Compliant polishing tool and method of making and using same

Abstract

This application relates to the field of magnetic abrasive processing technology, and more particularly to a compliant polishing tool, its preparation method, and its application. The provided compliant polishing tool includes a permanent magnet core and an outer shell layer formed on the surface of the permanent magnet core. The outer shell layer is provided with micropores, and the material of the outer shell layer is selected from elastic materials. This compliant polishing tool can mitigate the impact effect between the tool and the workpiece, prevents severe plastic deformation during polishing, minimizes subsurface damage to the workpiece, and the porous structure of the tool surface can hold the abrasive in the polishing slurry for precise polishing, which is beneficial for its wide application.

Description

Technical Field

[0001] This application belongs to the field of magnetic abrasive processing technology, and particularly relates to an compliant polishing tool, its preparation method and application. Background Technology

[0002] Internal surface polishing is widely used in aerospace, mold making, communications, and automotive industries, such as in aircraft engine pipes, conformal cooling channels, waveguides, and bearing rings. The surface quality of internal surfaces significantly affects the cooling, friction and wear, lubrication, and corrosion resistance of parts. Magnetic abrasive polishing is a common method for internal surface polishing. It utilizes an external magnetic field to harden the magnetic abrasive particles inside the workpiece, forming a soft abrasive head. Material is removed by feeding the workpiece through rotation and the translation of the external magnetic field. The magnetic abrasive powder used is a mixture of micron-sized iron powder and abrasive. Magnetic abrasive polishing is suitable for non-ferromagnetic materials such as stainless steel, aluminum alloys, and ceramics. However, magnetic abrasive polishing typically uses a large external magnetic field, which cannot rotate the workpiece itself. Therefore, the shape of the workpiece is limited to straight tubes or simple bends. Furthermore, the magnetic force between the magnetic abrasive powder and the external magnetic field is relatively weak, resulting in low polishing efficiency, and the distance between the external magnetic field and the workpiece is very small. Additionally, magnetic abrasive powder is expensive and poses an explosion hazard.

[0003] To address the limitations of traditional magnetic abrasive grinding, some researchers have developed Magnetic Driven Internal Surface Polishing (MDIF) technology. This technology utilizes a compact, rotationally symmetric external magnetic field that can rotate and translate, improving controllability and processing flexibility. The workpiece remains stationary, thus its shape is unrestricted, allowing for the creation of irregularly shaped tubes, porous tubes, branched tubes, and spiral tubes. MDIF employs a polishing tool with bonded abrasive coated on a spherical magnet, replacing magnetic abrasive powder, increasing polishing force and improving controllability and efficiency. Furthermore, the small contact area between the spherical tool and the workpiece enables deterministic polishing of the internal surface. MDIF can reduce workpiece surface roughness to 0.1 μm Ra. However, it cannot achieve even lower surface roughness by using smaller abrasive grains, and the rigid impact of the tool on the workpiece surface leads to the formation of a plastic deformation layer, hindering its widespread application. Summary of the Invention

[0004] The purpose of this application is to provide a compliant polishing tool, its preparation method and application, which aims to solve the problem that existing magnetic drive internal surface polishing technology is prone to damage and deformation of workpieces during polishing and is not conducive to obtaining workpieces with higher surface precision.

[0005] To achieve the above-mentioned objectives, the technical solution adopted in this application is as follows:

[0006] In a first aspect, this application provides a compliant polishing tool, which includes a permanent magnet core and an outer shell layer formed on the surface of the permanent magnet core, wherein the outer shell layer is provided with micropores, and the material of the outer shell layer is selected from an elastic material.

[0007] Secondly, this application provides a method for preparing an compliant polishing tool, comprising the following steps:

[0008] Molds with core cavities and outer cavities are provided according to the shape of the conformal polishing tool;

[0009] The permanent magnet core is formed by placing the permanent magnet core in the core mold cavity;

[0010] The elastic material is stirred to form microbubbles, which are then poured into the outer shell cavity and cured. A microporous outer shell layer is formed on the surface of the permanent magnet core, and then demolded to obtain a compliant polishing tool.

