metallic materials, the temperature range for diffusion welding is roughly between 600°C and 1200°C. In contrast, this embodiment can control the diffusion welding temperature between 220°C and 350°C because the welding mold 100 uses high-temperature resistant polymer materials, such as polytetrafluoroethylene, polyimide, or polyetheretherketone. These materials not only maintain physical stability at high temperatures but also achieve effective diffusion welding at lower temperatures. Their inclusion reduces the required welding temperature, allowing welding to be performed between 220°C and 350°C. Furthermore, the optimized welding process, with the plastic layer providing sufficient surface smoothness and pressure distribution at lower temperatures, allows for good contact and diffusion on the workpiece surface (especially the copper surface), further reducing the required welding temperature. Furthermore, the surface of the workpiece 200 to be welded is metallic copper. Copper has high electrical and thermal conductivity, meaning that during welding, heat can be rapidly and evenly distributed in the welding area. Although conventional diffusion welding is typically performed at higher temperatures, copper's high thermal conductivity allows for uniform atomic diffusion at relatively lower temperatures, resulting in a robust weld joint. Finally, the optimized design of the welding mold 100, including the combination of the plastic layer and the boss structure, ensures sufficient contact pressure and surface flatness at lower temperatures, further reducing the required welding temperature. In summary, diffusion welding between 220°C and 350°C significantly reduces energy consumption during the welding process, improving energy efficiency. The lower welding temperature reduces the risk of thermal stress and deformation after material heating, especially for precision components and thin-walled materials, thus improving the stability of the welding mold 100.

[0059] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A welding die for clamping a workpiece to be welded in a diffusion welding, characterized in that Comprising: an upper tooling and a lower tooling oppositely arranged along a first direction, at least one of a first end surface of the upper tooling facing the lower tooling and a second end surface of the lower tooling facing the upper tooling is provided with a plastic layer for abutting against the workpiece to be welded.

2. The welding die of claim 1, wherein, At least one of the first end surface and the second end surface is provided with a limiting structure, the plastic layer is mounted on the limiting structure, the limiting structure is used to limit the movement of the plastic layer along a second direction, the second direction is perpendicular to the first direction.

3. The welding die of claim 2, wherein, The limiting structure comprises a boss structure, and the plastic layer is covered on the boss structure.

4. The welding die of claim 3, wherein, A side of the plastic layer facing the boss structure is provided with an annular groove, and the boss structure is in the form of a circular ring and is connected to the groove in a plug-in manner.

5. The welding die of claim 4, wherein, Along the first direction, the thickness of the upper tooling and the lower tooling is greater than or equal to 5mm.

6. The welding die of claim 4, wherein, Along the first direction, the thickness of the boss structure is greater than 0mm and less than or equal to 2mm.

7. The welding die of claim 4, wherein, The plastic layer is in the form of an annular structure, and along the second direction, the ring width of the plastic layer is greater than 0mm and less than or equal to 2mm.

8. The welding die of claim 1, wherein, Along the first direction, the thickness of the plastic layer is less than or equal to 1000μm and greater than or equal to 100μm.

9. The welding die of any one of claims 2 to 7, wherein, The plastic layer is connected to the limiting structure by assembly.

10. A diffusion bonding apparatus characterized by comprising: Comprising: a furnace body; a welding mold according to any one of claims 1 to 9, the welding mold is arranged in the furnace body; a loading device, the loading device is in communication with the furnace body, the loading device comprises a vacuum device for vacuumizing the inside of the furnace body or a gas supply device for providing a protective gas into the furnace body.

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