The Experts below are selected from a list of 5574 Experts worldwide ranked by ideXlab platform
Xiaowei Zhang - One of the best experts on this subject based on the ideXlab platform.
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specific Grinding energy and surface roughness of nanoparticle jet minimum quantity lubrication in Grinding
Chinese Journal of Aeronautics, 2015Co-Authors: Dongkun Zhang, Yanbin Zhang, Dongzhou Jia, Xiaowei ZhangAbstract:Abstract Nanoparticles with the anti-wear and friction reducing features were applied as cooling lubricant in the Grinding fluid. Dry Grinding, flood Grinding, minimal quantity of lubrication (MQL), and nanoparticle jet MQL were used in the Grinding experiments. The specific Grinding energy of Dry Grinding, flood Grinding and MQL were 84, 29.8, 45.5 J/mm3, respectively. The specific Grinding energy significantly decreased to 32.7 J/mm3 in nanoparticle MQL. Compared with Dry Grinding, the surface roughness values of flood Grinding, MQL, and nanoparticle jet MQL were significantly reduced with the surface topography profile values reduced by 11%, 2.5%, and 10%, respectively, and the ten point height of microcosmic unflatness values reduced by 1.5%, 0.5%, and 1.3%, respectively. These results verified the satisfactory lubrication effects of nanoparticle MQL. MoS2, carbon nanotube (CNT), and ZrO2 nanoparticles were also added in the Grinding fluid of nanoparticle jet MQL to analyze their Grinding surface lubrication effects. The specific Grinding energy of MoS2 nanoparticle was only 32.7 J/mm3, which was 8.22% and 10.39% lower than those of the other two nanoparticles. Moreover, the surface roughness of workpiece was also smaller with MoS2 nanoparticle, which indicated its remarkable lubrication effects. Furthermore, the role of MoS2 particles in the Grinding surface lubrication at different nanoparticle volume concentrations was analyzed. MoS2 volume concentrations of 1%, 2%, and 3% were used. Experimental results revealed that the specific Grinding energy and the workpiece surface roughness initially increased and then decreased as MoS2 nanoparticle volume concentration increased. Satisfactory Grinding surface lubrication effects were obtained with 2% MoS2 nanoparticle volume concentration.
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experimental verification of nanoparticle jet minimum quantity lubrication effectiveness in Grinding
Journal of Nanoparticle Research, 2014Co-Authors: Dongzhou Jia, Dongkun Zhang, Yanbin Zhang, Xiaowei ZhangAbstract:In our experiment, K-P36 precision numerical control surface grinder was used for Dry Grinding, minimum quantity lubrication (MQL) Grinding, nanoparticle jet MQL Grinding, and traditional flood Grinding of hardened 45 steel. A three-dimensional dynamometer was used to measure Grinding force in the experiment. In this research, experiments were conducted to measure and calculate specific tangential Grinding force, frictional coefficient, and specific Grinding energy, thus verifying the lubrication performance of nanoparticles in surface Grinding. Findings present that compared with Dry Grinding, the specific tangential Grinding force of MQL Grinding, nanoparticle jet MQL Grinding, and flood Grinding decreased by 45.88, 62.34, and 69.33 %, respectively. Their frictional coefficient was reduced by 11.22, 29.21, and 32.18 %, and the specific Grinding energy declined by 45.89, 62.34, and 69.45 %, respectively. Nanoparticle jet MQL presented ideal lubrication effectiveness, which was attributed to the friction oil film with strong antifriction and anti-wear features formed by nanoparticles on the Grinding wheel/workpiece interface. Moreover, lubricating properties of nanoparticles of the same size (50 nm) but different types were verified through experimentation. In our experiment, ZrO2 nanoparticles, polycrystal diamond (PCD) nanoparticles, and MoS2 nanoparticles were used in the comparison of nanoparticle jet MQL Grinding. The experimental results manifest that MoS2 nanoparticles exhibited the optimal lubricating effectiveness, followed by PCD nanoparticles. Our research also integrated the properties of different nanoparticles to analyze the lubrication mechanisms of different nanoparticles. The experiment further verified the impact of nanoparticle concentration on the effectiveness of nanoparticle jet MQL in Grinding. The experimental results demonstrate that when the nanoparticle mass fraction was 6 %, the minimum specific tangential Grinding force, frictional coefficient, and specific Grinding energy were 1.285 N/mm, 0.382, and 57.825 J/mm3, respectively. When nanoparticle mass fraction was smaller than 6 %, lubrication effects of nanoparticle jet MQL increased with the rising nanoparticle mass fraction. When nanoparticle mass fraction was larger than 6 %, lubrication effects of nanoparticle jet MQL decreased with the rising nanoparticle mass fraction.
