Coaxial ultrasonic enhanced laser processing device and method

Abstract

The invention relates to the technical field of laser processing, in particular to a coaxial ultrasonic enhanced laser processing device which comprises an ultrasonic transducer, an amplitude-change pole, a shell and a laser processing assembly, the laser processing assembly is composed of a plurality of modules, and the modules are connected through screws or threads. The shell is connected with the flange at the zero amplitude of the transducer through a screw, and the laser processing assembly is connected with the shell through a thread. The ultrasonic amplitude-change pole does not make contact with the laser machining assembly, and the laser machining assembly is prevented from vibrating together. The ultrasonic transducer is connected with the amplitude-change pole, and through holes which are communicated with each other are formed in the centers of the ultrasonic transducer and the amplitude-change pole, so that the introduction of coaxial gas is ensured. The interior of the nozzle is in a conical design, so that the laser action area is enhanced through ultrasonic convergence. According to the coaxial ultrasonic enhanced laser processing device, ultrasound is introduced in the laser processing process through a non-contact method, and the coaxial ultrasonic enhanced laser processing device is suitable for laser welding, cutting, cladding and the like.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of laser processing, and particularly relates to a coaxial ultrasonic enhanced laser processing device. BACKGROUND

[0002] Laser processing technology is an advanced processing technology, which has the advantages of high efficiency, high flexibility and easy operation. Laser processing is a kind of non-contact processing, which has the advantages of high processing speed and small surface deformation, and can process various materials, and can process various metals and non-metals, especially can process high-hardness, high-brittle and high-melting-point materials, and is mainly used for punching, cutting, welding and surface treatment. At present, laser processing technology is developing towards intelligence, refinement and multi-function, and has a broad application prospect in the future. However, the plasma in the laser processing process will absorb and shield the laser, which reduces the utilization rate of the laser, and the processing waste and splashing will also affect the appearance and size precision after processing. Single laser processing has its inevitable shortcomings, but laser processing has its unique advantages, so researchers are constantly looking for other processing methods combined with laser processing to improve the shortcomings of laser processing and play the advantages of laser processing.

[0003] Ultrasonic energy is easy to concentrate, has high energy density and strong penetration. The acceleration of ultrasonic vibration is very high, and in liquid medium, cavitation phenomenon can be generated, which has strong impact force on the medium. Due to these special properties, ultrasonic technology is widely used in various fields such as industry, petrochemical industry and medicine. The processing form of combining ultrasonic processing with other processing technologies is called ultrasonic composite processing or ultrasonic wave assisted processing. This method deepens the process of the original processing, significantly improves the processing speed, and improves the processing quality, achieving the goal of low consumption and high efficiency. Due to the great advantages of composite processing, it has received widespread attention in recent years, and has been used to different degrees in various fields.

[0004] In order to introduce ultrasonic into the coaxial laser processing process, Chinese Patent Application No. 202210369096.3 discloses a coaxial ultrasonic-assisted ultrafast laser drilling unit and method, which connects the laser head with the ultrasonic output end to make the laser head produce axial ultrasonic vibration to improve the efficiency and precision of laser drilling, but does not directly act ultrasonic on the laser processing area, but acts on the laser processing assembly, and the lens is easy to be broken in high-frequency vibration. Chinese Patent Application No. 202310988486.3 discloses a coaxial focused ultrasonic composite laser processing device and method, which conducts ultrasonic through the liquid film on the surface of the workpiece, so that various products generated in the laser processing process are quickly cooled under the action of the liquid film and are broken and quickly discharged under the action of ultrasonic vibration, but this method is not suitable for laser welding, which will add hydrogen and oxygen in the weld, and deteriorate the performance of the weld. Chinese Patent Application No. 201910950188.9 discloses an ultrasonic vibration device for coaxial ultrasonic-assisted laser peening, and Chinese Patent Application No. 201610027124.8 discloses a plate heat exchanger ultrasonic coaxial auxiliary laser welding method. The ultrasonic vibration tool head directly contacts the heat exchanger plate during laser processing. However, the plasma generated in the laser processing process of the two methods will burn the ultrasonic vibration tool head on the one hand, and will produce scratches on the surface of the workpiece on the other hand, which is easy to produce stress concentration points, and is not suitable for components sensitive to stress concentration. SUMMARY