[0011] Thirdly, this application provides an application of an compliant polishing tool or a compliant polishing tool prepared by a compliant polishing tool preparation method in the fields of aerospace pipe manufacturing, mold cooling channel manufacturing, communication waveguide manufacturing, and bearing ring manufacturing.

[0012] The first aspect of this application provides a compliant polishing tool, comprising a permanent magnet core and an outer shell layer formed on the surface of the permanent magnet core, wherein the outer shell layer is made of an elastic material. The permanent magnet core provides the driving force required for the tool's rotation. The material with the elastic outer shell exhibits good compliance during polishing by conforming to the curvature changes of the workpiece's inner surface. Furthermore, when the polishing tool impacts the workpiece surface, the elastic outer shell absorbs the tool's kinetic energy, reducing the depth of polishing scratches and the thickness of the plastic deformation layer, thereby improving the workpiece's surface quality. Additionally, if the elastic outer shell wears down after prolonged polishing use, it can be removed and remade, allowing for the continuous use of the permanent magnet core. Moreover, the outer shell layer of the provided tool is provided with micropores. These micropores are designed to combine with abrasive grains in the polishing fluid for polishing, ensuring a tight bond between the abrasive grains and the tool, preventing detachment, and avoiding wear on the outer shell layer, thus significantly extending the lifespan of the compliant polishing tool. Therefore, the provided conformal polishing tool can effectively reduce the impact effect between the tool and the workpiece, and will not cause serious plastic deformation during the polishing process, resulting in less subsurface damage to the workpiece; in addition, the porous structure of the tool surface can hold the abrasive in the polishing slurry for precision polishing, improving the precision of the workpiece and facilitating its widespread use.

[0013] The second aspect of this application provides a method for preparing an compliant polishing tool. This method involves providing a mold with a core cavity and an outer shell cavity according to the shape of the polishing tool, and sequentially setting a permanent magnet core and an elastic outer shell material to prepare the compliant polishing tool. This preparation method is simple, easy to operate, does not require the use of large-scale instruments and equipment, and is conducive to large-scale preparation.

[0014] The conformal polishing tool provided in the third aspect of this application is used in the fields of aerospace pipe manufacturing, mold cooling channel manufacturing, communication waveguide manufacturing, and bearing ring manufacturing. Because the conformal polishing tool can effectively reduce the impact effect between the tool and the workpiece, it can protect the workpiece surface to the maximum extent during the polishing process. At the same time, the tool conforms better and can achieve higher surface quality. It provides a high-precision and flexible polishing tool for polishing in various fields. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the compliant polishing tool provided in the embodiments of this application.

[0017] Figure 2 This is a flowchart illustrating the preparation process of the compliant polishing tool provided in the embodiments of this application.

[0018] Figure 3 This is a schematic diagram of the conformal polishing tool provided in the embodiments of this application polishing a complex inner surface.

[0019] Figure 4 This is a schematic diagram illustrating the polishing implementation of a compliant polishing tool for polishing complex inner surfaces, as provided in the embodiments of this application.

[0020] Figure 5 This is a schematic diagram of the surface roughness of the workpiece before polishing, provided in an embodiment of this application.

[0021] Figure 6 This is a schematic diagram of the surface roughness of the workpiece after polishing, provided in an embodiment of this application. Detailed Implementation

[0022] To make the technical problems, technical solutions, and beneficial effects of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0023] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0024] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b, or c", or "at least one of a, b, and c", can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0025] It should be understood that in the various embodiments of this application, the order of the above processes does not imply the order of execution. Some or all steps may be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0026] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms "a" and "the" as used in the embodiments of this application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0027] The weights of the relevant components mentioned in the embodiments of this application can refer not only to the specific content of each component, but also to the proportional relationship between the weights of the components. Therefore, any scaling up or down of the content of the relevant components according to the embodiments of this application is within the scope disclosed in the embodiments of this application. Specifically, the mass in the embodiments of this application can be a well-known unit of mass in the chemical industry, such as μg, mg, g, or kg.

