Friction stir welding tool head, application of friction stir welding tool head and online observation method for internal forming process of welding seam

Abstract

The invention discloses a friction stir welding tool head based on a video technology, application of the friction stir welding tool head and an online observation method for the internal forming process of a welding seam. The tool head comprises an integrally-formed stirring head and a stirring needle arranged on the lower portion of the stirring head, the stirring head is sleeved with a shaft shoulder, the stirring head and the stirring needle are made of transparent rigid materials, the melting point of the rigid materials is not lower than 900 DEG C, and a miniature lens and a miniature lamp bead of a pinhole camera are fixedly arranged in an inner cavity of the stirring needle. The method comprises the steps that in the friction stir welding process, videos or pictures obtained in real time are transmitted to a data terminal, and the internal forming process of a welding seam is observed on the data terminal. By the adoption of the scheme, the internal forming process of the welding seam in the friction stir welding process can be observed on line, the flow evolution condition of the plasticizing material in the welding seam can be monitored in real time, and the technical blank of visualization research of low-melting-point materials in the friction stir welding process is filled.

Description

Technical Field

[0001] The invention belongs to the technical field of stir friction welding, and in particular relates to a stir friction welding tool head based on video technology, an application thereof and an online observation method for the internal forming process of a weld. Background Art

[0002] The existing document CN112025074B discloses a friction stir welding device and system, which is equipped with a camera to observe the cutting and welding process; the document CN110548988A discloses a weld track automatic recognition device, in which a CCD ordinary camera is connected to the body of the friction stir welding device through a first mounting bracket, and the TOF depth of field camera is connected to the body of the friction stir welding device through a second mounting bracket. However, the friction stir welding device described above cannot observe the internal forming process of the weld online, and cannot monitor the flow evolution of the plasticized material inside the weld in real time. Summary of the invention

[0003] At least in order to solve the technical problems mentioned in the background technology, the present invention aims to provide a friction stir welding tool head based on video technology and its application and an online observation method for the internal forming process of the weld.

[0004] The present invention adopts the following technical solution.

[0005] A friction stir welding tool head comprises an integrally formed stirring head and a stirring needle arranged at the lower part of the stirring head, a shaft shoulder is sleeved on the stirring head, the stirring head and the stirring needle are made of a transparent rigid material, the melting point of the rigid material is not less than 900°C, and a micro lens and a micro lamp bead of a pinhole camera are fixedly arranged in the inner cavity of the stirring needle.

[0006] As a preferred solution, the rigid material is quartz glass.

[0007] As a preferred solution, the pinhole camera is connected to the data terminal via wireless communication.

[0008] In order to improve the stability of the hollow friction stir welding tool head of the present invention during use, a metal sleeve is provided on the outer wall of the upper middle part of the stirring head, a shock-absorbing pad is provided between the metal sleeve and the stirring head, and the outer wall of the metal sleeve is used to connect the friction stir welding spindle.

[0009] As a preferred solution, one or more micro lenses can just cover a 360° camera field of view at the same time.

[0010] In order to improve the imaging stability during the friction stir welding process, a potting glue is arranged in the inner cavity of the stirring needle and above the micro lens and the micro lamp bead.

[0011] One application of the friction stir welding tool head of the present invention is that the friction stir welding tool head is used for welding metal plates and non-metal plates with a melting point not higher than 800°C, including but not limited to aluminum alloy plates, magnesium alloy plates, and plastic plates. Another application of the friction stir welding tool head of the present invention is that the friction stir welding tool head is used for welding a model for studying the formation mechanism of a friction stir welding weld.

[0012] An online observation method for the internal forming process of a weld using a friction stir welding tool head of the present invention comprises the following steps: Step 1, turn on the power of the friction stir welding equipment, the pinhole camera and the micro lamp beads; Step 2, during the friction stir welding process, the video or picture acquired in real time is transmitted to the data terminal; Step 3: The technician observes the internal forming process of the weld on the data terminal.

