阅读说明：本技术 一种激光与电解液复合加工方法及其加工装置 (Laser and electrolyte combined processing method and processing device thereof ) 是由 王玉峰 张文武 于 2019-11-19 设计创作，主要内容包括：本发明公开了一种激光与电解液复合加工方法及其加工装置,属于微细、精密复合加工领域,能够解决现有激光电解复合加工技术对于涂覆绝缘涂层的工件加工过程中存在工艺复杂,加工效率较低的问题。所述方法包括：将工件和管状电极分别与电源的正极和负极连接；将激光束和电解液耦合通过管状电极的中心孔传输至工件的加工区域,以打穿加工区域的绝缘涂层,使得工件和管状电极通过电解液形成导电通路；控制管状电极向加工区域进给,以得到目标结构。本发明用于涂覆绝缘涂层的工件的加工。(The invention discloses a laser and electrolyte composite processing method and a processing device thereof, belongs to the field of micro and precise composite processing, and can solve the problems of complex process and low processing efficiency in the processing process of a workpiece coated with an insulating coating in the existing laser electrolysis composite processing technology. The method comprises the following steps: respectively connecting the workpiece and the tubular electrode with the positive electrode and the negative electrode of a power supply; coupling the laser beam and the electrolyte to transmit to a processing area of the workpiece through a central hole of the tubular electrode so as to punch through an insulating coating of the processing area, and enabling the workpiece and the tubular electrode to form a conductive path through the electrolyte; and controlling the feeding of the tubular electrode to the processing area to obtain the target structure. The invention is used for processing the workpiece coated with the insulating coating.)

1. A laser and electrolyte combined machining method for machining a target structure on a workpiece having an insulating coating, the method comprising:

respectively connecting the workpiece and the tubular electrode with the positive electrode and the negative electrode of a power supply;

transmitting a laser beam and an electrolyte coupled through a central bore of the tubular electrode to a machining region of the workpiece to pierce an insulating coating of the machining region such that the workpiece and the tubular electrode form a conductive path through the electrolyte;

controlling the feeding of the tubular electrode to the machining area to obtain the target structure.

2. The machining method according to claim 1, wherein said controlling the feed of the tubular electrode towards the machining area to obtain the target structure comprises in particular:

controlling the tubular electrode to feed to the machining area and detecting the current in the conductive path;

when the current at the current moment in the conductive path is determined to be smaller than the current at the previous moment, the laser beam is closed;

and controlling the tubular electrode to continuously feed to the processing area, and turning off the power supply when the current in the conductive path is reduced to a first specific value to obtain the target structure.

3. The machining method according to claim 1, wherein said controlling the feed of the tubular electrode towards the machining area to obtain the target structure comprises in particular:

controlling the feeding of the tubular electrode to the machining area, and detecting the electrolyte pressure in the tubular electrode;

closing the laser beam when the pressure of the electrolyte in the tubular electrode at the current moment is determined to be smaller than the pressure of the electrolyte at the previous moment;

and controlling the tubular electrode to continue feeding to the processing area, and turning off the power supply when the electrolyte pressure in the tubular electrode is reduced to a second specific value to obtain the target structure.

4. The processing method according to claim 1,

the tubular electrode comprises an annular conductive layer, an insulating coating arranged on the outer side of the conductive layer and a constraint layer arranged on the inner side of the conductive layer;

the optical refractive index of the constraint layer is smaller than that of the electrolyte;

the electrolyte is transmitted to the processing area through the inner side of the constraint layer;

the laser beam is transmitted to the processing region by total reflection at the confinement layer/electrolyte interface.

5. The process of claim 4, wherein the conductive layer is a metal capillary.

6. The process of claim 4 wherein said constraining layer is made of polytetrafluoroethylene.

7. The laser and electrolyte combined machining device is characterized by comprising a laser module, an electrolysis module and a control module, wherein the control module is connected with the laser module and the electrolysis module;

the electrolysis module comprises a power supply, a tubular electrode and electrolyte; the workpiece and the tubular electrode are respectively connected with the positive electrode and the negative electrode of the power supply;

the electrolyte and the laser beam emitted by the laser module are coupled and transmitted to a processing area of the workpiece through a central hole of the tubular electrode so as to punch through an insulating coating of the processing area, and the workpiece and the tubular electrode form a conductive path through the electrolyte;

the control module is used for controlling the tubular electrode to feed to the processing area so as to obtain the target structure.

