Composite processing method for controllable discharge induced grinding of conductive ceramic matrix composite material

Abstract

The invention provides a composite machining method for controllable discharge induced grinding of a conductive ceramic-based composite material, and belongs to the field of electric spark grinding composite machining.According to the composite machining method, surface modification of the ceramic-based composite material is induced through controllable pulse energy, and a loose layer structure which is controllable in thickness and rich in microcracks and air holes is generated; and the difficulty of grinding machining is greatly reduced, tool abrasion is reduced, then crack expansion is restrained, and low-damage machining is achieved. The abrasive particle areas and the discharge areas on the tool electrode are distributed in a staggered mode, the discharge induction and the grinding removal amount of materials can be actively adjusted and controlled, discharge corrosion removal and grinding removal are synchronously carried out, discharge and grinding integrated machining is achieved, and the machining efficiency is improved. The orderly distributed abrasive particles can play a role in strengthening mass transfer and promoting chip removal, and the discharge stability can be improved.

Description

Technical Field

[0001] The present invention relates to the field of electrical discharge grinding composite machining, and specifically refers to a composite machining method for controllable discharge-induced grinding of conductive ceramic matrix composites. Background Art

[0002] With the rapid development of cutting-edge technologies such as hypersonic aircraft, aero-engines, space cameras, and braking systems, the demand for materials with low density and stable high-temperature mechanical properties in thermal protection systems and components is increasing day by day. Carbon fiber or silicon carbide fiber-reinforced tough ceramic matrix composites are of great significance for the strategic upgrade of high-end equipment. However, such materials have the characteristics of high hardness, great brittleness, and anisotropy, making it difficult to manufacture them efficiently with low damage. Moreover, the fiber braiding characteristics of such materials make it difficult to trim the damaged layer through secondary finishing.

[0003] The currently typical machining method for ceramic matrix composites is grinding. The high-hardness ceramic matrix is extremely likely to cause severe wear of the cutting tool, resulting in high tool usage costs and low machining efficiency. The hard-on-hard contact machining is extremely likely to cause the ceramic matrix to break. Since the morphology of the carbon fiber or silicon carbide fiber reinforcement phase depends on the braiding process and the fiber orientation is relatively complex, grinding is extremely likely to cause damage forms such as macroscopic brittle fracture of the fiber and interfacial debonding. Currently, the research focus is on introducing laser energy field-assisted grinding machining. However, the thermal affected zone is relatively large under the "thermal accumulation" effect, and the thickness is usually greater than 100 μm. The coupling of laser-induced ablation and grinding machining is strong, and the process integration is difficult. Restricted by the characteristics of deep and narrow grooves on the complex surface of thermal protection system components, the consistency and accessibility of laser energy are poor.

[0004] Electrical discharge machining technology uses the plasma generated after the microsecond pulse energy breaks down the dielectric to remove heat from the material. The temperature of the discharge channel can reach 10,000 K. In theory, any conductive material can be machined, and the duration of the energy is controllable. The non-contact material removal form of this technology does not generate macroscopic cutting force and has unique machining advantages for conductive ceramic matrix composites. The inter-electrode flushing condition can greatly reduce the thickness of the thermal affected zone. However, the surface after single electrical discharge machining has defects such as micro-cracks and pores, which are prone to peeling off under high temperature, high pressure, and alternating loads, seriously affecting the service life and performance of parts.

[0005] The existing combination of electrical discharge machining and grinding is restricted by the disordered distribution of abrasive grains on the tool electrode, and it is difficult to regulate the synergistic effect between the two. How to actively regulate the discharge energy and area to induce the generation of a loose layer rich in micro-cracks and pores that is easy to remove by grinding is of great strategic significance for the development of low-damage machining technology.

[0006] Based on the above analysis, a composite machining method for controllable discharge induced grinding of conductive ceramic-based composites is designed. Summary of the invention

[0007] The present invention aims to solve the above technical problems and provides a composite processing method for controllable discharge induced grinding of conductive ceramic-based composite materials.