[0005] Therefore, the purpose of the present application is to provide a processing device with stable performance, which can realize various laser processing methods, and solve the technical problems of low laser utilization rate and poor processing surface quality in the prior art by introducing coaxial non-contact ultrasonic. The laser processing depth is improved, the processing depth is improved, and the processing quality is improved.

[0006] According to a first aspect of the present application, a coaxial ultrasonic enhanced laser processing device is provided, comprising an ultrasonic transducer, an amplitude changer, a shell, and a laser processing assembly. The laser processing assembly is composed of multiple modules, and each module is connected by screws or threads. The shell is connected to the flange where the amplitude of the transducer is zero by screws, and the laser processing assembly is connected to the shell by threads. The ultrasonic amplitude changer does not contact the laser processing assembly, preventing the laser processing assembly from vibrating together. The ultrasonic transducer is connected to the amplitude changer, and a through hole is provided in the center of the two to ensure the passage of coaxial air. The nozzle is designed in a conical shape to concentrate and enhance the laser action area.

[0007] Preferably, the ultrasonic transducer is composed of an upper end cover and four pieces of pressed ceramic, which are connected to the amplitude changer by a hollow stud in the center and are pressed tightly.

[0008] Preferably, the outer casing is connected to the flange at the zero amplitude point of the transducer by screws, and the laser processing assembly is connected to the outer casing by threads. The amplitude transformer and the laser processing assembly do not contact each other to prevent the laser processing assembly from vibrating together and damaging the lens. The ultrasonic transducer is connected to the amplitude transformer, and a through hole is provided at the center of both to ensure the passage of coaxial gas.

[0009] Preferably, the laser processing component consists of a QBH connector, a collimation module, a refraction focusing module, and a nozzle.

[0010] Preferably, the QBH connector is fixed to the collimation module by a set screw, the collimation module is connected to the refraction focusing module by screws, and the refraction focusing module is connected to the nozzle by threads. The collimation lens is fixed to the collimation module by a retaining ring, the refraction lens end cap is pressed onto the refraction lens and connected to the refraction focusing module by screws, and the focusing lens is fixed to the refraction focusing module by a retaining ring.

[0011] Preferably, the nozzle bypass is provided with an optical path channel, with a conical hole at the center, which can focus the ultrasound to enhance the laser's action area. Simultaneously, a wire and powder feeding channel is reserved on the other side to accommodate different needs such as laser welding, laser cutting, laser cladding, and laser drilling.

[0012] Preferably, according to a second aspect of the present invention, the coaxial ultrasonic-enhanced laser processing apparatus is characterized by comprising the following steps: Step 1: Secure the QBH of the laser fiber to the QBH connector on the side. Step 2: Adjust the distance between the nozzle and the top of the workpiece according to different processing requirements, turn on the ultrasonic power supply, and introduce protective gas or high-pressure gas; Step 3: After ventilating for 10-15 seconds, adjust the laser welding parameters and begin the processing. Step 4: After welding is completed, turn off the laser, ultrasonic power supply and shielding gas in sequence.

[0013] Preferably, the coaxial gas can be an inert protective gas or high-pressure air, and the ultrasonic frequency is 10KHz-30KHz.

[0014] This invention provides a coaxial ultrasonic-enhanced laser processing device that couples ultrasonic vibration with laser processing to act on the workpiece, achieving superior processing speed and quality for difficult-to-machine materials. Introducing ultrasound suppresses the upward movement of plasma, and the negative pressure effect causes plasma diffusion. Simultaneously, it reduces the adsorption of waste and residue from the laser processing, improving surface finish. Finally, the ultrasound is transmitted to the workpiece via the plasma, which can refine the grains. This design combines an ultrasonic vibration system with a laser processing system, enabling various processing modes (such as welding, cutting, drilling, and cladding). It improves processing speed and surface quality without affecting dimensional accuracy. The vibration system's amplitude can vary within a few micrometers, thus comprehensively improving the quality and efficiency of laser processing and welding. Attached Figure Description

[0015] The above and other objects, features and advantages of the invention will become clearer from the following description of examples of the invention with reference to the accompanying drawings.