8. The processing apparatus as set forth in claim 7 further comprising a current sensor disposed in the conductive path for detecting current in the conductive path;

the control module is specifically configured to:

controlling the tubular electrode to feed to the processing area, and controlling the laser module to be closed when the current at the current moment in the conductive path is determined to be smaller than the current at the previous moment;

controlling the tubular electrode to continue feeding to the machining region and controlling the power supply to be turned off when the current in the conductive path decreases to a first specified value.

9. A machining device as claimed in claim 7, further comprising a pressure sensor disposed in the electrolyte flow path for sensing the electrolyte pressure within the tubular electrode;

the control module is specifically configured to:

controlling the tubular electrode to feed to the processing area, and controlling the laser module to be closed when the pressure of the electrolyte in the tubular electrode at the current moment is determined to be smaller than the pressure of the electrolyte at the previous moment;

controlling the tubular electrode to continue feeding to the machining area, and controlling the power supply to be turned off when the electrolyte pressure in the tubular electrode is reduced to a second specific value.

10. The machining device of claim 7, wherein the control module is further configured to control a motion profile of the tubular electrode and/or the workpiece.

Technical Field

The invention relates to a laser and electrolyte combined machining method and a machining device thereof, belonging to the field of micro and precise combined machining.

Background

In recent years, with the development of advanced manufacturing techniques, new processing techniques have been developed. The laser processing technology uses laser beams as main tools, realizes the removal processing of workpiece materials through the photothermal effect or photochemical effect of light and materials, and has the advantages of high energy density, high resolution, high processing efficiency and the like. The electrochemical machining technology is based on the electrochemical anode dissolution principle to remove workpiece materials, is a non-contact machining mode, and has the advantages of no residual stress and microcrack on the machined surface, no flash and burr and the like. In order to comprehensively utilize the advantages of laser processing and electrolytic processing, a laser electrolytic composite processing technology is provided.

The existing laser electrolysis composite processing technology integrates the advantages of high efficiency of laser processing and good quality of electrolysis processing, can realize high-quality and high-efficiency processing of a micro structure, and a processed workpiece has no remelted layer, no microcrack and good surface integrity.

Disclosure of Invention

The invention provides a laser and electrolyte combined machining method and a machining device thereof, which can solve the problems of complex machining process and low machining efficiency when the existing laser and electrolyte combined machining technology is used for machining a workpiece coated with an insulating coating.

The invention provides a laser and electrolyte combined machining method for machining a target structure on a workpiece with an insulating coating, which comprises the following steps: respectively connecting the workpiece and the tubular electrode with the positive electrode and the negative electrode of a power supply; transmitting a laser beam and an electrolyte coupled through a central bore of the tubular electrode to a machining region of the workpiece to pierce an insulating coating of the machining region such that the workpiece and the tubular electrode form a conductive path through the electrolyte; controlling the feeding of the tubular electrode to the machining area to obtain the target structure.

Optionally, controlling the feeding of the tubular electrode to the processing area to obtain the target structure specifically includes: controlling the tubular electrode to feed to the machining area and detecting the current in the conductive path; when the current at the current moment in the conductive path is determined to be smaller than the current at the previous moment, the laser beam is closed; and controlling the tubular electrode to continuously feed to the processing area, and turning off the power supply when the current in the conductive path is reduced to a first specific value to obtain the target structure.

Optionally, controlling the feeding of the tubular electrode to the processing area to obtain the target structure specifically includes: controlling the feeding of the tubular electrode to the machining area, and detecting the electrolyte pressure in the tubular electrode; closing the laser beam when the pressure of the electrolyte in the tubular electrode at the current moment is determined to be smaller than the pressure of the electrolyte at the previous moment; and controlling the tubular electrode to continue feeding to the processing area, and turning off the power supply when the electrolyte pressure in the tubular electrode is reduced to a second specific value to obtain the target structure.

