A Precision Control Method and System for Electrochemical Wire Cutting Finishing of Complex Profiles

Abstract

The present application discloses a precision control method and system for electrolytic wire cutting and finishing of complex profiles, which relates to the technical field of electrolytic machining. The method includes decomposing the cross-sectional profile of the electrolytic wire to be cut and finished into straight line segments, convex circular arc segments and concave circular arc segments based on geometry; according to Faraday's law, respectively determining the mathematical relationships between the material removal depth and each processing parameter during electrolytic wire cutting and finishing at each segment; substituting the obtained circular arc curvature radius, wire electrode radius, average current density value collected according to test records or calculated by electric field simulation, and wire electrode sweeping speed into the mathematical relationships, and taking the wire electrode sweeping speed of the straight line segment as the standard, respectively calculating the wire electrode sweeping speeds of the concave circular arc segment and the convex circular arc segment; according to the calculated wire electrode sweeping speeds of the concave circular arc segment, the convex circular arc segment and the straight line segment, performing electrolytic wire cutting and finishing. The present application can improve the machining profile accuracy of parts.

Description

Technical Field

[0001] The present application relates to the technical field of electrolytic machining, and in particular to a method and system for controlling the precision of electrolytic wire cutting and finishing of complex profiles. Background Art

[0002] Special machining is an important supplement to the machining of tenon grooves, mainly including electric discharge wire cutting and electrolytic wire cutting methods. Both electric discharge wire cutting and electrolytic wire cutting use metal wires for machining, without the need for specially made cathode tools, greatly reducing the tool cost. The advantage of electric discharge wire cutting lies in high efficiency, but there is a recast layer on the machined surface and the fatigue life is low. The advantage of electrolytic wire cutting is that the cathode tool has no loss, and there is no recast layer and residual stress on the machined surface. The machining mode of electric discharge wire cutting rough machining + electrolytic wire cutting finishing can realize the low-cost and high-efficiency machining of turbine disk tenon grooves. The rough profile of the tenon groove is pre-cut using the high efficiency advantage of electric discharge wire cutting, and then the profile surface is finished using the good surface quality advantage of electrolytic wire cutting to meet the surface quality requirements of tenon groove machining.

[0003] However, the control of the machining precision of electrolytic wire cutting finishing is a difficult problem. There is a machining gap between the anode and cathode of electrolytic wire cutting. The wire electrode and the anode workpiece are conducted through a neutral salt solution. Under the action of the electric field, the anode material in the gap undergoes electrochemical dissolution. According to Faraday's law, the removal amount of the anode material is proportional to the electric quantity. The full profile of the turbine disk tenon groove can be geometrically decomposed into straight line segments and circular arc segments. In the electrolytic wire cutting and finishing of the turbine disk tenon groove, when the wire electrode sweeps through the above different positions at a constant speed, the integral electric quantity distribution on the workpiece surface is different, manifested as a large difference in the material removal depth of circular arc segments with different curvature radii and the material removal depth of straight line segments, thus having a negative impact on the profile precision of the machined workpiece. In order to meet the manufacturing requirements that the full profile precision of the turbine disk tenon groove reaches the set standard, it is urgent to propose a method for controlling the precision of electrolytic wire cutting of complex profiles to ensure the same material removal depth during the finishing of the turbine disk tenon groove and achieve high-precision machining. Summary of the Invention

[0004] The purpose of the present application is to provide a method and system for controlling the precision of electrolytic wire cutting and finishing of complex profiles, which can solve the problem of uncontrollable precision during the electrolytic wire cutting and finishing of existing complex profiles and improve the machining profile precision of parts.

[0005] To achieve the above purpose, the present application provides the following solutions:

[0006] In the first aspect, the present application provides a method for controlling the precision of electrolytic wire cutting and finishing of complex profiles, including:

[0007] Obtain the cross-sectional profile of the electrolytic wire to be cut and finished.

[0008] Decompose the cross-sectional profile into straight line segments, convex circular arc segments, and concave circular arc segments based on geometry.

[0009] According to Faraday's law, respectively determine the mathematical relationships between the material removal depth and each processing parameter during electrolytic wire cutting and finishing at the concave circular arc segment, the convex circular arc segment, and the straight line segment; the processing parameters include the circular arc curvature radius, the wire electrode radius, the average current density value, and the wire electrode sweeping speed.

