Water-jet-guided laser processing device and method under multi-layer water-gas composite mode

Abstract

Disclosed in the present invention are a water-jet-guided laser processing device and method under a multi-layer water-gas composite mode. An auxiliary atmosphere input gas path (9) is arranged in an interlayer between a laser-water coupling device (2) and an annular water jet device (3); the auxiliary atmosphere input gas path (9) enables auxiliary atmosphere to be sprayed out through an annular gas nozzle (6) to form an auxiliary gas flow layer (8); a nozzle (4) is arranged at the lower end of the laser-water coupling device (2); an annular liquid nozzle (5) is arranged at the bottom of the annular water jet device (3); the laser-water coupling device (2) is used for coupling a laser beam (1) and internal liquid and then spraying out a single water jet (10) from the nozzle (4); the annular water jet device (3) is used for spraying out the internal liquid from the annular liquid nozzle (5) and then forming an annular water curtain (7) surrounding the single water jet (10); and the annular water curtain (7) wraps the auxiliary gas flow layer (8). The present invention is used for effectively increasing the stable jet length.

Description

Water-guided laser processing device and processing method under multiple water-air composite modes Technical Field

[0001] The present invention belongs to the technical field of laser processing, and in particular relates to a water-guided laser processing device and a processing method thereof in a multiple water-air composite mode. Background Art

[0002] In high-end manufacturing industries such as aerospace equipment, medical devices, and semiconductor micromachining, the production of many critical precision components places extremely high demands on machining accuracy, efficiency, thermal damage, and fracture quality. Conventional machining methods struggle to effectively meet these requirements. Water-guided laser technology is an environmentally friendly, efficient, and precision machining technology. Its principle is to couple a high-energy laser beam into a fine water jet, which then directs the laser onto the workpiece surface for precision thermal machining such as cutting, drilling, and grooving. The water jet also removes excess heat and debris. Therefore, water-guided laser technology enables precise control of high-density energy in a "cold and hot source" mode, resulting in ultra-precise, efficient, and high-quality cuts. This technology is ideally suited for the fine machining of materials such as high-temperature alloys, wafers, and carbon fibers, as well as for the processing of biomedical device components. However, two key factors determine the precision machining capabilities of water-guided lasers: water jet diameter and stable water jet length. The water jet diameter significantly influences machining accuracy. The smaller the nozzle diameter, the smaller the water jet diameter, and the higher the machining accuracy. Furthermore, the processing depth and distance of water-guided lasers are both dependent on the stable length of the light-guiding water jet—the length of the jet segment that provides optimal light guidance. This segment features a smooth, clean surface and a tightly packed, cylindrical flow. Therefore, the industry is highly focused on these two technical indicators. However, achieving consistent results in both is difficult. This is because, upon exiting the nozzle, the high-pressure water jet experiences intense friction with the surrounding air, disrupting the stable laminar flow within. Consequently, after a certain distance, the water jet destabilizes, breaking up and forming droplets, which disrupt the light-water coupling channel. Research has shown that smaller water jet diameters are more susceptible to this effect, resulting in a shorter stable water jet length. While some researchers have attempted to isolate the water jet nozzle from the air and extend the stable flow length, the auxiliary atmosphere still experiences intense friction with the surrounding air. Therefore, the distance over which the auxiliary atmosphere can maintain its tightness is extremely limited, and its protective effect disappears after dissipating a certain distance. Therefore, the current water-guided laser technology is still a contradiction in terms of processing accuracy and processing thickness, and it is difficult to ensure both at the same time.

[0003] During water-guided laser processing, the fine light-guiding water jet is extremely susceptible to severe friction from the surrounding air during the spraying process, gradually deviating from the stable state, resulting in the destruction of the stable light-guiding channel. Therefore, how to effectively extend the stable jet length is a key issue.

[0004] Summary of the Invention

[0005] The object of the present invention is to provide a water-guided laser processing device and a processing method thereof in a multiple water-air composite mode, which can effectively extend the stable water jet length and enhance processing stability while keeping the water jet diameter unchanged.

[0006] The present invention is achieved through the following technical solutions:

[0007] A water-guided laser processing device in a multiple water-air composite mode, the water-guided laser processing device includes a light-water coupling device 2, an annular water jet device 3, a nozzle 4 and an annular liquid nozzle 5, and an auxiliary atmosphere input gas path 9.

