Directional droplet flow assisted micro-electrolysis wire cutting machining method

Abstract

The invention discloses a directional droplet flow assisted micro electrolytic wire cutting machining method. Before machining is started, a workpiece and a wire electrode are clamped in an electrolyte tank and connected with a pulse power supply; a control system of the numerical control machine tool is used for enabling the line electrode and the workpiece to be in a machining gap position; turning on a switch of the micro-droplet flow spray head to spray electrolyte, so that micro-droplet flow formed by the electrolyte is sprayed to the workpiece to wet the whole surface of the workpiece and the machining gap area, and when micro-droplets form micro-liquid flow along the surface of the workpiece and flow through the machining area, the micro-liquid flow downwards flows along the line electrode through the gravity of the micro-droplet flow and the adhesive force of the liquid flow; according to the invention, the micro-liquid flow continuously supplied to the machining gap area is utilized to realize the updating of the electrolyte and the removal of the product in the machining gap area, so that the machining stability and the machining precision are improved, the operation is simple, the operability is strong, and the like.

Description

Technical Field

[0001] The invention relates to the technical field of micro-electrolytic wire cutting processing, and in particular to a directional droplet flow assisted micro-electrolytic wire cutting processing method. Background Art

[0002] Micro-electrolytic machining is a technology that dissolves workpieces in trace amounts based on the principle of electrochemical ion removal. The workpieces for electrolytic machining are usually in the nanometer to micrometer range, and the wire electrodes are usually in the nanometer to micrometer range. Theoretically, it can achieve atomic-level machining accuracy, and has the advantages of high efficiency, low cost, no relation to material hardness, and no machining stress. It has great development potential in micro-machining. Micro-electrolytic wire cutting is a new type of micro-electrolytic machining technology that combines the electrolytic principle with the wire cutting form. Since the wire electrode has no loss, a micrometer-diameter metal wire can be used as the electrode to machine a few micrometers of slit.

[0003] Existing micro-electrolytic cutting processes are all immersed processes, that is, the wire electrode and the workpiece are immersed in the electrolyte in the electrolyte tank. Since the kerf of micro-electrolytic wire cutting is too narrow, it is difficult for the electrolyte to enter the processing gap and cannot be updated in time, which reduces the electrolytic reaction speed. At the same time, the electrolytic products are difficult to discharge from the processing gap. The accumulation in the kerf will cause the composition and conductivity of the electrolyte to change, affecting the stability of the electrolytic processing, and even causing a short circuit and terminating the processing. Especially for the cutting of thick workpieces, as the thickness of the workpiece increases, the deeper and narrower the kerf, the more difficult it is to remove the electrolytic products and the more difficult it is to update the electrolyte.

