A joint structure for high-energy beam welding and a method of processing and welding the same

Abstract

The application discloses a joint structure of high-energy beam welding and a processing and welding method thereof, and aims at solving the problems of stress concentration, gas residue, heat affected zone and difficult control of welding quality in the prior art. The joint structure comprises coaxially assembled base material I and base material II; a first annular groove is arranged on a welding surface of the base material I, a second annular groove is arranged on a welding surface of the base material II, the groove widths of the first annular groove and the second annular groove are consistent and the positions of the first annular groove and the second annular groove correspond; the first annular groove and the second annular groove form an annular stress relief channel after the base material I and the base material II are assembled; at least one exhaust channel is arranged on the base material I and / or the base material II, one end of the exhaust channel is communicated with the annular stress relief channel, and the other end is used for communicating with an external environment; and the maximum radial dimension of the communicated position of the exhaust channel and the annular stress relief channel is smaller than the groove width of the annular stress relief channel. The structure can eliminate stress concentration during welding, and prevent the initiation and expansion of cracks after welding.

Description

Technical Field

[0001] This invention relates to a high-energy beam welding method, specifically to a joint design structure for electron beam welding of circumferential welds in automobile manufacturing, which is particularly suitable for welding key components such as battery packs, motor and electronic control housings, and transmission systems in new energy vehicles. Background Technology

[0002] As a leading force in industrial development, the automotive industry has achieved leapfrog progress and advancements in recent years. This presents both opportunities and challenges for auto parts manufacturers, with welding technology being an indispensable process for many key components. Industry reports indicate that high-energy beam (such as electron beam and laser) welding equipment now accounts for over 30% of applications in the new energy vehicle sector. With the increasing demand for lightweight and compact designs in core components such as battery packs, motors, and transmission gears, the application scenarios for high-energy beam welding technology are rapidly expanding.

[0003] High-energy beam welding, as a high-energy-density welding method, has advantages such as large weld depth, small heat-affected zone, and minimal deformation. In the automotive manufacturing field, especially in the connection of core components for new energy vehicles, high-energy beam welding technology is playing an increasingly important role. For example, Chinese utility model patent CN206029007U discloses an electron beam welding lap joint structure, Chinese invention patent CN106271007A discloses an electron beam welding joint structure, and Chinese invention patent CN106695104A discloses a venting and locking structure for eliminating porosity in electron beam welds of annular parts, etc. However, in practical applications, the following problems still exist:

[0004] (1) Stress concentration: Existing straight-through butt welded joints are prone to stress concentration in high-strength automotive components, which affects the safety and fatigue life of the corresponding structure;

[0005] (2) Gas residue: The gas generated during the welding process cannot be discharged in time, which can easily form porosity defects in components with high sealing requirements such as battery pack housing and motor housing, thus leading to delayed cracking;

[0006] (3) The heat-affected zone is difficult to control: materials such as aluminum alloys and high-strength steel used in automobiles are sensitive to heat input, which makes it difficult to control the heat-affected zone.

[0007] (4) Quality control is difficult: Due to the multiple influences of material properties, welding parameters, and environmental factors, the stability of welding quality is difficult to guarantee. Summary of the Invention

[0008] The purpose of this invention is to provide a joint structure for high-energy beam welding and its processing and welding method, so as to solve the technical problems of stress concentration, gas residue, heat-affected zone and difficulty in controlling welding quality in existing welding technologies.

[0009] To achieve the above objectives, the technical solution provided by this invention is as follows:

[0010] A joint structure for high-energy beam welding is characterized by comprising coaxially assembled base material one and base material two.

[0011] The contact surface between base material 1 and base material 2 is defined as its welding surface; a first annular groove is provided on the welding surface of base material 1, and a second annular groove is provided on the welding surface of base material 2. The width of the first annular groove and the second annular groove are the same and their positions are corresponding. Both are located at the bottom of the weld at the welding point of base material 1 and base material 2; after base material 1 and base material 2 are assembled, an annular stress relief channel is formed between the first annular groove and the second annular groove.