[0010] Substitute the obtained circular arc curvature radius, wire electrode radius, average current density value collected according to the test records or calculated by electric field simulation, and wire electrode sweeping speed into the mathematical relationships, and respectively calculate the wire electrode sweeping speeds of the concave circular arc segment and the convex circular arc segment with the wire electrode sweeping speed of the straight line segment as the standard; the wire electrode sweeping speed of the concave circular arc segment is the wire electrode sweeping speed that makes the material removal depth of the concave circular arc segment equal to the material removal depth of the straight line segment; the wire electrode sweeping speed of the convex circular arc segment is the wire electrode sweeping speed that makes the material removal depth of the convex circular arc segment equal to the material removal depth of the straight line segment.

[0011] According to the calculated wire electrode sweeping speeds of the concave circular arc segment, the convex circular arc segment, and the straight line segment, use a tool wire electrode to perform electrolytic wire cutting and finishing on the electrolytic wire to be cut and finished.

[0012] In a second aspect, the present application provides a complex profile electrolytic wire cutting and finishing accuracy control system, including:

[0013] A parameter acquisition module for acquiring the cross-sectional profile of the electrolytic wire to be cut and finished.

[0014] A decomposition module for decomposing the cross-sectional profile into straight line segments, convex circular arc segments, and concave circular arc segments based on geometry.

[0015] A first calculation module for respectively determining the mathematical relationships between the material removal depth and each processing parameter during electrolytic wire cutting and finishing at the concave circular arc segment, the convex circular arc segment, and the straight line segment according to Faraday's law; the processing parameters include the circular arc curvature radius, the wire electrode radius, the average current density value, and the wire electrode sweeping speed.

[0016] A second calculation module, configured to substitute the obtained arc curvature radius, wire electrode radius, average current density value collected according to test records or calculated by electric field simulation, and wire electrode sweeping speed into a mathematical relationship formula, and calculate the wire electrode sweeping speeds of the concave arc segment and the convex arc segment respectively with the wire electrode sweeping speed of the straight segment as a standard; the wire electrode sweeping speed of the concave arc segment is the wire electrode sweeping speed that makes the material removal depth of the concave arc segment equal to the material removal depth of the straight segment; the wire electrode sweeping speed of the convex arc segment is the wire electrode sweeping speed that makes the material removal depth of the convex arc segment equal to the material removal depth of the straight segment.

[0017] A machining module, configured to perform electrolytic wire cutting and finishing machining on the to-be-cut and finished electrolytic wire by using a tool wire electrode according to the calculated wire electrode sweeping speeds of the concave arc segment, the convex arc segment, and the straight segment.

[0018] According to the specific embodiments provided by the present application, the following technical effects are disclosed in the present application:

[0019] The present application provides a method and a system for controlling the machining accuracy of electrolytic wire cutting and finishing of complex profiles. By decomposing the cross-sectional profile of the to-be-cut and finished electrolytic wire obtained into a straight segment, a convex arc segment, and a concave arc segment, each segment can be controlled specifically. According to Faraday's law, the mathematical relationships between the material removal depth and each machining parameter are determined respectively when performing electrolytic wire cutting and finishing machining at the concave arc segment, the convex arc segment, and the straight segment. Then, the obtained arc curvature radius, wire electrode radius, average current density value collected according to test records or calculated by electric field simulation, and wire electrode sweeping speed are substituted into the mathematical relationship formula, and the wire electrode sweeping speeds of the concave arc segment and the convex arc segment are calculated respectively with the wire electrode sweeping speed of the straight segment as a standard; after calculating the speeds of each segment, when machining the to-be-cut and finished electrolytic wire, different wire electrode sweeping speeds can be used to machine different segments, ensuring that the integrated electric quantity at each characteristic position during the electrolytic wire cutting and finishing machining of complex profile parts is equal, and making the material removal depth of the entire profile of the part consistent. Description of the Drawings

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0021] Figure 1 It is a schematic flowchart of a method for controlling the machining accuracy of electrolytic wire cutting and finishing of complex profiles provided by an embodiment of the present application.

[0022] Figure 2 It is an example model diagram of the anode workpiece in a precision control method for electrolytic wire cutting and finishing of complex profiles provided by an embodiment of the present application.