[0004] Patent publication number CN108788352B discloses a wire electrode workpiece different speed compound motion micro-electrolytic wire cutting processing method, the wire electrode and the workpiece perform different speed relative cutting motion in the processing direction, and the static electrolyte flows in the opposite direction and quickly flushes the product in the gap; the wire electrode and the workpiece perform alternating reciprocating motion perpendicular to the processing direction to assist mass transfer in the gap; the composite motion in different directions is used to realize the position change of the processing area, drive the electrolyte in the processing gap to quickly update and flow, and perform differential motion micro-electrolytic wire cutting processing under efficient mass transfer conditions; However, since the workpieces and wire electrodes for micro-electrolytic machining are usually in the nanometer to micrometer range, the required equipment requires extremely high precision, and the wire electrode is easy to deform. The wire electrode may be easily deformed due to large-scale disturbances in the electrolyte and large-scale jitters in the wire electrode, thereby affecting the machining stability and accuracy, and the operation is complicated and the operability is low. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the existing defects and provide a directional droplet flow-assisted micro-electrolytic wire cutting processing method, in which the micro-liquid flow formed by the micro-droplet flow continuously flows to the processing gap to realize the renewal of the electrolyte and the removal of products in the processing gap area, accelerate the diffusion and migration rate of metal ions on the processing surface, ensure the complete discharge of insoluble products, enhance the mass transfer efficiency, accelerate the material removal rate, significantly improve the processing stability, processing quality and processing efficiency, thereby improving the processing conditions; the electrolyte has little interference with the wire electrode, and can prevent the wire electrode from being deformed due to a large range of disturbances caused by the electrolyte or a large range of jitters caused by the wire electrode, thereby affecting the processing stability and processing accuracy. The structure is simple, the processing cost is low, the operation is simple, the operability is strong, and the problems in the background technology can be effectively solved.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a method for assisted micro-electrolytic wire cutting processing with directional droplet flow, wherein the auxiliary use of the method in micro-electrolytic wire cutting processing is divided into two stages: before the start of processing and during the processing; Before the start of processing: clamp the workpiece and the wire electrode in the electrolyte tank, and connect the workpiece to the positive electrode of the pulse power supply, and connect the wire electrode to the negative electrode of the pulse power supply; use the control system of the CNC machine tool to drive the wire electrode or the workpiece to move, so that the wire electrode and the workpiece are in the processing gap position; turn on the switch of the micro-droplet flow nozzle to spray the electrolyte, adjust the position and angle of the micro-droplet flow nozzle to spray the electrolyte, so that the micro-droplet flow formed by the electrolyte is sprayed on the workpiece to wet its entire surface, and continue to spray the micro-droplet flow to wet the processing gap area with the electrolyte until the micro-droplets form a micro-liquid flow along the surface of the workpiece and flow through the processing area, and the gravity of the micro-droplet flow and the adhesion of the liquid flow make it flow downward along the wire electrode; During the processing: start the pulse power supply, the micro-droplet flow nozzle continuously sprays micro-droplet flow, so that the micro-liquid flow formed by the micro-droplet flow continuously flows to the processing gap, the wire electrode performs micro-electrolytic cutting processing on the workpiece, and the electrolyte in the processing gap area is updated and the product is removed by continuously supplying micro-liquid flow to the processing gap area. The control system of the CNC machine tool drives the wire electrode or the workpiece to move along the cutting path until the processing is completed.

[0007] Furthermore, the pulse power supply used in the micro-electrolytic wire cutting process is a nanosecond-level ultra-short pulse power supply.

[0008] Furthermore, a micro-droplet flowmeter and a booster device are provided on the liquid inlet pipe connected to the micro-droplet flow nozzle. During the process of spraying liquid by the micro-droplet flow nozzle, the spraying flow and speed can be adjusted by the micro-droplet flowmeter, and the injection pressure of the micro-droplet flow nozzle can be increased by the booster device.

[0009] Compared with the prior art, the invention has the following beneficial effects: the directional droplet flow assisted micro-electrolytic wire cutting processing method, (1) The directional droplet flow assisted micro-electrolytic wire cutting processing method of the present invention first sprays electrolyte onto the surface of the workpiece through a micro-droplet flow nozzle to wet the workpiece and the processing gap area until the micro-droplets form a micro-liquid flow along the surface of the workpiece and flow through the processing area. The micro-droplet flow is caused to flow downward along the wire electrode by gravity and liquid adhesion, so that the micro-liquid flow formed by the micro-droplet flow continues to flow toward the processing gap. The wire electrode performs micro-electrolytic cutting processing on the workpiece, and the electrolyte in the processing gap area is renewed and the product is removed by continuously supplying the micro-liquid flow to the processing gap area.

[0010] (2) The directional droplet flow assisted micro-electrolytic wire cutting processing method of the present invention utilizes the micro-liquid flow formed by the micro-droplet flow to continuously flow to the processing gap area, thereby accelerating the diffusion and migration rate of metal ions on the processing surface, ensuring the complete discharge of insoluble products, enhancing the mass transfer efficiency, accelerating the material removal rate, and significantly improving the processing stability, processing quality and processing efficiency, thereby improving the processing conditions.

[0011] (3) The directional droplet flow assisted micro-electrolytic wire cutting processing method of the present invention utilizes the micro-liquid flow formed by the micro-droplet flow to continuously flow to the processing gap area, and only generates bubbles at the processing gap position during electrolytic processing. The bubbles generated in the processing gap float upward into the air, thereby preventing the bubbles from adhering to the workpiece and the wire electrode surface and affecting the processing accuracy.

