An underwater wet electric arc additive repair device and method

Abstract

The application discloses an underwater wet electric arc additive repair device and a repair method, and belongs to the technical field of in-situ repair of marine structures. Through the coupling effect of a magnetic field and an acoustic field, the electric arc shape and the molten pool flow in the wet electric arc additive process can be effectively and timely regulated, so that the wet electric arc additive forming precision is improved, and additive forming defects are eliminated. Good additive forming can significantly reduce the possibility of slag inclusion, stress concentration and cracks in the additive sample, and improve the performance of the additive sample, thereby solving the problem that, in the prior art, the periodic circulation of electric arc bubbles disturbs the wet repair process, and then causes the molten pool to produce unstable oscillation and rapid solidification, and affects the forming quality and forming precision of additive repair.

Description

Technical Field

[0001] This invention belongs to the field of in-situ repair technology of marine structures, and relates to underwater wet arc additive manufacturing technology, particularly to an underwater wet arc additive repair device and method with magnetic field-ultrasonic dual-field coupling assisted shape control. Background Technology

[0002] For offshore structures such as ships, vessels, and oil drilling platforms, damage and cracking are highly susceptible to occur during their service life due to additional loads and various corrosive effects, leading to serious economic losses or major safety accidents. Currently, existing underwater in-situ repair technologies mainly include three categories: wet methods, partial dry methods, and dry methods. Among these, underwater wet in-situ additive repair is the most widely used in-situ repair technology for marine structures due to its advantages of high repair efficiency and simple equipment compared to the other two. Underwater wet in-situ additive repair, also known as "underwater wet welding," involves welding without external protection measures. The welding area is completely exposed to the water environment, relying solely on the gas generated by the flux-cored wire for protection during the welding process. Current wet additive repair processes mainly include manual arc welding performed by divers holding welding rods and self-shielded flux-cored wire arc welding. The former has limitations due to low operational efficiency and restricted diver movement, while the latter, through continuous feeding of filler material and automation of repair equipment, enables continuous repair, overcoming the limitations of deep water and representing a key future development direction in this field.

[0003] Current wet arc welding repair processes using self-shielded flux-cored wire rely on the continuous generation and rising of arc bubbles in the repair area to maintain arc combustion. The periodic circulation of these arc bubbles severely disturbs the wet repair process, significantly repelling the droplet transfer process and generating strong periodic impacts on the molten pool. This leads to unstable oscillations and rapid solidification in the molten pool, potentially causing the following defects:

[0004] 1. It seriously affects the forming quality and forming accuracy of additive repair, resulting in tilting or unevenness of the additive sample surface, increased side waviness, forming defects such as humps, collapses, and slag inclusions, which leads to an increase in the additive stress concentration factor and increased crack sensitivity.

[0005] II. The rapid cooling and hydrogen-rich characteristics of the aquatic environment increase the solidification rate of the molten pool, increase the tendency of columnar crystal epitaxial growth, reduce the plasticity and toughness of additive metals, and improve the anisotropy of mechanical properties. Summary of the Invention

[0006] The purpose of this invention is to provide a novel underwater wet arc additive repair device and method. By applying an external magnetic field to adjust the melting range of the arc and the flow range of the molten pool, and by applying external ultrasound to control the flow of the molten pool to both sides through the sound pressure and acoustic flow effect, the coupling effect of the two achieves the purpose of controlling the morphology of the molten pool and the forming quality of the wet arc additive repair. This solves the problem in the prior art where the periodic circulation of arc bubbles disturbs the wet repair process, leading to unstable oscillations and rapid solidification of the molten pool, which affects the forming quality and accuracy of the additive repair.

[0007] To achieve the above objectives, the present invention provides the following solution:

[0008] This invention provides an underwater wet arc additive repair device, comprising:

[0009] An additive manufacturing apparatus includes a conductive base and a welding torch. The conductive base is used to place a test base material, and the welding torch is located above the conductive base and is used to provide a filler material to the surface of the test base material. The filler material is deposited on the surface of the test base material to form an additive sample.

[0010] A magnetic field generating device is used to apply a magnetic field to the outer periphery of the nozzle of the welding torch, so as to adjust the melting range of the electric arc and the flow range of the molten pool through the magnetic field.

[0011] An ultrasonic generator is disposed on the outer periphery of the nozzle of the welding torch and is used to apply ultrasonic waves to the molten pool of the additive sample in order to control the spreading range of the molten pool by utilizing the sound pressure and acoustic flow effects generated by the ultrasonic waves.

[0012] Optionally, it also includes a welding machine, wherein the flux-cored welding wire in the welding torch and the conductive base are respectively electrically connected to the positive and negative terminals of the power supply in the welding machine.

[0013] Optionally, it also includes a wire feeder, which is communicatively connected to the welding machine and is used to feed the flux-cored welding wire into the welding torch.

[0014] Optionally, the magnetic field generating device includes:

[0015] A ring-shaped iron core with a notch at the bottom is disposed above the conductive base and encircles the outer periphery of the welding torch, with the nozzle of the welding torch located at the notch;

[0016] A coil, wound around the side arm of the toroidal iron core, is used to connect to an external pulse power supply to generate a magnetic field around the nozzle of the welding torch when the welding torch feeds filler material into the repair position of the test base material.

[0017] Optionally, the top of the annular iron core is bent to one side, the welding torch is inserted between the two arms of the annular iron core, and is connected to the two arms of the annular iron core through an iron core clamping device; the coil is respectively provided on the two arms of the annular iron core.

[0018] Optionally, the ultrasound generating device includes:

[0019] An adjusting frame includes a horizontal connecting rod, a first vertical connecting rod, and a second vertical connecting rod. The horizontal connecting rod has a first clamping block, a second clamping block, and a third clamping block arranged sequentially at intervals along its length. Each of the three clamping blocks can slide horizontally relative to the horizontal connecting rod. The top of the first vertical connecting rod is connected to the first clamping block and can slide vertically relative to it. The top of the welding torch is connected to the second clamping block and can slide vertically relative to it. The top of the second vertical connecting rod is connected to the third clamping block and can slide vertically relative to it.

