CN100999061A - Grinding polishing method based on magnetic rheology effect and its polishing device - Google Patents

Abstract

The invention discloses a grinding and polishing method based on the magnetorheological effect. Free abrasives are added to the magnetorheological fluid as a grinding and polishing fluid and injected between a magnetic body and the surface of a workpiece. The particles are arranged in series to wrap and constrain the abrasive particles on the end surface of the magnetic body to form a magnetic grinding brush, which constitutes a grinding tool, and performs grinding and polishing on the surface of the workpiece; the invention also discloses the grinding and polishing method based on the magnetorheological effect. The polishing device consists of a grinding tool installed on the main shaft connected to the motor and a workbench for installing the workpiece. The grinding tool is composed of several small-sized magnetic bodies arranged and combined into a flat or curved grinding surface. The grinding and polishing liquid composed of liquid and free abrasives constitutes a lattice magneto-rheological effect grinding brush, and the magnetic body is made of permanent magnets or electromagnets; this device can achieve the effect of high-efficiency and high-precision grinding and processing of ultra-smooth surfaces.

Description

Grinding and polishing method and polishing device based on magnetorheological effect

technical field

The invention relates to plane and curved surface grinding and processing methods, in particular to a grinding and polishing method based on the magneto-rheological effect. The present invention also relates to a device used in the magneto-rheological effect grinding and polishing method.

Background technique

With the electronicization of information and the high-speed and large-capacity of photoelectric signal transmission, the demand for optoelectronic products that integrate electronic technology and optical technology is increasing, such as CD/DVD optical reading head, optical/electrical (PD) in optical fiber communication And electrical/optical (LD) signal converters, projectors, laser printers, molecular lasers, etc., one of the core components of optoelectronic products is the optical components (lenses, mirrors) used in the optical path, and the manufacturing methods of optical components mainly include ceramics Single-piece small-batch mechanical processing of hard and brittle materials such as optical glass and industrial mass-production molding of heat-plastic materials such as plastic and glass. The surface of optical elements and the surface of hot-pressing molds need to be mechanically processed Shape accuracy and surface accuracy requirements. In order to achieve good optical performance of optical components, the surface precision needs to be ultra-smooth, and the surface shape precision also has high requirements. The processing methods of optical surfaces mainly include diamond tool cutting, grinding, grinding and polishing and their combination. Grinding and polishing is an effective processing method to finally obtain an ultra-smooth surface.

There are more and more applications of ultra-smooth planes, such as the surface of optical disc molds, the surface of single crystal silicon wafers, etc., and finally need to be ground and polished to achieve the required shape accuracy and surface roughness. More and more hard and brittle materials such as optical glass, engineering ceramics, ultra-fine cemented carbide, and stainless steel are used for parts with ultra-smooth surface requirements.

Grinding process is to use a soft grinding disc and a grinding liquid (a mixture of oil or water-based substances and free abrasives), apply a certain pressure to the free abrasive through the grinding disc to act on the surface of the workpiece, and the abrasive rolls or slides on the interface between the grinding disc and the workpiece. Remove a very thin layer of material from the surface of the workpiece to achieve the purpose of improving the shape accuracy and surface accuracy of the workpiece.

Existing grinding and polishing devices are mainly composed of a grinding disc installed on a main shaft connected to a motor and a rotary table connected to a motor for installing workpieces. When working, the workpiece is installed on the workbench, and a certain motion relationship is maintained between the grinding disc and the workpiece. The grinding disc exerts a certain pressure on the free abrasive to achieve grinding and polishing on the surface of the workpiece.

The grinding method is to embed abrasives on the surface of a rigid grinding tool (cast iron, tin, etc.), and under a certain pressure, through the relative movement between the grinding tool and the workpiece, remove a small amount of the surface of the workpiece to obtain high precision and low surface. The process method of roughness. Existing grinding and polishing methods mainly contain (1) the grinding disc substrate is made of metal material, and free abrasives are added to the mechanical grinding and polishing between the grinding disc and the workpiece, such as cast iron grinding discs plus abrasive/grinding paste; (2) A polishing pad is used between the grinding disc and the workpiece, and the polishing pad produces the effect of applying polishing pressure and restraining free abrasives; (3) mechanochemical grinding and polishing that increases chemical/electrochemical action in the mechanical grinding process, (4) curved surface Scanning grinding and polishing of small-sized tools; (5) Equal grinding and polishing of airbags, all of which belong to free abrasive processing.