[0008] In order to solve the above technical problems, the technical solution provided by the present invention is:

[0009] A composite processing method for controllable discharge induced grinding of conductive ceramic-based composite materials comprises the following steps:

[0010] ①, preparing a tool electrode with abrasive grains and a conductive substrate, so that the abrasive grains are fixed on the surface of the conductive substrate;

[0011] ② Spray the working medium into the processing area or immerse the conductive ceramic matrix composite material and the tool electrode into the working medium;

[0012] ③. Connect one pole of the pulse power supply to the tool electrode, and the other pole to the conductive ceramic-based composite material, and adjust the distance between the tool electrode and the surface of the conductive ceramic-based composite material until spark discharge occurs;

[0013] ④. Make the tool electrode move tangentially relative to the surface of the conductive ceramic-based composite material, at which time a discharge channel is generated between the tool electrode and the surface of the conductive ceramic-based composite material, inducing the surface of the material to be modified into a loose layer;

[0014] ⑤. At the same time, the tool electrode moves tangentially along the surface of the conductive ceramic-based composite material. As the tool electrode moves tangentially along the surface of the conductive ceramic-based composite material, the abrasive particles remove the loose layer;

[0015] ⑥, cycle steps ④ and ⑤ to achieve controllable discharge induction-grinding low-damage composite processing;

[0016] The conductive substrate is in the shape of a line, a column or a block;

[0017] The abrasive particles are arranged on the conductive substrate in a spiral or array shape.

[0018] Preferably, the abrasive particles are wear-resistant particles, and the particle size of the abrasive particles is between 100 mesh and 5000 mesh.

[0019] Preferably, the conductive substrate is made of a conductive material.

[0020] Preferably, when the conductive substrate is columnar or linear, the arrangement is a spiral arrangement, and when the conductive substrate is block-shaped, the arrangement is an array arrangement along the bottom and side surfaces of the block-shaped electrode.

[0021] Preferably, the distribution width d of the abrasive grains on the conductive substrate is 1-2 mm, the height h is 1-4 mm, and the angle α between the path of the abrasive grain arrangement and the horizontal is 20-60°.

[0022] Preferably, the state of the working medium can be liquid, gaseous or a gas-liquid mixture.

[0023] Preferably, the working medium is one or a combination of tap water, deionized water, kerosene, spark oil, air, nitrogen, carbon dioxide, etc., which can carry away the debris between the tool electrode and the surface of the material to be processed, provide an excellent discharge environment for the discharge-induced area, and avoid arc burning the material surface caused by debris accumulation. The output pressure of the working medium is 0.1-0.6 Mpa.

[0024] Preferably, the conductive ceramic matrix composite material is a continuous fiber-reinforced ceramic matrix composite material, and the weaving form is unidirectional, 2D or 2.5D.

[0025] Preferably, the voltage of the pulse power supply is 10-200 V, the pulse width is 1 μs-10 ms, and the pulse interval is 0.1-10 times the pulse width.

[0026] Preferably, the tangential movement can be the normal rotation of the tool electrode along the surface of the conductive ceramic matrix composite material, the rotation speed W1 is 1000-10000 revolutions per minute, or the tangential movement V1 along the surface of the material to be processed is 0.1 m / s-12 m / s, and the speed V2 of the tangential movement is 2 μm / s-1000 μm / s.

[0027] After adopting the above steps and methods, the present invention has the following advantages:

[0028] 1. The present invention induces the surface modification of the ceramic matrix composite material through controllable pulse energy, generates a loose layer with a controllable thickness, rich in microcracks and pores, greatly reduces the difficulty of grinding processing, reduces tool wear, and further inhibits the propagation of cracks.

[0029] 2. The abrasive grain area and the discharge area on the tool electrode of the present invention are staggered, which helps to actively regulate the discharge induction and grinding removal amount of the material, realizes the synchronous progress of discharge erosion and grinding removal, realizes the integrated processing of discharge and grinding, and improves the processing efficiency.

[0030] 3. The orderly distributed abrasive grains can play a role in strengthening mass transfer and promoting chip removal, which helps to improve the discharge stability.