[0016] Figure 1 This is a schematic diagram of a coaxial ultrasonic-enhanced laser processing device according to the present invention.

[0017] Figure 2 This is a cross-sectional view of a coaxial ultrasonic-enhanced laser processing device according to the present invention.

[0018] Figure 3 This is a front view of a coaxial ultrasonic-enhanced laser processing device according to the present invention. Specific implementation methods

[0019] Various embodiments of the invention will now be described in more detail with reference to the accompanying drawings, in which the same elements are indicated by the same or similar reference numerals.

[0020] This invention provides a coaxial ultrasonic-enhanced laser processing device, comprising an ultrasonic transducer, a protective shell, an amplitude transformer, and laser processing components. The structure and usage of the underwater laser-ultrasonic composite welding torch of this invention are described in detail below with reference to specific embodiments.

[0021] See Figure 1 and Figure 2The present invention provides a coaxial ultrasonic-enhanced laser processing device comprising an ultrasonic transducer 1, a protective shell 2, an amplitude transformer 9, and a laser processing assembly 3. The ultrasonic transducer 1 consists of an upper end cover 6 and four pressure ceramic plates 7. Hollow bolts 5 pass through the upper end cover 6 and the pressure ceramic plates 7 and are fastened together with the amplitude transformer 9, pressing the pressure ceramic plates 7 tightly. A flange 8 is located at the zero-amplitude position of the transducer 1 and is connected to the protective shell 2 by four screws. The laser processing module 3 is threadedly connected to the protective shell 2. The laser processing module 3 consists of a QBH connector 10, a collimation module 11, a refraction focusing module 13, and a nozzle 4. The QBH connector 10 is fixed to the collimation module 11 by set screws. The collimation module 11 is connected to the refraction focusing module 13 by screws, and the refraction focusing module 13 is threadedly connected to the nozzle 4. The collimating lens 12 is fixed to the collimating module by a retaining ring 17, the focusing lens 16 is fixed to the refractive focusing module by a retaining ring 17, the refractive lens end cap 15 is pressed on the refractive lens 14 and connected to the refractive focusing module 13 by screws.

[0022] See Figure 3 This is a front view of the coaxial ultrasonic-enhanced laser processing device of the present invention. The amplitude transformer 9 is not in contact with the laser processing component 3 to prevent the laser processing component from vibrating together. The ultrasonic transducer 1 is connected to the amplitude transformer 9, and a through hole 18 is provided at the center of both to ensure the passage of coaxial gas. A light path channel is provided in the bypass of the nozzle 4 to ensure the passage of the laser light path 19. The center is a conical hole 21, which can focus the ultrasound to enhance the laser action area. At the same time, a wire feeding and powder feeding channel 20 is reserved on the other side to adapt to different needs such as laser welding, laser cutting, laser cladding, and laser drilling.

[0023] The method of using the coaxial ultrasonic-enhanced laser processing device provided by this invention is as follows: Step 1: Secure the QBH of the laser fiber to the QBH connector on the side. Step 2: Adjust the distance between the nozzle and the top of the workpiece according to different processing requirements, turn on the ultrasonic power supply, and introduce protective gas or high-pressure gas; Step 3: After ventilating for 10-15 seconds, adjust the laser welding parameters and begin the processing. Step 4: After welding is completed, turn off the laser, ultrasonic power supply and shielding gas in sequence.

[0024] Preferably, the coaxial gas can be an inert protective gas or high-pressure air, and the ultrasonic frequency is 10KHz-30KHz.