[0028] The terms "first" and "second" are used for descriptive purposes only, to distinguish objects, such as substances, from one another, and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. For example, without departing from the scope of the embodiments of this application, "first XX" may also be referred to as "second XX," and similarly, "second XX" may also be referred to as "first XX." Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of that feature.

[0029] The first aspect of this application provides a compliant polishing tool, such as... Figure 1 As shown, the compliant polishing tool includes a permanent magnet core 1 and an outer shell layer 2 formed on the surface of the permanent magnet core 1, and the outer shell layer is provided with micropores 3, wherein the material of the outer shell layer 2 is selected from an elastic material.

[0030] The first aspect of this application provides a compliant polishing tool, which includes a permanent magnet core and an outer shell layer formed on the surface of the permanent magnet core. The outer shell layer is made of an elastic material. The permanent magnet core provides the driving force required for the tool's rotation. The material with the elastic outer shell can, on the one hand, adapt to the curvature changes of the workpiece's inner surface during polishing, exhibiting good compliance. Furthermore, when the polishing tool impacts the workpiece surface for polishing, the elastic material outer shell can absorb the tool's kinetic energy, reducing the depth of polishing scratches and the thickness of the plastic deformation layer, thereby improving the quality of the workpiece surface. On the other hand, if the elastic outer shell on the surface of the compliant polishing tool wears after prolonged polishing use, the elastic outer shell can be removed and a new outer shell material can be made, enabling the permanent magnet core to be used continuously. In addition, the outer shell layer of the provided tool is provided with micropores. The micropores are designed to combine with the abrasive grains in the polishing fluid for polishing, making the abrasive grains bond tightly to the tool and preventing them from falling off. At the same time, it does not cause wear to the outer shell layer of the tool, which can significantly improve the life of the compliant polishing tool. Therefore, the provided conformal polishing tool can effectively reduce the impact effect between the tool and the workpiece, and will not cause serious plastic deformation during the polishing process, resulting in less subsurface damage to the workpiece; in addition, the porous structure of the tool surface can hold the abrasive in the polishing slurry for precision polishing, improving the precision of the workpiece and facilitating its widespread use.

[0031] In some embodiments, the provided compliant polishing tool includes a permanent magnet core that provides the necessary driving force for the rotation of the compliant polishing tool, enabling the provided compliant polishing tool to rotate, translate, or remain stationary under the influence of an external magnetic field, which is beneficial for polishing the interior and exterior of workpieces of various shapes.

[0032] In some embodiments, the particle size of the permanent magnet core is 3.5 to 11.5 mm; ensuring that the particle size of the permanent magnet core is appropriate can ensure that the external magnetic field maintains driving force on the tool during use.

[0033] In some specific embodiments, the particle size of the permanent magnet core is selected from, but not limited to, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm, 10mm, 10.5mm, 11mm, and 11.5mm.

[0034] Furthermore, the compliant polishing tool also includes an outer shell layer formed on the surface of the permanent magnet core, wherein the material of the outer shell layer is selected from an elastic material. The material with the elastic outer shell, on the one hand, can conform to the curvature changes of the workpiece's inner surface during the polishing process, exhibiting good compliance. Moreover, when the polishing tool impacts the workpiece surface for polishing, the elastic material shell can absorb the tool's kinetic energy, reducing the depth of polishing scratches and the thickness of the plastic deformation layer, thereby improving the quality of the workpiece surface. On the other hand, if the elastic shell on the surface of the compliant polishing tool wears down after prolonged polishing use, the elastic shell can be removed and remade, enabling the continuous use of the permanent magnet core.

[0035] In some embodiments, the elastic material includes at least one of polydimethylsiloxane, silicone, polyurethane, and rubber.

[0036] In some embodiments, the hardness of the outer shell layer is Shore A hardness of 20 to 80. Controlling the hardness of the outer shell layer to a moderate level ensures stable movement between the compliant polishing tool and the workpiece, which is beneficial for the polishing process. If the hardness of the outer shell layer is too high, it will cause a large impact between the tool and the workpiece surface, resulting in poor surface quality of the processed workpiece; if the hardness of the outer shell layer is too low, the outer shell material will deform excessively, leading to unstable tool movement during polishing and hindering effective polishing.

