Electro-pulse assisted cutting-rolling composite surface strengthening device and processing method

Abstract

The application discloses an electric pulse assisted cutting-rolling composite surface strengthening device and a machining method, and relates to the technical field of metal material surface treatment. The device comprises a rolling device and an electric pulse assisted turning device. The rolling device comprises a fixed base, a mounting sleeve and a rolling assembly. The inner cavity of the mounting sleeve is uniformly provided with a plurality of rolling assemblies in the circumferential direction. The rolling assembly comprises a floating base, a rolling base, a guide cylinder and a rolling end cover which are connected in sequence. A spherical cavity is formed between the guide cylinder and the rolling end cover, and a ball is installed in the spherical cavity. The electric pulse assisted turning device comprises a first electric brush and a second electric brush. The first electric brush is installed on the bed and is in contact with the chuck mechanism. The second electric brush is installed on the fixed base and is used for contacting the workpiece. The first electric brush and the second electric brush are respectively connected with the positive electrode and the negative electrode of the pulse power supply. The application introduces the electric pulse treatment into the cutting process, can strengthen the rolling effect, can reduce the thermal stress and thermal deformation during rolling, and can improve the machining precision.

Description

Technical Field

[0001] This invention relates to the field of surface treatment technology for metallic materials, and in particular to an electropulse assisted cutting-rolling composite surface strengthening device and processing method. Background Technology

[0002] In today's era of rapid technological development, the progress of manufacturing relies heavily on the support of advanced technologies and equipment. Cutting technology and equipment, as the foundation of manufacturing, directly impact the competitiveness of the entire industry. In recent years, with the advancement of modern science and technology, higher demands have been placed on the surface properties of materials and components. Simply relying on rolling technology is no longer sufficient to meet the high-performance requirements of equipment for parts.

[0003] Currently, the main rolling processes include ultrasonic vibration-assisted rolling and laser-assisted rolling, which increase equipment investment and raise the processing cost of parts. The preceding process in the rolling process is often machining; existing machining techniques form a thin, high-dislocation-density, high-work-hardening modified layer on the workpiece surface, which has little positive impact on the rolling process. Furthermore, during rolling, the workpiece and cutting tool generate a large amount of heat, making the workpiece prone to thermal stress and deformation, which adversely affects the machining accuracy.

[0004] Based on this, the inventors propose an electropulse-assisted cutting-rolling composite surface strengthening device and processing method to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide an electrical pulse-assisted cutting-rolling composite surface strengthening device and processing method to solve the problems existing in the prior art. By introducing electrical pulse treatment into the cutting process, the dislocation density on the surface of the workpiece is reduced, the grains are significantly refined, and the thickness of the modified layer is increased. This promotes dynamic recrystallization during the rolling process. In the heat and mass transfer process, a workpiece surface hardened layer with further refined grains and doubled thickness is formed on the workpiece surface, which enhances the rolling effect and reduces thermal stress and thermal deformation during rolling, thereby improving processing accuracy.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] This invention provides an electro-pulse assisted cutting-rolling composite surface strengthening device, including a machine tool, wherein a chuck mechanism and a tailstock mechanism are respectively provided at the head and tail ends of the machine tool, and a slide box is provided between the chuck mechanism and the tailstock mechanism; it also includes a rolling device and an electro-pulse assisted turning device.

[0008] The rolling device includes a fixed base, a mounting sleeve, and rolling components. The fixed base is installed on the upper end of the slide box, and the mounting sleeve is installed on the fixed base. The central axis of the mounting sleeve is collinear with the line connecting the center of the chuck mechanism and the tip of the tailstock mechanism. The mounting sleeve is located on the side of the tool holder away from the chuck mechanism. Multiple rolling components are evenly arranged circumferentially in the inner cavity of the mounting sleeve.

[0009] The rolling assembly includes a floating base, a rolling base, a guide cylinder, and a rolling end cap connected in sequence. The floating base is fitted into a groove in the inner cavity of the mounting sleeve. A spherical cavity is formed between the guide cylinder and the rolling end cap. A ball bearing is installed in the spherical cavity and protrudes outward from the rolling end cap for rolling the workpiece. The interiors of the floating base, the rolling base, the guide cylinder, and the rolling end cap are interconnected to form a coolant channel. The end face of the rolling end cap is provided with multiple liquid outlet holes. The side wall of the mounting sleeve is provided with liquid guiding channels that correspond one-to-one with and communicate with the coolant channels of each of the rolling assemblies. The coolant is sprayed onto the workpiece rolling part through the liquid outlet holes via the liquid guiding channels and the coolant channels.