[0008] An auxiliary atmosphere input gas path 9 is provided in the interlayer between the light-water coupling device 2 and the annular water jet device 3. The auxiliary atmosphere input gas path 9 ejects the auxiliary atmosphere through the annular gas nozzle 6 to form an auxiliary airflow layer 8. A nozzle 4 is provided at the lower end of the light-water coupling device 2, and an annular liquid nozzle 5 is provided at the bottom of the annular water jet device 3. The light-water coupling device 2 is used to couple the laser beam 1 with the internal liquid and then eject a single water jet 10 from the nozzle 4. The annular water jet device 3 is used to eject the internal liquid from the annular liquid nozzle 5 to form an annular water curtain 7 surrounding the light-guiding water jet 10, and the annular water curtain 7 covers the auxiliary airflow layer 8.

[0009] Furthermore, the single-channel water jet 10, the auxiliary airflow layer 8 and the annular water curtain 7 are a coaxial composite structure from the inside to the outside, that is, an inside-outside coaxial composite structure under multiple water-air-water modes.

[0010] Furthermore, the annular water jet device 3 is connected to the lower end of the optical-water coupling device 2 .

[0011] Furthermore, a laser emitting device is provided above the optical-water coupling device 2 for emitting the laser beam 1 into the optical-water coupling device 2 .

[0012] Furthermore, the laser beam 1 is a single energy beam or a composite energy beam.

[0013] Furthermore, the optical-water coupling device 2 and the annular water jet device 3 are both provided with high-pressure water inlets.

[0014] A water-guided laser processing method in a multiple water-air composite mode, the water-guided laser processing method comprising the following steps:

[0015] Step 1: ejecting water in the water-guided laser processing device at high speed under pressure to form a single water jet;

[0016] Step 2: Coaxially compound an auxiliary atmosphere to enclose the single water jet formed in step 1, and coaxially compound another annular water curtain outside the auxiliary atmosphere to form an internal and external coaxial composite structure under multiple water-air-water modes;

[0017] Step 3: Couple the high-energy laser beam into the single-channel water jet formed in step 1 to form a light-guiding water jet, and spray it onto the surface of the workpiece to be processed together with the auxiliary atmosphere and the annular water curtain.

[0018] Furthermore, the diameter of the single-channel water jet in step 1 is 10-600 μm, and the water pressure ranges from 0-100 MPa.

[0019] Furthermore, the auxiliary atmosphere gas pressure in step 2 is 0.1-10 MPa.

[0020] Furthermore, the water in the light-water coupling device and the annular water jet device includes pure water or distilled water or other liquids that meet the light guiding requirements.

[0021] The beneficial effects of the present invention are:

[0022] The present invention effectively extends the stable water jet length and enhances processing stability while keeping the water jet diameter unchanged.

[0023] The present invention is used to improve the stable jet length, processing stability and anti-interference ability in water-guided laser cutting, drilling, grooving and other processing.

[0024] The present invention significantly outperforms conventional auxiliary atmosphere protection methods in extending the length of a stable water jet. Conventional auxiliary atmosphere protection methods apply a coaxial auxiliary atmosphere to the exterior of the light-guiding water jet. While this method can, to a certain extent, isolate the air and extend the stable length of the light-guiding water jet, the auxiliary atmosphere, in direct contact with air, is subject to intense friction from environmental resistance. Consequently, the distance over which the auxiliary atmosphere can remain tightly packed is extremely limited. After a certain distance, the airflow deviates from the axial direction and diffuses outward, simultaneously reducing the density and uniformity of the airflow. At this point, external gas enters the interior in the form of turbulent flow, disrupting the light-guiding water jet and eliminating the protective effect of the auxiliary atmosphere. The present invention's multiple water-air composite design, which adds an annular water curtain to the existing auxiliary atmosphere, achieves this by adding a greater momentum after the annular water curtain is ejected, as the density of water is much greater than that of gas. This makes it less susceptible to being affected by the surrounding atmosphere and disrupting the jet's shape. Consequently, the annular water curtain offers greater stability and compactness than spraying the auxiliary atmosphere alone, extending the stable spray distance and providing greater isolation from external gases. At the same time, since the annular water curtain does not participate in the thermal processing process, the width of its liquid flow will not affect the processing accuracy, so the effective air isolation protection distance can be greatly extended by appropriately increasing the width of the annular liquid flow.

[0025] The annular water curtain design of the present invention can limit the outward diffusion of the internal auxiliary atmosphere and generate co-directional movement with the auxiliary atmosphere, so it can effectively restrain and maintain the stable flow state of the auxiliary atmosphere, extend the length of the auxiliary atmosphere maintained in a tight state, and thereby simultaneously extend the stable length of the light-guiding water jet in the auxiliary atmosphere.

[0026] The multi-water-air composite water-conducting laser processing method under the annular water curtain composite of the present invention can more effectively remove excess processing heat and cutting residues, so that the obtained incision heat-affected zone will be smaller and the incision quality will be better.

