CN104289775A - Electrolytic cutting method based on composite motion of electrode - Google Patents
Electrolytic cutting method based on composite motion of electrode Download PDFInfo
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- CN104289775A CN104289775A CN201410463370.9A CN201410463370A CN104289775A CN 104289775 A CN104289775 A CN 104289775A CN 201410463370 A CN201410463370 A CN 201410463370A CN 104289775 A CN104289775 A CN 104289775A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23H—WORKING OF METAL BY THE ACTION OF A HIGH CONCENTRATION OF ELECTRIC CURRENT ON A WORKPIECE USING AN ELECTRODE WHICH TAKES THE PLACE OF A TOOL; SUCH WORKING COMBINED WITH OTHER FORMS OF WORKING OF METAL
- B23H3/00—Electrochemical machining, i.e. removing metal by passing current between an electrode and a workpiece in the presence of an electrolyte
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23H—WORKING OF METAL BY THE ACTION OF A HIGH CONCENTRATION OF ELECTRIC CURRENT ON A WORKPIECE USING AN ELECTRODE WHICH TAKES THE PLACE OF A TOOL; SUCH WORKING COMBINED WITH OTHER FORMS OF WORKING OF METAL
- B23H2400/00—Moving mechanisms for tool electrodes
- B23H2400/10—Moving mechanisms for tool electrodes for rotating the electrode
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Abstract
The invention relates to an electrolytic cutting method based on the composite motion of an electrode and belongs to the technical field of electrolytic machining. The method is characterized in that when a tool electrode is used for electrolytic cutting, the tool electrode rotates around the axis of the tool electrode, or the tool electrode carries out reciprocal rectilinear motion in the axis direction, or the rotation around the axis of the tool electrode and the reciprocal rectilinear motion in the axis direction are combined. According to the electrolytic cutting method based on the composite motion of the electrode, discharging of machined products is facilitated by utilizing the composite motion of the electrolytic cutting electrode. The electrolytic cutting method based on the composite motion of the electrode can improve the machining stability, the machining precision and the machining efficiency of a ruled surface structure.
Description
Art
A kind of electrode compound motion electrolysis cutting method of the present invention, belongs to technical field of electrolysis processing.
Background technology
Aero-engine, just towards high-performance, long-life, high reliability direction development, proposes strict demand to part fatigue life, surface integrity.Special requirement aero-engine working-blade tenon, turbine disc mortise, the high cycle fatigue part finished surfaces such as high accuracy travelling gear are without re cast layer, non-microcracked.Mostly this type of part is the ruled surface component that cross sectional shape is complicated, depth-to-width ratio is large, and mostly material is the difficult machining materials such as titanium alloy, high temperature alloy, intermetallic compound.Therefore, great surface quality difficult-to-machine material manufacturing technology has become one of bottleneck of restriction advanced aero engine development.
Tradition machining is thermal force-Li load coupling process, usually produces residual stress at piece surface, forms work hardening layer, reduces the fatigue strength of part.Spark machined, Laser Processing are typical Thermal Load processes, usually form re cast layer and heat affected layer at piece surface; Re cast layer is that melted material cools the quenching cast sturcture of formation fast at piece surface, inner normal containing micro-crack.Under the effect of alternate load, micro-crack is easily expanded, and causes part generation rupture failure.Electrolysis cutting removes material based on electrochemical metal anodic solution principle, and its finished surface is unstressed, without re cast layer, non-microcracked, meet aero-engine difficult-to-machine material great surface quality ruled surface component process requirements especially.
Electrolysis is cut, and adopts line electrode as tool-electrode, can avoid the cathode design of conventional electrolysis formed machining complexity, flow Field Design process, greatly shorten the leading time; Adopt line electrode as tool-electrode, electrolyte is relatively simple on the impact of machining accuracy along journey characteristic, more easily realizes high accuracy processing.Research shows, the essence of high accuracy Electrolyzed Processing is constant microgap processing, and its key is to upgrade electrolyte fast, keeps machining gap electrolyte inside stable conductivity, is evenly distributed.High accuracy electrolysis cutting processing gap at several microns in some tens of pm range scale.In so narrow and small machining gap, exchange of electrolyte, renewal difficulty.