[0023] Figure 3 It is a schematic diagram of the geometric models of straight line segments and circular arc segments in a precision control method for electrolytic wire cutting and finishing of complex profiles provided by an embodiment of the present application.

[0024] Figure 4 It is a simulation diagram of the material removal profile when the precision control method for electrolytic wire cutting and finishing of complex profiles is used and not used during electrolytic wire cutting and finishing provided by an embodiment of the present application.

[0025] Figure 5 It is a schematic diagram of electrolytic wire cutting and finishing in a precision control method for electrolytic wire cutting and finishing of complex profiles provided by an embodiment of the present application.

[0026] Figure 6 It is a test result diagram of the profile error when the precision control method for electrolytic wire cutting and finishing of complex profiles is used and not used during electrolytic wire cutting and finishing provided by an embodiment of the present application.

[0027] Figure 7 It is a structural diagram of a precision control system for electrolytic wire cutting and finishing of complex profiles provided by an embodiment of the present application.

[0028] Symbol description: convex arc segment - 1, straight line segment - 2, concave arc segment - 3, rotating motor - 4, wire electrode - 5, workpiece - 6, guide - 7, DC power supply - 8, electrolyte domain - 9. Detailed implementation manners

[0029] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0030] To make the above - mentioned objects, features, and advantages of the present application more obvious and understandable, the present application will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0031] Embodiment 1

[0032] As Figure 1 shown, this embodiment provides a precision control method for electrolytic wire cutting and finishing of complex profiles, including:

[0033] Step 101: Obtain the cross-sectional profile of the electrolytic wire to be cut and finish-machined.

[0034] Step 102: Decompose the cross-sectional profile into straight line segments 2, convex circular arc segments 1, and concave circular arc segments 3 based on geometry.

[0035] Step 103: According to Faraday's law, respectively determine the mathematical relationships between the material removal depth and various machining parameters during the electrolytic wire cutting and finish-machining of the concave circular arc segment 3, the convex circular arc segment 1, and the straight line segment 2; the machining parameters include the circular arc curvature radius, the wire electrode radius, the average current density value, and the wire electrode sweeping speed.

[0036] Step 104: Substitute the obtained circular arc curvature radius, wire electrode radius, average current density value collected according to test records or calculated by electric field simulation, and wire electrode sweeping speed into the mathematical relationships, and respectively calculate the wire electrode sweeping speeds of the concave circular arc segment 3 and the convex circular arc segment 1 with the wire electrode sweeping speed of the straight line segment 2 as the standard; the wire electrode sweeping speed of the concave circular arc segment 3 is the wire electrode sweeping speed that makes the material removal depth of the concave circular arc segment 3 equal to the material removal depth of the straight line segment 2; the wire electrode sweeping speed of the convex circular arc segment 1 is the wire electrode sweeping speed that makes the material removal depth of the convex circular arc segment 1 equal to the material removal depth of the straight line segment 2.

[0037] Step 105: According to the calculated wire electrode sweeping speeds of the concave circular arc segment 3, the convex circular arc segment 1, and the straight line segment 2, use a tool wire electrode to perform electrolytic wire cutting and finish-machining on the electrolytic wire to be cut and finish-machined.

[0038] Among them, in some embodiments, when performing Step 101, specifically, it can be as follows:

[0039] The electrolytic wire to be cut and finish-machined is the electrolytic wire obtained after rough machining by wire electrical discharge machining, that is, the wire obtained by rough machining by wire electrical discharge machining is set as the electrolytic wire to be cut and finish-machined.

[0040] Among them, in some embodiments, when performing Steps 102 - 103, specifically, it can be as follows:

[0041] As Figure 2 shown, taking the fir-tree type tenon groove of the engine turbine disk as an example, the complex contour to be machined of the workpiece 6 can be decomposed into: convex circular arc segment 1, straight line segment 2, concave circular arc segment 3.