[0012] At least one exhaust channel is provided on the first and / or second base material, and one end of the exhaust channel is connected to the annular stress relief channel, while the other end is used to connect to the external environment; the maximum radial dimension at the connection between the exhaust channel and the annular stress relief channel is less than the groove width of the annular stress relief channel.

[0013] Furthermore, the parent material is coaxially assembled on the outside of the second parent material, and the outer diameter of the second parent material is adapted to the inner diameter of the first parent material; the first annular groove is provided on the inner wall of the first parent material, and the second annular groove is provided at the corresponding position on the outer wall of the second parent material.

[0014] Furthermore, the parent material is coaxially assembled at one end of the parent material two, and the first annular groove is provided on the end face of the parent material one near the end of the parent material two; the second annular groove is provided at the corresponding position on the end face of the parent material two.

[0015] Furthermore, the exhaust channel is at least one of a straight through hole, a zigzag hole, and a spiral hole;

[0016] The through hole is a circular or rectangular through-hole;

[0017] The zigzag hole is composed of multiple circular or rectangular straight channels connected at a specific angle.

[0018] The spiral hole is a spiral venting hole with constant pitch or variable pitch.

[0019] Furthermore, when there are two or more exhaust channels, they are arranged at equal intervals along the circumference of the first and / or second parent materials.

[0020] Furthermore, the groove width L of the first annular groove and the second annular groove is: Where d is the depth of the weld at the welding point on the welding surface after the assembly of base material one and base material two.

[0021] Furthermore, the inner sides of the groove edges of the first and second annular grooves are provided with chamfers that are aligned with each other.

[0022] Furthermore, the radial cross-section of the annular stress-relief channel is a rectangular structure, and the four corners of the rectangular structure are provided with rounded chamfers.

[0023] This invention also provides a method for processing and welding a joint structure for high-energy beam welding, characterized by the following steps:

[0024] Step 1: Process the materials to obtain base material 1 and base material 2 according to the preset requirements;

[0025] Step 2: Based on the maximum torque that base material 1 and base material 2 can withstand, calculate the depth of the weld at the weld joint after the two are assembled, and accordingly process the first annular groove and the second annular groove at the corresponding positions of the weld surfaces of base material 1 and base material 2.

[0026] Step 3: Based on the dimensions and material properties of base material 1 and base material 2, determine the number, size and location of exhaust channels, and process the corresponding exhaust channels in base material 1 and / or base material 2.

[0027] Step 4: Assemble base material one and base material two, and check the axial and / or radial fit of the two with a feeler gauge. If the fit meets the requirements, proceed to step 5; if the fit does not meet the requirements, scrap the material or rework it according to the preset process requirements until the fit meets the requirements, and then proceed to step 5.

[0028] Step 5: Using high-energy beam welding technology, base material one and base material two are welded at the predetermined weld seam to obtain the high-energy beam welded joint structure.

[0029] Furthermore, in step 4, the requirement for fit refers to the axial and / or radial gap between the first base material and the second base material being less than or equal to 0.03 mm.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] 1. This invention provides corresponding first and second annular grooves on base material one and base material two, both located at the bottom of the weld joint to be welded on base material one and base material two, forming annular stress relief channels. At the same time, an exhaust channel connected to the annular stress relief channel is provided. This not only eliminates stress concentration in the welded joints of key automotive components, improving fatigue life and collision safety, but also allows for timely exhaust of gas during the welding process, preventing gas blasting during welding and ensuring the safety and quality of the welding process.

[0032] 2. The exhaust channel of the present invention can be selected from at least one of straight holes, zigzag holes, and spiral holes according to actual needs, thereby improving the applicability to materials, especially for automotive aluminum alloys, high-strength steel and other materials, to optimize their welding characteristics and reduce the heat-affected zone.

[0033] 3. This invention can achieve a smaller weld width under the same weld strength, reduce the heat-affected zone, and reduce design redundancy, supporting welding of thinner base materials, thus providing technical support for lightweight automotive design.

[0034] 4. The processing method of the present invention is simple and has low precision requirements, which can reduce rework rate and scrap rate, and meet the strict cost control requirements of the automotive industry.