[0020] The first ultrasonic head is used to connect an external ultrasonic generator and is located on the side of the welding torch where the additive material has been deposited. The first ultrasonic head is connected to the bottom of the vertical connecting rod through an angle adjustment mechanism, which can adjust the tilt angle of the first ultrasonic head relative to the welding torch.

[0021] The second ultrasonic head is used to connect the ultrasonic generator externally and is located on the side of the welding torch where the additive material deposition is not completed. The second ultrasonic head is connected to the bottom of the vertical connecting rod II through the angle adjustment mechanism II, which can adjust the tilt angle of the second ultrasonic head relative to the welding torch.

[0022] Optionally, it also includes an image acquisition device, which is mounted on the vertical connecting rod 2 via a mounting base; the image acquisition device is used to acquire images of the additive repair area at the location to be repaired on the test parent material, and the mounting base can adjust the height and tilt angle of the image acquisition device relative to the additive repair area.

[0023] Optionally, the image acquisition device is a camera, and the mounting base is an electric pan-tilt head.

[0024] Optionally, it also includes a controller, which is communicatively connected to at least one of the image acquisition device, the magnetic field generating device, the welding torch, and the ultrasonic generating device.

[0025] This invention also proposes an underwater wet arc additive repair method. During the repair process of providing filler material to the repaired position of the test base material using a welding torch, while applying a magnetic field to the outer periphery of the nozzle of the welding torch, ultrasound is also applied to the molten pool of the additive sample formed by the deposition of filler material. The melting range of the arc and the flow range of the molten pool are adjusted by the magnetic field, and the spreading range of the molten pool is controlled by the sound pressure and acoustic flow effect generated by the ultrasound.

[0026] The present invention achieves the following technical effects compared to the prior art:

[0027] The underwater wet arc additive manufacturing repair device proposed in this invention features a novel and rational structure. It achieves real-time control of the arc melting region through the Lorentz force generated by the arc using a magnetic field, thereby adjusting the flow area and pattern of the molten pool. By employing corresponding magnetic field output modes to specifically regulate the arc melting range and molten pool flow range under different passes and constraint conditions, it helps maintain the molten pool shape and constant melt width, improving additive manufacturing accuracy. This effectively controls wet arc additive manufacturing and reduces the probability of inclusions and cracks. Simultaneously, the acoustic pressure and acoustic flow effects generated by ultrasound suppress the random flow of the molten pool, especially its spread into undeposited areas, thus inhibiting or eliminating macroscopic forming defects such as surface tilting, unevenness, lateral flow of the molten pool, and increased waviness that occur during wet arc additive manufacturing repair. The acoustic flow effect of ultrasound can also enhance convection inside the molten pool, accelerate the escape of hydrogen pores, and reduce the diffusible hydrogen content of the additive sample. The cavitation effect of ultrasound can also effectively break up coarse columnar crystals, form fine equiaxed crystals, improve the plasticity and toughness of the additive sample, reduce its anisotropy, and optimize its comprehensive mechanical properties.

[0028] The underwater wet arc additive manufacturing repair device and method proposed in this invention can effectively control the arc morphology and molten pool flow in the wet arc additive manufacturing process in real time through the coupling effect of magnetic and acoustic fields. This improves the forming accuracy of wet arc additive manufacturing, eliminates additive manufacturing defects, and effectively suppresses or counteracts the impact of arc bubbles on the molten pool and its influence on the additive manufacturing quality. Good additive manufacturing significantly reduces the possibility of inclusions, stress concentrations, and cracks inside the additive sample, improving the sample's performance. This solves the problem in existing technologies where the periodic circulation of arc bubbles disturbs the wet repair process, leading to unstable oscillations and rapid solidification in the molten pool, thus affecting the forming quality and accuracy of the additive repair. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the overall structure of the underwater wet arc additive repair device disclosed in the embodiments of the present invention;

[0031] Figure 2 This is a partial structural schematic diagram of the underwater wet arc additive repair device disclosed in an embodiment of the present invention.

[0032] The attached figures are labeled as follows:

[0033] 100. Underwater wet arc additive repair device;

[0034] 1. Welding machine; 2. Computer; 3. Wire feeder; 4. Ring core; 41. Notch; 51. Clamping block one; 52. Clamping block two; 53. Clamping block three; 6. Coil; 61. First coil; 62. Second coil; 71. Vertical connecting rod one; 72. Vertical connecting rod two; 8. Core clamping device; 91. First ultrasonic head; 92. Second ultrasonic head; 101. Angle adjustment mechanism one; 102. Angle adjustment mechanism two; 11. Additive sample; 12. Conductive base; 13. Pulse power supply; 14. Ultrasonic generator; 15. Flux-cored welding wire; 16. Welding torch; 17. Horizontal connecting rod; 18. Mounting base; 19. Image acquisition device; 20. Test base material; 21. Conductive nozzle. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] One objective of this invention is to provide a novel underwater wet arc additive repair device. This device adjusts the melting range of the arc and the flow range of the molten pool by applying an external magnetic field, and controls the flow of the molten pool to both sides by applying external ultrasonic pressure and acoustic flow effects. Through the coupling effect of these two, the device aims to control the morphology of the molten pool and the forming quality of the wet arc additive repair. This addresses the problem in the prior art where the periodic circulation of arc bubbles disturbs the wet repair process, leading to unstable oscillations and rapid solidification of the molten pool, which in turn affects the forming quality and accuracy of the additive repair.

