CN114717641A - Runner surface aftertreatment device in laser powder bed melting forming piece - Google Patents

Abstract

The invention discloses a post-treatment device for the surface of an inner runner of a laser powder bed fused forming piece, a workpiece to be treated is horizontally fixed by a clamp, a linear motion mechanism is arranged at one end of one side of the clamp, which is positioned at the workpiece to be treated, the other end of the clamp, which is positioned at the other end of the workpiece to be treated, is provided with a peristaltic pumping system, a bidirectional liquid conveying pipe and a wire electrode are adopted, polishing liquid conveyed by the liquid conveying pipe acts on the surface of the wire electrode, point discharge occurs at microscopic and macroscopic bulges of the workpiece, thereby achieving the treatment of the smoothness of the inner surface of the workpiece, the area of the pipe capable of being polished is greatly reduced by adopting the bidirectional structure arrangement, a polishing passage is provided for the inner runner to be processed by utilizing the polishing liquid, a polishing passage is provided for the workpiece with the cooling liquid, the polishing of the workpieces with different lengths of the inner runner to be processed can be realized, the wire electrode passes through the inner runner of the workpiece to be processed, only the inner surface of the inner flow channel of the workpiece participates in the reaction, the outer surface of the workpiece is not contacted with the polishing solution, and the structure is simple.

Description

A post-processing device for the surface of the inner flow channel of a laser powder bed fusion forming part

technical field

The invention belongs to the technical field of post-processing of workpieces, and in particular relates to a post-processing device for the surface of the inner flow channel of a laser powder bed fusion forming part.

Background technique

With the development of industry, the requirements for the surface roughness of metal products are getting higher and higher. The application of polishing technology can not only improve the appearance of the product, but also improve the corrosion resistance and wear resistance of the material surface. Therefore, choosing the appropriate polishing method and polishing process is an important means to improve the quality of the product. At present, the commonly used polishing methods at home and abroad are: mechanical polishing, chemical polishing, electrolytic polishing, ultrasonic polishing, magnetic polishing and so on. However, some of the above polishing methods not only rely on the manual labor of the polishing workers, but also the metal powder produced during the polishing process will seriously affect the health of the polishing workers. The desired high quality, but the processing efficiency is low, and the precision and consistency of the product are poor; there are also some polishing methods that use a certain concentration of acid or alkali, some of which are chemicals that pollute the environment, and waste generated during the polishing process. The liquid is difficult to handle, the polishing cost is high, and the effect is limited.

As an interdisciplinary frontier research field, plasma technology has a wide range of applications in materials, energy, astronomy, chemical engineering, bioengineering, etc. A series of new technologies and new processes have been developed in the fields of processing and surface treatment. The traditional plasma polishing technology excites the plasma under vacuum, low pressure or normal pressure, and uses the active particles in the plasma to chemically react with the surface material particles to generate volatile substances and remove the surface material. It is mainly used in optical components. Most of the processing objects are semiconductor materials.

At present, there is also a small amount of research on inner hole polishing by electrolyte plasma processing technology. According to the invention patent with the application number CN107557853A titled "Small hole polishing device and processing method", the problem of inner hole polishing is solved by electrolyte plasma polishing, but the polished inner hole The diameter is larger, and the polishing range of the pipe diameter in "Small Hole Polishing Device and Processing Method" is DN20mm-DN50mm; the structure of the fixed part of the nozzle is complex, and it needs to be fixed by an insulating clamp, and the internal cathode conducting tube has no insulation treatment. When dealing with thin tubes with small inner hole size, short circuit phenomenon is easy to occur. For example, when the processing aperture is less than 5mm, the insulation distance between the metal workpiece and the conductive metal tube is removed by 500mm, and the size of the conductive metal tube is much less than 5mm. If it is small, the discharge will directly occur, thereby breaking down the thin tube), so it cannot be used for inner flow channel polishing with a diameter of less than 5mm. The pipes polished by these two inner hole polishing equipments need to be vertically fixed on the equipment hanger. During polishing, the metal workpiece and the electrode wire need to be directly immersed in the polishing solution, so there are certain restrictions on the length of the inner flow channel thin pipe for polishing. It is not suitable for polishing the inner flow channel with small hole diameter and large length.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a post-processing device for the surface of the inner flow channel of a laser powder bed fusion forming part, so as to overcome the deficiencies of the prior art.