The existing problems in the grinding and polishing process of free abrasives are: the speed, trajectory, and residence time of free abrasive particles between the grinding disc and the workpiece cannot be effectively controlled, and the free abrasive between the grinding disc and the workpiece interface is only relatively small. The large-sized abrasive particles produce processing effect, and due to the relative motion, a considerable part of the smaller-sized abrasive particles has not interfered with the surface of the workpiece, that is, they are separated from the interface between the grinding disc and the workpiece, resulting in low processing accuracy and efficiency. For grinding and polishing, which uses free abrasives for processing, the key to improving the processing efficiency and processing accuracy of free abrasives is how to ensure a uniform abrasive concentration distribution on the contact interface between the grinding disc and the workpiece, and how to maintain this state stably for a long time , the existing mechanical and chemical grinding methods are difficult to achieve this, thus affecting the precision and efficiency of ultra-smooth surface grinding.

Contents of the invention

The object of the present invention is to solve the problems existing in the existing ultra-smooth surface grinding technology, and to provide a grinding method using the magnetorheological effect, using a mixture of magnetorheological fluid and free abrasive as the grinding and polishing fluid, and using a magnetic substance As the base of the grinding tool, the magnetorheological effect of bonding and solidifying the magnetorheological fluid under the action of a magnetic field is used to constrain and gather free abrasives on the top of the base of the grinding tool to form a magnetorheological effect grinding brush. Small-sized magnetic bodies are arranged and combined into a flat or curved surface structure, and the magneto-rheological effect grinding brushes on the end faces form a lattice cluster grinding tool, so that free abrasives are confined in each micro-sized magneto-rheological effect grinding brush, ensuring The concentration and stability of abrasive particles between the grinding tool and the surface of the workpiece, due to the magneto-rheological effect of the lattice cluster distribution in the grinding tool, the grinding brush has a certain hardness to generate polishing pressure on the surface of the workpiece, and the abrasive particles produce grinding processing on the surface of the workpiece The grinding effect of the magneto-rheological effect grinding brush is inversely proportional to the gap between the grinding tool and the surface of the workpiece. Due to the precise geometric relationship between the grinding tool and the surface of the workpiece, the surface shape can be corrected, and the convex surface of the workpiece Points have a higher material removal rate and pits have a lower material removal rate, so high-efficiency and high-precision grinding and polishing can achieve the effect of ultra-smooth surface.

The purpose of the present invention is also to provide a device used in the magneto-rheological effect grinding method.

The technical scheme of the grinding and polishing method based on the magnetorheological effect provided by the present invention is to add free abrasives into the magnetorheological fluid as a grinding and polishing fluid and inject it between the magnetic body and the surface of the workpiece. The particles are arranged in series to wrap and constrain the abrasive particles on the end surface of the magnetic body to form a magnetic grinding brush and a grinding tool to grind and polish the surface of the workpiece.

The above-mentioned magnetorheological fluid can be selected from the existing commercial magnetorheological fluid, or the following magnetorheological fluid composed of its parts by weight: 50-60% by weight of silicone oil, 30-40% by weight of solid dispersed particles, The weight percentage of oleic acid is 2-3%, and the weight percentage of abrasive material is 3-15%.

The solid dispersed particles of the self-made magnetorheological fluid are mainly ferromagnetic substances, including carbonyl iron powder and reduced iron powder.

The free abrasives added to the magnetorheological fluid include silicon carbide (SiC), diamond, cubic nitride (CBN), aluminum oxide (Al ₂ O ₃ ), silicon nitride (Si ₃ N ₄ ), zirconia One or more mixtures of (ZrO ₂ ), the abrasive particle diameter is less than 20 microns, and the weight percentage of free abrasive and magnetorheological fluid is less than 15%.

The above-mentioned magnetic body can be a permanent magnet or an electromagnet, and the magnetic body can be a grinding and polishing tool composed of a plurality of magnetic rods arranged in a lattice, or a grinding and polishing tool composed of a distributed magnetic field.

The above-mentioned workpiece material can be non-metal hard and brittle materials such as ceramics and glass, and can also be metal materials such as non-magnetic stainless steel.

The technical scheme of a magneto-rheological effect grinding plane polishing device provided by the present invention is that the workpiece 2-1 with a flat processing surface is installed on the rotary table 5, the rotary table 5 is connected with the rotary table spindle 6, and the rotary table spindle 6 is connected with the rotary table spindle motor and the transmission mechanism 7; the grinding tool X-direction feed system 13 and the grinding tool Z-direction feed system 14 are installed on the body frame 8 and connected with the machine tool grinding disc spindle 10, the grinding tool spindle The motor 12 is connected with the grinding tool main shaft transmission mechanism 11, the machine tool grinding disc main shaft 10 is connected with the grinding tool main shaft transmission mechanism 11 and installed on the fuselage stand 8, the above-mentioned machine tool grinding disc main shaft 10 is equipped with a grinding tool, and the grinding and polishing liquid nozzle 15 Add the grinding and polishing fluid 3 between the grinding tool and the workpiece. The above-mentioned grinding and polishing liquid 3 is a mixed liquid of magnetorheological fluid and abrasive, and the free abrasive particles 3-2 in the above-mentioned grinding and polishing liquid are wrapped and constrained by the chains of ferromagnetic particles 3-1 in the magnetorheological liquid to form a magnetorheological Effect grinding brush4.