[0037] Another objective of this invention is to provide an underwater wet arc additive repair method. This method adjusts the melting range of the arc and the flow range of the molten pool by applying an external magnetic field, and controls the flow of the molten pool to both sides by applying external ultrasonic pressure and acoustic flow effects. Through the coupling effect of these two methods, the method aims to control the morphology of the molten pool and the forming quality of the wet arc additive repair. This solves the problem in the prior art where the periodic circulation of arc bubbles disturbs the wet repair process, leading to unstable oscillations and rapid solidification of the molten pool, which affects the forming quality and accuracy of the additive repair.

[0038] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] Example 1

[0040] like Figure 1 and Figure 2 As shown, this embodiment provides an underwater wet arc additive manufacturing repair device 100, including an additive manufacturing device, a magnetic field generating device, and an ultrasonic generating device. The additive manufacturing device includes a conductive base 12 and a welding torch 16. The conductive base 12 is used to place a test base material 20. The welding torch 16 is located above the conductive base 12 and is used to provide a filler material (i.e., flux-cored wire 15) to the surface of the test base material 20. The filler material is deposited and solidified on the surface of the test base material 20 to form an additive sample 11. The magnetic field generating device is used to apply a magnetic field to the outer periphery of the nozzle of the welding torch 16 to adjust the melting range of the arc and the flow range of the molten pool. The ultrasonic generating device is disposed on the outer periphery of the nozzle of the welding torch 16 and is used to apply ultrasound to the molten pool of the additive sample 11 to control the spreading range of the molten pool by utilizing the sound pressure and acoustic flow effect generated by the ultrasound.

[0041] When the filler material is deposited in the damaged area of ​​the test parent material 20, the area where the additive sample 11 is formed is also called the "additive repair area", which can complete the in-situ additive repair of the damaged area. 。

[0042] The underwater wet arc additive manufacturing repair device 100 proposed in this technical solution, by setting up a magnetic field generator, can achieve real-time control of the arc melting area by utilizing the Lorentz force generated by the emitted magnetic field on the arc, thereby adjusting the flow area and flow pattern of the molten pool; by setting up an ultrasonic generator, the sound pressure and acoustic flow effect generated by the emitted ultrasound can be used to suppress the random flow of the molten pool, especially the spread into the undeposited area, thus suppressing or eliminating macroscopic forming defects such as surface tilting, surface unevenness, lateral flow of the molten pool, and increased waviness caused by wet arc additive manufacturing repair; this solution, based on the magnetic field-ultrasonic dual-field coupling assisted shape control, can achieve the purpose of controlling the molten pool morphology and the forming quality of wet arc additive manufacturing repair, solving the current problems of unstable molten pool flow, poor deposition layer forming quality, and low forming accuracy in underwater wet arc additive manufacturing. The aforementioned molten pool is formed in the aforementioned additive repair area. The molten pool is an inevitable and conventional means in the implementation of underwater wet arc additive manufacturing technology, and its formation principle will not be elaborated here.

[0043] In this embodiment, a magnetic field generating device preferably applies a magnetic field to the bottom end of the flux-cored welding wire 15 inside the welding torch 16.

[0044] Example 2

[0045] Based on Embodiment 1, this embodiment also includes a welding machine 1 in the underwater wet arc additive repair device 100. The flux-cored wire 15 and the conductive base 12 in the welding torch 16 are electrically connected to the positive and negative terminals of the power supply in the welding machine 1, respectively.

[0046] Furthermore, the underwater wet arc additive repair device 100 is also equipped with a wire feeder 3, which is connected in communication with the aforementioned welding machine 1. The wire feeder 3 is used to feed the flux-cored welding wire 15 into the welding torch 16.

[0047] The welding machine 1, wire feeder 3, flux-cored welding wire 15 and welding torch 16 mentioned above are all existing structures, and their specific structures and working principles will not be described in detail here.

[0048] Example 3

[0049] Based on Embodiment 1 or Embodiment 2, the magnetic field generating device in this embodiment includes a coil 6 and an annular iron core 4 with a notch 41 at the bottom, such as... Figure 1 and Figure 2As shown, the annular iron core 4 is positioned above the conductive base 12 and encircles the outer periphery of the welding torch 16, with the nozzle of the welding torch 16 located at the notch 41. A coil 6 is wound around the side arm of the annular iron core 4. The coil 6 is used to connect to an external pulse power supply 13 to generate a uniform or alternating magnetic field around the nozzle of the welding torch 16 when the welding torch 16 provides filler material (i.e., flux-cored wire 15) to the repaired position of the test base material 20. This uniform or alternating magnetic field is used to utilize the Lorentz force generated by the arc to achieve real-time control of the arc melting area, thereby adjusting the flow area and flow pattern of the molten pool. Generally, it is preferable that the plane of the annular iron core 4 is parallel to the additive direction, the direction of the magnetic field generated in the additive repair area is parallel to the additive direction, and the magnetic field mainly acts on the end of the flux-cored wire 15 extending from the bottom of the welding torch 16. By employing different magnetic field output modes, the arc melting range and molten pool flow range under different passes and constraint conditions can be specifically controlled, thereby achieving effective control of wet arc additive manufacturing and reducing the probability of slag inclusions and crack defects.

[0050] In this embodiment, the annular iron core 4 is U-shaped and has a symmetrical structure. Considering that the welding torch 16 is generally vertically arranged, in order to avoid positional interference between the welding torch 16 and the annular iron core 4, it is preferable to bend the top of the annular iron core 4 (i.e., the end opposite to the notch 41) to one side, so that the welding torch 16 can avoid the top of the annular iron core 4 and be inserted between the two arms of the annular iron core 4, such as... Figure 1 and Figure 2 As shown.