[0010] The electropulse-assisted turning device includes a first brush and a second brush. The first brush is mounted on the machine bed and contacts the chuck mechanism. The second brush is mounted on the fixed base and contacts the workpiece. The first brush and the second brush are respectively connected to the positive and negative terminals of the pulse power supply.

[0011] Preferably, both the first brush and the second brush are provided with magnets, and the first brush and the second brush are magnetically attached to the bed and the fixed base, respectively. The second brush is located between the cutting tool on the tool holder and the mounting sleeve.

[0012] Preferably, the mounting sleeve includes a mounting assembly, an adjusting sleeve, a limiting ring, and an end cap. The mounting assembly is mounted on the fixed base. The adjusting sleeve is threaded to one end of the mounting assembly. The end cap is mounted on the other end of the mounting assembly. The end of the mounting assembly near the adjusting sleeve has a T-shaped groove that slides with the floating base. The T-shaped groove is inclined inward from the end near the adjusting sleeve to the end away from the adjusting sleeve. The two ends of the floating base abut against the mounting assembly and the limiting ring, respectively. The limiting ring is slidably disposed coaxially in the inner cavity of the mounting assembly. The limiting ring is located between the floating base and the end cap. A first spring is provided between the limiting ring and the end cap. The two ends of the first spring abut against the limiting ring and the end cap, respectively. Under the elastic force of the first spring, the floating base can be moved along the T-shaped groove by twisting the adjusting sleeve to move closer to or further away from the center of the mounting assembly, thereby adjusting the rolling diameter.

[0013] Preferably, the floating base has a boss on the end face near the limiting ring. The boss is located in the inner cavity of the limiting ring. When the rolling diameter is at its maximum, the boss abuts against the inner cylindrical surface of the limiting ring.

[0014] Preferably, the inner cylindrical surface of the guide cylinder is provided with an annular groove, and a sealing ring is installed in the annular groove. The guide cylinder is sealed to the rolling base through the sealing ring. A second spring is provided between the guide cylinder and the rolling base. The two ends of the second spring abut against the inner bottom surface of the guide cylinder and the step on the rolling base, respectively. The guide cylinder and the rolling end cap are connected by threads.

[0015] Preferably, the outer cylindrical surface of the guide cylinder is provided with scale lines to display the rolling pressure in conjunction with the end face of the rolling base.

[0016] Preferably, each of the outer ports of the liquid guiding channels is threaded with a coolant injection port.

[0017] Preferably, the opening at the end of the floating base that is connected to the liquid guiding channel is larger than the port of the liquid guiding channel, so that the floating base is always in communication with the liquid guiding channel during movement; the opening at the end of the floating base that is connected to the rolling base is the same size as the liquid guiding channel.

[0018] Preferably, each of the liquid outlet holes is evenly distributed on the end face of the rolling end cover, and the axis of each of the liquid outlet holes forms an angle with the central axis of the rolling end cover, so that the coolant can be directly sprayed onto the rolling part through the liquid outlet holes.

[0019] This invention also provides an electropulse-assisted cutting-rolling composite surface strengthening method, based on the electropulse-assisted cutting-rolling composite surface strengthening device described above, comprising the following steps:

[0020] (1) The workpiece to be rolled passes through the inner cavity of the mounting sleeve. One end of the workpiece is clamped and fixed by the chuck mechanism, and the other end is positioned by the center. The machine tool is controlled to move the slide box, which drives the cutting tool and the rolling device to move, and moves the cutting tool and the ball to the starting position of the workpiece machining.

[0021] (2) Adjust the rolling assembly to a suitable position according to process requirements;

[0022] (3) Turn on the pulse power supply and start injecting coolant from the liquid channel, turn on the machine tool spindle, and perform turning and rolling continuously until the workpiece is finished.