[0035] 5. This invention can effectively prevent the generation and propagation of cracks caused by post-weld stress, and can effectively reduce the processing difficulty and cost for parts with special structures. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of a joint structure according to a high-energy beam welding embodiment of the present invention;

[0037] Figure 2 yes Figure 1 Enlarged view of part A;

[0038] Figure 3 This is a schematic diagram of the zigzag hole structure in Embodiment 1 of the high-energy beam welding joint structure of the present invention;

[0039] Figure 4 This is a schematic diagram of the spiral hole structure in Embodiment 1 of the high-energy beam welding joint structure of the present invention.

[0040] Explanation of reference numerals in the attached figures:

[0041] 1-Main material one, 2-Main material two, 3-First annular groove, 4-Second annular groove, 5-Exhaust channel. Detailed Implementation

[0042] To make the objectives, advantages, and features of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Those skilled in the art should understand that these embodiments are merely used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0043] Example 1

[0044] like Figure 1 As shown, this embodiment provides a joint structure for high-energy beam welding, including coaxially assembled base material 1 and base material 2. Base material 1 and base material 2 are typically automotive aluminum alloys, high-strength steels, or dissimilar materials.

[0045] The contact surface between base material 1 and base material 2 is defined as its welding surface. A first annular groove 3 is provided on the welding surface of base material 1, and a second annular groove 4 is provided on the welding surface of base material 2. The groove widths of the first annular groove 3 and the second annular groove 4 are the same and their positions correspond. Both are located at the bottom of the weld seam at the point where base material 1 and base material 2 are to be welded. After the base material 1 and base material 2 are assembled, an annular stress relief channel is formed between the first annular groove 3 and the second annular groove 4. The design of this annular stress relief channel can improve the safety of the joint structure, effectively eliminate stress concentration in the welded joint of key automotive components, and improve fatigue life and collision safety.

[0046] At least one venting channel 5 is provided on the base material 1 and / or the base material 2, with one end of the venting channel 5 communicating with the annular stress-relieving channel and the other end used to communicate with the external environment; the maximum radial dimension of the venting channel 5 at the connection with the annular stress-relieving channel is smaller than the groove width of the annular stress-relieving channel. The design of the venting channel 5 can prevent gas pores during welding, thereby ensuring welding quality.

[0047] like Figure 1 As shown, the parent material 1 is coaxially assembled on the outside of the parent material 2, and the outer diameter of the parent material 2 is adapted to the inner diameter of the parent material 1; the first annular groove 3 is provided on the inner wall of the parent material 1, and the second annular groove 4 is provided at the corresponding position on the outer wall of the parent material 2.

[0048] The exhaust channel 5 in this embodiment can be determined according to the size and material of the base material 1 and the base material 2, and can be selected from one of the following: straight hole, zigzag hole, and spiral hole.

[0049] Among them, such as Figure 2 As shown, the through hole is a circular or rectangular through hole. It is used for thin-walled components, such as transmission components of new energy vehicles. Through holes with a diameter of about 0.3 to 2.0 mm (the specific size can also be adjusted according to the actual situation) can be opened at the corresponding positions on the base material 1 and / or base material 2. It can be an inclined hole, connecting the annular stress relief channel with the external environment.

[0050] like Figure 3 As shown, the zigzag hole is composed of multiple circular or rectangular straight channels connected at a specific angle. It is suitable for complex structures where it is not suitable to machine through holes internally. The use of multiple zigzag exhaust channels effectively extends the exhaust path.

[0051] like Figure 4 As shown, the spiral hole is a spiral exhaust hole with equal pitch or variable pitch. The spiral hole is specially designed for transmission system components with high torque. Variable pitch spiral exhaust channels are machined on the joint surface to optimize gas flow and at the same time optimize the welding quality of high-strength steel materials.

[0052] For large-sized transmission system components, a composite exhaust structure combining straight-through holes and spiral holes can be used to meet the mixed welding requirements of high-strength steel and aluminum alloys for vehicle bodies.

