A method, system and apparatus for modifying low temperature grinding wheel abrasive based on hydroxyl groups

Abstract

The application provides a low-temperature grinding wheel abrasive particle dressing method, system and device based on hydroxyl modification, comprising: controlling rotation of a polishing disc and spraying hydroxyl radicals on the polishing disc to form a modified layer on the polishing disc; controlling rotation of a grinding wheel to be dressed and abutting against the modified layer on the polishing disc to make the abutting surface undergo hydroxyl dehydration condensation reaction, and the part of the grinding wheel that undergoes hydroxyl dehydration condensation reaction is removed in an atomic level layer-by-layer material removal manner under mechanical shearing action generated by relative motion of the grinding wheel and the polishing disc. The application uses a mixed gas of argon and water vapor, excites microwave plasma in a low-temperature manner, realizes micro-removal of diamond with small mechanical force, and further achieves dressing of resin-based sintered grinding wheels, and removes diamond in an atomic level layer-by-layer removal manner, so that the resin-based sintered grinding wheel surface can achieve lower roughness and realize higher smoothness of the diamond surface.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of grinding wheel dressing, and in particular to a low-temperature grinding wheel abrasive dressing method, system and device based on hydroxyl modification. BACKGROUND

[0002] In the process of precision grinding, stable surface processing quality depends on the state of the diamond abrasive grain of the grinding wheel, so the key to achieving high surface processing quality grinding lies in controlling the diamond abrasive grain edge shape. The existing control of diamond abrasive grain edge shape steps include dressing and dressing, which can make the diamond abrasive grain edge, and dressing can change the diamond abrasive grain edge shape. The existing grinding wheel dressing technology includes mechanical dressing, laser dressing and discharge auxiliary dressing. Mechanical dressing is a mechanical dressing technology that uses a high-speed rotating dressing wheel to remove the edge of the diamond abrasive grain by thermal chemical grinding; laser dressing is to inject a laser beam along the tangent direction of the grinding wheel surface, and use the continuous high temperature to remove the diamond abrasive grain by thermal chemical method; discharge auxiliary dressing is to use the discharge gap formed by the chip and the binder to generate pulse discharge, and the discharge heat is transferred to the abrasive grain edge and coupled with the cutting heat to cause the surface layer to rise in temperature, and the graphitized layer is removed under the action of cutting force.

[0003] Compared with electroplated grinding wheel and metal-based sintered grinding wheel, resin-based sintered grinding wheel has soft binder texture and high elasticity, and is usually used for the last process of grinding processing to obtain better surface quality. However, the binder of resin-based sintered grinding wheel has low melting point and the abrasive grain is easy to fall off, and there is currently no dressing method for resin-based sintered grinding wheel. SUMMARY

[0004] Therefore, the present application provides a low-temperature grinding wheel abrasive dressing method, system and device based on hydroxyl modification, and the specific solutions are as follows:

[0005] Firstly, the present application provides a low-temperature grinding wheel abrasive dressing method based on hydroxyl modification, which comprises the following steps:

[0006] controlling the rotation of the polishing disc, and controlling the spraying of hydroxyl radicals on the polishing disc, so that the sprayed area on the polishing disc forms a low-temperature modified layer;

[0007] controlling the rotation of the grinding wheel to be dressed, and making the grinding wheel abut against the modified layer on the polishing disc, so that the contact surface of the grinding wheel abutting against the modified layer undergoes hydroxyl dehydration condensation reaction, and the part of the grinding wheel undergoing hydroxyl dehydration condensation reaction is removed in the form of atomic-level layer-by-layer material removal under the mechanical shearing action generated by the relative motion of the grinding wheel and the polishing disc.

[0008] In one embodiment, the polishing disc comprises a planar polishing disc, and the "controlling the spraying of hydroxyl radicals on the polishing disc" comprises:

[0009] controlling the hydroxyl radicals to be sprayed on a flat polishing surface of the polishing disc; a distance between a spraying position of the substance on the flat polishing surface and a rotation center of the polishing disc is equal to a distance between the grinding wheel and the rotation center.

[0010] In one embodiment, the polishing disc has a shape of a circular truncated cone, and a rotation center axis of the polishing disc is a center axis of the circular truncated cone.

[0011] The controlling the hydroxyl radicals to be sprayed on the polishing disc includes controlling the hydroxyl radicals to be sprayed on a side surface of the polishing disc having the shape of the circular truncated cone.