[0023] (4) Turn off the rotation of the machine tool spindle, retract the cutting tool and the mounting sleeve to the vicinity of the center, and check the machining status;

[0024] (5) If the processing quality meets the requirements, turn off the pulse power supply and stop injecting coolant;

[0025] (6) Remove the workpiece, install the next workpiece, and repeat the above steps.

[0026] The present invention achieves the following technical effects compared to the prior art:

[0027] This invention incorporates a first brush and a second brush on the machine tool, creating a current loop in the workpiece during turning. On one hand, the electroplastic effect of the electrical pulse promotes dislocation annihilation, accelerates dynamic recrystallization, reduces the workpiece's hardness and strength, and improves its plasticity. On the other hand, the pulsed current generates electron flow between the tool-chip / workpiece friction pair, producing sliding electrical contact and reducing the coefficient of friction between the pairs. This significantly improves the machinability of the workpiece material and enhances its surface quality.

[0028] This invention incorporates a rolling device on a machine tool, with the rolling components mounted on an apron via a fixed base, minimizing impact on the turning process. The machine tool can simultaneously perform electrical pulse-assisted turning and rolling. While improving production efficiency, the electrical pulse-assisted turning creates an ultra-thick, ultra-fine crystalline modified layer on the workpiece surface, reducing the critical strain for dynamic recrystallization during the rolling process. This promotes dynamic recrystallization, further refining the grains, reducing dislocations, and deepening the hardened layer on the rolled workpiece surface, thus significantly enhancing the strengthening effect.

[0029] This invention includes a cooling system. Coolant is sprayed onto the workpiece rolling area through a liquid outlet via a guide channel and a coolant channel. The coolant absorbs and carries away the heat generated during machining, effectively reducing the temperature of the workpiece and tool, minimizing thermal stress and deformation, thereby improving machining accuracy. Secondly, the coolant forms a lubricating film between the workpiece and tool, helping to reduce the coefficient of friction in the rolling area, reducing rolling pressure, thus improving machining quality and extending tool life. Simultaneously, the shape and position of the coolant channels minimize the impact of the cooling system on turning and rolling processes.

[0030] The inner cavity of the mounting sleeve of the present invention has multiple rolling components evenly distributed. The balls of each rolling component can roll the workpiece from multiple different parts at the same time. Compared with the traditional rolling method, this arrangement improves the rolling efficiency and rolling quality on the one hand, and avoids the deformation of the part caused by uneven rolling force of a single ball, thus avoiding the impact on the workpiece processing.

[0031] Furthermore, the inclined arrangement of the T-shaped groove in the inner cavity of the present invention allows the rolling assembly to slide radially, thereby changing the rolling diameter and adapting well to the rolling process of workpieces with different diameters.

[0032] Furthermore, the opening at the end of the floating base connected to the liquid guiding channel is larger than the port of the liquid guiding channel, so that the floating base is always connected to the liquid guiding channel during movement, ensuring the normal operation of the cooling function while the rolling device meets the rolling requirements of workpieces of different diameters.

[0033] Furthermore, the outer cylinder of the guide tube of the present invention is provided with scale lines, which are used to cooperate with the end face of the rolling base to display the rolling pressure, so that the rolling pressure can be monitored in real time during the rolling process, and the rolling diameter can be changed by adjusting the adjusting sleeve according to the process requirements, thereby achieving the purpose of controlling the rolling pressure. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of the overall structure of the electropulse-assisted cutting-rolling composite surface strengthening device in an embodiment of the present invention;

[0036] Figure 2 This is a partial cross-sectional view of the electropulse-assisted cutting-rolling composite surface strengthening device in an embodiment of the present invention;

[0037] Figure 3 This is a half-sectional view of the mounting sleeve in an embodiment of the present invention;

[0038] Figure 4 for Figure 3 A magnified view of part B in the middle section;

[0039] Figure 5 This is a schematic diagram of the connection structure between the fitting and the rolling assembly in this invention;

[0040] Figure 6 This is a top view of the electropulse-assisted cutting-rolling composite surface strengthening device in an embodiment of the present invention;

[0041] Figure 7 for Figure 6 Side view along the AA direction;

[0042] Figure 8 This is a schematic diagram of the assembly structure in an embodiment of the present invention;

[0043] Figure 9 This is a schematic diagram of the structure of the floating base in an embodiment of the present invention.