Researcher proposes to adopt coaxial high speed to rush liquid to accelerate electrolyte flow.Along with depth of cut increases, in electrolyte microgap, flow at high speed sharply increases along stroke pressure loss, makes to rush liquid and weakens the disturbance of machining gap deeper inside electrolyte and updating ability.Meanwhile, make up pressure loss effect by raising electrolyte pressure simply also not obvious, also easily bring other negative effects such as electrolyte jet atomization, wire electrode vibration.
Researcher also proposed the auxiliary processes such as the unidirectional wire of line electrode, to-and-fro thread, promotes that elaboration products are discharged by the effect of dragging of wire electrode to electrolyte.Due to line electrode smooth surface, its towing to electrolyte, perturbation action are limited, and during processing high aspect ratio structure, electrolyte upgrades still comparatively slow, and elaboration products and bubble are easily attached to wire electrode and surface of the work, bring out short circuit.
In addition, researcher also proposes the auxiliary process such as workpiece, tool-electrode low-frequency vibration, improves machining gap flow field to a certain extent, solves the problem that elaboration products and bubble are attached to wire electrode and surface of the work.When depth of cut reach tens of even up to a hundred millimeters time, low-frequency vibration effect is very limited.
Therefore, improve the discharge of electrolysate and the renewal speed of electrolyte in electrolysis cutting processing gap, remain the key issue that high aspect ratio structure electrolysis cutting needs to need badly solution.
Summary of the invention
The present invention is directed to existing high aspect ratio structure electrolysis cutting technique elaboration products and discharge a difficult problem, propose a kind of electrode compound motion electrolysis cutting method.By the compound motion of electrolysis cutting electrode, promote the discharge of elaboration products, improve the processing stability of high aspect ratio structure, machining accuracy and working (machining) efficiency.
A kind of electrode compound motion electrolysis cutting method, it is characterized in that comprising following process: utilize electrolysis cutter sweep to carry out electrolysis cutting processing, this device comprises power supply, electrolyte circulation system, electrolysis cutting off machine, electrolysis cutting off machine digital control system, tool cathode system, workpiece system.Step 1, on the numerical control rotating platform of trade union college workpiece system; Step 2, electrolysis cutting electrode is installed on tool cathode system, and electrolysis cutting electrode clamping length and position adjustable, described electrode integral is wire or bar-shaped, and electrode cross-section can for circular or be conducive to the non-circular shape of disturbance electrolyte flow; The complete submergence workpiece of step 3, electrolyte, workpiece connects pulse power positive pole, and electrolysis cutting electrode connects pulse power negative pole, starting impulse power supply; 4, electrolysis in man-hour cutting electrode is added around own axes rotary motion or in axial direction linear reciprocating motion or both compound motions; Step 5, realize the cutting movement of workpiece relative to electrolysis cutting electrode by the interpolation operation of digital control system; Step 6, separation, cleaning workpiece.
Described a kind of electrode compound motion electrolysis cutting method, it is characterized in that: described electrolysis cutting electrode adds man-hour, rotate or linear reciprocating motion or rotate compound linear reciprocating motion in the axial direction around own axes in the axial direction around own axes.
Conventional electrolysis line of cut electrode two ends are often applied in certain pulling force and fix, and realize electrolyte upgrade by the diffusion of electrolyte, convective mass transfer.The technology such as the line electrode occurred in recent years unidirectional wire transporting electrolysis cutting, back and forth wire transporting electrolysis cutting, low-frequency vibration electrode cutting, by tool-electrode low-speed rectilinear movement towing electrolyte in the axial direction, drive electrolysate to discharge in machining gap.To the perturbation action of machining gap electrolyte inside all too " calmness ", mass transfer effect is limited for said method.
This patent proposes electrode and carries out electrolysis cutting with composite motion.Add man-hour, electrolysis cutting electrode rotates with certain speed, simultaneously along electrode axis direction linear reciprocating motion.Electrolysis cutting electrode rotates can increase the agitaion of electrode pair machining gap electrolyte inside, avoids electrolysate to reunite, electrolysate is disperseed, and easilier discharges in machining gap with electrolyte flow.Electrolysis cutting electrode makes axial reciprocating rectilinear motion, makes the electrolyte flow of closing on surface of the work in machining gap not only comprise circumference tangential motion in cross section, also has axial velocity.Now, machining gap electrolyte inside forms strong convection motion, makes to accelerate along cutting thickness direction electrolyte renewal speed.Particularly, when electrolysis cutting electrode carries out Long Distances linear reciprocating motion, this superimposed motion, by directly " dirty " electrolyte containing bubble, electrolysate, Joule heat being taken out of in machining gap, is brought fresh electrolyte in machining gap into.
