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Riblet surface is a biomimetic surface that not only has the ability to reduce surface drag resistance of mechanical products in fluids, but also improves surface hydrophobicity. Therefore, studying its manufacturing technology has practical significance for solving its engineering applications. In order to grind the riblet surface on the cylindrical workpiece, an innovative hob-grinding strategy for reducing drag on cylindrical riblet surfaces using superhard grinding wheels with spiral abrasive pattern has been developed. To achieve this strategy, firstly, based on the analysis of the geometric topology features of the riblet surface, an engineered CBN grinding wheel with spiral arrangement of abrasive particles was designed based on the principle of gear hobbing machining. Then, the relationship between hob-grinding parameters and abrasive particle arrangement parameters on the parameters of the ground riblets was analyzed, and the process measures to increase the number of riblets on the cylindrical surface, the ratio of the height to spacing of riblets, and the impact on the surface geometry of the riblets were explored. Finally, the surface of the cylindrical riblet surface was ground through experiments, and under the conditions of this experiment, a riblet surface was obtained that its spacing, height, and ratio of the height-spacing were 93.85 µm, 14.65 µm, and 0.156, respectively. The research results indicate that using this strategy can grind the cylindrical riblet surface, and the proposed process strategy of increasing the number of riblets and the ratio of the height to spacing is feasible. [ABSTRACT FROM AUTHOR]

The surface residual stress of the parts has an important influence on their performance. The generation mechanism of surface residual stress in ultrasonic vibration-assisted grinding (UVAG) of bearing steel was investigated, and the correlation between processing parameters and residual stresses was obtained. Based on the ultrasonic vibration-assisted grinding force and thermal model and the flow stress model considering the initial material microstructure, the mechanical and thermal stresses of the material were calculated. Finally, the theoretical model of residual stress is established based on the yield theory and experimentally verified. High-speed ultrasonic aerostatic spindle for ultrasonic vibration-assisted grinding, change the inlet pressure to realize the ultrasonic amplitude and frequency adjustment, the experimental results show that the cutting direction and the vertical cutting direction of the residual stress test results and the model prediction results of the average relative error of 11.4% and 11.7%, and the rule of change is more consistent. Based on the experimental results, the influence pattern of process parameters on the experimental results was analyzed. The results show that the residual compressive stress on the surface of ultrasonic vibration-assisted grinding is directly proportional to the grinding depth, feed rate, and inlet pressure of pneumatic ultrasonic wave and inversely proportional to the linear speed of the grinding wheel. This study provides a theoretical basis for the analysis of UVAG residual stress and optimization of UVAG process parameters. [ABSTRACT FROM AUTHOR]

The intelligent monitoring of the grinding wheel wear state has the potential to enhance several key aspects of grinding operations, including wheel utilization, wheel dressing, grinding efficiency, grinding quality and so on. In this paper, it is proposed as an acoustic emission signal–based monitoring method of electroplated diamond grinding wheel wear state for C/SiC composite material groove grinding. Firstly, the full-life wear experiment of electroplated grinding wheel grinding C/SiC composites was carried out, and the connection between the acoustic emission signal and the wear state of the grinding wheel was established by frequency domain and time–frequency domain characteristics. Secondly, the time domain, frequency domain and time–frequency domain features of the signals in the stable grinding stage of C/SiC composites were extracted by wavelet packet method. Finally, based on the extracted features, the Extreme Learning Machine (ELM) was optimized by Mayfly Algorithm (MA) to realize online monitoring and intelligent recognition of grinding wheel wear. The results show that the sample classification accuracy of this method is 96.67%, which can effectively identify the different states of grinding wheel wear. [ABSTRACT FROM AUTHOR]

In this paper, a theoretical model for the grinding force of SiCp/Al composites was established. The model introduces a novel approach by integrating the SiC particle fracture force, the arc length of contact between the grinding wheel and workpiece, and the maximum undeformed chip thickness, all grounded in the principles of chip formation and friction forces. The accuracy of the grinding force theoretical model was validated through grinding experiments. Additionally, the effects of machining parameters and grinding wheel types on grinding force, surface roughness, and surface morphology were further investigated. The results indicate that as the grinding depth and feed speed increase, both the grinding force and surface roughness increase, resulting in poorer material surface quality. Conversely, when the grinding wheel speed increases, both the grinding force and surface roughness decrease, leading to better material surface quality. Compared to using electroplated diamond wheels, the use of resin bond wheel results in lower grinding force, lower surface roughness, and improved surface morphology, which proves that resin bond wheel has better grinding performance when grinding SiCp/Al composites with SiC volume fraction of 20%. This study indicates that the research facilitates the calculation of grinding forces in actual machining processes, as well as the selection of grinding parameters and types of grinding wheels. [ABSTRACT FROM AUTHOR]