Dongzhou Jia - One of the best experts on this subject based on the ideXlab platform.
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specific Grinding energy and surface roughness of nanoparticle jet minimum quantity lubrication in Grinding
Chinese Journal of Aeronautics, 2015Co-Authors: Dongkun Zhang, Yanbin Zhang, Dongzhou Jia, Xiaowei ZhangAbstract:Abstract Nanoparticles with the anti-wear and friction reducing features were applied as cooling lubricant in the Grinding fluid. Dry Grinding, flood Grinding, minimal quantity of lubrication (MQL), and nanoparticle jet MQL were used in the Grinding experiments. The specific Grinding energy of Dry Grinding, flood Grinding and MQL were 84, 29.8, 45.5 J/mm3, respectively. The specific Grinding energy significantly decreased to 32.7 J/mm3 in nanoparticle MQL. Compared with Dry Grinding, the surface roughness values of flood Grinding, MQL, and nanoparticle jet MQL were significantly reduced with the surface topography profile values reduced by 11%, 2.5%, and 10%, respectively, and the ten point height of microcosmic unflatness values reduced by 1.5%, 0.5%, and 1.3%, respectively. These results verified the satisfactory lubrication effects of nanoparticle MQL. MoS2, carbon nanotube (CNT), and ZrO2 nanoparticles were also added in the Grinding fluid of nanoparticle jet MQL to analyze their Grinding surface lubrication effects. The specific Grinding energy of MoS2 nanoparticle was only 32.7 J/mm3, which was 8.22% and 10.39% lower than those of the other two nanoparticles. Moreover, the surface roughness of workpiece was also smaller with MoS2 nanoparticle, which indicated its remarkable lubrication effects. Furthermore, the role of MoS2 particles in the Grinding surface lubrication at different nanoparticle volume concentrations was analyzed. MoS2 volume concentrations of 1%, 2%, and 3% were used. Experimental results revealed that the specific Grinding energy and the workpiece surface roughness initially increased and then decreased as MoS2 nanoparticle volume concentration increased. Satisfactory Grinding surface lubrication effects were obtained with 2% MoS2 nanoparticle volume concentration.
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experimental verification of nanoparticle jet minimum quantity lubrication effectiveness in Grinding
Journal of Nanoparticle Research, 2014Co-Authors: Dongzhou Jia, Dongkun Zhang, Yanbin Zhang, Xiaowei ZhangAbstract:In our experiment, K-P36 precision numerical control surface grinder was used for Dry Grinding, minimum quantity lubrication (MQL) Grinding, nanoparticle jet MQL Grinding, and traditional flood Grinding of hardened 45 steel. A three-dimensional dynamometer was used to measure Grinding force in the experiment. In this research, experiments were conducted to measure and calculate specific tangential Grinding force, frictional coefficient, and specific Grinding energy, thus verifying the lubrication performance of nanoparticles in surface Grinding. Findings present that compared with Dry Grinding, the specific tangential Grinding force of MQL Grinding, nanoparticle jet MQL Grinding, and flood Grinding decreased by 45.88, 62.34, and 69.33 %, respectively. Their frictional coefficient was reduced by 11.22, 29.21, and 32.18 %, and the specific Grinding energy declined by 45.89, 62.34, and 69.45 %, respectively. Nanoparticle jet MQL presented ideal lubrication effectiveness, which was attributed to the friction oil film with strong antifriction and anti-wear features formed by nanoparticles on the Grinding wheel/workpiece interface. Moreover, lubricating properties of nanoparticles of the same size (50 nm) but different types were verified through experimentation. In our experiment, ZrO2 nanoparticles, polycrystal diamond (PCD) nanoparticles, and MoS2 nanoparticles were used in the comparison of nanoparticle jet MQL Grinding. The experimental results manifest that MoS2 nanoparticles exhibited the optimal lubricating effectiveness, followed by PCD nanoparticles. Our research also integrated the properties of different nanoparticles to analyze the lubrication mechanisms of different nanoparticles. The experiment further verified the impact of nanoparticle concentration on the effectiveness of nanoparticle jet MQL in Grinding. The experimental results demonstrate that when the nanoparticle mass fraction was 6 %, the minimum specific tangential Grinding force, frictional coefficient, and specific Grinding energy were 1.285 N/mm, 0.382, and 57.825 J/mm3, respectively. When nanoparticle mass fraction was smaller than 6 %, lubrication effects of nanoparticle jet MQL increased with the rising nanoparticle mass fraction. When nanoparticle mass fraction was larger than 6 %, lubrication effects of nanoparticle jet MQL decreased with the rising nanoparticle mass fraction.