[0042] As Figure 3 shown in the geometric model diagram of the straight line segment 2 and the circular arc segment in the complex contour electrolytic wire cutting and finish-machining accuracy control method, Figure 3(a) Geometric model diagram of straight line segment 2, (b) geometric model diagram of convex arc segment 1, and (c) geometric model diagram of concave arc segment 3. According to the geometric model diagrams, study the relationship between the material removal depth of straight line segment 2, convex arc segment 1, and concave arc segment 3 and the wire electrode sweeping speed in electrolytic wire cutting finishing. Through mathematical derivation, calculate the material removal depth per unit arc length. According to Faraday's law, the material removal volumes V of the straight line, convex arc, and concave arc are respectively:

[0043]

[0044] Among them, ω is the electrochemical volume equivalent, τ is the unit vector along the trajectory direction, H is the part thickness, ī is the average current density, t is the processing time, α and R are the fillet and arc radius respectively, and r is the wire electrode radius. The subscript sl represents the straight line, cc represents the concave arc, and cx represents the convex arc.

[0045] According to the geometric shape calculation, the material removal volumes V of the straight line, convex arc, and concave arc are also equal to:

[0046]

[0047] From Equation (1) and Equation (2), the material removal depths of the straight line segment, convex arc segment, and concave arc segment are respectively:

[0048]

[0049] It can be seen from Equation (3) that the material removal depth Δe is proportional to the average current density ī, positively correlated with the processing arc radius R, and inversely proportional to the wire electrode sweeping speed v f In addition, the material removal depth Δe of the convex arc cx is positively correlated with the wire electrode radius r, and the material removal depth Δe of the concave arc cc is negatively correlated with the wire electrode radius r. When performing step 104, taking the wire electrode sweeping speed of the straight line segment 2 as the criterion, in order to achieve uniform material removal, the wire electrode sweeping speeds of the convex arc and concave arc should be set as:

[0050]

[0051] Among them, Δe sl is the material removal depth of the straight line segment 2, Δe cx is the material removal depth of the convex arc segment 1, Δe cc is the material removal depth of the concave arc segment 3, ω is the electrochemical volume equivalent, α and R are the fillet and arc radii respectively, is the average current density of the straight line segment 2, is the average current density of the convex arc segment 1, is the average current density of the concave arc segment 3, r is the radius of the wire electrode, is the sweeping speed of the wire electrode in the straight segment 2, is the sweeping speed of the wire electrode in the convex arc segment 1, is the sweeping speed of the wire electrode in the concave arc segment 3.

[0052] Among them, when performing step 105, it may specifically include:

[0053] The calculated sweeping speeds of the wire electrode in the concave arc segment 3, the sweeping speed of the wire electrode in the convex arc segment 1, and the sweeping speed of the wire electrode in the straight segment 2 are incorporated into the G-code instructions of the complex contour machining trajectory to obtain a machining program programmed using the machining accuracy control method.

[0054] The workpiece 6 is connected to the positive pole of the DC power supply 8, the tool wire electrode (a metal wire with a diameter of 0.5 - 1 mm) is connected to the negative pole of the DC power supply 8. At the same time, the wire electrode 5 rotates around its axis at a preset speed (1000 - 10000 rpm). The workpiece 6 and the tool electrode are immersed in the electrolyte. The machining program programmed using the machining accuracy control method is imported. The power supply is turned on, and the wire electrode 5 sweeps along the complex part contour according to the preset trajectory and the preset regulation speed for electrolytic wire cutting finishing machining. After machining, the material removal depths of its different characteristic contour segments are measured.

[0055] Specifically, as Figure 4 shown, (a) is the simulation diagram of the material removal contour using the complex contour electrolytic wire cutting finishing machining accuracy control method during electrolytic wire cutting finishing machining, and (b) is the simulation diagram of the material removal contour without using the complex contour electrolytic wire cutting finishing machining accuracy control method during electrolytic wire cutting finishing machining. The simulation parameters of the case are shown in Table 1. When the electrolytic wire cutting finishing machining does not perform dynamic speed regulation, the charge distributions of the convex arc segment 1, the straight segment 2, and the concave arc segment 3 are different, resulting in unequal material removal depths. When the electrolytic wire cutting finishing machining performs dynamic speed regulation, the charge distributions of the convex arc segment 1, the straight segment 2, and the concave arc segment 3 are equal, and the material removal depths are equal.

