Ultrasonic in-situ auxiliary laser cladding device and use method

Abstract

The invention discloses an ultrasonic in-situ auxiliary laser cladding device and a using method. The ultrasonic in-situ auxiliary laser cladding device comprises a laser head and an electronic computer, and the electronic computer controls a laser cladding manufacturing module and an ultrasonic module. The laser head, the ultrasonic vibration device and the wire feeding nozzle are rigidly connected through the coaxial clamp, seamless switching of powder feeding / wire filling cladding modes is achieved, the problem that in the prior art, a tungsten wire independently stretches into a molten pool, and consequently path interference is caused is solved, and the large-area cladding requirement of workpieces with complex curved surfaces is particularly met; the ultrasonic frequency, the wire feeding speed and laser parameters are integrally controlled through an electronic computer, so that an ultrasonic focus tracks the position of a molten pool in real time, and the problem of uneven ultrasonic action caused by the size of a base body in large workpiece machining is solved; the ultrasonic water cooling device and the cooler are matched to guarantee continuous and stable operation of the ultrasonic vibration device in a high-temperature environment, and the risk of high-temperature breakage of tungsten filaments in the prior art is avoided.

Description

Technical Field

[0001] The present invention relates to a laser cladding device, in particular to an ultrasonic in-situ assisted laser cladding device and a use method, belonging to the technical field of laser cladding. Background Art

[0002] Laser cladding is an advanced surface modification and repair technology that uses a laser beam as a heat source to irradiate the substrate and alloy powder, allowing the melted alloy powder to form a certain degree of metallurgical bonding with the substrate, ultimately obtaining a cladding coating with better material properties. It can be used to repair and remanufacture surface-damaged parts.

[0003] Wire-filled laser cladding is a new area of ​​laser cladding, replacing powdered materials with wire. Compared to powder-fed laser cladding, it offers higher material utilization, better stability, and minimal impact on equipment, and holds great promise.

[0004] Laser cladding technology is widely used in surface strengthening and repair of parts due to its advantages such as high-speed heating and cooling, strong metallurgical bonding, and small heat-affected zone. However, during the cladding process, it is easy for the cladding layer to have coarse grains, residual stress concentration, and crack defects due to differences in the thermal expansion coefficient of the materials, element segregation, and other problems. In order to improve the above problems, the existing technology introduces ultrasonic auxiliary means to refine the grains and suppress cracks through cavitation effect and acoustic streaming. At present, there are two main technical routes for ultrasonic action: one is the substrate conduction type (such as CN105714284A), in which the ultrasonic transmitting end contacts the back of the workpiece substrate and acts on the cladding layer through solid conduction, but this method is prone to uneven intensity of action on large or complex workpieces ( Figure 1(Schematic diagram of conventional ultrasonic-assisted laser cladding) and requires high-power ultrasonic equipment. The second method is non-contact air conduction (e.g., CN114645270A), where ultrasonic waves are applied to the molten pool through air. However, these methods suffer from inherent drawbacks such as severe energy loss (low air acoustic impedance leads to reflection / refraction losses), susceptibility to interference from ambient dust / mist, and low precision, significantly impacting the quality and consistency of the cladding layer. Publication No. CN117926244A discloses a highly efficient and precise contact-type ultrasonic-assisted laser cladding device and method. This method proposes a contact-based conduction scheme, using a tungsten wire to directly guide ultrasonic waves from the transmitter into the molten pool to reduce energy loss. However, this device requires the tungsten wire to be independently extended into the molten pool, making it less adaptable to the cladding head's trajectory. Furthermore, in wire-feed cladding mode, it is difficult to coordinate the wire feed angle and ultrasonic focus position. Furthermore, existing technologies have not effectively addressed the challenge of coordinating wire positioning accuracy and ultrasonic energy focusing during wire-feed cladding. Consequently, when applied to complex curved surfaces or large workpieces, the bottlenecks of ultrasonic action zone drift and insufficient cladding layer uniformity persist. Therefore, it is urgent to develop an efficient auxiliary device that can realize the precise in-situ application of ultrasonic waves, adapt to multi-mode cladding processes (powder feeding / wire filling), and is not affected by the workpiece size and environment. Summary of the Invention

[0005] The purpose of the present invention is to provide an ultrasonic in-situ assisted laser cladding device and a method of use in order to solve at least one of the above technical problems.