[0051] As a further preferred embodiment, the welding torch 16 can be connected to the two side arms of the annular iron core 4 via the core clamping device 8, thereby connecting the welding torch 16 and the annular iron core 4 into a single unit, facilitating synchronous position adjustment of the welding torch 16 and the annular iron core 4. The aforementioned core clamping device 8 is preferably a clamping block, comprising a first clamping block and a second clamping block. Both the first and second clamping blocks are provided with cavities for accommodating the welding torch 16 and the two side arms of the annular iron core 4. After the first and second clamping blocks are mated, they are fixed by bolts, thereby clamping and fixing the welding torch 16 and the two side arms of the annular iron core 4.

[0052] As a further preferred option, coils 6 are respectively provided on both sides of the toroidal core 4, specifically, as follows: Figure 2 As shown, for distinction, the coil 6 located on one side arm of the toroidal core 4 is referred to as "first coil 61", and the coil 6 located on the other side arm of the toroidal core 4 is referred to as "second coil 62". The first coil 61 and the second coil 62 adopt the same coil structure and are both electrically connected to the pulse power supply 13.

[0053] Example 4

[0054] Based on Embodiment 3, this embodiment specifically proposes an ultrasonic generating device, which includes an adjustment frame, a first ultrasonic head 91, and a second ultrasonic head 92, wherein, as shown... Figure 1 As shown, the adjustment frame includes a horizontal connecting rod 17, a vertical connecting rod 1 71, and a vertical connecting rod 2 72. The horizontal connecting rod 17 is horizontally arranged and generally parallel to the conductive base 12. Clamping blocks 1 51, 2 52, and 3 53 are arranged sequentially and at intervals along the length of the horizontal connecting rod 17. Clamping blocks 1 51, 2 52, and 3 53 can all slide horizontally relative to the horizontal connecting rod 17 to adjust the position of clamping blocks 1 51, 2 52, and 3 53 on the horizontal connecting rod 17, respectively. The top of vertical connecting rod 71 is connected to clamping block 51 and can slide vertically relative to clamping block 51; the top of welding torch 16 is connected to clamping block 52 and can slide vertically relative to clamping block 52; the top of vertical connecting rod 72 is connected to clamping block 53 and can slide vertically relative to clamping block 53; the first ultrasonic head 91 is used to connect an external ultrasonic generator 14 and is located on the side of welding torch 16 where additive deposition has been completed. The first ultrasonic head 91 is adjustable in angle. Mechanism 101 is connected to the bottom of vertical link 71. The angle adjustment mechanism 101 can adjust the tilt angle of the first ultrasonic head 91 relative to the welding gun 16. The second ultrasonic head 92 is used to connect an external ultrasonic generator 14 and is located on the side of the welding gun 16 where the additive material has not been deposited. The second ultrasonic head 92 is connected to the bottom of vertical link 72 through angle adjustment mechanism 2102. The angle adjustment mechanism 2102 can adjust the tilt angle of the second ultrasonic head 92 relative to the welding gun 16.

[0055] Specifically, in the above scheme, the length extension direction of the horizontal connecting rod 17 can be... Figure 1 and Figure 2 As shown in the Y-direction, both vertical connecting rod 71 and vertical connecting rod 72 are perpendicular to the horizontal connecting rod 17, that is, vertical connecting rod 71 and vertical connecting rod 72 can be... Figure 1 and Figure 2The Z-direction is shown. The direction perpendicular to both the Y and Z directions is the X-direction. In this embodiment, the first ultrasonic head 91 is connected to the horizontal connecting rod 17 via an angle adjustment mechanism 101, a vertical connecting rod 71, and a clamping block 51. By adjusting the clamping block 51 horizontally on the horizontal connecting rod 17, adjusting the vertical connecting rod 71 vertically relative to the clamping block 51, and adjusting the angle of the first ultrasonic head 91 via the angle adjustment mechanism 101, the horizontal, vertical, and tilt angle adjustments of the first ultrasonic head 91 can be achieved. The horizontal adjustment of clamping block 51 on horizontal connecting rod 17 can be manual. For example, clamping block 51 can be sleeved on horizontal connecting rod 17. After manually sliding clamping block 51 to adjust its horizontal position, clamping block 51 can be fixed in the corresponding position on horizontal connecting rod 17 by screwing a set screw into the side wall of clamping block 51 and tightening the set screw against the side arm of horizontal connecting rod 17. When adjustment is needed, the set screw can be loosened. The horizontal adjustment of clamping block 51 on horizontal connecting rod 17 can also be electric. For example, clamping block 51 can be sleeved on horizontal connecting rod 17, and a lead screw structure parallel to horizontal connecting rod 17 can be installed through clamping block 51. The position adjustment and position locking of clamping block 51 on horizontal connecting rod 17 can be achieved by driving the lead screw structure to rotate through a motor. Correspondingly, the vertical adjustment of the vertical connecting rod 71 relative to the clamping block 51 can refer to the adjustment method of the relative position of the clamping block 51 and the horizontal connecting rod 17. For example, the clamping block 51 can be fitted onto the vertical connecting rod 71 (the vertical connecting rod 71 and the horizontal connecting rod 17 are respectively inserted into two different holes of the clamping block 51, and the axes of the two holes are perpendicular). After manually raising and lowering the vertical connecting rod 71 and adjusting its vertical position relative to the clamping block 51 to the correct position, a set screw can be screwed into the side wall of the clamping block 51 to tighten the vertical connecting rod 71. The vertical connecting rod 71 is fixed inside the clamping block 51 via a side arm mechanism. Adjustment is achieved by loosening the set screw. Furthermore, the vertical adjustment of the vertical connecting rod 71 relative to the clamping block 51 is also electrically adjustable. The clamping block 51 is fitted onto the vertical connecting rod 71, and an electric telescopic rod or electric cylinder can be connected to it. This allows the electric telescopic rod or electric cylinder to drive the vertical connecting rod 71 to rise or fall relative to the clamping block 51, maintaining its position after adjustment. As for the aforementioned angle adjustment mechanism 101, it primarily drives the rotation of the first ultrasonic head 91. Figure 1 As shown, the angle adjustment mechanism 101 can at least drive the angle adjustment mechanism 101 to rotate around an axis parallel to the X direction. The angle adjustment mechanism 101 can be an existing universal adjustment frame, a three-dimensional electric slide, a two-dimensional electric slide, or a simple hinge seat, etc., which will not be described in detail here.