[0012] The making the grinding wheel abut against the modified layer on the polishing disc includes making one side of the grinding wheel abut against the modified layer on one side of the polishing disc having the shape of the circular truncated cone, and making another side of the grinding wheel abut against the modified layer on another side of the polishing disc having the shape of the circular truncated cone after the one side of the grinding wheel is finished.

[0013] In one embodiment, the polishing disc rotates in the same direction as the grinding wheel.

[0014] In one embodiment, the polishing disc is a rigid polishing disc.

[0015] The modified layer has a hardness less than a hardness of a remaining part of the polishing disc except the modified layer.

[0016] In one embodiment, the making the grinding wheel abut against the modified layer on the polishing disc includes applying a preset load to the grinding wheel to make the grinding wheel abut against the modified layer on the polishing disc, and the preset load is in a range of 1N-4N.

[0017] In one embodiment, the hydroxyl radicals are generated by a microwave plasma, and the hydroxyl radicals are generated by exciting a mixed gas of water vapor and argon gas by the microwave plasma.

[0018] In one embodiment, the method further includes exciting the microwave plasma by a preset microwave power to make a temperature applied to the grinding wheel lower than a melting point of a binder in the grinding wheel for binding abrasive particles.

[0019] The preset microwave power is in a range of 150w-225w.

[0020] In the second part, the application provides a low-temperature grinding wheel abrasive particle dressing system based on hydroxyl modification, which includes:

[0021] A control module is configured to control rotation of the polishing disc and to control injection of hydroxyl radicals on the polishing disc so as to form a modified layer with low temperature on the region of the polishing disc being injected with the hydroxyl radicals.

[0022] A dressing module is configured to control rotation of the grinding wheel to be dressed and to make the grinding wheel abut against the modified layer on the polishing disc so as to cause a hydroxyl dehydration condensation reaction on the contact surface of the grinding wheel abutting against the modified layer and to dress the part of the grinding wheel where the hydroxyl dehydration condensation reaction occurs in a way of atomic-level layer-by-layer material removal under mechanical shearing action generated by relative motion of the grinding wheel and the polishing disc.

[0023] In a third part, the application provides a low-temperature grinding wheel abrasive dressing device based on hydroxyl modification, which is used to perform the low-temperature grinding wheel abrasive dressing method based on hydroxyl modification mentioned above. The device comprises a polishing disc, a movable clamp, a plasma torch pipe for injecting microwave plasma, and a driving part. The plasma torch pipe is provided with a nozzle facing the polishing disc, and the driving part drives the polishing disc and the movable clamp respectively to control the relative motion of the polishing disc and the movable clamp. The movable clamp is used to control the grinding wheel to be dressed to abut against the polishing disc.

[0024] Advantages:

[0025] The application uses a mixed gas of argon and water vapor, excites microwave plasma in a low-temperature mode, and realizes micro-removal of diamond with small mechanical force, thereby achieving dressing of the resin-based sintered grinding wheel. The diamond is removed in a way of atomic-level layer-by-layer removal, so that the surface of the resin-based sintered grinding wheel can achieve lower roughness and higher smoothness of the diamond surface. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is a flow chart of the low-temperature grinding wheel abrasive dressing method based on hydroxyl modification according to an embodiment of the application;

[0027] Figure 2 is a structural diagram of the low-temperature grinding wheel abrasive dressing system based on hydroxyl modification according to an embodiment of the application;

[0028] Figure 3 is a schematic diagram of the grinding wheel abrasive dressing device according to an embodiment of the application;

[0029] Figure 4 is a profile diagram of the disc-shaped polishing disc according to an embodiment of the application;

[0030] Figure 5 is a process schematic diagram of the low-temperature grinding wheel abrasive dressing method based on hydroxyl modification according to an embodiment of the application;

[0031] Figure 6is a schematic diagram of characteristic spectra excited before and after the plasma is introduced into water vapor according to an embodiment of the present application;

[0032] Figure 7 is a graph of microwave plasma power versus temperature according to an embodiment of the present application;

[0033] Figure 8 is a schematic diagram of the appearance of a resin-based sintered grinding wheel before being modified by microwave plasma according to an embodiment of the present application;

[0034] Figure 9 is a schematic diagram of the appearance of a resin-based sintered grinding wheel after being modified by microwave plasma according to an embodiment of the present application;

[0035] Figure 10 is a 3D schematic diagram of a resin-based sintered grinding wheel before being modified by microwave plasma according to an embodiment of the present application;