[0044] In the diagram: 1-Machine tool, 2-Chuck mechanism, 3-Tailstock mechanism, 4-Slide box, 5-Rolling device, 6-Fixed base, 7-Mounting sleeve, 8-Rolling assembly, 9-Center, 10-Tool post, 11-Floating base, 12-Rolling base, 13-Guide cylinder, 14-Rolling end cover, 15-Ball bearing, 16-Workpiece, 17-Liquid outlet hole, 18-Liquid channel, 19-First brush, 20-Second brush, 21-Lathe tool, 22-Assembly, 23-Adjusting sleeve, 24-Limiting ring, 25-End cover, 26-T-groove, 27-First spring, 28-Boss, 29-Sealing ring, 30-Second spring, 31-Coolant injection port, 32-First end opening, 33-Second end opening, 34-Through hole, 35-Set screw. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] The purpose of this invention is to provide an electrical pulse-assisted cutting-rolling composite surface strengthening device and processing method to solve the problems existing in the prior art. By introducing electrical pulse treatment into the cutting process, the dislocation density on the surface of the workpiece is reduced, the grains are significantly refined, and the thickness of the modified layer is increased. This promotes dynamic recrystallization during the rolling process. In the heat and mass transfer process, a workpiece surface hardened layer with further refined grains and doubled thickness is formed on the workpiece surface, which enhances the rolling effect and reduces thermal stress and thermal deformation during rolling, thereby improving the processing accuracy.

[0047] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0048] like Figures 1-9 As shown, this embodiment provides an electro-pulse assisted cutting-rolling composite surface strengthening device, including a machine tool 1. The machine tool 1 has a chuck mechanism 2 and a tailstock mechanism 3 at its head and tail ends, respectively. A slide box 4 is provided between the chuck mechanism 2 and the tailstock mechanism 3. The chuck mechanism 2 is a three-jaw chuck. The device also includes a rolling device 5 and an electro-pulse assisted turning device.

[0049] The rolling device 5 includes a fixed base 6, a mounting sleeve 7, and rolling components 8. The fixed base 6 is installed on the upper end of the slide box 4 by a threaded connection. The mounting sleeve 7 is installed on the fixed base 6 by a threaded connection. The central axis of the mounting sleeve 7 is collinear with the line connecting the center of the chuck mechanism 2 and the tip 9 of the tailstock mechanism 3. The mounting sleeve 7 is located on the side of the tool holder 10 away from the chuck mechanism 2. The inner cavity of the mounting sleeve 7 is uniformly provided with multiple rolling components 8 along the circumference; specifically, this embodiment provides 3 rolling components 8.

[0050] The rolling assembly 8 includes a floating base 11, a rolling base 12, a guide cylinder 13, and a rolling end cap 14 connected in sequence. The floating base 11 is fitted into a groove in the inner cavity of the mounting sleeve 7. The rolling base 12 is coaxially fitted with the guide cylinder 13. A spherical cavity is formed between the guide cylinder 13 and the rolling end cap 14. Ball bearings 15 are installed in the spherical cavity and protrude outward from the rolling end cap 14 for rolling the workpiece 16. By evenly distributing the rolling assembly 8 circumferentially, each ball bearing 15 can apply the same rolling force to the workpiece 16, thereby improving the rolling quality. The floating base 11, the rolling base 12, the guide cylinder 13 and the rolling end cover 14 are internally connected to form a coolant channel. The end face of the rolling end cover 14 is provided with multiple liquid outlet holes 17. Specifically, in this embodiment, there are 4 liquid outlet holes 17. The side wall of the mounting sleeve 7 is provided with liquid guiding channels 18 that correspond one-to-one with and are connected to the coolant channels of each rolling component 8. The coolant is sprayed from the liquid outlet holes 17 to the rolling part of the workpiece 16 through the liquid guiding channels 18 and the coolant channels. The planes where the three liquid guiding channels 18 are located are spaced 120° apart from each other.

[0051] The electrical pulse-assisted turning device includes a first brush 19 and a second brush 20. The first brush 19 is mounted on the machine bed and contacts the chuck mechanism 2. The second brush 20 is mounted on the fixed base 6 and is used to contact the workpiece 16. The first brush 19 and the second brush 20 are respectively connected to the positive and negative terminals of the pulse power supply.