[0013] Beneficial effects: By adopting the scheme of the present invention, the internal forming process of the weld during the stir friction welding process can be observed online, and the flow evolution of the plasticized material inside the weld can be monitored in real time, filling the gap in the visualization research technology of low-melting-point materials during the stir friction welding process. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a three-dimensional schematic diagram of the friction stir welding tool head in Example 1; Figure 2 Schematic diagram of the cross section of the friction stir welding tool head in Example 1; Figure 3 Schematic diagram of the cross section of the friction stir welding weld formation mechanism research model in Example 1; Figure 4 This is a top view schematic diagram of the research model of the friction stir welding weld formation mechanism in Example 1. DETAILED DESCRIPTION

[0015] The technical solution of the present invention is described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example 1

[0016] Combination Figure 1 to Figure 2As shown, a stir friction welding tool head includes an integrally formed stirring head 1 and a stirring needle 2 arranged at the lower part of the stirring head 1, a shaft shoulder 7 is sleeved on the stirring head 1, the stirring head 1 and the stirring needle 2 are made of a transparent rigid material, the melting point of the rigid material is not less than 900°C, a micro lens 3 and a micro lamp bead 4 of a pinhole camera are fixedly arranged in the inner cavity of the stirring needle 2, and the wall thickness of the stirring needle 2 is 4mm. In this embodiment, the rigid material is quartz glass; the pinhole camera is connected to a data terminal (such as a computer, a mobile phone) through wireless communication. A metal sleeve 5 is arranged on the outer wall of the upper middle part of the stirring head 1, and a shock absorbing pad 6 is sleeved between the metal sleeve 5 and the stirring head 1, and the outer wall of the metal sleeve 5 is used to connect the stir friction welding spindle. The lower end of the micro lens 3 is substantially flush with the lower end of the shaft shoulder 7, so that only one micro lens 3 is needed to cover the 360° camera field of view at the same time. A potting glue is arranged in the inner cavity of the stirring needle 2 and above the micro lens 3 and the micro lamp bead 4. Example 2

[0017] The application of the friction stir welding tool head in Example 1 is used for welding metal plates and non-metal plates with a melting point not higher than 800°C. For example, it is used for welding aluminum alloy plates with a wall thickness of 5 mm, it is used for welding aluminum alloy plates with a wall thickness of 4 mm, and it is used for welding resin plates with a wall thickness of 10 mm. During use, a stirring needle of an appropriate size can be selected according to the plate to be welded. Example 3

[0018] A method for online observation of the internal forming process of a weld seam, using the friction stir welding tool head in Example 1, comprising the following steps: Step 1, first pre-treat (grinding, cleaning and other conventional preparation processes) and clamp the two parent materials to be welded, then turn on the power of the friction stir welding equipment, the pinhole camera and the micro lamp bead 4, then adjust the stirring needle 2 to the welding starting point, and then start welding; it should be noted that during the friction stir welding process, it is necessary to always control the stirring head 1 to rotate and move forward at a constant speed, and it is best to start welding from the end side of the parent material; Step 2, during the friction stir welding process, the video or picture acquired in real time is transmitted to the data terminal; Step 3: The technician observes the internal forming process of the weld on the data terminal.

[0019] When used (such as online observation of the internal forming process of the weld), it is similar to "gastroscopy" for a fixed part, which can observe the internal forming of the weld very simply and intuitively. The scheme of the present invention can be used to observe the internal forming process of the weld during the stir friction welding process online, and can monitor the flow evolution of the plasticized material inside the weld in real time, filling the gap in the visualization research technology of low melting point materials during the stir friction welding process.

[0020] In other embodiments, multiple micro lenses 3 may be used to achieve a camera field of view that can cover 360° at the same time. Example 4