[0053] It should be noted that the specific shape of the exhaust channel 5 can also be determined according to the actual situation, with the aim of dissipating the heat during the welding process in a timely manner without affecting the properties of the base material.

[0054] When there are two or more exhaust channels 5, they are arranged at equal intervals along the circumference of the first parent material 1 and / or the second parent material 2 to ensure uniform heat dissipation.

[0055] In this embodiment, the groove width L of the first annular groove 3 and the second annular groove 4 is: Where d represents the depth of the weld at the welding point on the welding surface of base material 1 and base material 2 after assembly; simultaneously, this embodiment also provides mutually aligned chamfers on the inner sides of the groove edges of the first annular groove 3 and the second annular groove 4, so that the weld smoothly connects with the annular stress relief channel. This design can achieve a smaller weld width and reduce the heat-affected zone under the same weld strength, and has less design redundancy. Therefore, it supports welding thinner base materials and provides technical support for lightweight automotive design.

[0056] Furthermore, in this embodiment, the radial cross-section of the annular stress-relieving channel is a rectangular structure, and the four corners of the rectangular structure are provided with rounded chamfers. Of course, the annular stress-relieving channel can also be designed with other shapes depending on the actual situation, as long as it is connected to the weld and the venting channel 5.

[0057] This embodiment also provides a method for processing and welding a joint structure for high-energy beam welding, including the following steps:

[0058] Step 1: Process the base material 1 and base material 2 according to the preset requirements. Conventional processing methods can be used to ensure that the structure and dimensions of base material 1 and base material 2 meet the design requirements.

[0059] Step 2: Based on the maximum torque that base material 1 and base material 2 can withstand, calculate the depth of the weld at the weld joint after they are assembled, and accordingly process the first annular groove 3 and the second annular groove 4 at the corresponding positions of the weld surfaces of base material 1 and base material 2.

[0060] Step 3: Based on the dimensions and material properties of base material 1 and base material 2, determine the number, size and location of exhaust channels 5, and process the corresponding exhaust channels 5 in base material 1 and / or base material 2 to ensure that they are connected to the annular stress relief channel.

[0061] In addition, corresponding process steps can be set at other joint positions of base material 1 and base material 2. The height of the process steps should not be too high in order to ensure the joint accuracy of the welding surfaces of the two materials.

[0062] Step 4: Assemble base material 1 and base material 2, and check their axial and / or radial fit using a feeler gauge. If the fit meets the requirements, proceed to step 5; if the fit does not meet the requirements, scrap the material or rework it according to the preset process requirements until the fit meets the requirements, then proceed to step 5. In this embodiment, the fit requirement means that the axial and / or radial gap between base material 1 and base material 2 is less than or equal to 0.03 mm.

[0063] Step 5: Using high-energy beam welding technology, the base material 1 and base material 2 are welded at the predetermined weld seam to obtain the high-energy beam welded joint structure.

[0064] The design of this embodiment can effectively solve the problems of stress concentration, gas residue, and heat-affected zone control in the welding of automotive parts in the prior art, thereby improving welding quality and production efficiency.

[0065] The processing and welding methods in this embodiment are simple, have low precision requirements, and can simultaneously process the heat-treated carburized layer of the base material. By improving welding quality and efficiency, the rework rate and scrap rate are reduced, thus meeting the strict cost control requirements of the automotive industry.

[0066] Example 2

[0067] The difference from Embodiment 1 is that in this embodiment, the base material 1 is coaxially assembled to one end of the base material 2, and the first annular groove 3 is provided on the end face of the base material 1 near the end of the base material 2; the second annular groove 4 is provided at the corresponding position on the end face of the base material 2. During welding, the welding surfaces of both are located at the shaft end. The remaining structure and method are the same as in Embodiment 1, and will not be repeated here.

[0068] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein, and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present invention.