[0036] Figure 11 is a 3D schematic diagram of a resin-based sintered grinding wheel after being modified by microwave plasma according to an embodiment of the present application;

[0037] Figure 12 is a schematic diagram of the contour of a plurality of abrasive grains of a resin-based sintered grinding wheel after being modified according to an embodiment of the present application;

[0038] Figure 13 is a schematic diagram of diamond shedding analysis of a resin-based sintered grinding wheel before being modified under maximum load according to an embodiment of the present application;

[0039] Figure 14 is a schematic diagram of diamond shedding analysis of a resin-based sintered grinding wheel after being modified under maximum load according to an embodiment of the present application.

[0040] The reference numerals: 1 - polishing disc; 2 - grinding wheel; 3 - modified layer; 4 - movable clamp; 5 - plasma torch tube; 6 - driving part; 7 - control module; 8 - modification module. DETAILED DESCRIPTION

[0041] Hereinafter, various embodiments of the present disclosure will be described more fully. The present disclosure can have various embodiments, and adjustments and changes can be made therein. However, it should be understood that there is no intention to limit various embodiments of the present disclosure to the specific embodiments disclosed herein, but the present disclosure should be understood to encompass all adjustments, equivalents, and / or alternatives falling within the spirit and scope of various embodiments of the present disclosure.

[0042] The terms used in the various embodiments of the present disclosure are used only for the purpose of describing particular embodiments and are not intended to limit the various embodiments of the present disclosure. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the various embodiments of the present disclosure belong. The terms (such as terms defined in a generally used dictionary) will be interpreted as having the same meaning as the context in the related technical field and will not be interpreted as having idealized or overly formal meanings, unless clearly defined in the various embodiments of the present disclosure.

[0043] Embodiment 1

[0044] The present disclosure uses a mixture of argon and water vapor to excite microwave plasma in a low-temperature manner to achieve micro-removal of diamonds with small mechanical force, thereby achieving dressing of resin-bonded sintered grinding wheels. And by removing diamonds layer by layer at the atomic level, the resin-bonded sintered grinding wheel surface can achieve lower roughness and higher smoothness of the diamond surface. The specific scheme is as follows:

[0045] The method mentioned in this embodiment is a grinding wheel 2 abrasive dressing method based on hydroxyl modification, as shown in the accompanying Figure 1 -attached Figure 3 As shown, it includes:

[0046] 101. Control the rotating polishing disc 1, and control the spraying of hydroxyl radicals on the polishing disc 1, so that the sprayed area on the polishing disc 1 forms a low-temperature modified layer 3. This embodiment adopts an advanced grinding wheel dressing technology, in which the key steps include controlling the rotating polishing disc 1 and spraying hydroxyl radicals thereon.

[0047] Specifically, as shown in the accompanying Figure 3 The grinding wheel 2 sample is tightly attached to the polishing disc under the action of the load force F, the microwave plasma source rich in hydroxyl radicals (OH) is sprayed from the plasma torch pipe 5 at a preset flow rate, irradiates the surface of the polishing disc 1 and reacts chemically, forming a low-hardness modified layer on the surface of the polishing disc 1 in a low-temperature manner. In this embodiment, the grinding wheel is selected as a resin-bonded sintered grinding wheel, and the low-temperature range is room temperature (20°-25°)-the melting point of the resin binder (250°). The temperature during dressing is lower than the melting point of the resin binder, which can achieve effective dressing of the resin-bonded sintered grinding wheel. In actual application, the rotating speed and direction of the polishing disc 1 can be accurately controlled, so that the sprayed microwave plasma can uniformly cover the surface, so as to form a uniform and high-quality modified layer 3.

[0048] In the present embodiment, the way of generating hydroxyl radicals includes microwave plasma. Hydroxyl radicals are highly active chemical substances that can chemically react with the material on the surface of the polishing disc 1, thereby changing the chemical properties of its surface. During the spraying process, the spraying intensity, temperature and concentration of the microwave plasma can also be closely monitored to ensure that a uniform modified layer 3 can be formed on the surface of the polishing disc 1.