The above-mentioned grinding tool is a dot-matrix magnetic plane grinding tool 1-1, and another distributed magnetic plane grinding tool 1-2 can be selected.

The above-mentioned dot-matrix magnetic plane grinding tool 1-1 is distributed with a number of fine rod-shaped magnetic bodies to form an array of magnetorheological effect grinding brushes 4, and the matrix of the above-mentioned dot-matrix magnetic plane grinding tool 1-1 is made of non-magnetic material The magnetic body in the shape of a fine rod column is selected from the unit permanent magnet cylinder 1-1-1 or the unit ferromagnetic cylinder 1-1-2, and the unit ferromagnetic cylinder 1-1-2 surrounds the electromagnetic coil 1-1- 4 Connect the DC power supply 1-1-3 and connect it with the conductive copper ring slider assembly 9.

The above-mentioned distributed magnetic planar grinding tool 1-2 is made of ferromagnetic materials, and the magnetic body 1-2-1 of the distributed magnetic planar grinding tool is divided into a ring structure by a copper dividing strip 1-1-3 to form a distributed magnetic field. The magnetic gasket 1-2-3 is installed between the magnetic body 1-2-1 of the distributed magnetic plane grinding tool and the substrate of the distributed magnetic plane grinding tool, and the base body of the distributed magnetic plane grinding tool is embedded with an electromagnetic coil or a permanent magnetic ferrule 1- 2-4, The substrate of the distributed magnetic plane grinding tool is made of non-magnetic material.

The above-mentioned workbench adopts a rotary workbench or a workbench controlled by numerical control interpolation motion.

The grinding end face of the above-mentioned grinding tool has a planar shape macroscopically as a whole.

The grinding tool itself may or may not rotate.

The above-mentioned workpiece material can be hard and brittle materials such as optical glass, cemented carbide, engineering ceramics, or non-magnetic materials such as stainless steel.

Another technical solution of the magneto-rheological effect grinding curved surface polishing device provided by the present invention is that the workpiece is installed on the workbench 5, and the X-direction feed system 13 and the Y-direction feed system 16 are respectively connected to the workbench 5 and the numerical control system 17. Numerical control system 17 is connected with computer 18; Z feed system 14 is installed on the fuselage stand 8 and is connected with numerical control system 17, and the grinding tool spindle motor 12 is installed at the lower end of fuselage stand 8, and above-mentioned grinding tool spindle motor 12 is equipped with a grinding tool, inject the grinding and polishing liquid 3 between the grinding tool and the workpiece through the grinding and polishing liquid nozzle 15. The above-mentioned grinding and polishing liquid 3 is a mixed liquid of magnetorheological fluid and abrasive, and the free abrasive particles 3-2 in the above-mentioned grinding and polishing liquid are wrapped and constrained by the chains of ferromagnetic particles 3-1 in the magnetorheological liquid to form a magnetorheological Effect grinding brush4.

The above-mentioned grinding tool is a combined magnetic curved surface grinding tool. The above-mentioned grinding tools can also be selected from distributed magnetic curved surface grinding tools.

The above-mentioned grinding tool selects a combined magnetic curved surface grinding tool, which is composed of a magnetic curved surface grinding tool substrate 1-3-1 and a permanent magnet 1-3-2 with an arc section to form a magneto-rheological effect grinding brush with an arc section; the above-mentioned several The permanent magnet 1-3-2 with circular arc section is installed around the base body 1-3-1 of the magnetic curved surface grinding tool, and the base body 1-3-1 of the magnetic curved surface grinding tool is made of non-magnetic material.

The above-mentioned distributed magnetic curved surface grinding tool is composed of a magnetic curved surface grinding tool substrate 1-3-1, an electromagnetic coil or a permanent magnetic ferrule 1-3-3, a magnetic isolation washer 1-3-4, a copper dividing strip 1-3-5 and Distributed magnetic body 1-3-6 with arc cross-section shape; magnetic surface grinding tool substrate 1-3-1 is made of non-magnetic material, and distributed magnetic body 1-3-6 with arc cross-section shape is made of ferromagnetic material It is made of 1-3-5 copper partition belt to form a distributed magnetic field and a magneto-rheological effect grinding belt with a circular arc section. The electromagnetic coil or permanent magnetic ferrule 1-3-3 is embedded in the magnetic surface grinding tool base 1- In 3-1, the magnetic isolation washer 1-3-4 is installed between the magnetic curved surface grinding tool base 1-3-1 and the electromagnetic coil or permanent magnetic ferrule 1-3-3.