Claims

1. A joint structure for high-energy beam welding, characterized in that: Including coaxially assembled base material one (1) and base material two (2); The contact surface between base material 1 (1) and base material 2 (2) is defined as its welding surface; a first annular groove (3) is provided on the welding surface of base material 1 (1), and a second annular groove (4) is provided on the welding surface of base material 2 (2). The groove width of the first annular groove (3) and the second annular groove (4) are the same and their positions are corresponding. Both are located at the bottom of the weld at the welding point of base material 1 (1) and base material 2 (2); after the base material 1 (1) and base material 2 (2) are assembled, an annular stress relief channel is formed between the first annular groove (3) and the second annular groove (4). At least one exhaust channel (5) is provided on the first (1) and / or the second (2) of the parent material, and one end of the exhaust channel (5) is connected to the annular stress relief channel, and the other end is used to connect to the external environment; the maximum radial dimension of the exhaust channel (5) connected to the annular stress relief channel is less than the groove width of the annular stress relief channel.

2. The joint structure for high-energy beam welding according to claim 1, characterized in that: The first parent material (1) is coaxially assembled on the outside of the second parent material (2), and the outer diameter of the second parent material (2) is adapted to the inner diameter of the first parent material (1); the first annular groove (3) is provided on the inner wall of the first parent material (1), and the second annular groove (4) is provided on the corresponding position on the outer wall of the second parent material (2).

3. The joint structure for high-energy beam welding according to claim 1, characterized in that: The first parent material (1) is coaxially assembled at one end of the second parent material (2), and the first annular groove (3) is provided on the end face of the first parent material (1) near the end of the second parent material (2); the second annular groove (4) is provided at the corresponding position on the end face of the second parent material (2).

4. The joint structure for high-energy beam welding according to claim 1, 2, or 3, characterized in that: The exhaust channel (5) is at least one of a straight hole, a zigzag hole, and a spiral hole; The through hole is a circular or rectangular through-hole; The zigzag hole is composed of multiple circular or rectangular straight channels connected at a specific angle. The spiral hole is a spiral venting hole with constant pitch or variable pitch.

5. The joint structure for high-energy beam welding according to claim 4, characterized in that: When there are two or more exhaust channels (5), they are arranged at equal intervals along the circumference of the first parent material (1) and / or the second parent material (2).

6. The joint structure for high-energy beam welding according to claim 1, characterized in that: The groove width L of the first annular groove (3) and the second annular groove (4) is: , where d is the depth of the weld at the welding point on the welding surface after the assembly of base material one (1) and base material two (2).

7. The joint structure for high-energy beam welding according to claim 6, characterized in that: The inner sides of the groove edges of the first annular groove (3) and the second annular groove (4) are provided with chamfers that are aligned with each other.

8. The joint structure for high-energy beam welding according to claim 1, characterized in that: The radial cross-section of the annular stress relief channel is a rectangular structure, and the four corners of the rectangular structure are provided with rounded chamfers.

9. A method for processing and welding a joint structure for high-energy beam welding as described in any one of claims 1 to 8, characterized in that, Includes the following steps: Step 1: According to the preset requirements, process the parent material 1 (1) and parent material 2 (2) respectively. Step 2: Based on the maximum torque that the base material 1 (1) and base material 2 (2) can withstand, calculate the depth of the weld at the weld joint after the two are assembled, and accordingly process the first annular groove (3) and the second annular groove (4) at the corresponding positions of the weld surfaces of the base material 1 (1) and base material 2 (2). Step 3: Based on the dimensions and material properties of base material 1 (1) and base material 2 (2), determine the number, size and position of exhaust channels (5), and process the corresponding exhaust channels (5) on base material 1 (1) and / or base material 2 (2). Step 4: Assemble base material one (1) and base material two (2), and check the axial and / or radial fit of the two with a feeler gauge. If the fit meets the requirements, proceed to step 5; if the fit does not meet the requirements, scrap or rework according to the preset process requirements until the fit meets the requirements, and then proceed to step 5. Step 5: Using high-energy beam welding technology, the base material one (1) and base material two (2) are welded at the predetermined weld seam to obtain the high-energy beam welded joint structure.

10. The method for processing and welding the joint structure of high-energy beam welding according to claim 9, characterized in that: In step 4, the requirement for fit is that the axial and / or radial gap between the first base material (1) and the second base material (2) is less than or equal to 0.03 mm.

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