A post-processing device for the surface of the inner flow channel of a laser powder bed fusion forming part, comprising a fixture for fixing the workpiece to be processed, the workpiece to be processed is fixed horizontally by the fixture, and one side of the fixture is located at one end of the workpiece to be processed. There is a linear motion mechanism, and an electrode wire is fixed on the linear motion mechanism. The electrode wire can be coaxially arranged in the workpiece to be processed. The other side of the fixture is located at the other end of the workpiece to be processed. A peristaltic pumping system is installed. One end is connected with a constant temperature heating box, and the other end of the peristaltic pumping system is connected with an infusion tube. The infusion tube can enter the workpiece to be processed from the other end of the workpiece to be processed. The workpiece to be processed is connected to the positive pole of the power supply, and the electrode wire is connected to the negative pole of the power supply.

Preferably, a workbench is provided at the bottom of the fixture.

Preferably, a lifting mechanism is fixed at the bottom of the linear motion mechanism.

Preferably, a protective cover is provided on the outer ring of the clamp, the linear motion mechanism and the peristaltic pumping system.

Preferably, the bottom of the workbench is provided with a water collecting tank, and the water collecting tank is connected to the constant temperature heating box through the infusion pipeline.

Preferably, a plurality of electrode wires are fixed on the linear motion mechanism.

Preferably, the output end of the peristaltic pumping system is plugged with a plurality of infusion tubes.

Preferably, a guide frame is arranged on the worktable, and a plurality of through holes are arranged on the guide frame.

Preferably, the lifting mechanism adopts an X-type lift.

Preferably, an insulating layer is provided between the fixture and the workbench.

Compared with the prior art, the present invention has the following beneficial technical effects:

The invention is a post-processing device for the surface of the inner flow channel of a laser powder bed melting and forming part. The workpiece to be processed is fixed horizontally by a clamp, and a linear motion mechanism is arranged on one side of the clamp at one end of the workpiece to be treated. An electrode wire is fixed, and the electrode wire can be coaxially arranged in the workpiece to be treated. The other side of the fixture is located at the other end of the workpiece to be treated, and a peristaltic pumping system is installed. One end of the peristaltic pumping system is connected with a constant temperature heating box. The other end of the feeding system is connected with an infusion tube, which can enter the workpiece from the other end of the workpiece to be processed. The workpiece to be processed is connected to the positive pole of the power supply, and the electrode wire is connected to the negative pole of the power supply. The polishing liquid conveyed by the tube acts on the surface of the electrode wire, and a plasma gas layer is formed on the surface of the workpiece through the vapor-liquid plasma generation technology, and tip discharge occurs at the microscopic and macroscopic protrusions of the workpiece, so as to achieve the treatment of the inner surface finish of the workpiece. The two-way structure greatly reduces the area of the pipeline that can be polished. By partially polishing the electrode wire, the polishing liquid is used to provide cooling liquid for the inner flow channel to be processed and also provide polishing channels, which can realize the polishing of workpieces with inner flow channels of different lengths. The wire passes through the inner flow channel of the workpiece to be processed, only the inner surface of the inner flow channel of the workpiece participates in the reaction, the outer surface of the workpiece does not contact the polishing liquid, and the structure is simple.

Preferably, a lifting mechanism is used to control the electrode wire, and the lifting mechanism can make the electrode wire move up and down while moving in a straight line, so as to ensure that the electrode wire can enter the inner flow channel of complex irregular parts, and polish the complex inner passage. , under the premise of not affecting the performance of the part, the flow channel structure is polished, and the invention combines the electrolyte plasma polishing to polish the inner surface of the part, which greatly improves the polishing speed of the inner surface of the part and realizes the polishing of irregular inner surface channels.

Preferably, an insulating layer is provided between the fixture and the worktable to ensure safe electricity consumption during the polishing process.

Description of drawings

FIG. 1 is a front view of an inner flow channel surface post-processing device in an embodiment of the present invention.

FIG. 2 is a three-dimensional structural diagram of an inner flow channel surface post-processing device according to an embodiment of the present invention.

FIG. 3 is a three-dimensional structural view of the installation of the lifting mechanism and the linear motion mechanism in the embodiment of the present invention.

FIG. 4 is a schematic diagram of an enlarged structure for installing a workpiece to be processed in an embodiment of the present invention.

