An ultra-hard abrasive and grinding wheel high-speed precision grinding optimization method based on C / C-SiC material

Abstract

The application discloses a kind of based on C / C-SiC material's superhard abrasive and grinding wheel high-speed precision grinding optimization method, comprising the following steps: S1: system establishes superhard abrasive hardness self-adapting grinding wheel inner and outer runner structure theory, reveal the influence law of the structure change of runner to mixed liquid flow, filling effect, barrier effect;S2: through software simulation analysis and 3D printing runner inner channel simulation mixed liquid flow experiment, analyze the relationship between the curve shape of inner channel, cross section shape, inner channel taper change and mixed liquid flow effect.The based on C / C-SiC material's superhard abrasive and grinding wheel high-speed precision grinding optimization method, by the surface mechanism of MoS2 Nanometer particle directional lubrication grinding force mutation grinding wheel, clarify superhard abrasive hardness self-adapting grinding wheel grinding C / C-SiC material grinding dust formation mechanism, reveal the influence law of runner structure to the effective lubrication of lubricating fluid, chip removal effect, enter to reach the effect of optimizing grinding wheel high-speed precision grinding optimization.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of high-speed precision grinding of grinding wheels, in particular to an ultra-hard abrasive based on C / C-SiC material and a high-speed precision grinding optimization method of grinding wheels. BACKGROUND

[0002] The processing of fiber-reinforced silicon carbide ceramic materials has achieved many satisfactory results, however, the above technical solutions still have the following problems: the fiber-reinforced silicon carbide ceramic material cannot be adjusted according to different grinding fiber angles during grinding, and defects such as fiber pulling, fiber breaking, delamination, fiber matrix debonding and matrix breaking inevitably occur on the workpiece surface. And during the grinding process of the grinding wheel, the abrasive grains are easily embedded into the workpiece surface due to the wear of the grinding wheel, which also causes the embedding of impurities on the processed surface. At the same time, although the overflow grinding fluid grinding provides effective lubrication, this method cannot timely transfer heat out of the grinding area; and during the grinding process of micro-lubrication and nano-micro-lubrication, the oil mist after nozzle atomization is easy to drift, which will have a certain impact on the surrounding environment and health, and also reduce the effective utilization rate of lubricating base oil. Therefore, technical upgrading is needed to meet market demand. SUMMARY

[0003] The purpose of the application is to provide an ultra-hard abrasive based on C / C-SiC material and a high-speed precision grinding optimization method of grinding wheels, to study the mechanism of MoS2 nanoparticle directional lubrication of the grinding surface of the grinding wheel, to explore the mechanism of secondary atomization and fragmentation of the hydroxy guar gum solution, to clarify the mechanism of adhesion of hydroxy guar gum droplets to grinding dust, and to reveal the influence law of the effective lubrication and chip removal effect of the inner flow channel structure on the lubricating liquid, so as to solve the problems raised in the above background technology.

[0004] To achieve the above purpose, the application provides the following technical scheme: an ultra-hard abrasive based on C / C-SiC material and a high-speed precision grinding optimization method of grinding wheels, comprising the following steps:

[0005] S1: establishing a hardness self-adaptive grinding wheel inner and outer flow channel structural theory of the ultra-hard abrasive, and revealing the influence law of the structural change of the flow channel on the flow, filling effect and barrier breaking effect of the mixed liquid;

[0006] S2: analyzing the relationship between the inner flow channel curve shape, cross-sectional shape, inner flow channel taper change and the flow effect of the mixed liquid through software simulation analysis and 3D printing of the inner flow channel simulation mixed liquid flow experiment;

[0007] S3: Study the influence of the percentage of each substance in the hydroxy guar gum mixed solution and the internal structure of the grinding wheel on the secondary atomization and breaking efficiency of the hydroxy guar gum mixed solution, establish a corresponding mathematical model, and simulate the process of the secondary atomization and breaking of the hydroxy guar gum mixed solution after being sprayed out of the grinding wheel, optimize the percentage of each substance in the hydroxy guar gum mixed solution and the internal structure of the grinding wheel;

[0008] S4: Study the atomization and breaking rate of the hydroxy guar gum mixed solution, explore the influence of the physical film formed by the stretching of MoS2 nanoparticles under grinding force on the friction surface on the grinding efficiency and workpiece surface roughness, conduct comparative experiments with traditional grinding, and study the change and influence law of the grinding temperature, grinding force, grinding quality, and grinding wheel wear of the self-adaptive grinding wheel with super-hard abrasive particles;

[0009] S5: The hydroxy guar gum solution is a typical non-Newtonian fluid with high viscosity and poor flowability. Optimizing the internal flow channel structure parameters and achieving uniform distribution of the internal flow channel around the grinding wheel shaft in the base and effective breaking of the air barrier layer on the surface of the grinding wheel are the keys to reducing the kinetic energy loss caused by the mutual impact of the hydroxy guar gum solution and the internal flow channel and breaking through the air barrier layer, and ensuring that the MoS2 nanoparticles fully fill the gap between the grinding dust and abrasive particles in the grinding area of the grinding wheel.