[0037] In some specific embodiments, the hardness of the outer shell layer includes, but is not limited to, Shore A hardness 20, Shore A hardness 30, Shore A hardness 40, Shore A hardness 50, Shore A hardness 60, Shore A hardness 70, and Shore A hardness 80.

[0038] In some embodiments, the thickness of the outer shell layer is 0.1–2 mm. If the outer shell layer of the polishing tool is too thick, the mass of the polishing tool will increase, its relative magnetism will decrease, and ultimately the driving force of the external magnetic field on it will decrease, making it impossible for the polishing tool to generate stable rotational motion for polishing. If the outer shell layer of the polishing tool is too thin, the overall rigidity of the tool will be too high, and the impact force on the workpiece during polishing will be greater, which is not conducive to obtaining a smooth surface. In addition, the outer shell layer itself will wear down to a certain extent. If it is too thin, the outer shell layer will wear off quickly, leading to tool failure and reduced service life.

[0039] In some specific embodiments, the thickness of the outer shell layer is selected from, but not limited to, 0.1 mm, 0.3 mm, 0.5 mm, 0.7 mm, 1.0 mm, 1.2 mm, 1.5 mm, 1.7 mm, and 2.0 mm.

[0040] Furthermore, the outer shell layer is provided with micropores. Existing magnetic polishing tools use epoxy resin to bond abrasive grains. During the polishing process, the abrasive grains are prone to detachment, leading to a significant decrease in polishing efficiency and a tool life of only 30 minutes. In contrast, the conformal polishing tool provided in this application has a shell layer with micropores. The micropores are designed to combine with the abrasive grains in the polishing slurry for polishing, ensuring a tight bond between the abrasive grains and the tool, eliminating the problem of detachment, and preventing wear on the tool's shell layer. This significantly improves the lifespan of the conformal polishing tool. Moreover, using polishing slurry instead of bonded abrasive grains can produce nanoscale surface roughness, improving the precision of the workpiece surface.

[0041] In some embodiments, the pore size of the micropores is 1–200 μm. The micropores are mainly designed to combine with the abrasive grains in the polishing slurry, allowing the abrasive grains to embed into the micropores on the surface of the outer shell layer. This ensures that the abrasive grains are not easily detached and will not cause wear to the outer shell layer, thus significantly improving the lifespan of the compliant polishing tool.

[0042] In some specific embodiments, the pore size of the micropores is selected from, but not limited to, 1μm, 10μm, 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, 110μm, 120μm, 130μm, 140μm, 150μm, 160μm, 170μm, 180μm, 190μm, and 200μm.

[0043] In some embodiments, the provided compliant polishing tool has a rotationally symmetrical shape. In some embodiments, the rotationally symmetrical shape is selected from at least one of spherical, elliptical, and drum-shaped.

[0044] In some specific embodiments, the compliant polishing tool is selected from spherical shapes. Providing a spherical compliant polishing tool allows it to conform to workpiece surfaces with different radii of curvature, facilitating its use on workpieces of various shapes. Driven by a rotating external magnetic field, the tool can rotate at high speed and stably at a specific location on the inner surface of the workpiece. By adding polishing fluid, precision polishing of the inner surface of the workpiece can be achieved. The external magnetic field can be driven by a six-axis robot or machining center to achieve rotational and translational movements; the workpiece can be an irregularly shaped tube, a porous tube, a branched tube, or a spiral tube.

[0045] In some embodiments, the diameter of the spherical compliant polishing tool is 4–12 mm. If the diameter of the spherical compliant polishing tool is too small, the magnetism of the polishing tool will decrease, making it unable to be controlled by an external magnetic field to generate rotational motion, thus affecting the polishing process. If the diameter of the polishing tool is too large, the tool cannot generate stable rotational motion under the action of an external magnetic field, making it unsuitable for internal hole polishing and detrimental to its use. In some specific embodiments, the diameter of the spherical compliant polishing tool is selected from, but not limited to, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5 mm, 10 mm, 10.5 mm, 11 mm, 11.5 mm, and 12 mm.