[0049] 102. The rotating grinding wheel 2 to be dressed is controlled, and the grinding wheel 2 is made to abut against the modified layer 3 on the polishing disc 1, so that the contact surface of the grinding wheel 2 abutting against the modified layer 3 undergoes hydroxyl dehydration condensation reaction, and the part of the grinding wheel 2 that undergoes hydroxyl dehydration condensation reaction is removed in an atomic-level layer-by-layer material removal manner under the mechanical shearing action generated by the relative motion of the grinding wheel 2 and the polishing disc 1. In order to achieve the dressing of the grinding wheel 2, the present embodiment further includes precise control and interaction between the grinding wheel 2 and the polishing disc 1.

[0050] Specifically, while the polishing disc 1 is controlled to rotate, the grinding wheel 2 to be dressed is controlled to stably and accurately rotate. The polishing disc 1 and the grinding wheel 2 rotate in the same direction at rotational speeds Vp and Vd, respectively, and the modified layer 3 is rotated by the polishing disc 1 to the grinding wheel dressing area. The plasma irradiation area and the grinding wheel dressing area are at the same distance from the center of the rotating disc, i.e. Figure 3 The high-activity hydroxyl radicals adhere to the polishing disc 1 and the grinding wheel 2 and form bonds with specific atoms of the two, resulting in a modification effect, and then hydroxyl dehydration condensation reaction CD-OH + M-OH → CD-O-M + H2O (CD refers to carbon atoms on the surface of the grinding wheel 2 modified by hydroxyl, and M refers to atoms on the surface of the polishing disc 1 modified by hydroxyl) occurs at the interface between the two, forming a new bond CD-O-M. Under the mechanical shearing action, the surface CD-CD of the grinding wheel 2 breaks, and the part that undergoes hydroxyl dehydration condensation reaction is removed in an atomic-level layer-by-layer material removal manner under the mechanical shearing action generated by the relative motion of the grinding wheel 2 and the polishing disc 1. Since the raised parts on the surface of the grinding wheel 2 are more likely to capture hydroxyl radicals and have a higher material removal rate, the surface flatness of the grinding wheel 2 will eventually approach that of the polishing disc 1, thereby achieving global flattening of the grinding wheel 2.

[0051] It should be noted that the microwave plasma here acts on the polishing disc 1, and the hydroxyl radicals on the grinding wheel 2 are brought to the grinding wheel dressing area by the rotation of the polishing disc 1, rather than the microwave plasma directly acting on the grinding wheel abrasive, thereby ensuring that the grinding performance of the surface of the grinding wheel 2 will not change.

[0052] Specifically, a 100# resin-based grinding wheel is used, with a microwave power of 200W and a 1N load. Hydroxyl-containing plasma (8slm argon, 140sccm water vapor) is introduced, and the grinding wheel rotates at 2rpm and the polishing disc rotates at 200rpm for 30 minutes. The experimental results are shown in the accompanying Figure 8 -attached Figure 12 As shown in the accompanying Figure 12 As shown in the accompanying

[0053] In one embodiment, the polishing disc 1 includes: a planar polishing disc 1; "controlling the spraying of hydroxyl radicals on the polishing disc 1" includes:

[0054] Controlling the spraying of hydroxyl radicals on the planar polishing surface of the polishing disc 1; the distance between the spraying position of the sprayed substance on the planar polishing surface and the center of rotation of the polishing disc 1 is equal to the distance between the grinding wheel 2 and the center of rotation.

[0055] As shown in the accompanying Figure 3 The polishing disc 1 of the present embodiment can adopt a planar polishing disc structure, which ensures the flatness and uniformity of the polishing disc surface, providing a stable foundation for subsequent grinding wheel dressing process.

[0056] When performing the step of "controlling the spraying of hydroxyl radicals on the polishing disc 1", the spraying of the substance on the planar polishing surface of the polishing disc 1 is precisely controlled, ensuring that the sprayed plasma can uniformly cover the entire polishing surface.

[0057] To ensure that the interaction between the grinding wheel 2 and the polishing disc 1 achieves the best effect, the spraying position of the substance is further adjusted. Specifically, the distance between the spraying position of the substance on the planar polishing surface and the center of rotation of the polishing disc 1 is equal to the distance between the grinding wheel 2 and the center of rotation. This design ensures that the surface of the grinding wheel 2 and the modified layer 3 on the polishing disc 1 can always maintain a constant distance and contact area during rotation, thereby achieving more uniform and efficient grinding wheel dressing.

[0058] Through this precise control and adjustment, not only can the grinding wheel 2 be precisely dressed, but also the dressing efficiency and quality can be maximized. This grinding wheel dressing technique is not only suitable for resin-based sintered grinding wheels, but also can be applied to other types of grinding wheel dressing processes.