[0010] S6: Study the conditions, process, and mechanism of the secondary atomization of the hydroxy guar gum mixed solution, conduct quantitative analysis of the influencing factors of the secondary atomization, and realize the controllability of the secondary atomization process of the hydroxy guar gum mixed solution.

[0011] S7: Analyze the stress of MoS2 nanoparticles under high speed and high pressure, and explore the influence of the physical film formed by the stretching of MoS2 nanoparticles under grinding force on the friction surface on the grinding efficiency, workpiece surface roughness, and surface / subsurface damage.

[0012] Preferably, the fluid simulation software simulates the secondary atomization and breaking process of the hydroxy guar gum mixed solution, optimizes the percentage of each substance in the hydroxy guar gum mixed solution, the abrasive particle spacing, and the internal structure of the grinding wheel.

[0013] Preferably, the secondary atomization and breaking experiment of the hydroxy guar gum mixed solution measures and records the speed of the hydroxy guar gum droplet adhering to the grinding dust under different percentage of each substance in the hydroxy guar gum mixed solution and abrasive particle spacing, masters the optimal hydroxy guar gum droplet particle size and abrasive particle spacing, uses different internal structures of the grinding wheel for mixed lubricating liquid spraying experiments, observes and records the effect of different internal structures of the grinding wheel on the directional coverage of the surface area of the grinding wheel, and masters the optimal internal structure of the grinding wheel and the best mass percentage of the mixed solution.

[0014] Preferably, the temperature field of the grinding zone is simulated using ANSYS software, and the flow field of the grinding fluid in the grinding zone of the structured superhard abrasive adaptive grinding wheel is numerically simulated and analyzed using FLUENT software. This reveals the flow characteristics of the grinding fluid and its influence on lubrication and cooling performance, thereby optimizing the grinding wheel structure. Experimental studies on the grinding wheel are conducted, and the results are compared and analyzed with theoretical calculations and finite element simulations to optimize the theoretical and simulation models. Grinding force and grinding temperature are measured online using a three-dimensional force gauge and thermocouples, respectively, using a scanning electron microscope to observe the surface morphology, wheel clogging and wear, and chip morphology. Surface roughness and residual stress are measured using a roughness meter and X-ray diffractometer, respectively. Comparative analysis and research are conducted with ordinary grinding wheels in terms of grinding force, grinding temperature, surface roughness, micromorphology, residual stress, and wheel clogging and wear, to study the influence of structured flow channels on machining quality / accuracy during high-efficiency grinding.

[0015] Preferably, the hydroxyguanethol mixture flows along an arc-shaped inner channel at a certain angle, which helps to reduce the impact of the mixed lubricating oil on the channel and the grinding wheel body. The outer channel breaks through the air barrier layer on the surface of the grinding wheel, ensuring that the MoS2 nanoparticles fully fill the gaps between the grinding debris and abrasive grains in the grinding zone of the grinding wheel.

[0016] Preferably, the secondary atomization and fragmentation of the hydroxyguanethol solution ensures that a larger area of ​​the grinding wheel surface can be covered, thereby enabling a faster grinding debris removal speed.

[0017] Compared with existing technologies, the beneficial effects of this invention are as follows: This optimization method for high-speed precision grinding of C / C-SiC materials using superhard abrasives and grinding wheels innovatively proposes and systematically establishes the theory of high-speed precision grinding of C / C-SiC materials using superhard abrasive hardness-adaptive grinding wheels. It provides a theoretical basis and technical support for the application and promotion of high-speed precision grinding theory for single-layer and multilayer materials with anisotropic, brittle, and heterogeneous characteristics, such as carbon fiber reinforced silicon carbide ceramics and silicon carbide fiber reinforced silicon carbide ceramics. This invention solves the problems of various unavoidable surface defects on the workpiece surface during C / C-SiC material grinding, and the inability of overflowing grinding fluid to transfer heat out of the grinding zone in a timely manner. External micro-lubrication and nano-micro-lubrication reduce the effective utilization rate of the lubricating oil. This invention elucidates the grinding chip formation mechanism of C / C-SiC materials grinding with superhard abrasive hardness-adaptive grinding wheels through the grinding wheel surface mechanism of directional lubrication of MoS2 nanoparticles, revealing the influence of flow channel structure on the effective lubrication and chip removal effect of the lubricating fluid, thus achieving the effect of optimizing high-speed precision grinding of grinding wheels. Attached Figure Description