[0046] The second aspect of this application provides a method for preparing an compliant polishing tool, such as... Figure 2 As shown, it includes the following steps:

[0047] S01. Provide a mold with a core cavity and a shell cavity according to the shape of the conformal polishing tool;

[0048] S02. The permanent magnet core is placed in the core mold cavity to form the permanent magnet core;

[0049] S03. The elastic material is stirred to form microbubbles, then poured into the outer shell mold cavity and cured. A microporous outer shell layer is formed on the surface of the permanent magnet core. Then, the mold is demolded to obtain a compliant polishing tool.

[0050] The second aspect of this application provides a method for preparing an compliant polishing tool. This method provides a mold with a core cavity and an outer shell cavity according to the shape of the polishing tool, and sequentially sets a permanent magnet core and an elastic outer shell material to prepare the compliant polishing tool. This preparation method is simple, easy to operate, does not require the use of large instruments and equipment, and is conducive to large-scale preparation.

[0051] In step S01, a mold having a core cavity and a shell cavity is provided according to the shape of the conformal polishing tool.

[0052] In some embodiments, the provided mold includes an upper mold and a lower mold, and both the upper mold and the lower mold include a core cavity and a shell cavity; and the top of the upper mold has a gate for pouring liquid shell material, and the lower mold is designed with a columnar support structure to ensure that the spherical magnet is in the center of the cavity in the vertical direction.

[0053] In some embodiments, the provided mold may be prepared by CNC milling or 3D printing.

[0054] In some embodiments, the mold material is selected from any one of aluminum alloy, steel, and plastic.

[0055] In step S02, the permanent magnet core is placed in the core mold cavity to form the permanent magnet core.

[0056] In some embodiments, a spherical magnet is placed in a bottom mold, and then the mold is closed. During the mold closing process, four horizontal support structures are used to position the spherical magnet at the center of the inner cavity to ensure the uniformity of the shell structure and form a permanent magnet core.

[0057] In step S03, the elastic material is stirred to form microbubbles, then poured into the outer shell mold cavity and cured. A microporous outer shell layer is formed on the surface of the permanent magnet core, and then demolded to obtain a compliant polishing tool.

[0058] In some embodiments, the step of stirring the elastic material to form microbubbles includes: forming microbubbles by mixing air into liquid PDMS and stirring, and these microbubbles solidifying to form a microporous structure.

[0059] In some embodiments, a liquid elastic material containing microbubbles is cast into the outer shell mold cavity and cured, wherein the curing temperature is 60–75°C and the time is 40–60 minutes. Through the curing process, a microporous outer shell layer is formed on the surface of the permanent magnet core.

[0060] In some specific embodiments, the curing temperature is selected from, but not limited to, 60°C, 62°C, 65°C, 67°C, 70°C, 72°C, and 75°C. The curing time is selected from, but not limited to, 40 minutes, 42 minutes, 45 minutes, 47 minutes, 50 minutes, 52 minutes, 55 minutes, 57 minutes, and 60 minutes.

[0061] In some embodiments, a demolding process is performed to remove the tool from the mold and trim it to remove excess material at the gate, resulting in a conformable polishing tool.

[0062] In some specific embodiments, the elastic material is selected as polydimethylsiloxane, and the specific preparation method includes: mixing polydimethylsiloxane and curing agent at a mass ratio of 10:1, stirring evenly, and curing in an oven at 75°C for 60 minutes to obtain an outer shell material with a Shore A hardness of 40.

[0063] The third aspect of this application provides an application of an compliant polishing tool, or a compliant polishing tool prepared by the provided method, in the fields of aerospace pipe manufacturing, mold cooling channel manufacturing, communication waveguide manufacturing, and bearing ring manufacturing.

[0064] The compliant polishing tool provided in the third aspect of this application is used in the fields of aerospace pipe manufacturing, mold cooling channel manufacturing, communication waveguide manufacturing, and bearing ring manufacturing. Because the compliant polishing tool can effectively reduce the impact effect between the tool and the workpiece, it can protect the workpiece surface to the maximum extent during the polishing process. At the same time, the tool has better compliance and can achieve higher surface quality. It provides a high-precision and flexible polishing tool for polishing in various fields.