Optionally, the tubular electrode comprises an annular conductive layer, an insulating coating disposed outside the conductive layer, and a constraining layer disposed inside the conductive layer; the optical refractive index of the constraint layer is smaller than that of the electrolyte; the electrolyte is transmitted to the processing area through the inner side of the constraint layer; the laser beam is transmitted to the processing region by total reflection at the confinement layer/electrolyte interface.

Optionally, the conductive layer is a metal capillary.

Optionally, the constraint layer is made of polytetrafluoroethylene.

The invention also provides a laser and electrolyte combined processing device, which is used for processing a target structure on a workpiece with an insulating coating, and comprises: the electrolytic cell comprises a laser module, an electrolysis module and a control module which is connected with the laser module and the electrolysis module; the electrolysis module comprises a power supply, a tubular electrode and electrolyte; the workpiece and the tubular electrode are respectively connected with the positive electrode and the negative electrode of the power supply; the electrolyte and the laser beam emitted by the laser module are coupled and transmitted to a processing area of the workpiece through a central hole of the tubular electrode so as to punch through an insulating coating of the processing area, and the workpiece and the tubular electrode form a conductive path through the electrolyte; the control module is used for controlling the tubular electrode to feed to the processing area so as to obtain the target structure.

Optionally, the apparatus further comprises a current sensor disposed in the conductive path, the current sensor being configured to detect a current in the conductive path; the control module is specifically configured to: controlling the tubular electrode to feed to the processing area, and controlling the laser module to be closed when the current at the current moment in the conductive path is determined to be smaller than the current at the previous moment; controlling the tubular electrode to continue feeding to the machining region and controlling the power supply to be turned off when the current in the conductive path decreases to a first specified value.

Optionally, the device further comprises a pressure sensor arranged on the electrolyte flow channel, wherein the pressure sensor is used for detecting the electrolyte pressure in the tubular electrode; the control module is specifically configured to: controlling the tubular electrode to feed to the processing area, and controlling the laser module to be closed when the pressure of the electrolyte in the tubular electrode at the current moment is determined to be smaller than the pressure of the electrolyte at the previous moment; controlling the tubular electrode to continue feeding to the machining area, and controlling the power supply to be turned off when the electrolyte pressure in the tubular electrode is reduced to a second specific value.

Optionally, the control module is further configured to control a motion trajectory of the tubular electrode and/or the workpiece.

The invention can produce the beneficial effects that:

1) the invention provides a laser and electrolyte combined processing method, which is characterized in that a workpiece and a tubular electrode are respectively connected with a positive electrode and a negative electrode of a power supply, a laser beam and electrolyte are coupled to pass through a central hole of the tubular electrode to form 'water-conducting laser' and are transmitted to a processing area of the workpiece so as to punch through an insulating coating of the processing area, so that the workpiece and the tubular electrode form a conductive path through the electrolyte, the workpiece is processed by utilizing the water-conducting laser and electrochemical combined technology, the workpiece material can be directly removed by laser processing, the temperature of the processing area can also be increased, the processing efficiency is improved, the electrolyte can etch the processed workpiece, and a heat affected zone and a recasting layer generated by the laser processing can also be synchronously removed, so that a high-quality target structure without a remelted. Compared with the defects that the operation is complex and the processing efficiency is low and the like caused by the fact that the laser and electrolysis combined processing technology needs to be carried out separately in the processing process of a workpiece coated with an insulating coating, the laser and electrolysis combined processing method can realize continuous and staged operation of two processes of laser and electrolysis, and the processing process does not need secondary clamping of the workpiece, replacement of a laser light source, a tool electrode, working solution and the like, so that the operation process is simpler and more convenient, and the processing efficiency is greatly improved.