[0031] 4. The present invention can achieve low-damage machining of conductive ceramic matrix composites, significantly reducing damage forms such as macroscopic brittle fracture of fibers, matrix fragmentation, and interfacial debonding; it provides a new method for low-damage machining of conductive ceramic matrix composites containing fiber reinforcement and high-temperature resistant structural components, and has important scientific research and engineering application values for the development of special energy field-assisted machining technologies.

[0032] The above summary is only for the purpose of the specification and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features of the present invention will be readily apparent by reference to the drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] 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 for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description 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.

[0034] Figure 1 is a schematic diagram of the processing principle of the present invention;

[0035] Figure 2 is a schematic diagram of the structure of the linear tool electrode of the present invention;

[0036] Figure 3 is a schematic diagram of the structure of the columnar tool electrode of the present invention;

[0037] Figure 4 is a schematic diagram of the structure of the block tool electrode of the present invention;

[0038] Figure 5 is a schematic diagram of the processing of the linear tool electrode of the present invention;

[0039] Figure 6 is a schematic diagram of the structure of the processing of the columnar tool electrode of the present invention;

[0040] Figure 7 is a schematic diagram of the structure of the processing of the block tool electrode of the present invention.

[0041] As shown in the figure: 1. Conductive ceramic matrix composite; 2. Abrasive grains; 3. Conductive matrix; 4. Working medium; 5. Debris; 6. Discharge channel; 7. Loose layer; 8. Tool electrode; 9. Pulse power supply; 10. Linear tool electrode; 11. Columnar tool electrode; 12. Block tool electrode; 13. Workbench; 14. Wire storage cylinder; 15. Spindle. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0042] Specific embodiments of the present invention will now be mentioned in detail. Although the present invention is described in conjunction with these specific embodiments, it should be appreciated that it is not intended to limit the present invention to these specific embodiments. On the contrary, these embodiments are intended to cover substitutions, changes or equivalent embodiments that may be included in the spirit and scope of the invention defined by the claims. In the following description, a large number of specific details are set forth in order to provide a comprehensive understanding of the present invention. The present invention can be implemented without some or all of these specific details. In other cases, in order not to make the present invention unnecessarily obscure, well-known process operations are not described in detail.

[0043] When used in conjunction with "including," "methods comprising," or similar language in this specification and the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0044] The present invention is further described in detail below in conjunction with the full text.

[0045] Combined with Figures 1 - 7 A composite processing method for controlled discharge induced grinding of conductive ceramic-based composite materials comprises the following steps:

[0046] ①, preparing a tool electrode 8 with abrasive grains 2 and a conductive substrate 3, so that the abrasive grains 2 are fixed on the surface of the conductive substrate 3;

[0047] ②, spraying the working medium 4 into the processing area or immersing the conductive ceramic matrix composite material 1 and the tool electrode 8 into the working medium 4;

[0048] ③. Connect one electrode of the pulse power supply 9 to the tool electrode 8 and the other electrode to the conductive ceramic-based composite material 1, and adjust the distance between the tool electrode 8 and the surface of the conductive ceramic-based composite material 1 until spark discharge occurs;

[0049] ④, making the tool electrode 8 move tangentially relative to the surface of the conductive ceramic-based composite material 1, at this time, a discharge channel 6 is generated between the tool electrode 8 and the surface of the conductive ceramic-based composite material 1, inducing the surface of the material to be modified into a loose layer 7;

[0050] ⑤. At the same time, the tool electrode 8 moves tangentially along the surface of the conductive ceramic-based composite material 1. As the tool electrode 8 moves tangentially along the surface of the conductive ceramic-based composite material 1, the abrasive particles 2 remove the loose layer 7;

[0051] ⑥, cycle steps ④ and ⑤ to achieve controllable discharge induction-grinding low-damage composite processing;

[0052] The conductive substrate 3 is in the shape of a line, a column or a block;

[0053] The arrangement form of the abrasive grains 2 on the conductive substrate 3 is spiral or array arrangement.

[0054] The abrasive grains 2 are wear-resistant particles. Specifically, the abrasive grains 2 are high-hardness wear-resistant particles, such as CBN, corundum, or diamond, etc. And the mesh number of the abrasive grains 2 is between 100 mesh and 5000 mesh. The maximum breakdown gap is determined according to the dielectric strength of the working medium 4, and thus the height of the abrasive grain protrusion and the grinding removal thickness are determined.