[0065] In some embodiments, the compliant tooling exhibits good compliance, enabling MDIF to be used for polishing a variety of complex internal surfaces, such as... Figure 3 As shown, the tubes include shaped tubes (a), porous tubes (b), branched tubes (c), and spiral tubes (d); for porous tubes, each hole needs to be polished separately; when polishing spiral tubes, the workpiece needs to be rotated to eliminate interference at certain positions.

[0066] In some specific embodiments, the compliant polishing tool is used for polishing, such as... Figure 4 As shown, a robot 4 is provided, including a robot base 44, a robot end effector 41, one end of a spindle 42 connected to the robot end effector 41, and a rotationally symmetrical external magnetic field 5 installed on the robot end effector 41, driven to rotate by the spindle 42; the robot 4 can provide complex paths through a control program. A workpiece 7 is mounted on a worktable 8 via a fixture 91; a compliant polishing tool 6 is placed inside the workpiece 7 and can move along the path 61 of the external magnetic field; during polishing, the micropores on the surface of the compliant tool 3 hold the abrasive grains in the polishing fluid 8 for polishing.

[0067] The following description is based on specific embodiments.

[0068] Example 1

[0069] Compliant Polishing Tools, Their Preparation and Application

[0070] Compliant polishing tools

[0071] The compliant polishing tool is a spherical compliant polishing tool, including a permanent magnet core and an outer shell layer formed on the surface of the permanent magnet core. The outer shell layer is provided with micropores. The material of the outer shell layer is selected from polydimethylsiloxane, an elastic material with a Shore A hardness of 40. The particle size of the permanent magnet core is 8 mm, the thickness of the outer shell layer is 1 mm, and the pore size of the micropores is 10 μm.

[0072] A method for preparing a conforming polishing tool includes the following steps:

[0073] Based on the shape of the conformal polishing tool, a mold with a core cavity and an outer cavity is provided by CNC milling. The mold includes an upper mold and a lower mold, and both the upper mold and the lower mold include a core cavity and an outer cavity. Furthermore, the top of the upper mold has a gate for pouring liquid outer shell material, and the lower mold is designed with a columnar support structure to ensure that the spherical magnet is in the center of the cavity in the vertical direction.

[0074] The spherical magnet is placed in the bottom mold, and then the mold is closed. During the mold closing process, four horizontal support structures are used to keep the spherical magnet in the center of the inner cavity to ensure the uniformity of the shell structure and form a permanent magnet core;

[0075] Polydimethylsiloxane and curing agent were mixed at a mass ratio of 10:1 and stirred evenly. Air was mixed into liquid PDMS and stirred to form micro bubbles. The mixture was then placed in an oven at 75°C and cured for 60 minutes to obtain an outer shell material with a Shore A hardness of about 40.

[0076] Remove the tool from the mold and trim it to remove excess material from the gate, resulting in a conforming polishing tool.

[0077] Polishing is performed using this conformal polishing tool.

[0078] Specifically, such as Figure 4 As shown, a robot 4 is provided, including a robot base 44, a robot end effector 41, one end of a spindle 42 connected to the robot end effector 41, and a rotationally symmetrical external magnetic field 5 installed on the robot end effector 41, driven to rotate by the spindle 42; the robot 4 can provide complex paths through a control program. A workpiece 7 is mounted on a worktable 8 via a fixture 91; a compliant polishing tool 6 is placed inside the workpiece 7 and can move along the path 61 of the external magnetic field; during polishing, the micropores on the surface of the compliant tool 3 hold the abrasive grains in the polishing fluid 8 for polishing.

[0079] During the polishing process, the following conditions are controlled: the diameter of the polishing tool is controlled to be 10 mm, the inner diameter of the polishing tool is 15 mm, and the outer diameter of the polishing tool is 19 mm. In addition, an Al2O3 polishing slurry with an average particle size of 1 μm and a mass percentage concentration of 30 wt% is provided. The external magnetic field speed is controlled to be 1400 rpm, and the polishing time is 10 minutes.