[0027] The multiple water-air composite water-conducting laser processing device of the present invention is simple in design and easy to implement, and has many composite beneficial effects, obvious effects, and good practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG1 is a schematic structural diagram of the present invention.

[0029] FIG2 is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0030] In the following description, specific details such as specific system structures and technologies are provided for illustration rather than limitation to facilitate a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid obstructing the description of the present application with unnecessary details.

[0031] It will be understood that when used in this specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0032] It should also be understood that the terms used in this specification are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in this specification and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0033] The following is a clear and complete description of the technical solutions in the embodiments of the present application in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments of the present application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0034] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0035] The present invention is a composite water-guided laser processing method that sequentially and coaxially composites an auxiliary atmosphere and an annular water curtain outside a light-guiding water jet to form a three-layer structure with the light-guiding water jet as the center, the auxiliary atmosphere, and the annular water curtain inside and outside.

[0036] A water-guided laser processing device in a multiple water-air composite mode, the water-guided laser processing device includes a light-water coupling device 2, an annular water jet device 3, a nozzle 4 and an annular liquid nozzle 5, and an auxiliary atmosphere input gas path 9.

[0037] An auxiliary atmosphere input gas path 9 is provided in the interlayer between the light-water coupling device 2 and the annular water jet device 3. The auxiliary atmosphere input gas path 9 ejects the auxiliary atmosphere through the annular gas nozzle 6 to form an auxiliary airflow layer 8. A nozzle 4 is provided at the lower end of the light-water coupling device 2, and an annular liquid nozzle 5 is provided at the bottom of the annular water jet device 3. The light-water coupling device 2 is used to couple the laser beam 1 with the internal liquid and then eject a single water jet 10 from the nozzle 4. The annular water jet device 3 is used to eject the internal liquid from the annular liquid nozzle 5 to form an annular water curtain 7 surrounding the light-guiding water jet 10, and the annular water curtain 7 covers the auxiliary airflow layer 8.

[0038] Furthermore, the single-channel water jet 10, the auxiliary airflow layer 8 and the annular water curtain 7 are a coaxial composite structure from the inside to the outside, that is, an inside-outside coaxial composite structure under multiple water-air-water modes.

[0039] When laser beam 1 enters light-water coupling device 2, it converges at the inlet of nozzle 4 and couples into a single water jet 10, forming a light-guiding water jet. This light-guiding water jet, along with auxiliary airflow 8 and an annular water curtain 7, is then ejected onto the surface of the workpiece to be processed.

[0040] Furthermore, the annular water jet device 3 is connected to the lower end of the optical-water coupling device 2; by integrating the annular water jet device 3 and the optical-water coupling device 2, space can be saved, and it is more conducive to setting the nozzle 4 and the annular liquid nozzle 5 in a coaxial form. A flange can be set at the lower end of the nozzle 4, and a stable annular water curtain 7 can be formed by the cooperation of the flange and the annular liquid nozzle 5.

[0041] Furthermore, a laser emitting device is provided above the optical-water coupling device 2 for emitting the laser beam 1 into the optical-water coupling device 2 .

[0042] Furthermore, the laser beam 1 is a single energy beam or a composite energy beam. This device can adapt to different types of laser beams and has high versatility. This can be achieved by adding different types of laser emitting devices.

[0043] Furthermore, both the optical-water coupling device 2 and the annular water jet device 3 are equipped with high-pressure water inlets. This arrangement allows for separate control of the hydraulic pressure within the optical-water coupling device 2 and the annular water jet device 3, thereby enabling independent regulation of the light-guiding water jet and the annular water curtain jet. The high-pressure water inlets of the optical-water coupling device 2 and the annular water jet device 3 can be placed on the same side, facilitating installation and providing a more rational layout for the high-pressure water piping.

[0044] A water-guided laser processing method in a multiple water-air composite mode, the water-guided laser processing method comprising the following steps:

[0045] Step 1: ejecting water in the water-guided laser processing device at high speed under pressure to form a single water jet;

[0046] Step 2: Coaxially compound an auxiliary atmosphere to enclose the single water jet formed in step 1, and coaxially compound another annular water curtain outside the auxiliary atmosphere to form an internal and external coaxial composite structure under multiple water-air-water modes;

[0047] The auxiliary atmosphere is ejected coaxially and in the same direction as the single-channel water jet inside it, and its function is to enable the single-channel water jet to maintain laminar flow characteristics and extend the stable length of the jet, and to isolate the single-channel water jet from contact with the annular water curtain, so that the single-channel water jet maintains a complete liquid-gas boundary film, thereby allowing the laser beam to maintain total reflection propagation in the single-channel water jet.