Yanbin Zhang - One of the best experts on this subject based on the ideXlab platform.
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effect of friction coefficient on chip thickness models in ductile regime Grinding of zirconia ceramics
The International Journal of Advanced Manufacturing Technology, 2019Co-Authors: Min Yang, Chang He Li, Yanbin Zhang, Runze LiAbstract:The removal of material in the ductile regime while improving machining efficiency is currently the technical bottleneck in Grinding zirconia ceramics. Prediction models of minimum chip thickness (hmin) and ductile–brittle transition chip thickness (hd–b) were developed according to Grinding mechanism. Results showed that both hmin and hd–b decreased with increasing friction coefficient. Grinding experiments were carried out using the maximum undeformed chip thickness as the input parameter. Experimental results showed that the hmin value in Dry Grinding is 0.24 μm. Meanwhile, the hmin values under minimum quantity lubrication (MQL) and nanoparticle jet MQL (0.4, 0.8, 1.2, 1.6, and 2 vol.%) are 0.27, 0.34, 0.49, 0.65, 0.76, and 0.91 μm, respectively. Furthermore, the hd–b value in Dry Grinding is 0.8 μm, and the hd–b values under lubrication condition that corresponds to hmin are 1.79, 1.98, 2.15, 2.27, 2.39, and 2.59 μm, respectively. The experimental results show the same trend as that of the prediction model. The theoretical calculation is basically consistent with the measured values, with model errors of 7.9% and 6.3%, thereby verifying the accuracy of the chip thickness models.
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specific Grinding energy and surface roughness of nanoparticle jet minimum quantity lubrication in Grinding
Chinese Journal of Aeronautics, 2015Co-Authors: Dongkun Zhang, Yanbin Zhang, Dongzhou Jia, Xiaowei ZhangAbstract:Abstract Nanoparticles with the anti-wear and friction reducing features were applied as cooling lubricant in the Grinding fluid. Dry Grinding, flood Grinding, minimal quantity of lubrication (MQL), and nanoparticle jet MQL were used in the Grinding experiments. The specific Grinding energy of Dry Grinding, flood Grinding and MQL were 84, 29.8, 45.5 J/mm3, respectively. The specific Grinding energy significantly decreased to 32.7 J/mm3 in nanoparticle MQL. Compared with Dry Grinding, the surface roughness values of flood Grinding, MQL, and nanoparticle jet MQL were significantly reduced with the surface topography profile values reduced by 11%, 2.5%, and 10%, respectively, and the ten point height of microcosmic unflatness values reduced by 1.5%, 0.5%, and 1.3%, respectively. These results verified the satisfactory lubrication effects of nanoparticle MQL. MoS2, carbon nanotube (CNT), and ZrO2 nanoparticles were also added in the Grinding fluid of nanoparticle jet MQL to analyze their Grinding surface lubrication effects. The specific Grinding energy of MoS2 nanoparticle was only 32.7 J/mm3, which was 8.22% and 10.39% lower than those of the other two nanoparticles. Moreover, the surface roughness of workpiece was also smaller with MoS2 nanoparticle, which indicated its remarkable lubrication effects. Furthermore, the role of MoS2 particles in the Grinding surface lubrication at different nanoparticle volume concentrations was analyzed. MoS2 volume concentrations of 1%, 2%, and 3% were used. Experimental results revealed that the specific Grinding energy and the workpiece surface roughness initially increased and then decreased as MoS2 nanoparticle volume concentration increased. Satisfactory Grinding surface lubrication effects were obtained with 2% MoS2 nanoparticle volume concentration.