[0018] Figure 1 This is a flowchart of the optimized solution of the present invention. Detailed Implementation

[0019] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0020] Please refer to Figure 1 The present application provides a technical solution: a high-speed precision grinding optimization method of superhard abrasive and grinding wheel based on C / C-SiC material, comprising the following steps:

[0021] S1: The system establishes a structured theory of the hardness self-adaptive grinding wheel inner and outer flow channel structure of superhard abrasive, and reveals the influence law of the structural change of the flow channel on the mixed liquid flow, filling effect and barrier breaking effect;

[0022] S2: Through software simulation analysis and 3D printing of the grinding wheel inner flow channel simulation mixed liquid flow experiment, the fluid simulation software is used to simulate and analyze the secondary atomization and breaking process of the hydroxy guar gum mixed liquid, the percentage of each substance in the hydroxy guar gum mixed liquid, the abrasive particle spacing and the grinding wheel internal structure are optimized, and the relationship between the inner flow channel curve shape, cross section shape, inner flow channel taper change and the mixed liquid flow effect is analyzed;

[0023] S3: The influence law of the percentage of each substance in the hydroxy guar gum mixed liquid and the grinding wheel internal structure on the secondary atomization and breaking efficiency of the hydroxy guar gum mixed liquid is studied, and a corresponding mathematical model is established. The project is to simulate and analyze the process of twice atomization and breaking of the hydroxy guar gum mixed liquid after being sprayed out of the grinding wheel, optimize the percentage of each substance in the hydroxy guar gum mixed liquid and the grinding wheel internal structure, measure and record the speed of hydroxy guar gum droplet adhesion to abrasive dust under different conditions of the percentage of each substance in the hydroxy guar gum mixed liquid and the abrasive particle spacing, and master the best hydroxy guar gum droplet particle size and abrasive particle spacing. Different grinding wheel internal structures are used for mixed lubricating liquid spraying experiments, and the effects of different grinding wheel internal structures on the directional coverage of the grinding wheel surface area are observed and recorded, and the best grinding wheel internal structure and the best mass percentage of the mixed liquid are mastered;

[0024] S4: The atomization and breaking rate of the hydroxy guar gum mixed liquid is studied, the influence of the physical film formed by the MoS2 nanoparticles stretched on the friction surface under the grinding force on the grinding efficiency and the workpiece surface roughness is explored, the comparative experiments with traditional grinding are carried out, and the change and influence law of the grinding temperature, grinding force, grinding quality and grinding wheel wear of the superhard abrasive hardness self-adaptive grinding wheel are studied;

[0025] S5: Hydroxy guar gum solution is a typical non-Newtonian fluid, which has large viscosity and poor fluidity. Optimizing the structure parameters of the inner flow channel and realizing the uniform distribution of the inner flow channel around the grinding wheel shaft in the base and the effective breaking of the air barrier layer on the surface of the grinding wheel are the keys to reducing the kinetic energy loss caused by the mutual impact of hydroxy guar gum solution and the inner flow channel and breaking through the air barrier layer, and ensuring that the MoS2 nanoparticles fully fill the gap between the grinding dust and abrasive particles in the grinding area of the grinding wheel.

[0026] S6: The conditions, process and mechanism of secondary atomization of hydroxy guar gum mixed solution are studied, and the quantitative analysis of the influencing factors of secondary atomization is carried out to realize the controllable process of secondary atomization of hydroxy guar gum mixed solution.

[0027] S7: Force analysis of MoS2 nanoparticles under high speed and high pressure is carried out to explore the influence of the physical film formed by MoS2 nanoparticles under grinding force on the friction surface on the grinding efficiency, workpiece surface roughness and surface / subsurface damage.

[0028] The flow of hydroxy guar gum mixed solution along the arc-shaped inner flow channel at a certain angle is beneficial to reduce the impact of mixed lubricating oil on the flow channel and the grinding wheel body, and the outer flow channel breaks the air barrier layer on the surface of the grinding wheel to ensure that the MoS2 nanoparticles fully fill the gap between the grinding dust and abrasive particles in the grinding area of the grinding wheel.

[0029] Secondary atomization and fragmentation of hydroxy guar gum solution ensure that the grinding wheel surface can be covered with a larger area, so that the grinding dust removal speed can be faster.