[0055] The material of the conductive substrate 3 is a conductive material, such as copper or molybdenum. The process of consolidating the abrasive grains 2 with the metal substrate is electroplating, laser cladding, or adhesive bonding.

[0056] When the conductive substrate 3 is columnar or linear, the arrangement form is spiral arrangement. When the conductive substrate 3 is block-shaped, the arrangement form is array arrangement along the bottom surface and side surface of the block-shaped electrode. The distribution width d of the abrasive grains 2 on the conductive substrate 3 is 1 - 2 mm and the height h is 1 - 4 mm. The angle α between the path of the arrangement of the abrasive grains 2 and the horizontal is 20 - 60°. Specifically, the arrangement form of the abrasive grains 2 on the conductive substrate 3 is spiral or array arrangement. When the conductive substrate 3 is columnar or linear, it is spiral arrangement. When the conductive substrate 3 is block-shaped, it is array arrangement along the bottom surface and side surface of the block-shaped electrode. The angle α between the path of the arrangement of the abrasive grains and the horizontal is 20 - 60°. The spiral arrangement of the abrasive grains 2 can increase the chip space between the tool electrode 8 and the surface of the conductive ceramic matrix composite material 1, and play the role of transporting debris 5 and strengthening the mass transfer of the working medium 4.

[0057] The state of the working medium 4 can be liquid, gas, or gas-liquid mixture. The working medium 4 is one or a combination of tap water, deionized water, kerosene, spark oil, air, nitrogen, carbon dioxide, etc. It can take away the debris between the tool electrode and the surface of the material to be processed, provide an excellent discharge environment for the discharge-induced area, and avoid arc burning on the material surface caused by debris accumulation. The output pressure of the working medium 4 is 0.1 - 0.6 Mpa.

[0058] The conductive ceramic matrix composite material 1 is a continuous fiber-reinforced ceramic matrix composite material and the weaving form is unidirectional, 2D, or 2.5D, such as 2D Cf / SiC, 2D SiCf / SiC. The material of the conductive ceramic matrix composite material 1 is a conductive material, which can be a material with conductive fibers, a conductive matrix, or a material that realizes conductivity through doping technology. Among them, the conductive fiber is a fiber with conductivity, such as common carbon fiber, SiC fiber; the matrix is a material with conductivity, such as common carbon matrix or SiC matrix.

[0059] The voltage of the pulse power supply 9 is 10 - 200V, the pulse width is 1μs - 10ms, and the pulse interval is 0.1 - 10 times the pulse width. One pole of the pulse power supply 9 connected to the tool electrode 8 can be the positive or negative pole, and the appropriate polarity is selected according to the material properties of the material to be processed and the tool electrode.

[0060] Specifically, the tangential movement can be that the tool electrode 8 rotates self - clockwise along the normal direction of the surface of the conductive ceramic matrix composite material 1, with a rotational speed W1 of 1000 - 10000 revolutions per minute, or the tangential movement along the surface of the material to be processed V1 is 0.1m / s - 12m / s, and the speed of the tangential movement V2 is 2μm / s - 1000μm / s.

[0061] Through the modification of the conductive induced ceramic matrix composite material 1, the surface of the present invention becomes a loose layer rich in micro - cracks and pores, providing conditions for efficient and low - damage grinding removal, and solving the problems existing in the processing and manufacturing of ceramic matrix composite materials, especially ceramic matrix composite materials containing fiber - reinforced phases, such as serious matrix fragmentation, macroscopic brittle fracture of fibers, and interfacial debonding damage, accompanied by serious tool wear, low processing efficiency, and high processing costs.

[0062] The medium condition required by the electric discharge machining technology of the present invention plays a cooling role, greatly reducing the thickness of the heat - affected zone. It solves the problems that the current laser - energy - field composite grinding is restricted by the structural form of the workpiece to be processed, the poor consistency of laser energy, and the poor accessibility of the laser, and the thick heat - affected zone under the thermal accumulation effect of laser energy.