[0059] In one embodiment, the shape of the polishing disc 1 includes a circular truncated cone, and the center axis of rotation of the polishing disc 1 is the center axis of the circular truncated cone;

[0060] "Controlling the spraying of hydroxyl radicals on polishing disc 1" includes: controlling the spraying of hydroxyl radicals on the side of the frustum-shaped polishing disc 1;

[0061] "Making the grinding wheel 2 abut against the modified layer 3 on the polishing disc 1" includes: making one side of the grinding wheel 2 to be dressed abut against the modified layer 3 on one side of the frustum-shaped polishing disc 1; if one side of the grinding wheel 2 to be dressed is dressed, making the other side of the grinding wheel 2 to be dressed abut against the modified layer 3 on the other side of the frustum-shaped polishing disc 1.

[0062] As attached Figure 4 As shown, the polishing disc 1 in this embodiment can also be truncated cone-shaped. This truncated cone design not only enhances the structural stability of the polishing disc 1, but also brings unique advantages to its functional characteristics. The rotation center axis of the polishing disc 1 is set as the center axis of the truncated cone, which ensures that the polishing disc 1 can maintain a uniform rotation speed and a stable rotation trajectory when rotating.

[0063] In the step of "controlling the spraying of hydroxyl radicals onto the polishing disc 1", the spraying is controlled to occur on the side of the frustum-shaped polishing disc 1, allowing the material to uniformly cover the side of the polishing disc, thereby forming a uniform modified layer 3. Further, one side of the grinding wheel 2, the surface to be dressed, is brought into contact with the modified layer 3 on one side of the frustum-shaped polishing disc 1. In this way, during the rotation and feeding of the grinding wheel 2, the surface to be dressed can fully contact and rub against the modified layer, thereby achieving the dressing of the grinding wheel 2.

[0064] After one side of the grinding wheel 2 has been dressed, it is rotated so that the other side of the grinding wheel 2 can come into contact with the modified layer 3 on the other side of the frustum-shaped polishing disc 1. This design not only improves dressing efficiency but also avoids errors and damage that may occur during the removal and reinstallation of the grinding wheel 2.

[0065] In this way, the grinding wheel 2 can be fully dressed, greatly improving dressing efficiency and quality. At the same time, the frustum-shaped design of the polishing disc 1 and the side-jetting microwave plasma method make the entire dressing process more stable and reliable.

[0066] In one specific embodiment, the polishing disc 1 rotates in the same direction as the grinding wheel 2. The fact that the polishing disc 1 and the grinding wheel 2 rotate in the same direction significantly reduces the friction and resistance generated when they come into contact. This helps to achieve a smoother and more stable dressing process, avoiding problems such as damage to the grinding wheel surface or premature wear of the polishing disc due to excessive friction.

[0067] Secondly, the same direction of rotation also helps to improve the uniformity and consistency of dressing. When the grinding wheel 2 and the polishing disc 1 rotate in the same direction, each point on the surface of the grinding wheel 2 can fully contact and rub with the modified layer on the polishing disc 1, thereby ensuring the uniform distribution of the dressing effect. This uniform dressing effect can improve the machining precision and efficiency of the grinding wheel. In addition, the same direction of rotation also helps to reduce noise and vibration during operation. Since the rotation directions of the two are consistent, the vibration and noise generated by relative motion can be significantly reduced.

[0068] In one specific embodiment, the polishing disc 1 comprises a rigid polishing disc 1;

[0069] The hardness of the modified layer 3 is less than the hardness of the rest of the polishing disc 1 except the modified layer 3.

[0070] In this embodiment, the polishing disc 1 adopts the structure of a rigid polishing disc. This rigid polishing disc not only has excellent structural strength and stability, but also can maintain the stability of the shape during high-speed rotation and contact with the grinding wheel, ensuring the precision and reliability of the dressing process.

[0071] Further, the hardness of the modified layer 3 is less than the hardness of the rest of the polishing disc 1 except the modified layer 3, which can better adapt to the characteristics of the resin-based sintered grinding wheel binder, which is soft in texture and has high elasticity, thereby providing more uniform and delicate dressing effect. In addition, the hardness of the modified layer 3 allows it to deform to a certain extent when it comes into contact with the grinding wheel, filling the small recesses and protrusions on the surface of the grinding wheel 2. This deformation makes the contact between the grinding wheel 2 and the polishing disc 1 more intimate, improving the efficiency and precision of the dressing.