[0030] Optimization principle, first, the fluid dynamics optimization method of the inner and outer flow channel structure of the superhard abrasive hardness adaptive grinding wheel is studied to determine the influence of the inner flow channel structure on the flow of mixed solution, the formation mechanism and breaking method of grinding air barrier layer and the establishment of laser preparation conditions of the outer flow channel structure of the grinding wheel, then the structure parameters of the inner flow channel of the supply system are determined, and the synergistic lubrication mechanism of the secondary atomization and fragmentation of guar gum mixed solution is studied, the synergistic lubrication mechanism of the molecular structure of nanoparticles, the influence of different mass fraction of nanoparticles on the grinding performance of the grinding wheel, the atomization mechanism of guar gum mixed solution, then the experimental conditions of superhard abrasive hardness adaptive grinding wheel high-speed precision grinding C / C-SiC material are determined, and the design parameters are optimized combined with the actual effect, the influence law of grinding on grinding force, grinding temperature and surface topography after grinding is summarized and supplemented, EDS, FTIR and XPS are used for composition detection, SEM, XRD, optical microscope and white light interferometer are used for morphology and damage detection, and temperature detector and force meter are used for monitoring the experiment.

[0031] The high-speed rotation of the grinding wheel causes relative motion of the air on its surface, forming an air barrier layer. This layer, with its inherent speed and pressure, effectively acts as a barrier, making it difficult for either external or internal grinding fluid to penetrate the wheel surface. This air barrier phenomenon is particularly pronounced in high-speed grinding. The surface of a high-speed rotating grinding wheel contains various rotating airflows, including circumferential, penetrating, internal, and radial flows. The higher the wheel speed, the thicker the air layer, and the greater the obstruction to the entry of grinding fluid into the grinding zone. However, the flow channels in the grinding layer generate a large amount of radial airflow on the surface of the grinding layer during wheel rotation. These airflows collide and rub against the tangential airflow (the main part of the air barrier layer), canceling each other out. Regarding the research on the self-lubricating mechanism and grinding performance of nanoparticle grinding wheels, the project team previously conducted grinding experiments on engineering ceramics using nanoparticle-lubricated diamond grinding wheels, studying the modification effect of nanoparticles and the lubrication release mechanism in the grinding zone. When nanoparticles are applied to grinding, their significantly higher thermal conductivity compared to ordinary grinding fluids results in high heat transfer efficiency, excellent cooling, and resistance to high pressure and high temperature. This allows them to withstand high temperatures and prevent melting during grinding wheel sintering. The lubrication mechanism includes: internal release – the grinding process inevitably involves friction between the workpiece and the bonding agent; nanoparticles are directly added to the bonding agent and, after friction, are released along with the bonding agent into the grinding zone; anti-wear and friction reduction – the near-spherical structure of MoS2 nanoparticles, after release, forms a lubricating film between the workpiece and diamond abrasive grains in the grinding zone, reducing the friction coefficient of the grinding wheel. Simultaneously, some grinding debris is carried away by the hydroxyguanol colloid, reducing the adhesion of abrasive grains to debris and preventing debris from clogging the grinding wheel pores, thus reducing wear; repair and polishing – after release, nanoparticles can fill the cavities and damaged areas of the grinding wheel, providing a certain degree of repair. Harder particles can also participate in friction with the diamond abrasive grains, equivalent to a polishing effect, reducing the surface roughness of the workpiece.