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experimental verification of nanoparticle jet minimum quantity lubrication effectiveness in Grinding
Journal of Nanoparticle Research, 2014Co-Authors: Dongzhou Jia, Dongkun Zhang, Yanbin Zhang, Xiaowei ZhangAbstract:In our experiment, K-P36 precision numerical control surface grinder was used for Dry Grinding, minimum quantity lubrication (MQL) Grinding, nanoparticle jet MQL Grinding, and traditional flood Grinding of hardened 45 steel. A three-dimensional dynamometer was used to measure Grinding force in the experiment. In this research, experiments were conducted to measure and calculate specific tangential Grinding force, frictional coefficient, and specific Grinding energy, thus verifying the lubrication performance of nanoparticles in surface Grinding. Findings present that compared with Dry Grinding, the specific tangential Grinding force of MQL Grinding, nanoparticle jet MQL Grinding, and flood Grinding decreased by 45.88, 62.34, and 69.33 %, respectively. Their frictional coefficient was reduced by 11.22, 29.21, and 32.18 %, and the specific Grinding energy declined by 45.89, 62.34, and 69.45 %, respectively. Nanoparticle jet MQL presented ideal lubrication effectiveness, which was attributed to the friction oil film with strong antifriction and anti-wear features formed by nanoparticles on the Grinding wheel/workpiece interface. Moreover, lubricating properties of nanoparticles of the same size (50 nm) but different types were verified through experimentation. In our experiment, ZrO2 nanoparticles, polycrystal diamond (PCD) nanoparticles, and MoS2 nanoparticles were used in the comparison of nanoparticle jet MQL Grinding. The experimental results manifest that MoS2 nanoparticles exhibited the optimal lubricating effectiveness, followed by PCD nanoparticles. Our research also integrated the properties of different nanoparticles to analyze the lubrication mechanisms of different nanoparticles. The experiment further verified the impact of nanoparticle concentration on the effectiveness of nanoparticle jet MQL in Grinding. The experimental results demonstrate that when the nanoparticle mass fraction was 6 %, the minimum specific tangential Grinding force, frictional coefficient, and specific Grinding energy were 1.285 N/mm, 0.382, and 57.825 J/mm3, respectively. When nanoparticle mass fraction was smaller than 6 %, lubrication effects of nanoparticle jet MQL increased with the rising nanoparticle mass fraction. When nanoparticle mass fraction was larger than 6 %, lubrication effects of nanoparticle jet MQL decreased with the rising nanoparticle mass fraction.
Taghi Tawakoli - One of the best experts on this subject based on the ideXlab platform.
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DEVELOPMENT OF A NOVEL METHOD FOR Dry Grinding OF SOFT STEEL
2020Co-Authors: Taghi Tawakoli, Bahman AzarhoushangAbstract:ABSTRACT Compared to other machining processes, Grinding involves high specific energy. This energy mainly transforms to heat which makes detrimental effects on surface integrity as well as tool wear. In Dry Grinding, as there is no cutting fluid to transmit generated heat in the contact zone, reducing Grinding energy and Grinding forces are crucial. Presented in this paper are some of the promising results of the systematic research work carried out by the authors in order to come closer to the goal of pure Dry Grinding. A new method to reduce the heat by superimposing ultrasonic vibrations on workpiece movement is presented. The obtained results show that the application of ultrasonic vibration can eliminate the thermal damage on the workpiece and decrease the Grinding forces considerably. A decrease of up to 60% of normal Grinding forces and up to 40% of tangential Grinding forces has been achieved
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an experimental investigation of the effects of workpiece and Grinding parameters on minimum quantity lubrication mql Grinding