Simultaneously, the agitaion of electrode compound motion and the channel effect of pulse current, the coupling of pressure wave effect also will be conducive to bubble and surface of the work in electrolyte and collide, make to attach to electrode, the elaboration products of surface of the work come off, enter electrolyte, follow electrolyte flow and discharge in machining gap.
In sum, usefulness of the present invention is: (1) discharge due to product and the renewal quickening of electrolyte, the impurity contents such as machining gap electrolyte inside product, bubble are reduced, avoids because electrolysate piles up the short circuit phenomenon caused, improve processing stability; (2) impurity content such as machining gap electrolyte inside product, bubble reduces, and avoids the sharply reduction along cutting thickness direction electrolytic conductivity, electrolytic conductivity is distributed more even; (3) being uniformly distributed of electrolytic conductivity, improves the carrying current of stable processing, anodic solution speed is accelerated, working (machining) efficiency raising; (4) along with the increase of process velocity, machining gap reduces, and material concentrates ablation ability to strengthen, and improves machining accuracy; (4) effectively improve high aspect ratio structure electrolysis cutting processing gap flow field, under the wide identical condition of seam, can the workpiece cutting more heavy thickness be stablized, improve maximum cutting thickness.
Accompanying drawing explanation
Figure 1 shows that electrode compound motion electrolysis cutting method schematic diagram;
Figure 2 shows that electrolysis cutting electrode compound motion schematic diagram;
Figure 3 shows that electrode compound motion electrolysis cutter sweep schematic diagram;
Number in the figure title: 1, support, 2, electrolytic bath, 3, electrolytic bath seat, 4, electrolyte, 5, X-axis linear electric motors, 6, Y-axis linear electric motors, 7, flowmeter, 8, flow valve, 9, filter, 10, micro pump, 11, liquid reserve tank, 12, heater, 13, thermometer, 14, servo-driver, 15, digital control system, 16, the pulse power, 17, workpiece, 18, numerical control rotating platform, 19, alignment pin, 20, bolt, 21, electro spindle, 22, upper collet, 23, electrolysis cutting electrode, 24, column, 25, upper bracket, 26, XY plane fine-tuning mechanism, 27-1, lower carriage, 27-2, lower adjusting bracket, 28, Z axis linear electric motors, 29, Z-direction micro-adjusting mechanism, 30, balance cylinder.
Detailed description of the invention
Fig. 2 (a) is that electrolysis cutting electrode moves to equilbrium position schematic diagram, Fig. 2 (b) is that electrolysis cutting electrode moves to lower limit position schematic diagram, Fig. 2 (c) is that electrolysis cutting electrode moves to equilbrium position schematic diagram, Fig. 2 (d) is that electrolysis cutting electrode moves to upper extreme position schematic diagram, and Fig. 2 (e) is that electrolysis cutting electrode moves to equilbrium position schematic diagram.
Composition graphs 1, Fig. 2, Fig. 3 illustrate implementation process of the present invention:
1, with reference to figure 3, workpiece 17 is arranged on numerical control rotating platform 18 by alignment pin 19, and fixes with bolt 20;
2, with reference to figure 3, be clamped on the upper collet 22 of electro spindle 21 by electrolysis cutting electrode 23 upper end, lower end is clamped on lower adjusting bracket 27-2.Electrolysis cutting electrode 23 clamping length is adjustable, and regulates the position of electrolysis cutting electrode 23 by Z-direction micro-adjusting mechanism 29 and XY plane fine-tuning mechanism 21;
3, with reference to figure 3, workpiece 17 connects the pulse power 16 positive pole, and electrolysis cutting electrode 23 connects the pulse power 16 negative pole; Start micro pump 10 and adjust flux valve 8, electrolyte 4 injects electrolytic bath 2 until workpiece 17 submergence completely from liquid reserve tank 11;
4, with reference to figure 1,2,3, start digital control system 15, control Z axis linear electric motors 28 and do reciprocating linear motion, realize the linear reciprocating motion of electrolysis cutting electrode 23; Control electro spindle 21, realize the rotary motion of electrolysis cutting electrode 23.Namely electrolysis cutting electrode 23 at vertical direction relative to workpiece 17 from top to bottom, from bottom to top moves to original position again, and the cycle of linear reciprocating motion is T, stroke is A.In electrolysis cutting process, linear reciprocating motion is coupled with the rotary motion around its axis all the time.