[0006] The present invention achieves the above-mentioned object through the following technical solutions: an ultrasonic in-situ assisted laser cladding device, comprising a laser head and an electronic computer, wherein the electronic computer controls a laser cladding manufacturing module and an ultrasonic module, a workbench is provided below the laser head, a workpiece is placed on the workbench, and the workpiece is placed on the workbench for cladding; The laser cladding manufacturing module includes a continuous laser and a movable frame. The continuous laser is connected to the laser head through a continuous laser optical fiber. The laser head is fixed on the movable frame. The ultrasonic module includes an ultrasonic vibration device and an ultrasonic frequency generator. The ultrasonic frequency generator is connected to an electronic computer and an ultrasonic vibration device respectively. The ultrasonic vibration device is connected to one side of the laser head. The other side of the laser head is connected to a wire feeding nozzle. The wire feeding nozzle sprays out metal wire. The laser head is also externally connected to a metal powder conveying device. The laser head performs wire filling laser cladding through the wire feeding nozzle, and the laser head performs powder feeding laser cladding through the metal powder conveying device.

[0007] As a further solution of the present invention: the laser head is fixedly connected to a coaxial clamp, and the laser head is coaxially fixed to the ultrasonic vibration device and the wire feeding nozzle through the coaxial clamp.

[0008] As a further solution of the present invention: the ultrasonic vibration device, the wire feeding nozzle and the laser head are in the same plane.

[0009] As a further solution of the present invention, the angle adjustment of the ultrasonic vibration device and the height and angle adjustment of the wire feeding nozzle are all carried out synchronously with the defocusing amount of the laser head.

[0010] As a further solution of the present invention: the laser head is further externally connected to a protective gas delivery device and a laser water cooling device.

[0011] As a further solution of the present invention: a wire feeder is further provided on one side of the laser head, and the wire feeder supplies the metal wire to the wire feeding nozzle.

[0012] As a further solution of the present invention: the ultrasonic vibration device is located above the molten pool.

[0013] As a further solution of the present invention: the ultrasonic vibration device includes a transducer, a cooler, a variable amplitude rod, a protective sleeve and a waveform tool, the variable amplitude rod is connected to the front end of the transducer, the outer cover of the variable amplitude rod is provided with a protective sleeve, the outer side of the transducer is connected to the cooler, the protective sleeve is fixedly connected to the outer wall of the cooler, the waveform tool is arranged in the protective sleeve, and the waveform tool is fixedly connected to the front end of the variable amplitude rod, and the outer end face of the waveform tool is provided with an inward concave spherical surface.

[0014] As a further solution of the present invention: the ultrasonic vibration device is connected to an ultrasonic water cooling device through a water pipe, and a water inlet and a water outlet are respectively provided on both sides of the cooler. The cooling water output end of the ultrasonic water cooling device is connected to the water inlet through the water pipe, and the cooling water input end of the ultrasonic water cooling device is connected to the water outlet through the water pipe.

[0015] A method for using an ultrasonic in-situ assisted laser cladding device, the method comprising the following steps: 1. Place the workpiece on the workbench, select the continuous laser power, continuous laser scanning speed, gas delivery of the protective gas delivery device, and powder delivery of the metal powder delivery device, and draw the processing curve in the electronic computer according to the sample processing requirements; 2. When performing wire-filled laser cladding, it is necessary to turn off the metal powder conveying device. Instead, turn on the wire feeder, set the wire feeding speed, and adjust the height and angle of the wire feeding nozzle. 3. Adjust the angle of the ultrasonic vibration device and the distance between it and the molten pool, and set the energy and frequency of the ultrasonic wave as needed; 4. Start processing. The laser head emits laser to melt the metal powder or wire within the irradiation range, and gathers it into a molten pool on the workpiece. The ultrasonic focus acts on the surface of the molten pool.