[0056] In this embodiment, the second ultrasonic head 92 is connected to the horizontal connecting rod 17 via an angle adjustment mechanism 102, a vertical connecting rod 72, and a clamping block 53. The second ultrasonic head 92 can be adjusted horizontally on the horizontal connecting rod 17 by adjusting the clamping block 53 horizontally, vertically relative to the clamping block 53 by adjusting the vertical connecting rod 72, and angle by adjusting the angle of the second ultrasonic head 92 via the angle adjustment mechanism 102. This allows for horizontal, vertical, and tilt angle adjustments of the second ultrasonic head 92. The specific connection and adjustment methods of the angle adjustment mechanism 102, the vertical connecting rod 72, the clamping block 53, and the horizontal connecting rod 17 are exactly the same as those of the angle adjustment mechanism 101, the vertical connecting rod 71, the clamping block 51, and the horizontal connecting rod 17 corresponding to the first ultrasonic head 91, and will not be described again here.

[0057] In this embodiment, the welding torch 16 is connected to the horizontal connecting rod 17 via the second clamping block 52. The horizontal and vertical adjustments of the welding torch 16 can be achieved by adjusting the second clamping block 52 horizontally on the horizontal connecting rod 17 and by adjusting the welding torch 16 vertically relative to the second clamping block 52. The specific connection and adjustment methods of the welding torch 16, the second clamping block 52, and the horizontal connecting rod 17 are exactly the same as those between the vertical connecting rod 71, the first clamping block 51, and the horizontal connecting rod 17 corresponding to the first ultrasonic head 91, and will not be repeated here.

[0058] In this embodiment, as Figure 1 As shown, the first ultrasonic head 91 and the second ultrasonic head 92 are located on both sides of the welding torch 16, and their positions can be adjusted independently. In actual operation, for single-pass multi-layer wall samples in arc additive manufacturing, the first ultrasonic head 91 and the second ultrasonic head 92 will be symmetrically distributed. For certain positions in multi-layer multi-pass additive manufacturing processes, the first ultrasonic head 91 and the second ultrasonic head 92 may be at the same height, or one of them may be higher than the other; adjustments can be made according to actual needs.

[0059] Example 5

[0060] Based on Embodiment 4, an image acquisition device 19 is also provided in the underwater wet arc additive repair device 100. The image acquisition device 19 is mounted on the vertical connecting rod 72 via a mounting base 18. The image acquisition device 19 is used to acquire images of the additive repair area on the test base material 20 at the location to be repaired. The mounting base 18 can adjust the tilt angle of the image acquisition device 19 relative to the additive repair area, and the mounting position of the mounting base 18 on the vertical connecting rod 72 is adjustable. By adjusting the mounting height of the mounting base 18 on the vertical connecting rod 72, the height of the image acquisition device 19 relative to the additive repair area can be adjusted.

[0061] In the above scheme of this embodiment, the image acquisition device 19 is preferably a camera, and the mounting base 18 is an electric pan-tilt head. The mounting position of the electric pan-tilt head on the vertical connecting rod 72 is adjustable (for example, by tightening and loosening the screw). The electric pan-tilt head is a prior art technology, which can adjust the camera horizontally, vertically and rotatably to meet the camera's multi-angle image acquisition needs for the additive repair area. The specific structure and working principle of the electric pan-tilt head will not be described in detail here.

[0062] Furthermore, the image acquisition device 19 described above is preferably a high-speed camera.

[0063] Example 6

[0064] Based on Embodiment 5, a controller is also provided in the underwater wet arc additive repair device 100. This controller can be a computer 2, which is communicatively connected to at least one of the image acquisition device 19, the magnetic field generating device, the welding torch 16, and the ultrasonic generating device. Preferably, the computer 2 is communicatively connected to all electrical components in the entire underwater wet arc additive repair device 100 to achieve automated control of the entire device, thus automating the additive repair process and improving repair accuracy and quality.

[0065] The working process and working principle of the underwater wet arc additive repair device 100 disclosed in this embodiment will be specifically explained below. The image acquisition device 19 employs a high-speed camera.