FIG. 5 is a diagram of unpolished parts in the embodiment of the present invention.

FIG. 6 is a diagram of parts after polishing using the device of the present invention in the embodiment of the present invention.

In the figure, 1. Workbench, 2. Lifting mechanism, 3. Linear motion mechanism, 4. Fixture, 5. Workpiece to be processed, 6. Peristaltic pumping system, 7. Constant temperature heating box, 8. Infusion tube, 9. Electrode wire, 10, infusion pipeline, 11, water collecting tank, 12, water pump, 13, control valve, 14, insulating layer, 15, protective cover, 16, guide frame.

Detailed ways

In order to make those skilled in the art better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only Embodiments are part of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Example

As shown in FIG. 1 , a post-processing device for the inner flow channel surface of a laser powder bed fusion forming part of the present invention includes a fixture 4 for fixing the workpiece 5 to be processed, and the workpiece 5 to be processed is horizontally fixed by the fixture 4. One side of the fixture 4 is located at one end of the workpiece 5 to be processed, and a linear motion mechanism 3 is provided. The linear motion mechanism 3 is fixed with an electrode wire 9, and the electrode wire 9 can be coaxially arranged in the workpiece 5 to be processed. One side is positioned at the other end of the workpiece 5 to be processed and is provided with a peristaltic pumping system 6, one end of the peristaltic pumping system 6 is connected with a constant temperature heating box 7, the constant temperature heating box 7 is used for heating polishing liquid, and the other end of the peristaltic pumping system 6 is connected There is an infusion tube 8, and the infusion tube 8 can enter the workpiece 5 to be treated from the other end of the workpiece to be treated. During polishing, the workpiece to be treated 5 is connected to the positive pole of the power supply, and the electrode wire 9 is connected to the negative pole of the power supply. The present invention adopts a bidirectionally arranged infusion tube. 8 and electrode wire 9, the polishing liquid delivered by the infusion tube 8 acts on the surface of the electrode wire 9, and a plasma gas layer is formed on the surface of the workpiece through the vapor-liquid plasma generation technology, and tip discharge occurs at the microscopic and macroscopic protrusions of the workpiece, thereby achieving For the treatment of the inner surface smoothness of the workpiece, the bidirectional structure is adopted, which greatly reduces the area of the pipeline that can be polished. Through local polishing of the electrode wire, the polishing liquid is used to provide the cooling liquid for the inner flow channel to be processed and the polishing passage, which can realize different lengths. The workpiece in the inner flow channel is polished, and the electrode wire is passed through the inner flow channel of the workpiece to be processed. Only the inner surface of the inner flow channel of the workpiece participates in the reaction, and the outer surface of the workpiece is not in contact with the polishing liquid, and the structure is simple.

As shown in FIG. 1 , the fixture 4 is fixedly installed on the workbench 1 , and an insulating layer 14 is provided between the fixture 4 and the workbench 1 to ensure the safety of electricity use during the polishing process.

A lifting mechanism 2 is fixed at the bottom of the linear motion mechanism 3, and the lifting mechanism 2 is fixed on the worktable 1 to adjust the running height of the linear motion mechanism 3. The present invention adopts the lifting mechanism 2 to carry out a flexible design of the electrode wire 9. The mechanism 2 can make the electrode wire 9 move up and down while moving in a straight line, to ensure that the electrode wire 9 can enter the inner flow channel of complex irregular parts, polish the complex inner passage, and convection without affecting the performance of the part. Polishing the inner surface of the part combined with the electrolyte plasma polishing, greatly improves the polishing speed of the inner surface of the part and realizes the polishing of irregular inner surface channels.

As shown in FIG. 1 , the lift mechanism 2 used in the present invention is an X-type lift, which aims to provide stable vertical lift drive, and other structures capable of linear lift drive can also be used.

During the working process, the workpiece 5 to be treated is connected to the positive electrode of the power supply, as an anode, and the electrode wire 9 is used as a cathode to pass through the inner flow channel of the workpiece and discharge the surface of the flow channel, and form a plasma gas layer on the surface of the workpiece through the vapor-liquid plasma generation technology. The tip discharge occurs at the micro and macro protrusions of the workpiece, so as to achieve the treatment of the inner surface finish of the workpiece.