The grinding end surface of the above-mentioned grinding tool is generally in the shape of a circular arc cross-section macroscopically, and can be rotated or not rotated.

The aforementioned workpiece is the workpiece 2-2 with an axisymmetric curved surface or the workpiece 2-3 with a non-axisymmetric curved surface.

The above-mentioned workbench 5 is a rectangular mobile workbench or a rotary workbench.

The above-mentioned workpiece is a concave curved surface or a convex curved surface or a curved surface with a combination of convex and concave.

The above-mentioned workpiece material can be hard and brittle materials such as optical glass, cemented carbide, engineering ceramics, or non-magnetic materials such as stainless steel.

Magnetorheological fluid is a general term for functional liquid materials whose viscosity can be controlled by the strength of a magnetic field. In magnetorheological fluid, ferromagnetic particles are arranged in series under the action of a magnetic field, which manifests as an increase in apparent viscosity, making the liquid unable to resist shear The phenomenon of producing yield stress with obvious yield effect is the magnetorheological effect.

The magnetorheological effect grinding and polishing processing method of the present invention is to add a mixture of free abrasives to the magnetorheological fluid as a grinding and polishing fluid and place it between the grinding tool made of magnetic bodies and the workpiece, and arrange the small-sized magnetic bodies in a certain order Combined, under the action of a magnetic field, the top of the small-sized magnetic body forms a cluster of lattice-type magneto-rheological effect grinding brushes to form a grinding tool, which can perform ultra-smooth grinding and polishing on flat and curved surfaces.

The magneto-rheological effect grinding and polishing device of the present invention is composed of a grinding tool installed on the main shaft connected to the motor and a workbench for installing workpieces. It is characterized in that the grinding tools are arranged and combined into a plane or The curved surface grinding working surface forms a lattice type magneto-rheological effect grinding brush in the grinding and polishing liquid composed of magnetorheological fluid and free abrasive, and the magnetic body is made of permanent magnet or electromagnet.

In order to generate a magnetic field to achieve the effect of gathering and confining free abrasive particles, the surface of the grinding tool base has magnetic bodies distributed in arrays or continuously.

In order to realize the grinding process of the plane, the working surface of the grinding tool is macroscopically plane as a whole. In order to realize the grinding process of the free-form surface, the grinding working surface of the grinding tool is generally in the shape of an arc-shaped surface of revolution macroscopically.

The working principle of the present invention is: mix the free fine abrasives into the magnetorheological fluid, utilize the magnetorheological effect that the ferromagnetic particles are distributed in chains and the viscosity increases under the action of the magnetorheological fluid under the action of a magnetic field, and the free abrasive particles are absorbed by the magnetorheological fluid The ferromagnetic particle chains in it are wrapped and constrained together to form a magneto-rheological effect grinding brush. When the tool base is made of permanent magnets or electromagnets, radial magnetic force lines are formed at the top of the magnetic poles. Since the ferromagnetic particles are arranged along the magnetic force lines, agglomeration occurs. The enrichment band at the top of the magnetic pole constitutes the magnetorheological effect grinding brush. When the grinding tool substrate is made with lattice distributed magnetic poles or continuous distributed magnetic poles, an organized lattice magnetorheological effect will be formed on the surface of the grinding tool. Abrasive brushes or magneto-rheological effect grinding belts, when the grinding tool and the workpiece move relative to each other, the magneto-rheological effect grinding brushes or magnetorheological effect grinding belts form complex motion tracks on the surface of the workpiece and produce micro-cutting effects, which can Grinding is performed on the surface of the workpiece to improve its shape accuracy and reduce its surface roughness to an ultra-smooth level.

The fundamental difference between the present invention and the existing grinding processing technology is as follows: 1) the surface of the grinding tool of the present invention has magnetic bodies with array distribution or continuous distribution to generate a magnetic field; Magneto-rheological effect grinding brushes, or continuously distributed magnetorheological effect grinding belts instead of single-layer, single free abrasives, reduce the impact of the size inhomogeneity of free abrasives on processing accuracy and efficiency; 3) abrasive particles of the present invention The micro-cutting force on the surface of the workpiece is the combined effect of the positive pressure and shear force generated by the magneto-rheological effect grinding brush or the magneto-rheological effect grinding belt. The magneto-rheological effect grinding brush or the magneto-rheological effect grinding belt itself has elasticity , the process of acting on the processed surface is uniform, gentle and controllable, rather than the mechanical action applied to the free abrasive through the grinding tool substrate, or the mechanical action between the grinding disc and the workpiece in mechanical grinding, which is conducive to obtaining an ultra-smooth surface; 4) Magnetic The rheological effect abrasive brush or magnetorheological effect abrasive belt has different rigidity and holding strength for abrasive particles at different parts due to different magnetic field strengths. At the same time, the abrasive particles in the magnetorheological effect abrasive brush or magnetorheological effect abrasive belt The concentration can be controlled, which is beneficial to the control of processing efficiency and processing accuracy during the grinding process; 5) The grinding effect of the magneto-rheological effect grinding brush is inversely proportional to the gap between the grinding tool and the surface of the workpiece, and the bumps on the surface of the workpiece have a higher The material removal rate of the pit has a low material removal rate, which can achieve the effect of high-efficiency and high-precision grinding and polishing for ultra-smooth surfaces.