[0056] Table 1 Simulation parameters

[0057] Parameter Value Radius of wire electrode (r) 0.5 mm Radius of convex and concave arcs on the workpiece (R) 0.8 mm Voltage (U) 14V Actual electro - chemical volume equivalent (ηω) 2.050 [mm3 / (A·min) Sweeping speed of wire electrode (vf) 3 mm / min Electrolyte conductivity (σ0) (0.33 mS / cm)

[0058] The specific machining schematic diagram, as Figure 5 shown, includes: a rotating motor 4, a wire electrode 5, a workpiece 6, a guide 7, a DC power supply 8, and an electrolyte domain 9; the wire electrode 5 is installed on the rotating motor 4 through the guide 7; the wire electrode 5 is connected to the negative pole of the DC power supply 8, and the workpiece 6 is connected to the positive pole of the DC power supply 8; the workpiece 6 and the wire electrode 5 are immersed in the electrolyte domain 9; the power supply is turned on, and the wire electrode 5 feeds along the contour of the workpiece 6 according to the preset motion trajectory and sweeping speed for machining.

[0059] The contour error test result diagrams of electrolytic wire cutting finishing with and without the complex contour electrolytic wire cutting finishing accuracy control method are shown in Figure 6 (a) and (b) of it. (a) is the contour error test result diagram without the complex contour electrolytic wire cutting finishing accuracy control method. It can be seen that compared with the contour error test result diagram of (b) with the complex contour electrolytic wire cutting finishing accuracy control method, the contour error after adopting this method is significantly smaller. The test parameters of the case are shown in Table 2. The contour error of the complex part contour after electrolytic wire cutting finishing is measured. When dynamic speed regulation is not carried out during electrolytic wire cutting finishing, the contour errors of convex arc segment 1 and concave arc segment 3 are significantly higher than those of straight segment 2, and the overall contour error is ±50 μm. When dynamic speed regulation is carried out during electrolytic wire cutting finishing, the contour errors of convex arc segment 1 and concave arc segment 3 are significantly reduced, and the overall contour error is ±18 μm.

[0060] Table 2 Test Parameters

[0061]

[0062]

[0063] Example Two

[0064] As shown in Figure 7 , this example provides a complex contour electrolytic wire cutting finishing accuracy control system, including:

[0065] A parameter acquisition module 701, configured to acquire the cross-sectional contour of the electrolytic wire to be cut and finished.

[0066] A decomposition module 702, configured to decompose the cross-sectional contour into a straight segment 2, a convex arc segment 1, and a concave arc segment 3 based on geometry.

[0067] A first calculation module 703, configured to respectively determine, according to Faraday's law, the mathematical relationships between the material removal depth and each processing parameter when electrolytic wire cutting finishing is carried out at the concave arc segment 3, the convex arc segment 1, and the straight segment 2; the processing parameters include the arc curvature radius, the wire electrode radius, the average current density value, and the wire electrode sweeping speed.

[0068] The second calculation module 704 is configured to substitute the obtained arc curvature radius, wire electrode radius, average current density value collected according to test records or calculated by electric field simulation, and wire electrode sweeping speed into a mathematical relationship formula, and calculate the wire electrode sweeping speeds of the concave arc segment 3 and the convex arc segment 1 respectively with the wire electrode sweeping speed of the straight segment 2 as a standard; the wire electrode sweeping speed of the concave arc segment 3 is the wire electrode sweeping speed that makes the material removal depth of the concave arc segment 3 equal to the material removal depth of the straight segment 2; the wire electrode sweeping speed of the convex arc segment 1 is the wire electrode sweeping speed that makes the material removal depth of the convex arc segment 1 equal to the material removal depth of the straight segment 2.

[0069] The machining module 705 is configured to perform electrolytic wire cutting and finishing on the wire to be cut and finished by using a tool wire electrode according to the calculated wire electrode sweeping speeds of the concave arc segment 3, the convex arc segment 1, and the straight segment 2.

[0070] Wherein, the machining module 705 includes:

[0071] A program programming sub-module, configured to incorporate the calculated wire electrode sweeping speeds of the concave arc segment 3, the convex arc segment 1, and the straight segment 2 into the G-code instructions of the complex contour machining trajectory to obtain a machining program programmed by using a machining accuracy control method.

[0072] A machining sub-module, configured to perform electrolytic wire cutting and finishing by sweeping the energized tool wire electrode along the complex part contour according to a preset trajectory and a preset regulation speed based on the machining program programmed by using a machining accuracy control method.