International Journal of Machine Tools & Manufacture, 2009Co-Authors: Taghi Tawakoli, Sigrid Stockert, Ali Daneshi, Matthew J Hadad, M.h. Sadeghi, Abdolreza RasifardAbstract:Abstract Coolant is a term generally used to describe Grinding fluids used for cooling and lubricating in Grinding process. The main purposes of a Grinding fluid can be categorized into lubrication, cooling, transportation of chips, cleaning of the Grinding wheel and minimizing the corrosion. On the other hand, Grinding fluids have negative influences on the working environment in terms of the health of the machine operator, pollution and the possibility of explosion (for oil). Furthermore, the cost of the Grinding fluid, filtering and waste disposal of the metal working fluids is even higher than the tool cost and constitutes a great part of the total cost. Additionally, Grinding fluids can not effectively penetrate into the contact zone, are health hazard and their consumption must be restricted. Generally, compared to other machining processes, Grinding involves high specific energy. Major fraction of this energy is changed into heat, which makes harmful effect on the surface quality as well as the tool wear. Since there is no coolant lubricant to transfer the heat from the contact zone in Dry Grinding, surface damages are not preventable. Alternatives to current practices are getting more serious consideration in response to environmental and operational cost pressures. One attractive alternative is the minimum quantity lubrication (MQL) Grinding or the near Dry Grinding (NDG). In near Dry Grinding an air–oil mixture called an aerosol is fed into the wheel-work contact zone. Compared to Dry Grinding, MQL Grinding substantially enhances cutting performance in terms of increasing wheel life and improving the quality of the ground parts. In this research, the influences of workpiece hardness and Grinding parameters including wheel speed, feed rate and depth of cut have been studied on the basis of the Grinding forces and surface quality properties to develop optimum Grinding performances such as cooling, lubrication, high ecological and environmental safety.
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AN INNOVATIVE CONCEPT AND ITS EFFECTS ON WHEEL SURFACE TOPOGRAPHY IN Dry Grinding BY RESIN AND VITRIFIED BOND CBN WHEEL
Machining Science and Technology, 2008Co-Authors: Taghi Tawakoli, Mohammad RabieyAbstract:In the Dry Grinding process, as there is no coolant lubricant to transfer the heat from the contact zone, minimizing the Grinding specific energy and Grinding forces is a matter of importance. Some of the results of the systematic research works, based on a novel concept to make a step forward for pure Dry Grinding, are presented. The new concept is based on the fact that the optimisation of the chip formation reduces the friction and rubbing in the process. Such optimisation was achieved by a special conditioning process. The result showed a drastic reduction in Grinding forces and no burning or damages on the surface of workpiece using the novel method comparing to conventional wheel with the same material removal rate. A theoretical discussion is also presented to support the experimental results.
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influence of ultrasonic vibrations on Dry Grinding of soft steel
International Journal of Machine Tools & Manufacture, 2008Co-Authors: Taghi Tawakoli, Bahman AzarhoushangAbstract:Abstract Dry machining has been increasingly investigated in order to decrease the negative environmental impact of the cutting fluids, diminishing problems concerning waste disposal demand and also due to interest in decreasing manufacturing costs. However, generally in Dry Grinding, as there are no cutting fluids to transfer the heat from the contact zone, problems frequently occur in terms of high heat generation on Grinding wheel surface and workpiece surface, increasing the Grinding energy, wear of Grinding wheel, low material removal rate (regarding relatively low depth of cuts) as well as poor surface roughness compared to conventional Grinding. A recent and promising method to overcome these technological constraints is the use of ultrasonic assistance, where high-frequency and low amplitude vibrations are superimposed on the movement of the workpiece. The design of an ultrasonically vibrated workpiece holder and the experimental investigation of ultrasonically assisted Dry Grinding of 100Cr6 are presented. The surface roughness and Grinding forces of the ultrasonically and conventionally ground workpieces were measured and compared. The obtained results show that the application of ultrasonic vibration can eliminate the thermal damage on the workpiece, increase the G-ratio and decrease the Grinding forces considerably. A decrease of up to 60–70% of normal Grinding forces and up to 30–50% of tangential Grinding forces has been achieved.
Dongkun Zhang - One of the best experts on this subject based on the ideXlab platform.