[0012] (4) The directional droplet flow assisted micro-electrolytic wire cutting processing method of the example of the present invention utilizes the micro-liquid flow formed by the micro-droplet flow to continuously flow to the processing gap area. The electrolyte has little interference with the wire electrode, which can prevent the wire electrode from being deformed due to a large-scale disturbance of the electrolyte or a large-scale jitter of the wire electrode, thereby affecting the processing stability and processing accuracy. It has a simple structure, low processing cost, simple operation and strong operability. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of the structure when the micro-droplets of the present invention wet the entire surface of the workpiece; Figure 2 It is a structural schematic diagram of the present invention when the micro-droplets form micro-liquid flows along the surface of the workpiece and flow through the processing area; Figure 3 This is a working principle diagram of the present invention when in use; Figure 4 It is a comparison diagram of the product and bubble tolerance conditions of the present invention and the prior art immersion micro-electrolytic cutting process.

[0014] In the figure: 1. workpiece; 2. wire electrode; 3. micro-droplet flow nozzle; 4. electrolyte tank; 5. micro-droplet flowmeter; 6. booster device; 7. pulse power supply. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work are within the scope of protection of the present invention. Example

[0016] See also Figure 1-4 , the present invention provides a technical solution: a directional droplet flow assisted micro-electrolytic wire cutting processing method, the auxiliary use of this method in micro-electrolytic wire cutting processing is divided into two links before the start of processing and during the processing; Before the start of processing: clamp the workpiece 1 and the wire electrode 2 in the electrolyte tank 4, and connect the workpiece 1 to the positive electrode of the pulse power supply 7, and the wire electrode 2 to the negative electrode of the pulse power supply 7, and the pulse power supply 7 is a nanosecond ultra-short pulse power supply; use the control system of the CNC machine tool to drive the wire electrode 2 or the workpiece 1 to move, so that the wire electrode 2 and the workpiece 1 are in the processing gap position; turn on the switch of the micro-droplet flow nozzle 3 to spray the electrolyte, adjust the position and angle of the micro-droplet flow nozzle 3 to spray the electrolyte, so that the micro-droplet flow formed by the electrolyte is sprayed on the workpiece 1 to wet its entire The surface of the workpiece 1 is continuously sprayed with micro-droplets to wet the processing gap area with the electrolyte; until the micro-droplets form a micro-liquid flow along the surface of the workpiece 1 and flow through the processing area, the micro-droplet flow is caused to flow downward along the wire electrode 2 by the gravity of the micro-droplet flow and the adhesion of the liquid flow; after the micro-droplet flow wets the workpiece 1 and the processing gap, the workpiece 1 and the wire electrode 2 are in a state of being "wrapped" by the electrolyte, providing electrolytic processing conditions, and after wetting the workpiece 1, it is convenient for the micro-droplets to form a micro-liquid flow along the surface of the workpiece 1, and a micro-droplet flowmeter 5 and a booster device 6 are provided on the liquid inlet pipe connected to the micro-droplet flow nozzle 3; During the processing: the pulse power supply 7 is started, the micro-droplet flow nozzle 3 continuously sprays micro-droplet flow, so that the micro-liquid flow formed by the micro-droplet flow continuously flows to the processing gap, and the wire electrode 2 performs micro-electrolytic cutting processing on the workpiece 1, and the renewal of the electrolyte in the processing gap area and the removal of products are achieved by continuously supplying the micro-liquid flow to the processing gap area; and in the electrolytic processing, bubbles are only generated at the processing gap position, and the bubbles generated in the processing gap float upward into the air to prevent the bubbles from adhering to the surface of the workpiece 1 and the wire electrode 2, affecting the processing accuracy; the control system of the CNC machine tool drives the wire electrode 2 or the workpiece 1 to move along the cutting path until the processing is completed.

[0017] In the two links before the processing starts and during the processing, the spraying flow rate and speed of the micro-droplet flow nozzle 3 can be adjusted by the micro-droplet flow meter 5, and the injection pressure of the micro-droplet flow nozzle 3 can be increased by the booster device 6.