[0072] In one specific embodiment, "abutting the modified layer 3 on the polishing disc 1 with the grinding wheel 2" comprises: applying a predetermined load force to the grinding wheel 2 to abut the modified layer 3 on the polishing disc 1 with the grinding wheel 2. In this embodiment, the method of generating hydroxyl radicals is microwave plasma, and the range of the predetermined load force is 1N-4N. Within this range of load force, the diamond abrasive grains on the grinding wheel 2 will not fall off when the grinding wheel 2 is dressed. Under the condition of microwave power 200W, hydroxyl-containing plasma (8slm argon, 140sccm water vapor) is introduced, the grinding wheel 2 rotates at 60rpm, the polishing disc 1 rotates at 200rpm, and the processing time is 30min. The maximum processing load is 4N, and the morphology and whether the diamonds fall off after dressing are observed. The results are shown in Figures 1-4. Figure 13 and Figures 1-4. Figure 14As shown in the figure, it can be seen that the flat surface of the diamond surface after the microwave plasma modification becomes larger, and the diamonds on the grinding wheel 2 do not fall off, and the 5 out of blade abrasive grains before processing are still 5 out of blade abrasive grains after modification, and the top surface of the 2,3 abrasive grains becomes larger after modification. The load used in the microwave plasma processing is lower than that in general grinding, so the diamonds will not fall off during the modification.

[0073] By applying a preset load force to the grinding wheel 2, the grinding wheel 2 and the modified layer 3 on the polishing disc 1 achieve stable and uniform contact. This contact state not only ensures that the micro-unevenness on the surface of the grinding wheel 2 is effectively removed, but also enables the surface of the grinding wheel 2 to be uniformly worn and modified. At the same time, due to the reasonable control of the preset load force, it can also avoid the problems of performance degradation or damage of the surface of the grinding wheel 2 due to excessive wear.

[0074] In one specific embodiment, the way to generate hydroxyl radicals includes microwave plasma, and the generation of hydroxyl radicals is obtained by exciting the mixed gas of water vapor and argon through microwave plasma. As shown in the figure, Figure 6 As shown in the figure, the activity of free radicals in the two plasmas is compared by optical emission spectrometry (OES) when the reaction gas is passed through water vapor and not passed through water vapor, and other experimental conditions are a load of 1N, a microwave power of 200W, a grinding wheel speed of 60rpm, and a silicon disc speed of 200rpm for 30min of processing. The results are shown in the figure Figure 6 As shown in the figure, the activity of hydroxyl radicals passed through water vapor is higher than that not passed through water vapor at a wavelength of λ = 309nm, which can make the polishing disc and the diamond surface adhere to more active hydroxyl radicals, so water vapor is selected as the reaction gas in the microwave plasma modification of the grinding wheel.

[0075] In one specific embodiment, it further includes: exciting the microwave plasma by a preset microwave power, so that the temperature acting on the grinding wheel 2 is lower than the melting point of the binder for bonding the abrasive grains in the grinding wheel 2;

[0076] The preset microwave power ranges from 150w to 225w. As shown in the figure, Figure 7 As shown in the figure, the temperature of the microwave plasma processing resin-based sintered grinding wheel is measured by an infrared thermal imager. The load used is 1N, the microwave power is 200W, the hydroxyl-containing plasma (8slm argon, 140sccm water vapor) is passed in, the grinding wheel speed is 60rpm, the polishing disc speed is 200rpm, and the processing time is 30min. The temperature measurement points are the contact points of the plasma torch pipe 5 and the polishing disc 1 and the contact points of the resin grinding wheel 2 and the polishing disc 1, and the microwave power is selected between 150W and 225W at equal intervals, and the results are shown in the figure Figure 7As shown, the temperature of both measuring points increases with the increase of microwave power, and reaches the maximum at 225W, with the highest temperature of 133.3℃, which is lower than the melting temperature of resin binder 250℃. Therefore, during the dressing process, the power between 150W and 225W is selected, and the resin binder will not be melted, and the effective dressing of the resin-based sintered grinding wheel can be achieved.

[0077] Embodiment Two

[0078] The embodiment provides a grinding wheel 2 abrasive dressing system based on hydroxyl modification, and systematically makes the grinding wheel 2 abrasive dressing method based on hydroxyl modification in embodiment 1 more practical. The specific scheme is as follows:

[0079] A grinding wheel 2 abrasive dressing system based on hydroxyl modification, as shown in the accompanying drawings, comprises: Figure 2

[0080] A control module 7 is configured to control the rotation of the polishing disc 1 and control the spraying of hydroxyl radicals on the polishing disc 1, so that the sprayed area on the polishing disc 1 forms a low-temperature modified layer 3.