[0063] By changing the distribution of the abrasive grains 2 of the tool electrode, the present invention makes the discharge - induced zone and the grinding - removal zone stagger and distribute, realizing the orderly progress of the action of first inducing and then grinding, and solving the problems that the traditional discharge - grinding composite machining cannot achieve benign cooperative machining, cannot actively regulate the discharge energy and area, and essentially cannot exert the inducing effect of the discharge.

[0064] The present invention provides a composite machining method for controllable discharge - induced grinding of conductive ceramic matrix composite materials. The material targeted is the conductive ceramic matrix composite material 1, which is a high - performance composite material composed of a ceramic matrix and a continuous fiber - reinforced phase, and has both the high temperature - resistance and corrosion - resistance characteristics of ceramics and the high strength and high toughness of fibers. The specific steps of this machining method are as follows:

[0065] Before the processing begins, a tool electrode 8 is made of abrasive grains 2 and a linear, columnar or block-shaped conductive substrate 3. The outer surface of the abrasive grains 2 is subjected to chemical nickel plating to turn the abrasive grains 2 into particles with conductive outer surfaces. Then, an insulating tape is attached to the surface of the conductive substrate 3 for insulation treatment, and a spiral conductive area is left. The abrasive grains 2 and the conductive substrate 3 are placed in a plating solution containing nickel salt for electroplating, and a dispersant is added to prevent the abrasive grains 2 from agglomerating. At this time, the abrasive grains 2 adhere to the conductive substrate along the spiral conductive area remaining on the conductive substrate 3. The insulating tape on the conductive substrate 3 is removed, and the abrasive grains 2 are The arrangement form on the conductive substrate 3 is spiral. When the conductive substrate 3 is columnar or linear, it is spirally arranged. When the conductive substrate 3 is blocky, it is arranged in an array along the bottom and side surfaces of the block electrode. The spiral arrangement of the abrasive particles 2 can increase the chip space between the tool electrode 8 and the surface of the conductive ceramic-based composite material 1, and play a role in transmitting debris 5 and strengthening the mass transfer of the working medium 4. The h of the abrasive particles 2 on the conductive substrate 3 is 1 mm, and d is 2 mm. The angle α between the path of the abrasive particle arrangement and the horizontal is 30°. The linear tool electrode 10, the columnar tool electrode 11 or the block tool electrode 12 is prepared. Figures 2 - 4 shown.

[0066] Embodiment 1:

[0067] This embodiment uses a linear tool electrode 10, such as Figure 5 As shown, in the linear tool electrode 10, the linear tool electrode 10 is wound on the wire storage drum 14, wherein the linear tool electrode 10 can realize reciprocating motion, and the positive and negative electrodes of the high-frequency pulse power supply 9 are respectively connected to the linear tool electrode 10 and the conductive ceramic-based composite material 1. After everything is ready, the working medium 4 is sprayed between the linear tool electrode 10 and the conductive ceramic-based composite material 1, and the distance between the tool electrode 10 and the conductive ceramic-based composite material 1 is adjusted until a discharge breakdown phenomenon occurs in the gap, that is, a discharge channel 6 is formed, and then the automatic feed switch of the workbench is turned on, so that the workbench 13 is fed along the normal direction of the processing surface at a speed of V2 (10μm / s); the automatic feed starts After that, at a certain moment, since the abrasive particles 2 are spirally distributed on the tool electrode 8, there is a part of the surface of the conductive ceramic-based composite material 1 facing the area of ​​the tool electrode 8 without the abrasive particles 2. The area is being broken down by the electric spark, and the material surface of the area is modified by the electric spark and becomes a loose layer 7 containing cracks and pores. At the next moment, with the movement of the tool electrode 8, the loose layer 7 contacts the abrasive particles on the tool electrode 8, and the abrasive particles 2 easily remove the loose layer 7. The loose layer rich in cracks and pores greatly reduces the grinding force during the grinding process, inhibits the generation and expansion of cracks, and avoids the macroscopic brittle fracture of continuous fibers, thereby achieving low-damage processing.