5, with reference to figure 3, to digital control system input machined parameters, unbalanced pulse power supply 16, realizes the cutting movement of workpiece 17 relative to electrolysis cutting electrode 23 by the interpolation operation of digital control system, completes the processing of a metal intricate ruled surface structure;
6, separation, cleaning workpiece 17.
Claims (1)
1. an electrode compound motion electrolysis cutting method, is characterized in that comprising following process:
Utilize electrolysis cutter sweep to carry out electrolysis cutting processing, this device comprises power supply, electrolyte circulation system, electrolysis cutting off machine, electrolysis cutting off machine digital control system, tool cathode system, workpiece system;
Step 1, workpiece (17) install workpiece system numerical control rotating platform (18) on;
Step 2, electrolysis cutting electrode (23) is installed on tool cathode system; And electrolysis cutting electrode (23) clamping length and position adjustable; Described electrode integral is wire or bar-shaped, and electrode cross-section can be circle or the non-circular shape being conducive to disturbance electrolyte flow;
Step 3, electrolyte (4) is submergence workpiece (17) completely, and workpiece (17) connects the pulse power (16) positive pole, and electrolysis cutting electrode (23) connects the pulse power (16) negative pole, starting impulse power supply (16);
Step 4, add electrolysis in man-hour cutting electrode (23) and carry out rotary motion around own axes or linear reciprocating motion or both compound motions in the axial direction; Electrode movement can stir machining gap electrolyte inside, avoids electrolysate to reunite, and the electrolysate disperseed easilier is discharged in machining gap with electrolyte flow;
Step 5, realize the cutting movement of workpiece (17) relative to electrolysis cutting electrode (23) by the interpolation operation of digital control system;
Step 6, separation, cleaning workpiece (17).
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106964855A (en) * | 2017-02-15 | 2017-07-21 | 南京航空航天大学 | A kind of asymmetric axial vibration assisted electrolysis wire cutting method of amplitude |
| CN109693009A (en) * | 2019-01-16 | 2019-04-30 | 南京航空航天大学 | Workpiece, which moves back and forth, assists axial fliud flushing electrolysis wire-electrode cutting and processing method and device |
| CN110394516A (en) * | 2019-07-23 | 2019-11-01 | 南京航空航天大学 | High locality pulsation state electrolysis wire-electrode cutting and processing method and device |
| CN110614410A (en) * | 2019-09-20 | 2019-12-27 | 常州工学院 | Horizontal vibration device for dovetail groove electrolytic machining and dovetail groove machining method |
| CN117020342A (en) * | 2023-10-09 | 2023-11-10 | 河南工学院 | Rotary wire electrode auxiliary type electrolytic wire cutting machining device and application method thereof |
Families Citing this family (1)
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| CN108746894B (en) * | 2018-05-24 | 2020-01-21 | 南京航空航天大学 | Micro-tube electrode pulse dynamic electrolytic cutting method |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106964855A (en) * | 2017-02-15 | 2017-07-21 | 南京航空航天大学 | A kind of asymmetric axial vibration assisted electrolysis wire cutting method of amplitude |
| CN109693009A (en) * | 2019-01-16 | 2019-04-30 | 南京航空航天大学 | Workpiece, which moves back and forth, assists axial fliud flushing electrolysis wire-electrode cutting and processing method and device |
| CN110394516A (en) * | 2019-07-23 | 2019-11-01 | 南京航空航天大学 | High locality pulsation state electrolysis wire-electrode cutting and processing method and device |
| CN110614410A (en) * | 2019-09-20 | 2019-12-27 | 常州工学院 | Horizontal vibration device for dovetail groove electrolytic machining and dovetail groove machining method |
| CN110614410B (en) * | 2019-09-20 | 2020-09-01 | 常州工学院 | Horizontal vibration device for dovetail groove electrolytic machining and dovetail groove machining method |
| CN117020342A (en) * | 2023-10-09 | 2023-11-10 | 河南工学院 | Rotary wire electrode auxiliary type electrolytic wire cutting machining device and application method thereof |
| CN117020342B (en) * | 2023-10-09 | 2024-01-26 | 河南工学院 | Rotary wire electrode auxiliary type electrolytic wire cutting machining device and application method thereof |
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