[0066] like Figure 1 and Figure 2As shown, in the underwater wet arc additive manufacturing repair device 100, the top of the welding torch 16 is connected to the horizontal connecting rod 17 via a clamping block 2 52, and the horizontal connecting rod 17 is perpendicular to the forward direction of the welding torch 16. A clamping block 1 51 on the horizontal connecting rod 17 is located to the left of clamping block 2 52, and a clamping block 3 53 is located to the right of clamping block 2 52. A vertical connecting rod 1 71 is connected to the horizontal connecting rod 17 via clamping block 1 51, and a vertical connecting rod 2 72 is connected to the horizontal connecting rod 17 via clamping block 3 53. An angle adjustment mechanism 101 is provided at the bottom of vertical connecting rod 1 71, and an angle adjustment mechanism 2 102 is provided at the bottom of vertical connecting rod 2 72. A first ultrasonic head 91 is connected to vertical connecting rod 1 71 via angle adjustment mechanism 101, and a second ultrasonic head 92 is connected to vertical connecting rod 2 72 via angle adjustment mechanism 2 102. The first ultrasonic head 91 is located on the side where the additive material has been deposited, and the second ultrasonic head 92 is located on the side where the additive material has not been deposited. This mechanism allows for horizontal, vertical, and angular displacement of the first and second ultrasonic heads 91 and 92 in the YZ plane. A mounting base 18 is provided between the clamping block 53 of the vertical connecting rod 72 and the second ultrasonic head 92. A high-speed camera is connected to the vertical connecting rod 72 via the mounting base 18. This mechanism allows for horizontal, vertical, and angular displacement of the high-speed camera in the YZ plane, enabling the high-speed camera to continuously and effectively monitor the additive repair area. The middle of the welding torch 16 is connected to the two arms of the annular iron core 4 via the iron core clamping device 8. The top of the annular iron core 4 is bent in the Y direction to avoid conflict with the welding torch 16. From the XZ plane, the first coil 61 and the second coil 62 are respectively arranged in the middle of the two arms of the toroidal core 4. The first coil 61 and the second coil 62 are arranged symmetrically. The number of coils on the core can be appropriately increased according to the required magnetic field strength. By adjusting the relative vertical position of the toroidal core 4 and the welding torch 16, the notch 41 of the toroidal core 4 is always aligned with the bottom end of the flux-cored wire 15. The bottom of the welding torch 16 is connected to the conductive nozzle 21 by a thread. The flux-cored wire 15 is threaded through the welding torch 16 and the conductive nozzle 21 to provide filling material for the additive repair area, so that the additive sample 11 is deposited on the surface of the area to be repaired of the test base material 20. For the peripheral devices, the computer 1 is connected to the high-speed camera. The two positive and negative electrodes of the welding machine 1 are connected to the flux-cored wire 15 and the conductive base 12, respectively. The welding machine 1 is also connected to the wire feeder 3 via a control line. The wire feeder 3 is connected to the welding machine 1 via a control line and provides filling material for the additive process. The pulse power supply 13 is connected to the first coil 61 and the second coil 62. The ultrasonic generator 14 is connected to the first ultrasonic head 91 and the second ultrasonic head 92 respectively.

[0067] During installation, the test base material 20 is first fixed on the conductive base 12, and the height of the welding torch 16 is adjusted according to the required extension (i.e., the distance between the bottom of the conductive tip 21 of the welding torch and the test base material 20, generally 12mm to 20mm). A horizontal connecting rod 17 is installed via clamping block 2 52, followed by a vertical connecting rod 71, an angle adjustment mechanism 101, and a first ultrasonic head 91 via clamping block 1 51. A vertical connecting rod 72, an angle adjustment mechanism 102, a second ultrasonic head 92, a mounting base 18, and a high-speed camera are installed via clamping block 3 53. By adjusting the position and angle of the above devices, the first ultrasonic head 91, the second ultrasonic head 92, and the high-speed camera are aligned with the molten pool of the additive repair area. The distance between the end of the ultrasonic head and the molten pool is generally maintained between 10mm and 100mm. The angles of the first ultrasonic head 91 and the second ultrasonic head 92 are determined according to the differences in the constraint conditions of the deposition passes. The annular iron core 4 is fixed to the welding torch 16 by the iron core clamping device 8, and the notch 41 of the annular iron core 4 is aligned with the lower end of the flux-cored welding wire 15. The positive terminal of the power output of the welding machine 1 is connected to the flux-cored welding wire 15, and the negative terminal is connected to the conductive base 12. It is connected to the wire feeder 3 through the control line. The wire feeder 3 feeds the flux-cored welding wire 15 into the welding torch 16 through its push-pull wire device. The wire feeding speed can be adjusted by either the welding machine 1 or the wire feeder 3. The computer 1 is connected to the high-speed camera. The computer 1 can adjust the shooting parameters of the high-speed camera, including resolution, frame rate, aperture, focal length, and trigger mode, and at the same time receive the real-time molten pool image transmitted back by the high-speed camera. The pulse power supply 13 is connected to the first coil 61 and the second coil 62. The pulse power supply 13 provides the first coil 61 and the second coil 62 with current inputs of different frequencies and power, so that the first coil 61 and the second coil 62 can generate uniform magnetic fields of different intensities or alternating magnetic fields of different intensities and frequencies. The ultrasonic generator 14 is connected to the first ultrasonic head 91 and the second ultrasonic head 92 to provide ultrasonic inputs of different frequencies and powers to the ultrasonic heads.