2) The laser and electrolysis combined machining method provided by the invention is characterized in that in the process of controlling the tubular electrode to feed to a machining area, the current in the conductive passage and the electrolyte pressure in the tubular electrode are detected in real time, when the current or electrolyte pressure value at the current moment is smaller than the last moment value, the laser beam is closed, and when the current is reduced to a first specific value or the electrolyte pressure is reduced to a second specific value, the power supply is closed, so that a machined target structure is obtained. This application comes real-time judgement processing state through the real-time detection to electric current and pressure, can in time adjust work piece motion parameter like this, avoids appearing the short circuit in the processing and processes the back injury scheduling problem, has improved the stability of course of working.

Drawings

FIG. 1 is a flow chart of a laser and electrolyte combined machining method provided in an embodiment of the present invention;

FIG. 2 is a flow chart of another laser and electrolyte combined machining method provided in an embodiment of the present invention;

FIG. 3 is a schematic view of an insulating coating formed by the composite processing of laser and electrolyte provided in an embodiment of the present invention;

FIG. 4 is a schematic diagram of a movement trajectory of a laser coupled jet provided in an embodiment of the present invention;

FIG. 5 is a schematic view of a laser and electrolyte combined machining workpiece provided in an embodiment of the present invention;

FIG. 6 is a schematic diagram illustrating the current variation during the laser and electrolyte combined machining process provided in the embodiment of the present invention;

fig. 7 is a block diagram of a laser and electrolyte combined processing device provided in an embodiment of the present invention.

Detailed Description

The present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.

The embodiment of the invention provides a laser and electrolysis combined machining method, which is used for machining a target structure on a workpiece with an insulating coating, and is shown in figures 1 and 3:

and 101, respectively connecting the workpiece 8 and the tubular electrode 2 with the positive electrode and the negative electrode of the power supply 6.

In practical applications, the workpiece 8 may be a superalloy; the tubular electrode 2 comprises an annular conducting layer 4, an insulating coating 3 arranged on the outer side of the conducting layer and a constraint layer 5 arranged on the inner side of the conducting layer, specifically, the conducting layer 4 can be a metal capillary, and the constraint layer 5 can be made of polytetrafluoroethylene; the positive pole of the power supply 6 is connected to the workpiece 8 and the negative pole of the power supply 6 is connected to the conductive layer 4 of the tubular electrode 2.

Step 102, coupling the laser beam 1 and the electrolyte 10 to transmit to the processing area of the workpiece 8 through the central hole of the tubular electrode 2 to punch through the insulating coating 7 of the processing area, so that the workpiece 8 and the tubular electrode 2 form a conductive path through the electrolyte.

As shown in fig. 3-4, when the laser beam 1 is emitted to the boundary of the constraint layer/electrolyte, the laser beam 1 is totally reflected at the boundary, so that the laser beam 1 is constrained in the range of the constraint layer 5 for conduction, and after the laser beam 1 is emitted from the outlet of the end face of the tube electrode 2, the laser beam 1 continues to form total reflection at the boundary of the electrolyte/air, so as to form a laser coupling jet 11 and act on the region to be processed of the insulating coating 7 of the workpiece. After multiple total reflections, the laser energy of the laser beam 1 is approximately and uniformly distributed in the diameter range of the laser coupling jet flow 11, and the diameter of the laser coupling jet flow 11 is smaller, so that the motion track 13 between the tubular electrode 2 and the workpiece 8 can be digitally controlled by controlling the motion platform 9, and further the processing of the preset contour structure 12 on the workpiece insulating coating 9 is completed. A certain processing gap is preset between the end face of the tubular electrode 2 and the surface of the insulating coating 9, and the insulating coating 7 in the processing area is punched through laser processing, so that the workpiece 8 and the tubular electrode 2 form a conductive path through electrolyte; compare in traditional water guide laser processing technique, tubular electrode 2 in this application can go deep into narrow region, and the water column length shortens in the air, and jet pressure loss is little, is favorable to improving the scouring effect of water jet, in time gets rid of slag, heat etc. that laser beam machining produced, improves the processing surface quality, reduces the surface heat influence.