[0016] The beneficial effects of the present invention are: 1) This invention uses a coaxial fixture to rigidly connect the laser head, ultrasonic vibration device, and wire feed nozzle to achieve seamless switching between powder feeding and wire filling cladding modes. This solves the path interference problem caused by the tungsten wire independently extending into the molten pool in the prior art, and is particularly suitable for large-area cladding of complex curved workpieces. 2) This invention positions the ultrasonic vibrator directly above the molten pool, focusing the ultrasonic waves onto the molten pool surface via the spherical surface of the waveform tool. This reduces energy loss compared to existing patents that indirectly conduct the ultrasound through a tungsten wire. Furthermore, the height and angle of the wire feed nozzle are synchronously controlled with the laser defocus, ensuring that the metal wire is precisely melted at the laser focus. This overcomes the molten pool disturbance caused by the fixed position of the tungsten wire in existing technologies. 3) The present invention uses an electronic computer to integrate and control the ultrasonic frequency, wire feeding speed, and laser parameters, allowing the ultrasonic focus to track the position of the molten pool in real time, solving the problem of uneven ultrasonic action caused by the size of the substrate during the processing of large workpieces. The combination of the ultrasonic water cooling device and the cooler ensures the continuous and stable operation of the ultrasonic vibration device in a high-temperature environment, avoiding the risk of high-temperature breakage of the tungsten wire in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of conventional ultrasonic-assisted laser cladding; Figure 2 This is a schematic diagram of the structure in which the ultrasonic vibration device and the laser head are coaxially fixed; Figure 3 This is a schematic structural diagram of the ultrasonic in-situ assisted laser cladding device of the present invention; Figure 4 is a structural diagram of the ultrasonic vibration device of the present invention; In the figure: 1. Laser head; 2. Coaxial fixture; 3. Ultrasonic vibration device; 31. Transducer; 32. Cooler; 321. Water inlet; 322. Water outlet; 33. Amplitude transformer; 34. Protective sleeve; 35. Wave tool; 4. Wire feed nozzle; 41. Metal wire; 5. Continuous laser; 6. Workbench; 61. Workpiece; 7. Electronic computer; 8. Ultrasonic frequency generator; 9. Ultrasonic water cooling device; 10. Wire feeder; 11. Shielding gas delivery device; 12. Laser water cooling device; 13. Metal powder delivery device; 14. Moving frame. DETAILED DESCRIPTION

[0018] The following will clearly and completely describe the technical solutions in the embodiments of the present invention 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 making creative efforts are within the scope of protection of the present invention.

[0019] Example 1, as Figures 2 to 4As shown, an ultrasonic in-situ assisted laser cladding device includes a laser head 1 and an electronic computer 7. The electronic computer 7 controls a laser cladding manufacturing module and an ultrasonic module. A workbench 6 is provided below the laser head 1, and a workpiece 61 is placed on the workbench 6. The workpiece 61 is placed on the workbench 6 for cladding. The laser cladding manufacturing module includes a continuous laser 5 and a movable frame 14. The continuous laser 5 is connected to the laser head 1 through a continuous laser optical fiber. The laser head 1 is fixed on the movable frame 14. The ultrasonic module includes an ultrasonic vibration device 3 and an ultrasonic frequency generator 8. The ultrasonic frequency generator 8 is respectively connected to the electronic computer 7 and the ultrasonic vibration device 3. The ultrasonic vibration device 3 is connected to one side of the laser head 1. The other side of the laser head 1 is connected to a wire feeding nozzle 4. The wire feeding nozzle 4 sprays out a metal wire 41. The laser head 1 is also externally connected to a metal powder conveying device 13. The laser head 1 performs wire filling laser cladding through the wire feeding nozzle 4, and the laser head 1 performs powder feeding laser cladding through the metal powder conveying device 13.

[0020] Example 2. In addition to all the technical features of Example 1, this embodiment also includes: the laser head 1 is fixedly connected to the coaxial clamp 2, and the laser head 1 is coaxially fixed to the ultrasonic vibration device 3 and the wire feeding nozzle 4 through the coaxial clamp 2, ensuring that the laser head 1, the ultrasonic vibration device 3 and the wire feeding nozzle 4 can be relatively stationary during the movement. That is, whether it is powder feeding laser cladding, wire filling laser cladding or other types of laser cladding, it can solve the technical problem that ultrasonic waves are difficult to work when performing laser cladding on workpieces of unconventional size, shape and quality. It can also further solve the problem that the height and angle of the wire in wire filling laser cladding are difficult to control, and at the same time solve the problem that the wire feeding process hinders the laser cladding path.

[0021] The ultrasonic vibration device 3 , the wire feeding nozzle 4 and the laser head 1 are located in the same plane to ensure that the metal wire 41 ejected from the wire feeding nozzle 4 can be completely melted.

[0022] The angle adjustment of the ultrasonic vibration device 3 and the height and angle adjustment of the wire feeding nozzle 4 are synchronized with the defocus amount of the laser head 1 to ensure that the metal wire 41 always contacts the focus of the laser and the focus of the ultrasonic wave is on the molten pool.

[0023] The laser head 1 is also externally connected to a protective gas delivery device 11 and a laser water cooling device 12 , which can realize delivery protection and water cooling of the laser head 1 during operation.

[0024] A wire feeder 10 is also provided on one side of the laser head 1. The wire feeder 10 supplies the metal wire 41 to the wire feeding nozzle 4. The wire feeding nozzle 4 adjusts the height and direction of the metal wire 41. The wire feeder 10 controls the speed of the metal wire 41 to achieve cladding control during wire filling laser cladding.