[0068] After completing the above installation, first turn on computer 1 and the high-speed camera, and adjust the high-speed camera's shooting parameters. Turn on pulse power supply 13, select a suitable power output mode and output power, turn on ultrasonic generator 14, and select appropriate angles and power for the first ultrasonic head 91 and the second ultrasonic head 92 respectively. Turn on welding machine 1, select appropriate voltage and wire feeding speed, and turn on wire feeder 3 to begin additive repair work. After the repair work starts, dynamically adjust the output of pulse power supply 13 and ultrasonic generator 14 according to the images transmitted back by the high-speed camera to achieve real-time monitoring and control of the molten pool morphology. The power output mode and output power selection of pulse power supply 13 are as follows: When performing single-pass deposition, an alternating current output mode with equal positive and negative half-waves can be selected. By generating an alternating magnetic field, an alternating Lorentz force is generated on the arc to expand the melting range of the arc and improve the melting width and spreading effect of the single-pass deposition layer. When performing multi-layer deposition, depending on the different confinement conditions of the deposition passes, the same output mode as single-pass deposition can be selected. Alternatively, an alternating current with unequal positive and negative half-waves can be selected to generate an alternating magnetic field, or a DC current can be selected to generate a constant magnetic field. The Lorentz force is used to enhance the melting effect of the arc on one side of the previous deposition layer and reduce the spreading of the melt pool to the undeposited side. The real-time dynamic adjustment of the pulse power supply 13 in the multi-layer, multi-pass additive manufacturing process is as follows: when the molten pool spreads too widely and shifts towards the undeposited area, the proportion or intensity of the magnetic field in the negative X direction is increased to enhance the melting effect of the arc on the previous deposited layer; conversely, when the molten pool spreads too widely and shifts towards the side of the previous deposited layer, the proportion or intensity of the magnetic field in the positive X direction is increased to enhance the melting effect of the arc on the undeposited side. The selection of the angle and power of the ultrasonic generator 14, the first ultrasonic head 91, and the second ultrasonic head 92 is as follows: When performing single-layer multi-pass wall additive manufacturing, the first ultrasonic head 91 and the second ultrasonic head 92 are symmetrically arranged about the welding torch 16, with an angle approximately horizontal. The sound pressure and acoustic flow effect generated by the ultrasonic head can suppress the unstable lateral flow generated during the additive manufacturing process to the greatest extent. When performing multi-layer multi-pass deposition, the angle of the first ultrasonic head 91 is approximately in the direction of the angle bisector of the fourth quadrant, and the second ultrasonic head 92 is approximately horizontal. The sound pressure and acoustic flow effect generated by the second ultrasonic head 92 can suppress the flow of the molten pool to the undeposited side, while the first ultrasonic head 91 can control the height of the molten pool to avoid the generation of hump defects. The real-time dynamic adjustment of the ultrasonic generator 15 in the multi-layer, multi-pass additive manufacturing process is as follows: when the molten pool spreading range is too large, the output power of the second ultrasonic head 92 is increased and the output power of the first ultrasonic head 91 is decreased to inhibit the spreading of the molten pool to the undeposited side; conversely, when the molten pool spreading range is too small, the output power of the second ultrasonic head 92 is decreased and the output power of the first ultrasonic head 91 is increased to promote the spreading of the molten pool to the undeposited side.Under the combined effects of magnetic field and ultrasound, the flow range of the molten pool is precisely controlled by the magnetic field, and the spreading morphology is strictly regulated by the ultrasound. This allows for dynamic adjustment of the molten pool morphology in each deposition pass, improving the forming quality and accuracy of additive repair. Furthermore, the acoustic flow effect of ultrasound promotes convection within the molten pool, and the cavitation effect generates bubbles that break down coarse columnar crystals, refining the grains and improving the performance of wet arc additive manufacturing.

[0069] Therefore, the underwater wet arc additive repair device 100 proposed in this technical solution is essentially an adjustable magnetic field-ultrasonic dual-field coupling assisted shape control underwater wet arc additive repair device, and its specific beneficial effects are as follows:

[0070] (1) The underwater wet arc additive repair device 100 achieves real-time control of the arc melting area based on the Lorentz force generated by the magnetic field on the arc, thereby adjusting the flow area and flow pattern of the molten pool. By adopting the corresponding magnetic field output mode, the arc melting range and molten pool flow range under different passes and different constraint conditions are targeted and controlled, which helps to maintain the shape of the molten pool, maintain a constant melt width, improve the accuracy of additive forming, and thus effectively control the wet arc additive forming process, reduce the probability of inclusions and cracks, and at the same time suppress or eliminate macroscopic forming defects such as surface tilting, surface unevenness, lateral flow of the molten pool, and increased waviness caused by wet arc additive repair.

[0071] (2) The underwater wet arc additive manufacturing repair device 100 suppresses the random flow of the molten pool based on the sound pressure and acoustic flow effect generated by ultrasound, especially the spreading into the undeposited area. This suppresses or eliminates macroscopic forming defects such as surface tilting, uneven surface, lateral flow of the molten pool, and increased waviness caused by wet arc additive manufacturing repair. At the same time, the generation of ultrasound helps to maintain the shape of the molten pool and the constant melt width, thereby effectively controlling the wet arc additive manufacturing process, reducing the probability of inclusions and cracks, and improving the accuracy of additive manufacturing.

[0072] (3) The underwater wet electric arc additive repair device 100 monitors the molten pool in real time based on a high-speed camera, and dynamically adjusts the pulse arc output and ultrasonic generator output in real time to maintain the shape of the molten pool, maintain the constant molten width, and improve the accuracy of additive forming. In this way, it can effectively control the wet electric arc additive forming and reduce the probability of slag inclusions and crack defects. At the same time, it can suppress or eliminate macroscopic forming defects such as surface tilt, surface unevenness, lateral flow of the molten pool, and increased waviness caused by wet electric arc additive repair.

[0073] (4) The underwater wet arc additive repair device 100 uses the ultrasonic acoustic flow effect to stir the molten pool, accelerate the escape of hydrogen pores, and the ultrasonic cavitation effect can break the coarse columnar crystals generated during the solidification of the molten pool, effectively refine the grains in the wet arc additive process, improve the plasticity and toughness of the additive sample, reduce its anisotropy, and improve the comprehensive mechanical properties of the additive sample.

[0074] Example 7

[0075] This embodiment proposes an underwater wet arc additive manufacturing repair method. During the process of providing filler material to the surface of the test base material 20 using a welding torch 16, a magnetic field is applied to the outer periphery of the nozzle of the welding torch 16, while simultaneously applying ultrasound to the molten pool of the additive sample 11 formed by the deposition of the filler material. This allows for the adjustment of the arc melting range and the molten pool flow range through the magnetic field, utilizing the sound pressure and acoustic flow effects generated by the ultrasound to control the molten pool spreading range. This method achieves real-time control of the arc melting region through the Lorentz force generated by the magnetic field on the arc, thereby adjusting the molten pool flow region and flow pattern. By employing corresponding magnetic field output modes to specifically regulate the arc melting range and molten pool flow range under different passes and constraint conditions, it helps maintain the molten pool shape, maintain a constant melt width, improve additive manufacturing accuracy, and thus effectively control wet arc additive manufacturing, reducing the probability of inclusions and crack defects. Simultaneously, the acoustic pressure and acoustic flow effects generated by ultrasound inhibit the random flow of the molten pool, especially its spread into undeposited areas. This helps to suppress or eliminate macroscopic forming defects such as surface tilting, unevenness, lateral flow of the molten pool, and increased waviness caused by wet arc additive manufacturing. The acoustic flow effect of ultrasound also enhances convection within the molten pool, accelerates the escape of hydrogen pores, and reduces the diffusible hydrogen content of the additive sample. Furthermore, the cavitation effect of ultrasound effectively breaks down coarse columnar crystals, forming fine equiaxed crystals, improving the plasticity and toughness of the additive sample, reducing its anisotropy, and optimizing its overall mechanical properties.