[0052] This invention introduces electrical pulse processing into the cutting process, reducing the dislocation density on the workpiece surface, significantly refining the grains, and increasing the thickness of the modified layer. This promotes dynamic recrystallization during the rolling process, and in the heat and mass transfer process, it forms a workpiece surface hardened layer with further refined grains and doubled thickness, enhancing the rolling effect. Furthermore, it can absorb and remove the heat generated during processing through the coolant, effectively reducing the temperature of the workpiece and tool, reducing thermal stress and thermal deformation, thereby improving machining accuracy.

[0053] In this embodiment, both the first brush 19 and the second brush 20 are provided with magnets. The first brush 19 and the second brush 20 are magnetically attracted to the bed and the fixed base 6, respectively. The second brush 20 is located between the cutting tool 21 and the mounting sleeve 7 on the tool holder 10.

[0054] In this embodiment, the mounting sleeve 7 includes a mounting sleeve 22, an adjusting sleeve 23, a limiting ring 24, and an end cap 25. The mounting sleeve 22 is mounted on the fixed base 6. The adjusting sleeve 23 is threaded to one end of the mounting sleeve 22. The end cap 25 is mounted on the other end of the mounting sleeve 22. The end of the mounting sleeve 22 near the adjusting sleeve 23 is provided with a T-shaped groove 26 that slides with the floating base 11. The T-shaped groove 26 is inclined inward from the end near the adjusting sleeve 23 to the end away from the adjusting sleeve 23. The two ends of the floating base 11 abut against the mounting sleeve 22 and the limiting ring 24, respectively. The limiting ring 24 is slidably mounted on the mounting sleeve along the same axis. The inner cavity of 22 has a limiting ring 24 located between the floating base 11 and the end cover 25. A first spring 27 is provided between the limiting ring 24 and the end cover 25. The two ends of the first spring 27 abut against the limiting ring 24 and the end cover 25 respectively. The first spring 27 and the limiting ring 24 are coaxial. Under the elastic force of the first spring 27, the floating base 11 can be moved along the T-shaped groove 26 by turning the adjusting sleeve 23 to move closer to or away from the center of the assembly 22, thereby adjusting the rolling diameter. The adjusting sleeve 23 is provided with a set screw 35. After the adjustment is in place, the set screw 35 is tightened to lock the adjusting sleeve 23 onto the assembly 22.

[0055] In this embodiment, a boss 28 is provided on the end face of the floating base 11 near the limiting ring 24. The boss 28 is located in the inner cavity of the limiting ring 24. When the rolling diameter is at its maximum, the boss 28 abuts against the inner cylindrical surface of the limiting ring 24. This improves the reliability of the device and prevents the floating base 11 from detaching due to improper operation by the operator.

[0056] In this embodiment, the inner cylindrical surface of the guide cylinder 13 is provided with an annular groove, and a sealing ring 29 is installed in the annular groove. The guide cylinder 13 is sealed to the rolling base 12 through the sealing ring 29. A second spring 30 is provided between the guide cylinder 13 and the rolling base 12. The two ends of the second spring 30 abut against the inner bottom surface of the guide cylinder 13 and the step on the rolling base 12, respectively. The guide cylinder 13 is connected to the rolling end cap 14 by threads.

[0057] In this embodiment, the outer cylindrical surface of the guide cylinder 13 is provided with scale lines, which are used to display the rolling pressure in conjunction with the end face of the rolling base 12. During the rolling process, the rolling pressure can be monitored in real time, and the rolling diameter can be changed by adjusting the adjusting sleeve 23 according to process requirements, thereby achieving the purpose of controlling the rolling pressure.

[0058] In this embodiment, each liquid guiding channel 18 has a coolant injection port 31 threadedly connected to its outer port. Coolant is injected into the liquid guiding channel 18 through the coolant injection port 31.

[0059] In this embodiment, the opening (first end opening 32) at the end of the floating base 11 that is connected to the liquid guiding channel 18 is larger than the port of the liquid guiding channel 18, so that the floating base 11 is always connected to the liquid guiding channel 18 during movement, which can well adapt to the structure of the floating base 11 changing the rolling diameter by moving in the groove; the opening (second end opening 33) at the end of the floating base 11 that is connected to the rolling base 12 is the same size as the liquid guiding channel 18.