[0025] The ultrasonic vibration device 3 is located above the molten pool, so that the ultrasonic vibration device 3 can emit ultrasonic waves to the molten pool from top to bottom, solving the problem that a large amount of energy is wasted in the process of ultrasonic waves passing through the workpiece 61, thereby weakening the effect of ultrasonic waves on the molten pool.

[0026] The ultrasonic vibration device 3 includes a transducer 31, a cooler 32, a horn 33, a protective sleeve 34 and a waveform tool 35. The horn 33 is connected to the front end of the transducer 31. The outer cover of the horn 33 is provided with a protective sleeve 34. The outer side of the transducer 31 is connected to the cooler 32. The protective sleeve 34 is fixedly connected to the outer wall of the cooler 32. The waveform tool 35 is arranged in the protective sleeve 34, and the waveform tool 35 is fixedly connected to the front end of the horn 33. The outer end face of the waveform tool 35 is provided with a concave spherical surface. The energy and frequency used for the ultrasonic wave are configured in the electronic computer 7. The corresponding current is generated by the ultrasonic frequency generator 8. The current enters the ultrasonic vibration device 3 through the wire. The transducer 31 converts the input current into a magnetic field, causing the horn 33 to undergo magnetostriction, driving the waveform tool 35 to vibrate at the frequency of the current to generate ultrasonic waves, and the ultrasonic waves are gathered at the center of the spherical surface on the waveform tool 35.

[0027] The ultrasonic vibration device 3 is connected to the ultrasonic water cooling device 9 through a water pipe. A water inlet 321 and a water outlet 322 are respectively provided on both sides of the cooler 32. The cooling water output end of the ultrasonic water cooling device 9 is connected to the water inlet 321 through a water pipe, and the cooling water input end of the ultrasonic water cooling device 9 is connected to the water outlet 322 through a water pipe. The cooling water circulates between the ultrasonic water cooling device 9 and the cooler 32 through the water pipe provided, which can cool the transducer 31 and the end of the amplitude rod 33.

[0028] Example 3, a method for using an ultrasonic in-situ assisted laser cladding device, including a cladding device, the method comprising the following steps: 1. Place the workpiece 61 on the workbench 6, select the continuous laser power, continuous laser scanning speed, the air delivery rate of the protective gas delivery device, and the powder delivery rate of the metal powder delivery device, and draw a processing curve in the electronic computer 7 according to the sample processing requirements; 2. When performing wire-filling laser cladding, the metal powder conveying device 13 needs to be turned off. Instead, the wire feeder 10 is turned on, the wire feeding speed is set, and the height and angle of the wire feeding nozzle 4 are adjusted; 3. Adjust the angle of the ultrasonic vibration device 3 and its distance from the molten pool, and set the energy and frequency of the ultrasonic wave as needed; 4. Processing begins. The laser head 1 emits a laser to melt the metal powder or wire within the irradiation range, which converges into a molten pool on the workpiece 61. The ultrasonic focus acts on the surface of the molten pool.

[0029] Working principle: The ultrasonic frequency generator 8 generates current to drive the transducer 31, and the magnetostrictive effect causes the amplitude transformer 33 to drive the waveform tool 35 to vibrate at high frequency, and its spherical end focuses the ultrasonic wave on the surface of the molten pool; the protective gas channel 11 isolates oxidation, and the metal powder / metal wire 41 is injected into the laser focus through the coaxial powder feeding or wire filling nozzle 4; the movable frame 14 drives the laser head 1, the ultrasonic vibration device 3 and the wire feeding nozzle 4 to move as a whole, and the relative positions of the three are maintained constant by the coaxial clamp 2; the computer 7 dynamically adjusts the angle of the ultrasonic device and the height of the wire feeding nozzle to always match the laser defocus amount, ensuring that the metal wire 41 melts at the focus and the ultrasonic wave focuses on the molten pool; the metal powder conveying device 13 is activated during powder feeding and cladding, and the wire feeding machine 10 is switched and the powder feeding is turned off during wire filling and cladding; the cooling water circulates through the water inlet 321 / water outlet 322 to cool the transducer 31 and the amplitude transformer 33, ensuring that the ultrasonic device continues to work in the high temperature environment of the molten pool.