Beneficial effects of the present invention: the arrayed magneto-rheological effect grinding brushes or continuous magneto-rheological effect grinding belts formed on the surface of the grinding tool produce free abrasive particles that are uniformly and stably distributed on the surface of the grinding tool and act on the workpiece processing surface, It solves the problem that the free abrasive can not be evenly distributed on the workpiece interface in the existing grinding technology, the abrasive concentration is difficult to maintain, and the abrasive size is uneven, which affects the grinding accuracy and efficiency. The strength of the magnetic field determines the magnetorheological effect of the grinding brush or the continuous magnetorheological effect. The bonding strength of the abrasive particles in the grinding belt, the processing characteristics are between the fixed abrasive and the free abrasive, on the one hand, it can always maintain the concentration and uniformity of the free abrasive on the workpiece processing interface, and at the same time, the magnetorheological effect is soft to the free abrasive particles. Constraints, centrifugal force and micro-cutting force may cause abrasive particles to break free and become blunt. When subjected to excessive cutting force, the magnetorheological fluid close to solid state will yield and flow and abrasive particles will escape. The self-renewal mechanism of abrasive particles during processing Make the blunt abrasive grains fall off continuously, increase the flow of abrasive grains, and improve the material removal effect. At the same time, there is no need to consider the tool wear problem that plagues the general processing process. On the other hand, the magnetorheological effect grinding brush or the continuous magnetorheological effect grinding belt itself has viscoelasticity and plays the role of a polishing pad. During the grinding process, it will not damage the processed surface of the workpiece like a consolidated abrasive tool, and achieve high precision. For grinding purposes.

Description of drawings

Fig. 1 is the working principle figure of magneto-rheological effect grinding processing method of the present invention;

Fig. 2 is the schematic diagram of the present invention applying the magneto-rheological effect grinding method to carry out plane processing;

Fig. 3 is a schematic diagram of the present invention applying the magnetorheological effect grinding method to process an axisymmetric surface of revolution;

Fig. 4 is the schematic diagram of the non-axisymmetric curved surface processing by applying the magnetorheological effect grinding method in the present invention;

Fig. 5 is the structure schematic diagram of the dot-matrix magnetic planar grinding tool that the present invention uses;

Fig. 6 is the magnetic structure schematic diagram of the dot-matrix magnetic planar grinding tool used in the present invention;

Fig. 7 is a schematic structural view of the distributed magnetic planar grinding tool used in the present invention;

Fig. 8 is a structural schematic diagram of a dot matrix magnetic curved surface grinding tool used in the present invention;

Fig. 9 is a schematic structural diagram of a distributed magnetic curved surface grinding tool used in the present invention;

Fig. 10 is a schematic structural view of the device used for plane grinding according to the method of the present invention;

Fig. 11 is a schematic structural view of the device used for grinding and processing curved surfaces according to the method of the present invention;

The meaning of each number in the figure: 1. Magnetic body, 1-1. Dot matrix magnetic flat grinding tool, 1-2. Distributed magnetic flat grinding tool, 1-1-1. Unit permanent magnet cylinder, 1-1- 2. Unit ferromagnetic cylinder, 1-1-3. DC power supply, 1-1-4. Electromagnetic coil, 1-2-1. Distributed magnetic plane grinding tool magnetic body, 1-2-2. Copper partition belt , 1-2-3. Magnetic isolation washer, 1-2-4. Electromagnetic coil or permanent magnet ferrule, 1-3. Surface magnetic grinding tool, 1-3-1. Dot matrix magnetic surface grinding tool substrate, 1 -3-2. Permanent magnet with circular arc section, 1-3-3. Electromagnetic coil or permanent magnet ferrule, 1-3-4. Magnetic isolation washer, 1-3-5. Copper dividing strip, 1-3-6 Distributed magnetic body with circular arc cross-section shape, 2. Processing surface, 2-1. The processing surface is a flat workpiece, 2-2. The processing surface is an axisymmetric surface of revolution, 2-3. The processing surface is a non-axisymmetric surface 3. Grinding and polishing fluid (magnetorheological fluid and abrasive mixture), 3-1. Ferromagnetic particles, 3-2. Abrasive particles, 4. Magnetorheological effect grinding brush, 5. Workbench, 6. Rotary table spindle, 7. Rotary table spindle motor and transmission mechanism, 8. Fuselage stand, 9. Conductive copper ring slider assembly, 10. Machine tool grinding tool spindle, 11. Grinding tool spindle transmission mechanism, 12. Grinding Tool spindle motor, 13. X-direction feed system, 14. Z-direction feed system, 15. Grinding and polishing fluid nozzle, 16. Y-direction feed system, 17. Numerical control system, 18. Computer.