[0060] In this embodiment, the guide cylinder 13 is provided with a plurality of through holes 34 evenly on the end face near the rolling end cover 14. Specifically, there are 4 through holes 34. Each through hole 34 can ensure that the coolant can flow from the guide cylinder 13 into the rolling end cover 14, and then flow normally to the workpiece 16 through the liquid outlet through hole 17.

[0061] In this embodiment, each liquid outlet hole 17 is evenly distributed on the end face of the rolling end cover 14, and the axis of each liquid outlet hole 17 has an angle with the central axis of the rolling end cover 14, so that the coolant can be directly sprayed into the rolling part at an angle through the liquid outlet hole 17.

[0062] An electro-pulse assisted cutting-rolling composite surface strengthening method, based on the electro-pulse assisted cutting-rolling composite surface strengthening device described above, includes the following steps:

[0063] (1) The workpiece 16 to be rolled passes through the inner cavity of the mounting sleeve 7. One end of the workpiece 16 is clamped and fixed by the chuck mechanism 2, and the other end is positioned by the center 9. Control the machine tool 1 to move the slide box 4, which drives the cutting tool 21 and the rolling device 5 to move, and moves the cutting tool 21 and the ball 15 to the starting position of the machining of the workpiece 16.

[0064] (2) Rotate the adjusting sleeve 23 to the appropriate position according to the process requirements and the reading on the guide cylinder 13, tighten the set screw 35, and adjust the rolling assembly 8 to the appropriate position.

[0065] (3) Turn on the pulse power switch and start injecting coolant into the coolant channel 18 from the coolant injection bayonet 31. Turn on the machine tool spindle and transmission screw to perform turning and rolling, and continue processing until the workpiece 16 is processed.

[0066] (4) Turn off the rotation of the machine tool spindle, turn on the machine tool transmission screw to reverse, and return the cutting tool 21 and mounting sleeve 7 to the vicinity of the center 9 to check the machining situation;

[0067] (5) If the processing quality meets the requirements, turn off the pulse power supply and stop injecting coolant;

[0068] (6) Remove workpiece 16, install the next workpiece 16, and repeat the above steps.

[0069] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. An electropulse-assisted cutting-rolling composite surface strengthening device, comprising a machine tool, wherein a chuck mechanism and a tailstock mechanism are respectively provided at the head and tail ends of the machine tool, and a slide box is provided between the chuck mechanism and the tailstock mechanism, characterized in that: It also includes a rolling device and an electrical pulse-assisted turning device; The rolling device includes a fixed base, a mounting sleeve, and rolling components. The fixed base is installed on the upper end of the slide box, and the mounting sleeve is installed on the fixed base. The central axis of the mounting sleeve is collinear with the line connecting the center of the chuck mechanism and the tip of the tailstock mechanism. The mounting sleeve is located on the side of the tool holder away from the chuck mechanism. Multiple rolling components are evenly arranged circumferentially in the inner cavity of the mounting sleeve. The rolling assembly includes a floating base, a rolling base, a guide cylinder, and a rolling end cap connected in sequence. The floating base is fitted into a groove in the inner cavity of the mounting sleeve. A spherical cavity is formed between the guide cylinder and the rolling end cap. A ball bearing is installed in the spherical cavity and protrudes outward from the rolling end cap for rolling the workpiece. The interiors of the floating base, the rolling base, the guide cylinder, and the rolling end cap are interconnected to form a coolant channel. The end face of the rolling end cap is provided with multiple liquid outlet holes. The side wall of the mounting sleeve is provided with liquid guiding channels that correspond one-to-one with and communicate with the coolant channels of each of the rolling assemblies. The coolant is sprayed onto the workpiece rolling part through the liquid outlet holes via the liquid guiding channels and the coolant channels. The electropulse-assisted turning device includes a first brush and a second brush. The first brush is mounted on the machine bed and contacts the chuck mechanism. The second brush is mounted on the fixed base and contacts the workpiece. The first brush and the second brush are respectively connected to the positive and negative terminals of the pulse power supply.

2. The electropulse-assisted cutting-rolling composite surface strengthening device according to claim 1, characterized in that: Both the first brush and the second brush are equipped with magnets, and the first brush and the second brush are magnetically attached to the bed and the fixed base, respectively. The second brush is located between the cutting tool on the tool holder and the mounting sleeve.