[0021] The application of the friction stir welding tool head in Example 1 is used for welding a friction stir welding weld formation mechanism research model. Figure 3 and Figure 4 As shown, the research model of the formation mechanism of the friction stir welding weld specifically includes: a frame 11, a lifting bottom plate 19 is arranged in the frame 11 (specifically, a screw lifting mechanism 16 is arranged at the bottom of the bottom plate 19, and when it is necessary to control the lifting and lowering of the bottom plate 19, the bottom plate 19 is pre-connected to the lifting rod of the screw lifting mechanism 16, and then the screw lifting mechanism 16 is controlled to work to adjust the height of the bottom plate 19), a base material model 12 is arranged in the frame 11 and on the bottom plate 19, the base material model 12 includes a plurality of layers of metal particle layers 13 of different colors stacked together, and a cover plate 15 for pressing the metal particle layer 13 is arranged on the top layer 14 of the metal particles, and a strip hole 17 is arranged on the cover plate 15 for allowing the stirring head to pass through, and the position of the strip hole 17 corresponds to the simulated weld. Among them, the metal particle layer 13 is paved with titanium alloy particles. The particles of the metal particle layer 13 are in a polygonal structure, and the particle size (size) is 0.5±0.1mm (that is, the edge length of the particles is 0.5±0.1mm). The particles with this polygonal structure can cooperate well with the stirring head, and can effectively avoid the particles from slipping during the stir friction welding process and causing the particles to not flow and shift. An adjustment mechanism 20 for adjusting the height position of the cover plate 15 and for pressing the cover plate 15 is provided on the frame 11. In this embodiment, one end of the strip hole 17 extends to the outer wall of the frame 1, so that the stirring head and the movable cover plate 21 can smoothly enter the welding area and move smoothly. The top of the movable cover plate 21 is connected to the mounting seat of the stirring head through a connecting rod. During the stir friction welding process, the stirring head and the shaft shoulder rotate synchronously, and the movable cover plate 21 moves laterally with the stirring head ( Figure 4 The hollow arrow indicates the moving direction of the stirring head, that is, the welding direction). The area around the stirring head shoulder at the top layer 14 of the metal particles is always pressed by the movable cover plate 21, and a stirring head with a shoulder outer diameter equal to the width of the strip hole 17 is selected. By adopting the scheme in this embodiment, the material flow evolution characteristics of the entire weld area can be obtained online and in real time, and the material flow evolution of the weld area can be accurately and visually characterized, which is particularly conducive to visualizing the material flow evolution at different depths of the layers, and provides visual data for the study of the formation mechanism of the stir friction welding weld.

Claims

1. A friction stir welding tool head, comprising an integrally formed stirring head (1) and a stirring needle (2) arranged at the lower part of the stirring head (1), wherein a shaft shoulder (7) is sleeved on the stirring head (1), characterized in that: The stirring head (1) and the stirring needle (2) are made of a transparent rigid material, the melting point of the rigid material is not less than 900° C. A micro lens (3) of a pinhole camera and a micro lamp bead (4) are fixedly arranged in the inner cavity of the stirring needle (2).

2. The friction stir welding tool head according to claim 1, characterized in that: The rigid material is quartz glass.

3. The friction stir welding tool head according to claim 1, characterized in that: The pinhole camera is connected to the data terminal via wireless communication.

4. The friction stir welding tool head according to claim 1, characterized in that: A metal sleeve (5) is provided on the outer wall of the upper middle portion of the stirring head (1), a shock-absorbing pad (6) is sleeved between the metal sleeve (5) and the stirring head (1), and the outer wall of the metal sleeve (5) is used to connect a stir friction welding main shaft.

5. The friction stir welding tool head according to any one of claims 1 to 5, characterized in that: One or more micro lenses (3) can just cover a 360° camera field of view at the same time.

6. The friction stir welding tool head according to claim 5, characterized in that: A potting glue is provided in the inner cavity of the stirring needle (2) and above the micro lens (3) and the micro lamp bead (4).

7. The use of the friction stir welding tool head according to any one of claims 1 to 6, characterized in that: The friction stir welding tool head is used for welding metal sheets and non-metal sheets with a melting point not higher than 800°C.

8. The use of the friction stir welding tool head according to any one of claims 1 to 6, characterized in that: The friction stir welding tool head is used for welding a friction stir welding weld formation mechanism research model.

9. A method for online observation of the internal forming process of a weld using the friction stir welding tool head according to any one of claims 1 to 6, characterized in that the steps include: Step 1, turning on the power of the friction stir welding device, the pinhole camera and the micro lamp bead (4); Step 2, during the friction stir welding process, the video or picture acquired in real time is transmitted to the data terminal; Step 3, the technician observes the internal forming process of the weld on the data terminal.

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