[0081] A dressing module 8 is configured to control the rotation of the grinding wheel 2 to be dressed and make the grinding wheel 2 abut against the modified layer 3 on the polishing disc 1, so that the contact surface of the grinding wheel 2 abutting against the modified layer 3 undergoes hydroxyl dehydration condensation reaction, and the part of the grinding wheel 2 undergoing hydroxyl dehydration condensation reaction is removed in the form of atomic-level layer-by-layer material removal under the mechanical shearing action generated by the relative motion of the grinding wheel 2 and the polishing disc 1.

[0082] In one specific embodiment, the polishing disc comprises: a planar polishing disc; the "controlling the spraying of hydroxyl radicals on the polishing disc" comprises:

[0083] controlling the spraying of hydroxyl radicals on the planar polishing surface of the polishing disc; the distance between the spraying position of the spraying substance on the planar polishing surface and the rotation center of the polishing disc is equal to the distance between the grinding wheel and the rotation center.

[0084] In one specific embodiment, the shape of the polishing disc comprises a circular truncated cone, and the rotation center axis of the polishing disc is the center axis of the circular truncated cone.

[0085] The "controlling the spraying of hydroxyl radicals on the polishing disc" comprises: controlling the spraying of hydroxyl radicals on the side surface of the polishing disc in the form of a circular truncated cone.

[0086] The "making the grinding wheel abut against the modified layer on the polishing disc" comprises: making one side of the grinding wheel abut against the modified layer on one side of the polishing disc in the form of a circular truncated cone; and making the other side of the grinding wheel abut against the modified layer on the other side of the polishing disc in the form of a circular truncated cone after the dressing of the one side of the grinding wheel.

[0087] ​In one embodiment, the rotation direction of the polishing disc is the same as the rotation direction of the grinding wheel.

[0088] In one embodiment, the polishing disc comprises a rigid polishing disc.

[0089] The hardness of the modified layer is less than the hardness of the rest of the polishing disc except the modified layer.

[0090] In one embodiment, the "abutting the modified layer on the polishing disc with the grinding wheel" comprises: acting on the grinding wheel with a preset load force to abut the modified layer on the polishing disc with the grinding wheel, and avoiding the abrasive grains from falling off during dressing.

[0091] In one embodiment, the way of generating hydroxyl radicals comprises microwave plasma, and the hydroxyl radicals are generated by exciting the mixed gas of water vapor and argon gas through microwave plasma.

[0092] In one embodiment, the method further comprises: exciting the microwave plasma through a preset microwave power, so that the temperature acting on the grinding wheel is lower than the melting point of the binder in the grinding wheel for bonding the abrasive grains.

[0093] The preset microwave power ranges from 150w to 225w.

[0094] Embodiment three

[0095] The embodiment provides a hydroxyl-modified grinding wheel 2 abrasive grain dressing device, which realizes the device of the hydroxyl-modified grinding wheel 2 abrasive grain dressing method in embodiment 1, and is more practical. The specific scheme is as follows:

[0096] A hydroxyl-modified grinding wheel 2 abrasive grain dressing device, which comprises a polishing disc 1, a movable clamp 4, a plasma torch pipe 5 for spraying microwave plasma, and a driving part 6; the plasma torch pipe 5 is provided with a nozzle facing the polishing disc 1, and the driving part 6 drives the polishing disc 1 and the movable clamp 4 respectively, and is used for controlling the relative motion of the polishing disc 1 and the movable clamp 4; the movable clamp 4 is used for controlling the grinding wheel 2 to be dressed to abut against the polishing disc 1.

[0097] The application uses the mixed gas of argon and water vapor, excites the microwave plasma in a low-temperature mode, and can realize the micro-removal of diamond with small mechanical force, so as to achieve the dressing of the resin-based sintered grinding wheel. And the diamond is removed layer by layer in an atomic level, so that the surface of the resin-based sintered grinding wheel can reach a lower roughness, and the smoothness of the diamond surface is higher.

[0098] Those skilled in the art can understand that the modules or flows in the drawings are not necessarily the modules or flows that must be implemented in the embodiments of the present application. Those skilled in the art can understand that the modules in the devices in the embodiments can be distributed in the devices in the embodiments according to the description of the embodiments, or can be changed to be located in one or more devices different from the embodiments.