And 103, controlling the tubular electrode 2 to feed to the processing area to obtain the target structure.

As shown in fig. 5, after the insulating coating 7 is penetrated by the laser, a conductive path is formed among the tubular electrode 2, the electrolyte 10 and the workpiece 8, so as to realize the synchronous coupling of the laser and the electrochemical energy field in the machining gap of the end face of the tubular electrode 2. The laser processing can directly remove workpiece materials and can also increase the temperature of a processing area, thereby improving the electrolytic processing speed. The electrolyte can etch the workpiece 8 and can also synchronously remove a heat affected zone, a recasting layer and the like generated by laser processing, and the surface integrity and the processing precision of the processed small hole are improved, so that a high-quality target structure is obtained. The high-speed flushing of the inner hole of the tubular electrode 2 and the rotary motion of the tubular electrode 2 in the machining process are beneficial to discharging of machining products in the machining gap, and the stability of the machining process is improved.

Compared with the defects that the operation is complex and the processing efficiency is low and the like caused by the fact that the laser and electrolysis combined processing technology needs to be carried out separately in the processing process of a workpiece coated with an insulating coating, the laser and electrolysis combined processing method can realize continuous and staged operation of two processes of laser and electrolysis, and the processing process does not need secondary clamping of the workpiece, replacement of a laser light source, a tool electrode, working solution and the like, so that the operation process is simpler and more convenient, and the processing efficiency is greatly improved.

Another embodiment of the present invention provides a laser and electrolysis combined machining method, as shown in fig. 2, specifically including the following steps:

step 201, connecting the workpiece 8 and the tubular electrode 2 with the positive electrode and the negative electrode of the power supply 6 respectively.

Step 202, coupling the laser beam 1 and the electrolyte 10 to transmit to the processing area of the workpiece 8 through the central hole of the tubular electrode 2 to punch through the insulating coating 7 of the processing area, so that the workpiece 8 and the tubular electrode 2 form a conductive path through the electrolyte.

Step 203, controlling the tubular electrode 2 to feed to the machining area, and detecting the current in the conductive path.

And step 204, when the current at the current moment in the conductive path is determined to be smaller than the current at the previous moment, closing the laser beam.

And step 205, controlling the tubular electrode 2 to continue feeding to the processing area, and turning off the power supply 6 when the current in the conductive path is reduced to a first specific value to obtain the target structure.

In practical application, the tubular electrode 2 is controlled to continuously feed to a machining area, the current change condition in the machining process can be detected and monitored in real time through the current Hall sensor and the high-speed data acquisition system, the machining state is judged in real time through the real-time detection of the current and the pressure, so that the motion parameters of a workpiece can be timely adjusted, the problems of short circuit, machining back damage and the like in machining are avoided, and the stability of the machining process is improved. As shown in fig. 6, when the laser 1 processes the insulating coating 7, the processing current is zero. When at time t ═ t₁At this time, the insulating coating 7 is partially opened, the current starts to be generated, the machining current gradually increases with the increase of the machining time, and the machining current is gradually increased when t is equal to t₂The insulating coating 7 is completely perforated. The tubular electrode 2 is fed into the workpiece 8 along with the feeding, the laser and electrochemical combined machining of the workpiece 8 is started, the machining current is gradually increased along with the increase of the machining depth, and at t₃The current reaches a maximum at that moment and then decreases. At t₃At the moment, the workpiece 8 is partially penetrated, the processing area is reduced, the resistance is increased, the processing current begins to be reduced, the laser 1 is closed at the moment, and the processing damage caused by the fact that the laser 1 penetrates through the workpiece is avoided. And after the laser 1 is closed, controlling the tubular electrode 2 to continue feeding, and through the electrochemical etching processing target structure, when the processing current is reduced to a first specific value, judging that the workpiece 8 is completely penetrated, and closing the power supply 6 at the moment. Under the action of electrochemical etching, the machined structure can be prevented from being formedThe stress concentration problem caused by the existing sharp corner enhances the working reliability of the processing structure.