[0076] The aforementioned underwater wet arc additive manufacturing repair method can be implemented using the underwater wet arc additive manufacturing repair device 100 disclosed in any one of Examples 1 to 6. This underwater wet arc additive manufacturing repair method, through the coupling effect of magnetic and acoustic fields, can effectively control the arc morphology and molten pool flow during the wet arc additive manufacturing process in real time, thereby improving the forming accuracy of wet arc additive manufacturing and eliminating additive manufacturing defects. Simultaneously, it can effectively suppress or counteract the impact of arc bubbles on the molten pool and their influence on the additive manufacturing quality. Good additive manufacturing can significantly reduce the possibility of inclusions, stress concentrations, and cracks inside the additive sample, thus improving the performance of the additive sample.

[0077] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An underwater wet arc additive repair device, characterized in that, include: An additive manufacturing apparatus includes a conductive base and a welding torch. The conductive base is used to place a test base material, and the welding torch is located above the conductive base and is used to provide a filler material to the surface of the test base material. The filler material is deposited on the surface of the test base material to form an additive sample. A magnetic field generating device is used to apply a magnetic field to the outer periphery of the nozzle of the welding torch, so as to adjust the melting range of the electric arc and the flow range of the molten pool through the magnetic field. An ultrasonic generator, disposed around the nozzle of the welding torch, is used to apply ultrasound to the molten pool of the additive sample to control the spread of the molten pool using the sound pressure and acoustic flow effects generated by the ultrasound. The ultrasonic generator includes an adjustment frame, a first ultrasonic head, and a second ultrasonic head. The adjustment frame includes a horizontal connecting rod, a first vertical connecting rod, and a second vertical connecting rod. Clamping blocks one, two, and three are sequentially spaced along the length of the horizontal connecting rod, and all three clamping blocks can slide horizontally relative to the horizontal connecting rod. The top of the first vertical connecting rod is connected to the first clamping block and can slide vertically relative to it. The top of the welding torch is connected to the second clamping block and can slide vertically relative to it. The second clamping block slides vertically; the top of the second vertical connecting rod is connected to the third clamping block and can slide vertically relative to the third clamping block; the first ultrasonic head is used to connect an external ultrasonic generator and is located on the side of the welding torch where additive material deposition has been completed; the first ultrasonic head is connected to the bottom of the first vertical connecting rod through an angle adjustment mechanism, which can adjust the tilt angle of the first ultrasonic head relative to the welding torch; the second ultrasonic head is used to connect an external ultrasonic generator and is located on the side of the welding torch where additive material deposition has not been completed; the second ultrasonic head is connected to the bottom of the second vertical connecting rod through an angle adjustment mechanism, which can adjust the tilt angle of the second ultrasonic head relative to the welding torch.

2. The underwater wet arc additive repair device according to claim 1, characterized in that, It also includes a welding machine, wherein the flux-cored welding wire in the welding torch and the conductive base are respectively electrically connected to the positive and negative terminals of the power supply in the welding machine.

3. The underwater wet arc additive repair device according to claim 2, characterized in that, It also includes a wire feeder, which is communicatively connected to the welding machine and is used to feed the flux-cored welding wire into the welding torch.

4. The underwater wet arc additive repair device according to any one of claims 1 to 3, characterized in that, The magnetic field generating device includes: A ring-shaped iron core with a notch at the bottom is disposed above the conductive base and encircles the outer periphery of the welding torch, with the nozzle of the welding torch located at the notch; A coil, wound around the side arm of the toroidal iron core, is used to connect to an external pulse power supply to generate a magnetic field around the nozzle of the welding torch when the welding torch feeds filler material into the repair position of the test base material.

5. The underwater wet arc additive repair device according to claim 4, characterized in that, The top of the annular iron core is bent to one side, and the welding torch is inserted between the two arms of the annular iron core and connected to the two arms of the annular iron core through the iron core clamping device; the coils are respectively provided on the two arms of the annular iron core.

6. The underwater wet arc additive repair device according to claim 1, characterized in that, It also includes an image acquisition device, which is mounted on the vertical connecting rod 2 via a mounting base; the image acquisition device is used to acquire images of the additive repair area at the location to be repaired on the test parent material, and the mounting base can adjust the height and tilt angle of the image acquisition device relative to the additive repair area.

7. The underwater wet arc additive repair device according to claim 6, characterized in that, The image acquisition device is a camera, and the mounting base is an electric pan-tilt head.

8. The underwater wet arc additive repair device according to claim 6, characterized in that, It also includes a controller, which is communicatively connected to at least one of the image acquisition device, the magnetic field generating device, the welding torch, and the ultrasonic generating device.

9. A method for underwater wet arc additive repair implemented using the underwater wet arc additive repair device according to any one of claims 1 to 8, characterized in that, During the repair process of applying filler material to the repaired position of the test base material using a welding torch, while applying a magnetic field to the outer periphery of the nozzle of the welding torch, ultrasound is also applied to the molten pool of the additive sample formed by the deposition of filler material, so as to adjust the melting range of the arc and the flow range of the molten pool through the magnetic field, and control the spreading range of the molten pool by the sound pressure and acoustic flow effect generated by the ultrasound.

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