[0068] Embodiment 2:

[0069] In this embodiment, a columnar tool electrode 11 is adopted. As Figure 6 shown, the columnar tool electrode 11 is clamped on a rotatable spindle 15. Then, the conductive ceramic matrix composite material 1 is fixed on the workbench 13. The positive and negative electrodes of the high-frequency pulse power supply 9 are respectively connected to the columnar tool electrode 11 and the conductive ceramic matrix composite material 1. Then, a working medium 4 is sprayed between the columnar tool electrode 11 and the conductive ceramic matrix composite material 1. The distance between the columnar tool electrode 11 and the conductive ceramic matrix composite material 1 is adjusted until a discharge breakdown phenomenon occurs in the gap. Then, the automatic feed switch of the spindle 15 is turned on, and the columnar tool electrode 11 feeds towards the conductive ceramic matrix composite material 1 at a speed of V1 (1 m / s). At the same time, the columnar tool electrode 11 rotates self - clockwise at a speed of W1, so that while the columnar tool electrode 11 rotates self - clockwise, it moves tangentially relative to the surface of the conductive ceramic matrix composite material at a speed of V1 (1 m / s). After the start of automatic feeding, at a certain instant, since the abrasive grains 2 are helically distributed on the tool electrode 8, there is a part of the surface of the conductive ceramic matrix composite material 1 facing the area of the tool electrode 8 without abrasive grains 2. The area between them is being broken down by electric sparks, and the surface of the material in this area is modified by the electric sparks and becomes a porous layer 7 containing cracks and pores. At the next instant, as the tool electrode 8 moves, the porous layer 7 comes into contact with the abrasive grains on the tool electrode 8, and the abrasive grains 2 easily remove the porous layer 7. The porous layer rich in cracks and pores greatly reduces the grinding force during the grinding process, inhibits the generation and propagation of cracks, and avoids the macroscopic brittle fracture of continuous fibers, thereby enabling low - damage machining.

[0070] Embodiment Three:

[0071] In this embodiment, a block - shaped tool electrode 12 is adopted. As Figure 7As shown, the block-shaped tool electrode 12 is clamped on the spindle 15. Then, the conductive ceramic matrix composite material 1 is fixed on the workbench 13. The positive and negative electrodes of the high-frequency pulse power supply 9 are respectively connected to the block-shaped tool electrode 12 and the conductive ceramic matrix composite material 1. Then, the working medium 4 is sprayed between the block-shaped tool electrode 12 and the conductive ceramic matrix composite material 1. The distance between the block-shaped tool electrode 12 and the conductive ceramic matrix composite material 1 is adjusted until a discharge breakdown phenomenon occurs in the gap. Then, the automatic feed switch of the spindle 15 is turned on. The block-shaped tool electrode 12 moves tangentially along the surface of the conductive ceramic matrix composite material 1 at a speed V2 (10 μm / s), or feeds tangentially along the surface of the conductive ceramic matrix composite material 1 in combination with the speed V1 (1 m / s). After the automatic feed starts, at a certain instant, since the abrasive grains 2 are spirally distributed on the tool electrode 8, there is a part of the area on the surface of the conductive ceramic matrix composite material 1 that is facing the area of the tool electrode 8 without abrasive grains 2. The area between them is being broken down by electric sparks, and the surface of the material in this area is modified by the electric sparks and becomes a porous layer 7 containing cracks and pores. At the next instant, as the tool electrode 8 moves, the porous layer 7 comes into contact with the abrasive grains on the tool electrode 8, and the abrasive grains 2 easily remove the porous layer 7. The porous layer rich in cracks and pores greatly reduces the grinding force during the grinding process, inhibits the generation and propagation of cracks, and avoids the macroscopic brittle fracture of continuous fibers, thereby enabling low-damage machining.

[0072] The above describes the present invention and its embodiments. Such a description is not restrictive. What is shown throughout the text is only one of the embodiments of the present invention, and the actual structure is not limited thereto. In short, if those of ordinary skill in the art are inspired by it and, without departing from the spirit of the present invention, design similar structural forms and embodiments to this technical solution without creative efforts, they shall fall within the protection scope of the present invention.