Detailed ways

The present invention will be further specifically described below in conjunction with the accompanying drawings, but the embodiments of the present invention are not limited thereto.

With reference to Fig. 1, the principle that the present invention utilizes magneto-rheological effect to make smooth surface grinding tool is that magnetic body 1 is placed in the grinding and polishing fluid (magnetorheological fluid and abrasive mixture) 3, and magnetorheological The ferromagnetic particles 3-1 in the liquid are arranged in series along the magnetic force lines, and the abrasive particles 3-2 mixed into it are wrapped and confined between the ferromagnetic particles 3-1 distributed in series, because the magnetic force lines at the end of the magnetic body 1 are dense and radial Therefore, the free abrasive aggregates to form a magneto-rheological effect grinding brush 4 with a certain rigidity and bonding strength that can be used for grinding and polishing.

Fig. 2 has shown the principle diagram that the present invention is used for smooth plane grinding and polishing process, as seen from the figure, the workpiece 2-1 that processing surface is plane is installed on the rotary table 5, and lattice type magnetic plane grinding tool 1-1 or The distributed magnetic plane grinding tool 1-2 has rotary and axial feed motions, and the grinding and polishing fluid (magnetorheological fluid and abrasive mixture) 3 is injected from the grinding and polishing fluid nozzle 15 to the interface between the tool and the workpiece to realize the grinding of the workpiece. Grinding and polishing processing. The lattice type magnetic plane grinding tool 1-1 may have the structure shown in Fig. 5, and there are several fine rod-shaped magnetic bodies 1-1-1 or 1-1 distributed on the lattice type magnetic plane grinding tool 1-1. -2, forming an array of magneto-rheological effect grinding brushes 4, the base body of the dot-matrix magnetic planar grinding tool 1-1 is made of non-magnetic material. As shown in Figure 6, the magnetic body 1 in the shape of a fine rod column can be made of a unit permanent magnet column 1-1-1, or can be made of a unit ferromagnetic column 1-1-2 through a DC power supply 1-1-3 And electromagnetic coil 1-1-4 made. The distributed magnetic plane grinding tool 1-2 can be the structure shown in Figure 7, consisting of a distributed magnetic plane grinding tool magnetic body 1-2-1, a copper partition strip 1-2-2, and a magnetic isolation washer 1-2-3 , composed of electromagnetic coils or permanent magnetic ferrules 1-2-4, distributed magnetic plane grinding tool 1-2 is made of ferromagnetic material, magnetic body 1-2-1 is divided into rings by copper dividing belt 1-1-3 The shape structure forms a distributed magnetic field, and a magnetorheological effect grinding belt is formed in the grinding and polishing liquid (mixed liquid of magnetorheological fluid and abrasive material) 3 .

Fig. 3 has shown the principle diagram that the present invention is used for grinding and polishing of smooth axisymmetric rotary curved surface, as can be seen from the figure, the workpiece 2-2 whose processing surface is an axisymmetric rotary curved surface is installed on the rotary table 5, and the magnetic curved surface grinding tool 1 -3 has rotary and axial feed motions, and the polishing liquid (magnetorheological fluid and abrasive mixture) 3 is injected from the polishing liquid nozzle 15 to the interface between the tool and the workpiece to realize grinding and polishing of the curved surface of the workpiece. Fig. 4 has shown the principle diagram that the present invention is used for smooth non-axisymmetric curved surface grinding process, as can be seen from the figure, the workpiece 2-3 that processing surface is non-axisymmetric curved surface is installed on the workbench 5 with numerical control interpolation motion, magnetic The curved surface grinding tools 1-3 have rotary and axial feed movements, and the grinding and polishing fluid (magnetorheological fluid and abrasive mixture) 3 is injected from the grinding and polishing fluid nozzle 15 to the interface between the tool and the workpiece to achieve grinding and polishing of the curved surface of the workpiece processing.