The polishing liquid used in the present invention is a low-concentration neutral salt solution (the neutral salt solution can be directly discharged), and the waste water generated in the polishing process only contains the metal thrown away by the plasma, the pollution is particularly small, the processing cost is low, and it cannot be processed for mechanical polishing. For parts with complex shapes, electrolytic plasma polishing can obtain a machined surface with good consistency. The electrolyte plasma polishing efficiency of the invention can reduce the average roughness per minute of the same position of the workpiece by 1um (original roughness Ra=about 5um), and the polishing roughness satisfies: Ra<1um.

As shown in Figure 1, there are multiple electrode wires fixed on the linear motion mechanism, which can process multiple flow channels at the same time, which greatly improves the efficiency of the surface treatment of the flow channel of the workpiece. The electrode wire connected to the negative electrode of the power supply is fixed at one end of the linear motion mechanism. The electrode wire does not need a clamp for fixing, but only needs to be fixed on the negative electrode of the power supply of the moving part of the linear motion mechanism. The part of the electrode wire between the layers and the inner flow channel of the workpiece to be polished form a polishing channel environment. Through local polishing of the electrode wire, the polishing liquid is used to provide the cooling liquid for the inner flow channel to be processed and the polishing channel, so that the inner flow channels of different lengths can be realized. For workpiece polishing, the electrode wire is passed through the inner flow channel of the workpiece to be processed, only the inner surface of the inner flow channel of the workpiece participates in the reaction, the outer surface of the workpiece does not contact the polishing liquid, and the structure is simple.

As shown in FIG. 2 , the outer ring of the fixture 4 , the linear motion mechanism 3 and the peristaltic pumping system 6 is provided with a protective cover 15 , and the protective cover 15 is provided with a movable transparent observation window, which can be observed during the polishing process.

As shown in Figure 3, the bottom of the workbench 1 is provided with a water collecting tank 11, and the water collecting tank 11 is connected to the constant temperature heating box 7 through the infusion pipeline 10 to realize the recycling of the polishing liquid; the peristaltic pumping system 6 supplies each inner flow channel The polishing liquid is pumped, and the polishing liquid in the flow channel forms a plasma gas layer on the inner surface of the workpiece flow channel due to the action of cathodic and anode discharge, and discharges the micro and macro protrusions on the inner surface of the workpiece, so as to achieve the treatment of the surface finish of the workpiece.

The constant temperature heating box 7 is connected to the water pump 12 and the water collecting tank 11 through the infusion pipeline 10. The infusion pipeline 10 is provided with a control valve 13. The constant temperature heating box 7 heats the polishing liquid contained therein and maintains a constant temperature state. The workpiece 5 to be processed is fixed on the workbench 1 using a fixture 4, and the outlet end of the peristaltic pumping system 6 is connected to a plurality of infusion pipes 8, which are connected to the inner flow channel port of the workpiece 5 to be polished. According to the size of the workpiece 5 to be processed, the height of the lifting mechanism 2 is adjusted to suit the height of the flow channel in the workpiece. The electronic control system controls the movement of the peristaltic pumping system 6 and the linear motion mechanism 3 according to the polishing control instructions through the transmission line. The polishing electrode wire 9 is connected to the negative pole of the power supply, and the workpiece 5 is connected to the positive pole of the power supply.

As shown in FIG. 4 , the worktable 1 is provided with a guide frame 16 , a plurality of through holes are arranged on the guide frame 16 , each through hole is provided with an electrode wire 9 , and the guide frame 16 is used to guide the plurality of electrode wires 9 Alignment, the peristaltic pumping system 6 adopts multiple single pumps, and the output ends are correspondingly connected to multiple infusion pipes 8. During the working process, the flow rate of the polishing liquid in each inner flow channel can be individually controlled and adjusted.

The fixture 4 is fixed on the worktable 1, and an insulating layer 14 is arranged between the two. Different fixtures are provided according to workpieces of different sizes.

The linear motion mechanism 3 is installed on the lifting mechanism 2, which is convenient to adapt to workpieces of different diameters and adjust the height of the electrode wire during the working process.

The electrode wire 9 is fixed on the linear motion mechanism 3, which facilitates the linear uniform movement of the electrode wire 9 during the working process.