Claims

1. A composite processing method for controlled discharge induced grinding of conductive ceramic-based composite materials, characterized in that: The following steps are involved: ①, preparing a tool electrode (8) using abrasive grains (2) and a conductive substrate (3), so that the abrasive grains (2) are fixed on the surface of the conductive substrate (3); ②, spraying a working medium (4) into the processing area or immersing the conductive ceramic-based composite material (1) and the tool electrode (8) into the working medium (4); ③. Connect one electrode of the pulse power supply (9) to the tool electrode (8), and the other electrode to the conductive ceramic-based composite material (1), and adjust the distance between the tool electrode (8) and the surface of the conductive ceramic-based composite material (1) until spark discharge occurs; ④, making the tool electrode (8) move tangentially relative to the surface of the conductive ceramic-based composite material (1), thereby generating a discharge channel (6) between the tool electrode (8) and the surface of the conductive ceramic-based composite material (1), inducing the surface of the material to be modified into a loose layer (7); 5. At the same time, the tool electrode (8) moves tangentially along the surface of the conductive ceramic-based composite material (1). As the tool electrode (8) moves tangentially along the surface of the conductive ceramic-based composite material (1), the abrasive grains (2) remove the loose layer (7); ⑥, cycle steps ④ and ⑤ to achieve controllable discharge induction-grinding low-damage composite processing; The conductive substrate (3) is in the shape of a line, a column or a block; The abrasive particles (2) are arranged on the conductive substrate (3) in a spiral or array arrangement.

2. The composite processing method of controlled discharge induced grinding of conductive ceramic-based composite materials according to claim 1, characterized in that: The abrasive particles (2) are wear-resistant particles, and the particle size of the abrasive particles (2) is between 100 mesh and 5000 mesh.

3. The composite processing method of controlled discharge induced grinding of conductive ceramic-based composite materials according to claim 1, characterized in that: The conductive substrate (3) is made of a conductive material.

4. The composite processing method of controlled discharge induced grinding of conductive ceramic-based composite materials according to claim 1, characterized in that: When the conductive substrate (3) is in columnar or linear form, the arrangement is in spiral arrangement; when the conductive substrate (3) is in block form, the arrangement is in array arrangement along the bottom and side surfaces of the block electrode.

5. The composite processing method of controlled discharge induced grinding of conductive ceramic-based composite materials according to claim 4, characterized in that: The distribution width d of the abrasive grains (2) on the conductive substrate (3) is 1-2 mm and the height h is 1-4 mm. The angle α between the arrangement path of the abrasive grains (2) and the horizontal is 20-60°.

6. The composite processing method of controlled discharge induced grinding of conductive ceramic-based composite materials according to claim 1, characterized in that: The working medium (4) may be in a liquid state, a gaseous state or a gas-liquid mixed state.

7. The composite processing method of controlled discharge induced grinding of conductive ceramic-based composite materials according to claim 6, characterized in that: The working medium (4) is one or a combination of tap water, deionized water, kerosene, spark oil, air, nitrogen, and carbon dioxide, and can remove debris between the tool electrode and the surface of the material to be processed, provide an excellent discharge environment for the discharge induction area, and avoid debris accumulation to cause arcing and burn the material surface. The output pressure of the working medium (4) is 0.1-0.6Mpa.

8. The composite processing method of controlled discharge induced grinding of conductive ceramic-based composite materials according to claim 6, characterized in that: The conductive ceramic-based composite material (1) is a continuous fiber-reinforced ceramic-based composite material and has a weaving form of unidirectional, 2D or 2.5D.

9. The composite processing method of controlled discharge induced grinding of conductive ceramic-based composite materials according to claim 6, characterized in that: The voltage of the pulse power supply (9) is 10-200V, the pulse width is 1μs-10ms, and the pulse interval is 0.1-10 times of the pulse width.

10. The composite processing method of controlled discharge induced grinding of conductive ceramic-based composite materials according to claim 6, characterized in that: The tangential motion may be the normal rotation of the tool electrode (8) along the surface of the conductive ceramic-based composite material (1), with a rotation speed W1 of 1000-10000 rpm, or a tangential motion V1 of 0.1 m / s-12 m / s along the surface of the material to be processed, with a speed V2 of 2 μm / s-1000 μm / s.

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