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specific Grinding energy and surface roughness of nanoparticle jet minimum quantity lubrication in Grinding
Chinese Journal of Aeronautics, 2015Co-Authors: Dongkun Zhang, Yanbin Zhang, Dongzhou Jia, Xiaowei ZhangAbstract:Abstract Nanoparticles with the anti-wear and friction reducing features were applied as cooling lubricant in the Grinding fluid. Dry Grinding, flood Grinding, minimal quantity of lubrication (MQL), and nanoparticle jet MQL were used in the Grinding experiments. The specific Grinding energy of Dry Grinding, flood Grinding and MQL were 84, 29.8, 45.5 J/mm3, respectively. The specific Grinding energy significantly decreased to 32.7 J/mm3 in nanoparticle MQL. Compared with Dry Grinding, the surface roughness values of flood Grinding, MQL, and nanoparticle jet MQL were significantly reduced with the surface topography profile values reduced by 11%, 2.5%, and 10%, respectively, and the ten point height of microcosmic unflatness values reduced by 1.5%, 0.5%, and 1.3%, respectively. These results verified the satisfactory lubrication effects of nanoparticle MQL. MoS2, carbon nanotube (CNT), and ZrO2 nanoparticles were also added in the Grinding fluid of nanoparticle jet MQL to analyze their Grinding surface lubrication effects. The specific Grinding energy of MoS2 nanoparticle was only 32.7 J/mm3, which was 8.22% and 10.39% lower than those of the other two nanoparticles. Moreover, the surface roughness of workpiece was also smaller with MoS2 nanoparticle, which indicated its remarkable lubrication effects. Furthermore, the role of MoS2 particles in the Grinding surface lubrication at different nanoparticle volume concentrations was analyzed. MoS2 volume concentrations of 1%, 2%, and 3% were used. Experimental results revealed that the specific Grinding energy and the workpiece surface roughness initially increased and then decreased as MoS2 nanoparticle volume concentration increased. Satisfactory Grinding surface lubrication effects were obtained with 2% MoS2 nanoparticle volume concentration.
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experimental verification of nanoparticle jet minimum quantity lubrication effectiveness in Grinding
Journal of Nanoparticle Research, 2014Co-Authors: Dongzhou Jia, Dongkun Zhang, Yanbin Zhang, Xiaowei ZhangAbstract:In our experiment, K-P36 precision numerical control surface grinder was used for Dry Grinding, minimum quantity lubrication (MQL) Grinding, nanoparticle jet MQL Grinding, and traditional flood Grinding of hardened 45 steel. A three-dimensional dynamometer was used to measure Grinding force in the experiment. In this research, experiments were conducted to measure and calculate specific tangential Grinding force, frictional coefficient, and specific Grinding energy, thus verifying the lubrication performance of nanoparticles in surface Grinding. Findings present that compared with Dry Grinding, the specific tangential Grinding force of MQL Grinding, nanoparticle jet MQL Grinding, and flood Grinding decreased by 45.88, 62.34, and 69.33 %, respectively. Their frictional coefficient was reduced by 11.22, 29.21, and 32.18 %, and the specific Grinding energy declined by 45.89, 62.34, and 69.45 %, respectively. Nanoparticle jet MQL presented ideal lubrication effectiveness, which was attributed to the friction oil film with strong antifriction and anti-wear features formed by nanoparticles on the Grinding wheel/workpiece interface. Moreover, lubricating properties of nanoparticles of the same size (50 nm) but different types were verified through experimentation. In our experiment, ZrO2 nanoparticles, polycrystal diamond (PCD) nanoparticles, and MoS2 nanoparticles were used in the comparison of nanoparticle jet MQL Grinding. The experimental results manifest that MoS2 nanoparticles exhibited the optimal lubricating effectiveness, followed by PCD nanoparticles. Our research also integrated the properties of different nanoparticles to analyze the lubrication mechanisms of different nanoparticles. The experiment further verified the impact of nanoparticle concentration on the effectiveness of nanoparticle jet MQL in Grinding. The experimental results demonstrate that when the nanoparticle mass fraction was 6 %, the minimum specific tangential Grinding force, frictional coefficient, and specific Grinding energy were 1.285 N/mm, 0.382, and 57.825 J/mm3, respectively. When nanoparticle mass fraction was smaller than 6 %, lubrication effects of nanoparticle jet MQL increased with the rising nanoparticle mass fraction. When nanoparticle mass fraction was larger than 6 %, lubrication effects of nanoparticle jet MQL decreased with the rising nanoparticle mass fraction.