[0048] Step 3: Couple the high-energy laser beam into the single-channel water jet formed in step 1 to form a light-guiding water jet, and spray it onto the surface of the workpiece to be processed together with the auxiliary atmosphere and the annular water curtain.

[0049] The annular water curtain envelops the auxiliary atmosphere and does not participate in the heat treatment process. Its main function is to isolate the influence of the external gas flow field on the auxiliary atmosphere, limit the outward diffusion of the internal auxiliary atmosphere, and generate co-directional movement with the auxiliary atmosphere, thereby reducing the environmental friction resistance of the auxiliary atmosphere during the injection. Therefore, it can effectively restrain and maintain the stable flow state of the auxiliary atmosphere, enhance the protective effect of the auxiliary atmosphere on the single-channel water jet, and further extend the stable length of the jet.

[0050] Furthermore, the diameter of the single-channel water jet in step 1 is 10-600 μm, and the water pressure ranges from 0-100 MPa.

[0051] Furthermore, the auxiliary atmosphere gas pressure in step 2 is 0.1-10 MPa.

[0052] The auxiliary atmosphere provided in this manner can envelop the single-channel water jet 10 , and even when the annular water curtain 7 is slightly offset toward the single-channel water jet 10 , a good and normal cutting effect can still be ensured.

[0053] Furthermore, the water in the light-water coupling device and the annular water jet device includes pure water or distilled water or other liquids that meet the light guiding requirements.

Claims

1. A water-conducting laser processing device in multiple water-air composite modes, characterized in that: The water-conducting laser processing device comprises a light-water coupling device (2), an annular water jet device (3), a nozzle (4), an annular liquid nozzle (5) and an auxiliary atmosphere input gas path (9). An auxiliary atmosphere input gas path (9) is provided in the interlayer between the light-water coupling device (2) and the annular water jet device (3), and the auxiliary atmosphere input gas path (9) ejects the auxiliary atmosphere through an annular gas nozzle (6) to form an auxiliary airflow layer (8). A nozzle (4) is provided at the lower end of the light-water coupling device (2), and an annular liquid nozzle (5) is provided at the bottom of the annular water jet device (3). The light-water coupling device (2) is used to couple the laser beam (1) with the internal liquid and then eject a single water jet (10) from the nozzle (4). The annular water jet device (3) is used to eject the internal liquid from the annular liquid nozzle (5) to form an annular water curtain (7) surrounding the light-guiding water jet (10), and the annular water curtain (7) envelops the auxiliary airflow layer (8).

2. The water-conducting laser processing device according to claim 1, characterized in that: The single-channel water jet (10), the auxiliary airflow layer (8) and the annular water curtain (7) are a coaxial composite structure from inside to outside, that is, an inside-outside coaxial composite structure under multiple water-air-water modes.

3. The water-conducting laser processing device according to claim 1, characterized in that: The annular water jet device (3) is connected to the lower end of the light-water coupling device (2).

4. The water-conducting laser processing device in multiple water-air composite modes according to claim 1, characterized in that: A laser emitting device is arranged at the upper end of the light-water coupling device (2) for emitting a laser beam (1) into the light-water coupling device (2).

5. The water-conducting laser processing device according to claim 1, characterized in that: The laser beam (1) is a single energy beam or a composite energy beam.

6. The water-conducting laser processing device according to claim 1, characterized in that: The optical-water coupling device (2) and the annular water jet device (3) are both provided with high-pressure water inlets.

7. A water-conducting laser processing method in multiple water-air composite modes, characterized in that: The water-conducting laser processing method comprises the following steps: Step 1: spraying water in the water-conducting laser processing device as claimed in claim 1 at high speed under pressure to form a single water jet; Step 2: Coaxially compound an auxiliary atmosphere to wrap the single water jet formed in step 1, and coaxially compound another annular water curtain outside the auxiliary atmosphere to form a multiple water-air-water mode The internal and external coaxial composite structure; Step 3: Couple the high-energy laser beam into the single-channel water jet formed in step 1 to form a light-guiding water jet, and spray it onto the surface of the workpiece to be processed together with the auxiliary atmosphere and the annular water curtain.

8. The water-conducting laser processing method according to claim 1, characterized in that: The single-channel water jet in step 1 has a diameter of 10-600 μm and a water pressure range of 0-100 MPa.

9. The water-conducting laser processing method according to claim 1, characterized in that: The auxiliary atmosphere gas pressure in step 2 is 0.1-10 MPa.

10. The water-conducting laser processing method according to claim 1, characterized in that: The water in the light-water coupling device and the annular water jet device includes pure water or distilled water or other liquids meeting the light guiding requirements.

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