Fig. 8 shows a specific structure of the magnetic curved surface grinding tool 1-3, which is composed of a magnetic curved surface grinding tool substrate 1-3-1 and a permanent magnet 1-3-2 with a circular arc section, forming a magnetic flow with a circular arc section Variation effect grinding brush. Fig. 9 has shown another kind of specific structure of magnetic curved surface grinding tool 1-3, by magnetic curved surface grinding tool base body 1-3-1, electromagnetic coil or permanent magnetic ferrule 1-3-3, magnetic isolation washer 134, copper Composed of dividing strip 1-3-5 and distributed magnetic body 1-3-6 with arc cross-section shape, distributed magnetic body 1-3-6 with arc cross-section shape is made of ferromagnetic material through copper split strip 1-3 -5 split to form a distributed magnetic field and a magneto-rheological effect grinding belt with a circular arc section.

Example 1:

Fig. 10 shows the concrete structure that the present invention is used for ultra-smooth plane grinding and polishing processing, by array type magnetic plane grinding tool 1-1 or distributed magnetic plane grinding tool 1-2, conductive copper ring slider assembly 9, DC power supply 1-1-3, etc. constitute a macro plane grinding tool, the grinding tool is connected with the grinding disc spindle 10 of the machine tool, the grinding tool spindle motor 12 realizes the rotary motion of the plane grinding tool through the grinding tool spindle transmission mechanism 11, and is installed on the body stand The X-direction feeding system 13 and the Z-direction feeding system 14 of the grinding tool on the 8 can realize the X-direction and Z-direction feeding of the magnetic plane grinding tool 1-1. The workpiece 2-1 with a flat processing surface is installed on the rotary table 5, the rotary table 5 is connected with the rotary table spindle 6, the rotary table spindle motor and the transmission mechanism 6 realize the rotary motion, and the grinding and polishing fluid nozzle 15 is used for filling. Grinding and polishing fluid (mixture of magnetorheological fluid and abrasive) 3 reaches the interface between the tool and the workpiece to realize the grinding process of the workpiece.

Example 2:

Fig. 11 has shown the concrete structure that the present invention is used for ultra-smooth curved surface grinding and polishing processing, curved surface magnetic grinding tool 1-3 can realize rotation under the drive of grinding tool spindle motor 12, and processing surface is the workpiece 2- of non-axisymmetric curved surface 3 Installed on the workbench 5 with 3-axis numerical control interpolation movement, the X-direction feed system 13, Z-direction feed system 14 and Y-direction feed system 16 realize the curved surface magnetic grinding tool under the control of the numerical control system 17 1- 3 and the interpolation movement between the workpiece 2-3 whose processing surface is a non-axisymmetric curved surface, the computer 18 transmits the processing data to the numerical control system 17, and the grinding and polishing liquid nozzle 15 is filled with the grinding and polishing liquid (the magnetorheological fluid is mixed with the abrasive material) Liquid) 3 to the interface between the tool and the workpiece to achieve grinding of the curved surface of the workpiece.

Example 3:

The present invention can also grind and polish a convex curved surface or a curved surface with a combination of convex and concave, and its implementation process is similar to the above process.

Claims (11)