[0032] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for optimizing high-speed precision grinding based on C / C-SiC material superhard abrasive and grinding wheel, characterized in that, The method comprises the following steps: S1: the system establishes a superhard abrasive hardness adaptive grinding wheel inner and outer flow channel structure theory, and reveals the influence law of the structural change of the flow channel on the mixed liquid flow, filling effect and barrier breaking effect; S2: the relationship between the inner flow channel curve shape, cross section shape, inner flow channel taper change and the mixed liquid flow effect is analyzed through software simulation analysis and 3D printing grinding wheel inner flow channel simulation mixed liquid flow experiment; S3: the influence law of the percentage of each substance in the hydroxy guar gum mixed liquid and the internal structure of the grinding wheel on the secondary atomization breaking efficiency of the hydroxy guar gum mixed liquid is studied, and the corresponding mathematical model is established. The project is to simulate and analyze the process of the secondary atomization breaking of the hydroxy guar gum mixed liquid after being sprayed out of the grinding wheel, and optimize the percentage of each substance in the hydroxy guar gum mixed liquid and the internal structure of the grinding wheel; S4: the atomization breaking rate of the hydroxy guar gum mixed liquid is studied, the influence of the physical film formed by the MoS2 nanoparticles stretched on the friction surface under the grinding force on the grinding efficiency and the workpiece surface roughness is explored, the comparative experiment with the traditional grinding is carried out, and the change and influence law of the grinding temperature, grinding force, grinding quality and grinding wheel wear of the superhard abrasive hardness adaptive grinding wheel are studied; S5: the hydroxy guar gum solution is a typical non-Newtonian fluid, which has large viscosity and poor flowability. Optimizing the inner flow channel structure parameters and realizing the uniform distribution of the inner flow channel in the base around the grinding wheel shaft and the effective breaking of the outer flow channel on the air barrier layer of the grinding wheel are the keys to reducing the kinetic energy loss caused by the mutual impact of the hydroxy guar gum solution and the inner flow channel and breaking through the air barrier layer, and ensuring that the MoS2 nanoparticles fully fill the gap between the grinding dust and the abrasive particles in the grinding area of the grinding wheel; S6: the conditions, process and mechanism of the secondary atomization of the hydroxy guar gum mixed liquid are studied, the quantitative analysis of the influencing factors of the secondary atomization is carried out, and the secondary atomization process of the hydroxy guar gum mixed liquid is realized. S7: the stress analysis of the MoS2 nanoparticles under high speed and high pressure is carried out, and the influence of the physical film formed by the MoS2 nanoparticles stretched on the friction surface under the grinding force on the grinding efficiency, workpiece surface roughness and surface / subsurface damage is explored.

2. The method according to claim 1, wherein the C / C-SiC material based superhard abrasive and grinding wheel high speed precision grinding optimization method is characterized in that, The fluid simulation software simulates and analyzes the secondary atomization breaking process of the hydroxy guar gum mixed liquid, optimizes the percentage of each substance in the hydroxy guar gum mixed liquid, the abrasive particle spacing and the internal structure of the grinding wheel.

3. The method according to claim 2, wherein the C / C-SiC material based superhard abrasive and grinding wheel high speed precision grinding optimization method is characterized in that, The secondary atomization breaking experiment of the hydroxy guar gum mixed liquid measures and records the speed of the hydroxy guar gum droplet adhering to the grinding dust under different percentage of each substance in the hydroxy guar gum mixed liquid and abrasive particle spacing, masters the optimal hydroxy guar gum droplet particle size and abrasive particle spacing, uses different internal structures of the grinding wheel for mixed lubricating liquid spraying experiment, observes and records the effect of different internal structures of the grinding wheel on the directional coverage of the grinding wheel surface area, and masters the optimal internal structure of the grinding wheel and the best mass percentage of the mixed liquid.

4. The method according to claim 1, wherein the C / C-SiC material based superhard abrasive and grinding wheel high speed precision grinding optimization method is characterized in that, ANSYS software is used to simulate the temperature field of grinding zone, and FLUENT software is used to simulate the flow field of grinding fluid in the grinding zone of structured superhard abrasive grain hardness adaptive grinding wheel, so as to reveal the flow characteristics of the grinding fluid and its influence law on lubrication and cooling performance, and then optimize the grinding wheel structure. The experimental study on the grinding wheel is carried out, and the theoretical calculation results and the finite element simulation results are compared and analyzed, the theoretical model and the simulation model are optimized. Dynamic measurement technology three-way force meter and thermocouple are used to measure the grinding force and grinding temperature online. Scanning electron microscope is used to observe the grinding surface morphology, grinding wheel blockage and wear, and abrasive shape. Roughness meter and X-ray diffractometer are used to measure surface roughness and residual stress, respectively. The comparative analysis and research on grinding force, grinding temperature, grinding surface roughness, micro-morphology, residual stress and grinding wheel blockage and wear are carried out, and the influence law of structured flow channel on machining quality / machining precision in high-efficiency grinding process is studied.

5. The method according to claim 1, wherein the C / C-SiC material based superhard abrasive and grinding wheel high speed precision grinding optimization method is characterized in that, The hydroxy guar gum mixed solution flows along the arc-shaped inner flow channel at a certain angle, which is beneficial to reduce the impact of mixed lubricating oil on the flow channel and the grinding wheel body, the outer flow channel breaks the air barrier layer on the surface of the grinding wheel, and ensures that the MoS2 nanoparticles fully fill the gap between the abrasive and the abrasive in the grinding zone of the grinding wheel.

6. The method according to claim 1, wherein the C / C-SiC material based superhard abrasive and grinding wheel high speed precision grinding optimization method is characterized in that, The secondary atomization and fragmentation of the hydroxy guar gum solution ensure that the grinding wheel surface can be covered with a larger area, so that the abrasive removal speed can be faster.

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