[0025] This invention provides a coaxial ultrasonic-enhanced laser processing device that couples ultrasonic vibration with laser processing to act on the workpiece, achieving superior processing speed and quality for difficult-to-machine materials. Introducing ultrasound suppresses the upward movement of plasma, and the negative pressure effect causes plasma diffusion. Simultaneously, it reduces the adsorption of waste and residue from the laser processing, improving surface finish. Finally, the ultrasound is transmitted to the workpiece via the plasma, which can refine the grains. This design combines an ultrasonic vibration system with a laser processing system, enabling various processing modes (such as welding, cutting, drilling, and cladding). It improves processing speed and surface quality without affecting dimensional accuracy. The vibration system's amplitude can vary within a few micrometers, thus comprehensively improving the quality and efficiency of laser processing and welding.

[0026] Finally, it should be noted that, for those skilled in the art, other variations or modifications can be made based on the above description, and any obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A coaxial ultrasonic-enhanced laser processing device, characterized in that, The system includes an ultrasonic transducer, an amplitude transformer, a housing, and a laser processing assembly. The laser processing assembly consists of multiple modules connected by screws or threads. The housing is connected to the flange at the zero-amplitude point of the transducer by screws, and the laser processing assembly is connected to the housing by threads. The ultrasonic amplitude transformer and the laser processing assembly do not contact each other to prevent the laser processing assembly from vibrating together. The ultrasonic transducer is connected to the amplitude transformer, and a through-hole is provided at the center of both to ensure the passage of coaxial gas. The nozzle has a conical internal design to focus the ultrasound and enhance the laser's effective area.

2. The coaxial ultrasonic-enhanced laser processing device according to claim 1, characterized in that, The ultrasonic transducer consists of an upper end cover and four ceramic plates, which are connected to the amplitude transformer by a central hollow stud, thus pressing the ceramic plates together.

3. The coaxial ultrasonic-enhanced laser processing device according to claim 1, characterized in that, The outer casing is connected to the flange at the zero amplitude point of the transducer by screws, and the laser processing assembly is connected to the outer casing by threads. The amplitude transformer does not contact the laser processing assembly to prevent the laser processing assembly from vibrating together and damaging the lens. The ultrasonic transducer is connected to the amplitude transformer, and a through hole is provided at the center of both to ensure the passage of coaxial gas.

4. The coaxial ultrasonic-enhanced laser processing device according to claim 1, characterized in that, The laser processing assembly consists of a QBH connector, a collimation module, a refraction focusing module, and a nozzle.

5. The laser processing assembly according to claim 4, characterized in that, The QBH connector is fixed to the collimation module by a set screw. The collimation module is connected to the refraction focusing module by screws, and the refraction focusing module is connected to the nozzle by threads. The collimation lens is fixed to the collimation module by a retaining ring. The refraction lens end cap is pressed onto the refraction lens and connected to the refraction focusing module by screws. The focusing lens is fixed to the refraction focusing module by a retaining ring.

6. The nozzle according to claim 4, characterized in that, The bypass is equipped with an optical path channel, with a conical hole at the center, which can focus the ultrasound to enhance the laser's effective area. Meanwhile, a wire and powder feeding channel is reserved on the other side to accommodate different needs such as laser welding, laser cutting, laser cladding, and laser drilling.

7. The coaxial ultrasonic-enhanced laser processing device according to claim 1, characterized in that, Includes the following steps: Step 1: Secure the QBH of the laser fiber to the QBH connector on the side. Step 2: Adjust the distance between the nozzle and the top of the workpiece according to different processing requirements, turn on the ultrasonic power supply, and introduce protective gas or high-pressure gas; Step 3: After ventilating for 10-15 seconds, adjust the laser welding parameters and begin the processing. Step 4: After welding is completed, turn off the laser, ultrasonic power supply and shielding gas in sequence.

8. The underwater laser-ultrasonic composite welding torch suitable for deep water as described in claim 1, characterized in that, The coaxial gas can be an inert protective gas or high-pressure air, with an ultrasonic frequency of 10KHz-30KHz.

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