Optionally, the controlling the feeding of the tubular electrode 2 to the processing area to obtain the target structure further includes:

and 301, controlling the tubular electrode 2 to feed to the processing area, and detecting the pressure of the electrolyte 10 in the tubular electrode 2.

And step 302, when the pressure of the electrolyte 10 in the tubular electrode 2 at the current moment is determined to be smaller than the pressure of the electrolyte 10 at the previous moment, closing the laser beam 1.

And step 303, controlling the tubular electrode 2 to continuously feed to the processing area, and turning off the power supply 6 when the pressure of the electrolyte 10 in the tubular electrode 2 is reduced to a second specific value to obtain the target structure.

In practical application, the pressure sensor is arranged on a flow channel of the electrolyte 10 and used for detecting the pressure change condition of the electrolyte 10 in the machining process, and the machining state is judged in real time through the real-time detection of the pressure, so that the motion parameters of a workpiece can be adjusted in time, the problems of short circuit, machining back damage and the like in the machining process are avoided, and the stability of the machining process is improved. When the workpiece 8 is not punched through in the machining process, the pressure is kept unchanged, and when the workpiece 8 is punched through, the pressure begins to be reduced, and at the moment, the laser beam 1 is closed, so that the machining back injury caused by the fact that the laser beam 1 penetrates through the workpiece 8 is avoided. When the pressure of the electrolyte 10 is reduced to a second specific value, it is judged that the workpiece 8 is completely pierced, and the power supply 6 is turned off. Under the action of electrochemical etching, the stress concentration problem caused by sharp corners of the processing structure can be avoided, and the working reliability of the processing structure is enhanced.

The embodiment of the invention also provides a laser and electrolyte combined machining device, as shown in fig. 7, the machining device comprises a laser module 14, an electrolysis module 15, and a control module 16 connected with both the laser module 14 and the electrolysis module 15, wherein the electrolysis module 15 comprises a power supply 6, a tubular electrode 2, and an electrolyte 10, the workpiece 8 and the tubular electrode 2 are respectively connected with a positive electrode and a negative electrode of the power supply 6, and laser beams emitted by the electrolyte 10 and the laser module 14 are coupled and transmitted to a machining area of the workpiece 8 through a central hole of the tubular electrode 2 to penetrate through an insulating coating 7 of the machining area, so that the workpiece 8 and the tubular electrode 2 form a conductive path through the electrolyte 10. The control module 16 is used to control the feeding of the tubular electrode 2 towards the machining area to obtain the target structure.

Further, the apparatus includes a current sensor disposed in the conductive path for detecting a current in the conductive path. Specifically, the control module 16 controls the tubular electrode 2 to feed to the machining area, and controls the laser module 14 to close when the current in the conductive path at the current moment is determined to be smaller than the current at the previous moment, controls the tubular electrode 2 to continue to feed to the machining area, and controls the power supply 6 to close when the current in the conductive path is reduced to a first specific value.

Optionally, the apparatus further comprises a pressure sensor disposed on the flow path of the electrolyte 10 for detecting the pressure of the electrolyte 10 inside the tubular electrode 2. Specifically, the control module 16 controls the tubular electrode 2 to feed to the machining area, and when it is determined that the pressure of the electrolyte 10 in the tubular electrode 2 at the current moment is lower than the pressure of the electrolyte 10 at the previous moment, the control module controls the laser module 14 to close, controls the tubular electrode 2 to continue to feed to the machining area, and controls the power supply 6 to close when the pressure of the electrolyte 10 in the tubular electrode 2 is reduced to a second specific value.

Optionally, the control module 16 is also used to control the motion trajectory of the tubular electrode 2 and/or the workpiece 8.

The functions and effects of the modules in the device are consistent with those in the method, and are not described herein again.

The above embodiments are described in detail, and although the present invention has been described with reference to preferred embodiments, it should be understood that the present invention is not limited thereto, and various changes and modifications can be made by those skilled in the art without departing from the scope of the present invention.