Claims

1. A method of modifying a low temperature grinding wheel abrasive based on hydroxyl groups, characterized by, The method comprises: controlling rotation of a polishing disc, and controlling injection of hydroxyl radicals on the polishing disc, so that a region of the polishing disc on which the hydroxyl radicals are injected forms a low-temperature modified layer; controlling rotation of a grinding wheel to be dressed, and making the grinding wheel abut against the modified layer on the polishing disc, so that a contact surface of the grinding wheel which abuts against the modified layer undergoes hydroxyl dehydration condensation reaction, and the part of the grinding wheel which undergoes hydroxyl dehydration condensation reaction is dressed in an atomic layer-by-layer material removal manner under mechanical shearing action generated by relative motion between the grinding wheel and the polishing disc.

2. The method of claim 1, wherein, The polishing disc comprises: a planar polishing disc; the "controlling injection of hydroxyl radicals on the polishing disc" comprises: controlling injection of hydroxyl radicals on a planar polishing surface of the polishing disc; and a distance between an injection position of the hydroxyl radicals on the planar polishing surface and a rotation center of the polishing disc is equal to a distance between the grinding wheel and the rotation center.

3. The method of claim 1, wherein, The polishing disc has a shape of a circular truncated cone, and a rotation center axis of the polishing disc is a center axis of the circular truncated cone; The "controlling injection of hydroxyl radicals on the polishing disc" comprises: controlling injection of hydroxyl radicals on a side surface of the polishing disc which has a shape of a circular truncated cone; The "making the grinding wheel abut against the modified layer on the polishing disc" comprises: making a side surface to be dressed of the grinding wheel abut against the modified layer on a side surface of the polishing disc which has a shape of a circular truncated cone; and after the side surface to be dressed of the grinding wheel is dressed, making another side surface to be dressed of the grinding wheel abut against the modified layer on another side surface of the polishing disc which has a shape of a circular truncated cone.

4. The method of claim 1 or 2, wherein, The rotation direction of the polishing disc is the same as the rotation direction of the grinding wheel.

5. The method of claim 1, wherein, The polishing disc comprises a rigid polishing disc; The hardness of the modified layer is less than the hardness of a remaining part of the polishing disc except the modified layer.

6. The method according to any one of claims 1 to 3, wherein The "making the grinding wheel abut against the modified layer on the polishing disc" comprises: applying a preset load force to the grinding wheel, so that the grinding wheel abuts against the modified layer on the polishing disc; The preset load force ranges from 1 N to 4 N.

7. The method of claim 1, wherein, The hydroxyl radicals are generated by a microwave plasma, and the hydroxyl radicals are generated by passing a mixed gas of water vapor and argon through the microwave plasma excitation.

8. The method of claim 7, wherein, The method further comprises: exciting the microwave plasma by a preset microwave power, so that a temperature applied to the grinding wheel is lower than a melting point of a binder in the grinding wheel which is used to bond abrasive particles; The preset microwave power ranges from 150 W to 225 W.

9. A hydroxyl group-modified low-temperature grinding wheel abrasive particle dressing system, characterized by, The method comprises: a control module, configured to control rotation of a polishing disc, and control injection of hydroxyl radicals on the polishing disc, so that a region of the polishing disc on which the hydroxyl radicals are injected forms a low-temperature modified layer; a dressing module, configured to control rotation of a grinding wheel to be dressed, and make the grinding wheel abut against the modified layer on the polishing disc, so that a contact surface of the grinding wheel which abuts against the modified layer undergoes hydroxyl dehydration condensation reaction, and the part of the grinding wheel which undergoes hydroxyl dehydration condensation reaction is dressed in an atomic layer-by-layer material removal manner under mechanical shearing action generated by relative motion between the grinding wheel and the polishing disc.

10. A low temperature grinding wheel abrasive particle dressing device based on hydroxyl modification, characterized by, The device is used for executing the method in any one of claims 1-8, and comprises a polishing disc, a movable clamp, a plasma torch pipe for spraying microwave plasma, and a driving part; a nozzle is arranged on the plasma torch pipe and faces the polishing disc; the driving part drives the polishing disc and the movable clamp respectively, and controls the relative movement between the polishing disc and the movable clamp; the movable clamp is used for controlling the grinding wheel to be finished to abut against the polishing disc.

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