[0030] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0031] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. An ultrasonic in-situ assisted laser cladding device, comprising a laser head (1) and an electronic computer (7), characterized in that: The electronic computer (7) controls a laser cladding manufacturing module and an ultrasonic module. A workbench (6) is provided below the laser head (1). A workpiece (61) is placed on the workbench (6). The workpiece (61) is placed on the workbench (6) for cladding. The laser cladding manufacturing module includes a continuous laser (5) and a movable frame (14), wherein the continuous laser (5) is connected to a laser head (1) via a continuous laser optical fiber, and the laser head (1) is fixed on the movable frame (14); the ultrasonic module includes an ultrasonic vibration device (3) and an ultrasonic frequency generator (8), wherein the ultrasonic frequency generator (8) is connected to an electronic computer (7) and the ultrasonic vibration device (3), respectively; the ultrasonic vibration device (3) is connected to one side of the laser head (1), and the other side of the laser head (1) is connected to a wire feeding nozzle (4), wherein the wire feeding nozzle (4) ejects a metal wire (41); the laser head (1) is further externally connected to a metal powder conveying device (13), and the laser head (1) performs wire-filling laser cladding via the wire feeding nozzle (4), and the laser head (1) performs powder feeding laser cladding via the metal powder conveying device (13).

2. The ultrasonic in-situ assisted laser cladding device according to claim 1, characterized in that: The laser head (1) is fixedly connected to a coaxial clamp (2), and the laser head (1) is coaxially fixed to the ultrasonic vibration device (3) and the wire feeding nozzle (4) through the coaxial clamp (2).

3. The ultrasonic in-situ assisted laser cladding device according to claim 1, characterized in that: The ultrasonic vibration device (3), the wire feeding nozzle (4) and the laser head (1) are located in the same plane.

4. The ultrasonic in-situ assisted laser cladding device according to claim 1, characterized in that: The angle adjustment changes of the ultrasonic vibration device (3) and the height and angle adjustment changes of the wire feeding nozzle (4) are all performed synchronously with the defocusing amount of the laser head (1).

5. The ultrasonic in-situ assisted laser cladding device according to claim 1, characterized in that: The laser head (1) is also externally connected to a protective gas delivery device (11) and a laser water cooling device (12).

6. The ultrasonic in-situ assisted laser cladding device according to claim 1, characterized in that: A wire feeder (10) is also provided on one side of the laser head (1), and the wire feeder (10) supplies the metal wire (41) to the wire feeding nozzle (4).

7. The ultrasonic in-situ assisted laser cladding device according to claim 1, characterized in that: The ultrasonic vibration device (3) is located above the molten pool.

8. The ultrasonic in-situ assisted laser cladding device according to claim 1, characterized in that: The ultrasonic vibration device (3) comprises a transducer (31), a cooler (32), a horn (33), a protective sleeve (34) and a waveform tool (35), wherein the horn (33) is connected to the front end of the transducer (31), the outer cover of the horn (33) is provided with a protective sleeve (34), the outer side of the transducer (31) is connected to the cooler (32), the protective sleeve (34) is fixedly connected to the outer wall of the cooler (32), the waveform tool (35) is arranged in the protective sleeve (34), and the waveform tool (35) is fixedly connected to the front end of the horn (33), and the outer end surface of the waveform tool (35) is provided with an inner concave spherical surface.

9. The ultrasonic in-situ assisted laser cladding device according to claim 8, characterized in that: The ultrasonic vibration device (3) is connected to an ultrasonic water cooling device (9) via a water pipe. A water inlet (321) and a water outlet (322) are respectively provided on both sides of the cooler (32). The cooling water output end of the ultrasonic water cooling device (9) is connected to the water inlet (321) via a water pipe, and the cooling water input end of the ultrasonic water cooling device (9) is connected to the water outlet 322 via a water pipe.

10. A method for using an ultrasonic in-situ assisted laser cladding device, comprising the ultrasonic in-situ assisted laser cladding device according to any one of claims 1 to 9, characterized in that: The method of use comprises the following steps:

1. Place the workpiece (61) on the workbench (6), select the continuous laser power, the continuous laser scanning speed, the air delivery of the protective gas delivery device, and the powder delivery of the metal powder delivery device, and draw a processing curve in the electronic computer (7) according to the sample processing requirements; 2. When performing wire-filling laser cladding, the metal powder conveying device (13) needs to be turned off. Instead, the wire feeder (10) is turned on, the wire feed speed is set, and the height and angle of the wire feed nozzle (4) are adjusted; 3. Adjust the angle of the ultrasonic vibration device (3) and its distance from the molten pool, and set the energy and frequency of the ultrasonic wave as needed; 4. Processing begins. The laser head (1) emits laser light to melt the metal powder or metal wire within the irradiation range, which converges into a molten pool on the workpiece (61). The ultrasonic focus acts on the surface of the molten pool.

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