3. The electropulse-assisted cutting-rolling composite surface strengthening device according to claim 1, characterized in that: The mounting sleeve includes a mounting assembly, an adjusting sleeve, a limiting ring, and an end cap. The mounting assembly is mounted on the fixed base. The adjusting sleeve is threaded to one end of the mounting assembly, and the end cap is mounted on the other end of the mounting assembly. The end of the mounting assembly near the adjusting sleeve has a T-shaped groove that slides with the floating base. The T-shaped groove is inclined inward from the end near the adjusting sleeve to the end away from the adjusting sleeve. The two ends of the floating base abut against the mounting assembly and the limiting ring, respectively. The limiting ring is slidably disposed coaxially in the inner cavity of the mounting assembly. The limiting ring is located between the floating base and the end cap. A first spring is provided between the limiting ring and the end cap. The two ends of the first spring abut against the limiting ring and the end cap, respectively. Under the elastic force of the first spring, the floating base can be moved along the T-shaped groove by twisting the adjusting sleeve to move closer to or further away from the center of the mounting assembly, thereby adjusting the rolling diameter.

4. The electropulse-assisted cutting-rolling composite surface strengthening device according to claim 3, characterized in that: The floating base has a boss on its end face near the limiting ring. The boss is located in the inner cavity of the limiting ring. When the rolling diameter is at its maximum, the boss abuts against the inner cylindrical surface of the limiting ring.

5. The electropulse-assisted cutting-rolling composite surface strengthening device according to claim 1, characterized in that: The inner cylindrical surface of the guide cylinder is provided with an annular groove, and a sealing ring is installed in the annular groove. The guide cylinder is sealed to the rolling base through the sealing ring. A second spring is provided between the guide cylinder and the rolling base. The two ends of the second spring abut against the inner bottom surface of the guide cylinder and the step on the rolling base, respectively. The guide cylinder and the rolling end cap are connected by threads.

6. The electropulse-assisted cutting-rolling composite surface strengthening device according to claim 1, characterized in that: The outer cylindrical surface of the guide cylinder is provided with scale lines, which are used to display the rolling force in conjunction with the end face of the rolling base.

7. The electropulse-assisted cutting-rolling composite surface strengthening device according to claim 1, characterized in that: Each of the aforementioned liquid guiding channels has a coolant injection bayonet threadedly connected to its outer port.

8. The electropulse-assisted cutting-rolling composite surface strengthening device according to claim 1, characterized in that: The opening at the end of the floating base that is connected to the liquid guiding channel is larger than the port of the liquid guiding channel, so that the floating base is always in communication with the liquid guiding channel during movement; the opening at the end of the floating base that is connected to the rolling base is the same size as the liquid guiding channel.

9. The electropulse-assisted cutting-rolling composite surface strengthening device according to claim 1, characterized in that: The liquid outlet holes are evenly distributed on the end face of the rolling end cover, and the axis of each liquid outlet hole is at an angle to the central axis of the rolling end cover, so that the coolant can be directly sprayed onto the rolling part through the liquid outlet holes.

10. A method for surface strengthening processing using an electrical pulse-assisted cutting-rolling composite method, characterized in that, The electropulse-assisted cutting-rolling composite surface strengthening device according to any one of claims 1 to 9 includes the following steps: (1) The workpiece to be rolled passes through the inner cavity of the mounting sleeve. One end of the workpiece is clamped and fixed by the chuck mechanism, and the other end is positioned by the center. The machine tool is controlled to move the slide box, which drives the cutting tool and the rolling device to move, and moves the cutting tool and the ball to the starting position of the workpiece machining. (2) Adjust the rolling assembly to a suitable position according to process requirements; (3) Turn on the pulse power supply and start injecting coolant from the liquid channel, turn on the machine tool spindle, and perform turning and rolling continuously until the workpiece is finished. (4) Turn off the rotation of the machine tool spindle, retract the cutting tool and the mounting sleeve to the vicinity of the center, and check the machining status; (5) If the processing quality meets the requirements, turn off the pulse power supply and stop injecting coolant; (6) Remove the workpiece, install the next workpiece, and repeat the above steps.

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