[0073] In summary, the present application has the following technical effects:

[0074] The present application dynamically adjusts the sweeping speed of the wire electrode 5 to ensure that during the machining process, the average current density at each characteristic position is consistent whether it is the straight segment 2, the convex arc segment 1, or the concave arc segment 3, so as to ensure uniform material removal depth of the overall contour of the part and achieve high-precision contour machining.

[0075] The method in the present application uses a mathematical formula related to the arc curvature radius, wire electrode radius, and average current density to accurately calculate the wire electrode sweeping speeds required for different characteristic positions, and seamlessly integrates them into the machine tool system through numerical control programming to achieve on-line dynamic adjustment during the machining process without interrupting the operation, greatly improving the machining efficiency and accuracy.

[0076] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0077] Specific examples are used in this article to elaborate on the principles and implementation manners of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those of ordinary skill in the art, according to the idea of the present application, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A method for controlling the precision of electrolytic wire cutting finishing of complex contours, characterized in that: include: Obtaining a cross-sectional profile of the electrolytic wire to be cut and finished; Decomposing the cross-sectional profile into straight line segments, convex arc segments and concave arc segments based on geometry; According to Faraday's law, mathematical relationships between material removal depth and various processing parameters are determined when electrolytic wire cutting finishing processing is performed at the concave arc segment, the convex arc segment and the straight line segment; the processing parameters include arc curvature radius, wire electrode radius, average current density value and wire electrode sweeping speed; Substitute the acquired arc curvature radius, wire electrode radius, average current density value collected according to test records or calculated by electric field simulation, and wire electrode sweeping speed into the mathematical formula, and take the wire electrode sweeping speed of the straight line segment as the standard to respectively calculate the wire electrode sweeping speed of the concave arc segment and the wire electrode sweeping speed of the convex arc segment; the wire electrode sweeping speed of the concave arc segment is the wire electrode sweeping speed that makes the material removal depth of the concave arc segment equal to that of the straight line segment; the wire electrode sweeping speed of the convex arc segment is the wire electrode sweeping speed that makes the material removal depth of the convex arc segment equal to that of the straight line segment; According to the calculated wire electrode sweeping speed of the concave arc segment, the wire electrode sweeping speed of the convex arc segment and the wire electrode sweeping speed of the straight line segment, the tool wire electrode is used to perform electrolytic wire cutting finishing processing on the electrolytic wire to be cut and finished.

2. A complex contour electrolytic wire cutting finishing machining accuracy control method according to claim 1, characterized in that: The electrolytic wire to be cut and finished is the electrolytic wire obtained after rough machining by electric spark wire cutting.

3. A complex contour electrolytic wire cutting finishing machining accuracy control method according to claim 1, characterized in that: The mathematical relationship between the material removal depth and various processing parameters when the electrolytic wire cutting finishing process is performed on the concave arc segment, the convex arc segment and the straight line segment is specifically: Among them, Δe sl is the material removal depth of the straight segment, Δe cx is the material removal depth of the convex arc segment, Δe cc is the material removal depth of the concave arc segment, ω is the electrochemical volume equivalent, α and R are the radius of the fillet and the arc, respectively. is the average current density of the straight line segment, is the average current density of the convex arc segment, is the average current density of the concave arc segment, r is the radius of the wire electrode, is the wire electrode sweeping speed of the straight line segment, is the wire electrode sweeping speed of the convex arc segment, is the wire electrode sweeping speed of the concave arc segment.

4. A complex contour electrolytic wire cutting finishing machining accuracy control method according to claim 1, characterized in that: Substitute the obtained arc curvature radius, wire electrode radius, average current density value collected according to test records or calculated by electric field simulation, and wire electrode sweeping speed into the mathematical formula, and take the wire electrode sweeping speed of the straight line segment as the standard to calculate the wire electrode sweeping speed of the concave arc segment and the wire electrode sweeping speed of the convex arc segment, specifically including: According to the formula Calculate the wire electrode sweeping speed of the convex arc segment; Where R is the radius of the arc, is the average current density of the straight line segment, is the average current density of the convex arc segment, r is the radius of the wire electrode, is the wire electrode sweeping speed of the straight line segment, is the wire electrode sweeping speed of the convex arc segment.