Specific polishing process:

Use the fixture 4 to fix the workpiece 5 to be processed on the workbench 1;

The lifting mechanism 2 adjusts the height of the linear motion mechanism 3 to make the electrode wire 9 adapt to the height of the flow channel in the workpiece;

The electrode wire 9 is connected to the negative pole of the power supply as a cathode, and the workpiece 5 is connected to the positive pole of the power supply as an anode;

Control the movement of the peristaltic pumping system 6 and the linear motion mechanism 3 according to the polishing control instruction;

The electrode wire 9 is used as a cathode to discharge on the surface of the inner flow channel of the workpiece, and a plasma gas layer is formed on the surface of the workpiece through the vapor-liquid plasma generation technology, and tip discharge occurs at the microscopic and macroscopic protrusions of the workpiece, so as to achieve the inner surface finish of the workpiece. deal with.

As shown in FIG. 6 , by using the laser powder bed fusion forming part inner flow channel surface post-processing device of the present invention, the polishing of the parts with a size of 2 cm in diameter to 60 cm in diameter and a length of 100 cm, and the material is 304 stainless steel, is realized, as shown in FIG. 5 . The part diagram before polishing, Figure 6 is the part after polishing (diameter 5cm, length 30cm), the surface of the part after polishing is smooth, and the roughness is obviously reduced.

Claims (10)

1. A post-processing device for the inner flow channel surface of a laser powder bed fusion forming part, characterized in that it comprises a fixture (4) for fixing the workpiece (5) to be processed, and the workpiece (4) to be processed is fixed by the fixture (4). 5) Fixed horizontally, a linear motion mechanism (3) is arranged on one end of the workpiece (5) to be processed on one side of the fixture (4), and an electrode wire (9) is fixed on the linear motion mechanism (3), and the electrode wire ( 9) It can be coaxially inserted into the workpiece (5) to be processed, and the other side of the fixture (4) is located at the other end of the workpiece (5) to be processed with a peristaltic pumping system (6), and the peristaltic pumping system ( 6) One end is connected with a constant temperature heating box (7), the other end of the peristaltic pumping system (6) is connected with an infusion tube (8), and the infusion tube (8) can enter the workpiece to be processed from the other end of the workpiece to be processed (5). (5) Inside, the workpiece to be processed (5) is connected to the positive pole of the power supply, and the electrode wire (9) is connected to the negative pole of the power supply. 2 . The post-processing device for the inner flow channel surface of a laser powder bed fusion forming part according to claim 1 , wherein a worktable ( 1 ) is provided at the bottom of the fixture ( 4 ). 3 . 3 . The post-processing device for the inner flow channel surface of a laser powder bed fusion forming part according to claim 1 , wherein a lifting mechanism ( 2 ) is fixed at the bottom of the linear motion mechanism ( 3 ). 4 . 4. A laser powder bed fusion forming part inner flow channel surface post-processing device according to claim 1, characterized in that the clamp (4), the linear motion mechanism (3) and the peristaltic pumping system (6) The outer ring is provided with a protective cover (15). 5 . The post-processing device for the inner flow channel surface of a laser powder bed fusion forming part according to claim 2 , wherein the bottom of the worktable ( 1 ) is provided with a water collecting groove ( 11 ), and the water collecting groove ( 11 ) passes through the water collecting groove ( 11 ). 6 . The infusion pipeline (10) is connected to the constant temperature heating box (7). 6 . The post-processing device for the inner flow channel surface of a laser powder bed fusion forming part according to claim 1 , wherein a plurality of electrode wires ( 9 ) are fixed on the linear motion mechanism ( 3 ). 7 . 7 . The post-processing device for the inner flow channel surface of a laser powder bed fusion forming part according to claim 6 , wherein the output end of the peristaltic pumping system ( 6 ) is plugged with a plurality of infusion tubes ( 8 ). 8 . 8 . The post-processing device for the inner flow channel surface of a laser powder bed fusion forming part according to claim 2 , wherein a guide frame ( 16 ) is arranged on the worktable ( 1 ), and a guide frame ( 16 ) is arranged on the guide frame ( 16 ). There are multiple through holes. 9 . The post-processing device for the inner flow channel surface of a laser powder bed fusion forming part according to claim 3 , wherein the lifting mechanism ( 2 ) adopts an X-type lift. 10 . 10 . The post-processing device for the inner flow channel surface of a laser powder bed fusion forming part according to claim 2 , wherein an insulating layer ( 14 ) is provided between the fixture ( 4 ) and the worktable ( 1 ). 11 .

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