1. a grinding and polishing method based on magnetorheological effect, is characterized in that: in magnetorheological fluid, add free abrasive as grinding and polishing fluid and inject between magnetic body and workpiece surface, under the effect of magnetic field, in magnetorheological fluid The ferromagnetic particles are arranged in series to wrap and constrain the abrasive particles on the end surface of the magnetic body to form a magnetic grinding brush and a grinding tool to grind and polish the surface of the workpiece. 2. According to the described magnetorheological effect grinding and polishing method of claim 1, it is characterized in that: the above-mentioned magnetorheological fluid can be selected from the existing commercial magnetorheological fluid, and can also select the following magnetorheological fluid composed of its parts by weight Liquid: 50-60% by weight of silicone oil, 30-40% by weight of solid dispersed particles, 2-3% by weight of oleic acid, 3-15% by weight of abrasive materials; the solid dispersed particles of the self-made magnetorheological fluid are iron As the magnetic material, carbonyl iron powder and reduced iron powder are selected. 3. according to the described magnetorheological effect grinding and polishing method of claim 1, it is characterized in that: the free abrasive that adds in the above-mentioned magnetorheological fluid has silicon carbide (SiC), diamond, cubic nitride (CBN), trioxide One or more mixtures of aluminum (A1 ₂ O ₃ ), silicon nitride (Si ₃ N ₄ ), and zirconia (ZrO ₂ ), the diameter of abrasive particles is less than 20 microns, and the weight of free abrasive and magnetorheological fluid The percentage is less than 15%. 4. The magnetorheological effect grinding and polishing method according to claim 1 is characterized in that: the above-mentioned magnetic body can be a permanent magnet or an electromagnet, and the magnetic body can be a grinding and polishing method composed of a plurality of magnetic rod columns arranged in a lattice. The tool can also be a grinding and polishing tool composed of a distributed magnetic field; the above-mentioned workpiece material can be ceramics, glass, non-metallic hard and brittle materials, or non-magnetic stainless steel metal materials. 5. A magneto-rheological effect grinding plane polishing device according to claim 1, wherein the workpiece with a processing surface as a plane is installed on a rotary table, the rotary table is connected with the main shaft of the rotary table, and the main shaft of the rotary table is connected with the rotary table The main shaft motor is connected to the transmission mechanism; the grinding tool X-direction feeding system and the grinding tool Z-direction feeding system are installed on the body frame and connected to the main shaft of the grinding disc of the machine tool, the main shaft motor of the grinding tool is connected to the transmission mechanism of the main shaft of the grinding tool, and the machine tool The main shaft of the grinding disc is connected with the transmission mechanism of the main shaft of the grinding tool and installed on the frame of the machine body. It is characterized in that: the main shaft of the grinding disc of the machine tool is equipped with a grinding tool, and the grinding and polishing liquid is injected into the gap between the grinding tool and the workpiece through the grinding and polishing liquid nozzle. The above-mentioned grinding and polishing liquid is a mixture of magnetorheological fluid and abrasive, and the free abrasive particles in the above-mentioned grinding and polishing liquid are wrapped and bound together by ferromagnetic particle chains in the magnetorheological fluid to form a magnetorheological effect grinding brush. 6 . The plane grinding and polishing device according to claim 5 , wherein the grinding tool is a dot matrix magnetic plane grinding tool; and the grinding tool is a distributed magnetic plane grinding tool. 7 . 7. The plane grinding and polishing device according to claim 6, characterized in that: the above-mentioned lattice type magnetic plane grinding tool is distributed with some magnetic bodies in the shape of tiny rods to form an array of magneto-rheological effect grinding brushes, and the above-mentioned lattice The base body of the type magnetic plane grinding tool is made of non-magnetic material, and the magnetic body in the shape of a fine rod column is a unit permanent magnet cylinder or a unit ferromagnetic cylinder. Copper ring slider assembly connection; The above-mentioned distributed magnetic plane grinding tool is made of ferromagnetic material. The magnetic body of the distributed magnetic plane grinding tool is divided into a ring structure by a copper partition belt. The magnetic isolation gasket is installed between the magnetic body of the distributed magnetic plane grinding tool and the distributed magnetic plane. Between the grinding tool substrates, the distributed magnetic plane grinding tool base is inlaid with electromagnetic coils or permanent magnetic ferrules, and the distributed magnetic plane grinding tool base is made of non-magnetic materials. 8. A magneto-rheological effect grinding curved surface polishing device according to claim 1, the workpiece is installed on the workbench, the X-direction feed system and the Y-direction feed system are respectively connected to the workbench and the numerical control system, and the numerical control system is connected to the computer , the Z-direction feed system is installed on the fuselage stand and connected with the numerical control system; the grinding tool spindle motor is installed at the lower end of the fuselage stand. Inject the grinding and polishing liquid between the grinding tool and the workpiece; the above-mentioned grinding and polishing liquid is a mixture of magnetorheological fluid and abrasive, and the free abrasive particles in the above-mentioned grinding and polishing liquid are wrapped and bound by the ferromagnetic particle chains in the magnetorheological fluid. Together they form a magneto-rheological effect grinding brush. 9. The curved surface polishing device according to claim 8, characterized in that: said grinding tool is a combined magnetic curved surface grinding tool; said grinding tool is another distributed magnetic curved surface grinding tool. 10. The curved surface polishing device according to claim 9, characterized in that: the combined magnetic curved surface grinding tool is composed of a magnetic curved surface grinding tool substrate and a permanent magnet with an arc section, forming a magneto-rheological effect grinding brush with an arc section ; The above-mentioned permanent magnets with circular arc sections are installed around the base of the magnetic surface grinding tool; The above-mentioned distributed magnetic curved surface grinding tool is composed of a magnetic curved surface grinding tool substrate, an electromagnetic coil or a permanent magnet ferrule, a magnetic isolation washer, a copper partition strip and a distributed magnetic body with an arc cross-section shape; the arc cross-sectional shape distributed magnetic body consists of It is made of ferromagnetic material and divided by copper partition belt to form a distributed magnetic field and a magneto-rheological effect grinding belt with a circular arc cross-section. The electromagnetic coil or permanent magnetic ferrule is embedded in the base of the magnetic surface grinding tool, and the magnetic isolation washer is installed on the magnetic surface. Between the base body of the grinding tool and the distributed magnetic body with a circular arc cross section.

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