5. The method for controlling the precision of electrolytic wire cutting finishing of complex contours according to claim 1, characterized in that: Substitute the obtained arc curvature radius, wire electrode radius, average current density value collected according to test records or calculated by electric field simulation, and wire electrode sweeping speed into the mathematical formula, and take the wire electrode sweeping speed of the straight line segment as the standard to calculate the wire electrode sweeping speed of the concave arc segment and the wire electrode sweeping speed of the convex arc segment, specifically including: According to the formula Calculate the wire electrode sweeping speed of the concave arc segment; Where R is the radius of the arc, is the average current density of the straight line segment, is the average current density of the concave arc segment, r is the radius of the wire electrode, is the wire electrode sweeping speed of the straight line segment, is the wire electrode sweeping speed of the concave arc segment.

6. A complex contour electrolytic wire cutting finishing machining accuracy control method according to claim 1, characterized in that: According to the calculated wire electrode sweeping speed of the concave arc segment, the wire electrode sweeping speed of the convex arc segment and the wire electrode sweeping speed of the straight line segment, the electrolytic wire to be cut and finished is subjected to electrolytic wire cutting and finishing processing, specifically including: The calculated wire electrode sweeping speed of the concave arc segment, the wire electrode sweeping speed of the convex arc segment and the wire electrode sweeping speed of the straight line segment are programmed into the G code instruction of the complex contour machining trajectory to obtain a machining program programmed by a machining precision control method; Based on the machining program programmed using the machining precision control method, the energized tool wire electrode is swept along the contour of the complex part at a preset trajectory and a preset control speed to perform electrolytic wire cutting finishing processing.

7. A method for controlling the precision of complex contour electrolytic wire cutting finishing according to claim 6, characterized in that: The tool wire electrode rotates around its axis at a preset speed; the preset speed range is 1000-10000 rpm.

8. A method for controlling the precision of electrolytic wire cutting finishing of complex contours according to claim 7, characterized in that: The tool wire electrode is a metal wire with a diameter of 0.5-1 mm.

9. A complex contour electrolytic wire cutting finishing precision control system, characterized in that: include: A parameter acquisition module, used to obtain the cross-sectional profile of the electrolytic wire to be cut and finished; A decomposition module, for decomposing the cross-sectional profile into straight line segments, convex arc segments and concave arc segments based on geometry; The first calculation module is used to determine, according to Faraday's law, a mathematical relationship between a material removal depth and various processing parameters when performing electrolytic wire cutting finishing processing at the concave arc segment, the convex arc segment and the straight line segment; the processing parameters include an arc curvature radius, a wire electrode radius, an average current density value and a wire electrode sweeping speed; The second calculation module is used to substitute the acquired arc curvature radius, wire electrode radius, average current density value collected according to the test record or calculated by electric field simulation, and wire electrode sweeping speed into the mathematical relationship, and take the wire electrode sweeping speed of the straight line segment as the standard to respectively calculate the wire electrode sweeping speed of the concave arc segment and the wire electrode sweeping speed of the convex arc segment; the wire electrode sweeping speed of the concave arc segment is the wire electrode sweeping speed that makes the material removal depth of the concave arc segment equal to the material removal depth of the straight line segment; the wire electrode sweeping speed of the convex arc segment is the wire electrode sweeping speed that makes the material removal depth of the convex arc segment equal to the material removal depth of the straight line segment; The processing module is used to perform electrolytic wire cutting finishing processing on the electrolytic wire to be cut and finished using a tool wire electrode according to the calculated wire electrode sweeping speed of the concave arc segment, the wire electrode sweeping speed of the convex arc segment and the wire electrode sweeping speed of the straight line segment.

10. A complex contour electrolytic wire cutting finishing precision control system according to claim 9, characterized in that: The processing module comprises: A program programming submodule is used to program the calculated wire electrode sweeping speed of the concave arc segment, the wire electrode sweeping speed of the convex arc segment and the wire electrode sweeping speed of the straight line segment into the G code instruction of the complex contour machining trajectory to obtain a machining program programmed by a machining precision control method; The processing submodule is used to sweep the energized tool wire electrode along the contour of a complex part at a preset trajectory and a preset control speed based on a processing program programmed using a processing precision control method to perform electrolytic wire cutting finishing processing.

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