[0018] The directional droplet flow assisted micro-electrolytic wire cutting processing method disclosed in this embodiment first sprays electrolyte onto the surface of the workpiece 1 through the micro-droplet flow nozzle 3 to wet the workpiece 1 and the processing gap area, until the micro-droplets form a micro-liquid flow along the surface of the workpiece 1 and flow through the processing area, and then the micro-droplet flow is caused to flow downward along the wire electrode 2 by the gravity and adhesion of the liquid flow. After the micro-droplet flow wets the workpiece 1 and the processing gap area, the workpiece 1 and the wire electrode 2 are in a state of being "wrapped" by the electrolyte, providing electrolytic processing conditions, and after wetting the workpiece 1, it is convenient for the micro-droplets to form a micro-liquid flow along the surface of the workpiece 1. The wire electrode 2 performs micro-electrolytic cutting processing on the workpiece 1, and realizes electrolysis in the processing gap area by continuously supplying the micro-liquid flow to the processing gap area. The electrolytic processing method can renew the liquid and remove the products; thereby speeding up the diffusion and migration rate of metal ions on the processing surface, ensuring the complete discharge of insoluble products, enhancing the mass transfer efficiency, speeding up the material removal rate, significantly improving the processing stability, processing quality and processing efficiency, and thus improving the processing conditions; in the electrolytic processing, bubbles are only generated at the processing gap position, and the bubbles generated in the processing gap float upward into the air, avoiding the bubbles from adhering to the surface of the workpiece 1 and the wire electrode 2 to affect the processing accuracy; and the electrolyte has little interference with the wire electrode 2, which can prevent the wire electrode 2 from being deformed due to a large range of disturbances in the electrolyte or a large range of jitters in the wire electrode 2, thereby affecting the processing stability and processing accuracy, and the operation is simple and the operability is strong.

[0019] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A directional droplet flow assisted micro-electrolytic wire cutting processing method, characterized in that: The auxiliary use of this method in micro-electrolytic wire cutting processing is divided into two stages: before the start of processing and during the processing; Before the start of processing: clamp the workpiece and the wire electrode in the electrolyte tank, and connect the workpiece to the positive electrode of the pulse power supply, and connect the wire electrode to the negative electrode of the pulse power supply; use the control system of the CNC machine tool to drive the wire electrode or the workpiece to move, so that the wire electrode and the workpiece are in the processing gap position; turn on the switch of the micro-droplet flow nozzle to spray the electrolyte, adjust the position and angle of the micro-droplet flow nozzle to spray the electrolyte, so that the micro-droplet flow formed by the electrolyte is sprayed on the workpiece to wet its entire surface, and continue to spray the micro-droplet flow to wet the processing gap area with the electrolyte until the micro-droplets form a micro-liquid flow along the surface of the workpiece and flow through the processing area, and the gravity of the micro-droplet flow and the adhesion of the liquid flow make it flow downward along the wire electrode; During the processing: start the pulse power supply, the micro-droplet flow nozzle continuously sprays micro-droplet flow, so that the micro-liquid flow formed by the micro-droplet flow continuously flows to the processing gap, the wire electrode performs micro-electrolytic cutting processing on the workpiece, and the electrolyte in the processing gap area is updated and the product is removed by continuously supplying micro-liquid flow to the processing gap area. The control system of the CNC machine tool drives the wire electrode or the workpiece to move along the cutting path until the processing is completed.

2. A directional droplet flow assisted micro-electrolytic wire cutting processing method according to claim 1, characterized in that: The pulse power supply used in micro-electrolytic wire cutting processing is a nanosecond ultra-short pulse power supply.

3. A directional droplet flow assisted micro-electrolytic wire cutting processing method according to claim 1, characterized in that: A micro-droplet flowmeter and a pressure-boosting device are provided on the liquid inlet pipe connected to the micro-droplet flow nozzle. During the process of the micro-droplet flow nozzle spraying liquid, the spraying flow rate and speed can be adjusted by the micro-droplet flowmeter, and the injection pressure of the micro-droplet flow nozzle can be increased by the pressure-boosting device.

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