[0080] Performance testing and results analysis

[0081] In Example 1, the surface roughness profile of the workpiece before polishing is shown in the figure. Figure 5 The surface roughness profile of the workpiece after polishing is shown in the figure. Figure 6 .Depend on Figure 5 and Figure 6The comparison shows that after polishing the inner surface of the workpiece with the polishing tool provided in this application, the surface roughness Ra decreased from the initial 0.393±0.045μm to 0.033±0.004μm, the surface quality was improved by 91%, and the workpiece surface was close to a mirror surface.

[0082] In summary, the provided compliant polishing tool includes a permanent magnet core and an outer shell layer formed on the surface of the permanent magnet core, with the outer shell layer made of an elastic material. The permanent magnet core provides the driving force required for tool rotation. The material with the elastic outer shell exhibits good compliance during polishing, adapting to the curvature changes of the workpiece's inner surface. Furthermore, when the polishing tool impacts the workpiece surface, the elastic outer shell absorbs the tool's kinetic energy, reducing the depth of polishing scratches and the thickness of the plastic deformation layer, thereby improving the workpiece surface quality. Additionally, if the elastic outer shell wears down after prolonged polishing use, it can be removed and remade, allowing for continuous use of the permanent magnet core. Moreover, the outer shell layer of the provided tool is provided with micropores. These micropores are designed to combine with abrasive grains in the polishing fluid for polishing, ensuring a tight bond between the abrasive grains and the tool, preventing detachment, and avoiding wear on the outer shell layer, thus significantly extending the lifespan of the compliant polishing tool. Therefore, the provided conformal polishing tool can effectively reduce the impact effect between the tool and the workpiece, and will not cause serious plastic deformation during the polishing process, resulting in less subsurface damage to the workpiece; in addition, the porous structure of the tool surface can hold the abrasive in the polishing slurry for precision polishing, improving the precision of the workpiece and facilitating its widespread use.

[0083] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A conformal polishing tool, characterized in that, The compliant polishing tool includes a permanent magnet core and an outer shell layer formed on the surface of the permanent magnet core. The outer shell layer is provided with micropores. The material of the outer shell layer is selected from an elastic material. The outer shell layer is formed by stirring the elastic material to form microbubbles and then pouring and solidifying it.

2. The compliant polishing tool according to claim 1, characterized in that, The elastic material includes at least one of polydimethylsiloxane, silicone, polyurethane, and rubber.

3. The compliant polishing tool according to claim 1, characterized in that, The hardness of the outer shell layer is Shore A hardness of 20~80.

4. The compliant polishing tool according to claim 1, characterized in that, The compliant polishing tool has a rotationally symmetrical shape.

5. The compliant polishing tool according to claim 4, characterized in that, The rotationally symmetrical shape is selected from at least one of spherical, elliptical, and drum-shaped.

6. The compliant polishing tool according to any one of claims 1-4, characterized in that, The permanent magnet core has a particle size of 3.5~11.5 mm; and / or, The thickness of the outer shell layer is 0.1~2 mm.

7. The compliant polishing tool according to any one of claims 1-4, characterized in that, The pore size of the micropores is 1~200 μm.

8. A method for preparing a compliant polishing tool as described in any one of claims 1-7, characterized in that, Includes the following steps: A mold having a core cavity and a shell cavity is provided according to the shape of the compliant polishing tool; A permanent magnet core is formed by placing the permanent magnet core in the core cavity; The elastic material is stirred to form microbubbles, which are then poured into the outer shell cavity and cured. A shell layer with micropores is formed on the surface of the permanent magnet core. After demolding, a compliant polishing tool is obtained.

9. The method for preparing the compliant polishing tool according to claim 8, characterized in that, The curing process is carried out at a temperature of 60-75°C for 40-60 minutes.

10. The application of a compliant polishing tool as described in any one of claims 1-7 or a compliant polishing tool prepared by the preparation method of the compliant polishing tool provided in claim 8 or 9 in the fields of aerospace pipe manufacturing, mold cooling channel manufacturing, communication waveguide manufacturing, and bearing ring manufacturing.

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