Grinding could be used to enhance accuracy and quality of carbon fiber‐reinforced poly‐ether‐ether‐ketone (CF/PEEK) composites. However, the grinding mode, namely up‐grinding (UG) or down‐grinding (DG), is usually neglected while unbefitting grinding mode choice may cause inferior surface quality. To investigate effects of grinding modes on grinding performance of anisotropic CF/PEEK, grinding experiments in UG and DG were carried out under different fiber orientation angles θ. Experimental results indicated that maximum grinding temperatures and normal grinding forces in UG were lower than DG regardless of the abrasive grit sizes. Material removal mechanisms of CF/PEEK affected by grinding mode were revealed by analyzing morphologies of surface, chip and grinding wheel. When θ = 0°, the dominant mechanisms in DG were extrusion fracture and fiber deformation, while they were interface shear debonding and bending fracture in UG. When θ = 90°, the dominant mechanisms in DG included interface layer separation and bending fracture, while they were shear and extrusion fracture of well‐supported fibers in UG. Thus, UG was more favorable for material removal, obtaining lower surface roughness values, fewer machining defects and less wheel wear than DG. This study will provide technical guidance for high‐quality grinding of carbon fiber‐reinforced thermoplastic composites. Highlights: The effects of grinding modes (DG and UG) on the grinding performance of anisotropic CF/PEEK composites were investigated.Material removal mechanisms of CF/PEEK affected by grinding mode were revealed under different fiber orientation angles.The maximum grinding temperatures and normal grinding forces in UG were lower than DG.UG was more favorable for material removal in grinding, and could produce better ground surface quality than DG. [ABSTRACT FROM AUTHOR]

A sequential technique that combines wire electrical discharge machining (wire-EDM) and abrasive grinding on dedicated equipment improves the edge quality of boron-doped polycrystalline diamond (BD-PCD) cutting tools. In this study, we focus on material removal mechanisms during BD-PCD machining and surface graphitization caused by wire-EDM thermal damage. Surface topography is used to distinguish ductile- and brittle-regime grinding in tool production. Resin-bonded diamond wheels outperform electroplated diamond wheels in abrasive grinding owing to their self-sharpening capabilities. The experimental results show that BD-PCD tools have higher mechanical properties and performance than standard PCD tools. Maximum edge chipping on BD-PCD surfaces depends on the depth of cut and grinding speed. Microgrinding experiments on BK7 glass reveal that the recommended tool manufacturing approach, which merges wire-EDM and abrasive grinding, results in high-quality surfaces free of microcracks and achieves a surface roughness of 6 nm Sa. Abrasion on the flank face and chipping on the periphery are the main wear patterns on grinding tools. In this study, we improve our understanding of BD-PCD microcutter production, focusing on parameter management for optimal surface quality, edge integrity, and tool performance. We emphasize the necessity of choosing the right grinding wheel to achieve the necessary surface and subsurface quality when making microcutting tools. Raman spectroscopy results are used to explain thermal deterioration when diamond grains turn into graphite at high manufacturing temperatures. We address the challenges of producing high-quality microcutting tools and offer insights into improving BDPCD tool performance and edge quality. [ABSTRACT FROM AUTHOR]

The fabrication of high-precision and high-performance profile rollers represents the main challenge of utilizing profile rollers as dressers to condition conventional grinding wheels. This results in high demands for an efficient process to manufacture profile rollers (form dressing wheels). Conventionally, diamond profile rollers have been produced through infiltration or negative electroplating methods. Nevertheless, these manufacturing methods suffer significant drawbacks, including extended production times and substantial costs. This study presents an innovative approach to fabricating diamond profile rollers using Wire Electrical Discharge Conditioning (WEDC). The WED-Conditioning emerges as an effective alternative to profile metal-bonded rotary diamond dressing tools. This innovative method leads to the production of diamond profile rollers in significantly shorter timeframes and at a more economical cost compared to the conventional manufacturing method with comparable quality. The research delves into the influence of profile roller specifications and conditioning strategies on the achievable profile accuracy and topography of the profile rollers. Also, the wear behavior of the WEDC-conditioned profile roller over long-term conditioning of conventional grinding wheels was studied. The findings highlight the significant contribution of the appropriate selection of WEDC strategies to the profile accuracy, with the potential to achieve profile accuracies comparable with conventional profile rollers. As well, grain size emerges as the primary determinant of achievable profile accuracy for profile rollers. The findings of this study could provide insights into optimizing the manufacturing process for super abrasive diamond profile rollers, thereby enabling their widespread use in the grinding industry. [ABSTRACT FROM AUTHOR]

Large shaft grinding processes are required to generate multiple quality indices with good consistency, such as profile dimension accuracy, surface roughness, and optical glossiness. Generating profiles for large shafts in the grinding process requires the grinding wheels to move transversely under the desired path, which includes rough grinding, semi-finish grinding, finish grinding, and spark-out grinding stages, and each grinding stage needs to go through multiple passes under different process parameters. Therefore, the design and selection of process parameters for each grinding stage is always challenging to meet both quality and efficiency requirements. In this study, a multi-objective optimization method for transverse profile grinding processes of large shafts is developed. In the proposed method, multiple grinding quality indices and grinding efficiency are taken as optimization objectives, and grinding surface quality, grinding depth, and grinder machining performance are taken as constraints. By utilizing the dynamic factor improvement strategy and the adaptive grid density improvement strategy, an improved particle swarm algorithm is developed to optimize the grinding process parameters. The grinding dimensional error compensation method and the surface quality consistency control method are integrated into the improved particle swarm algorithm to realize the accurate prediction of grinding dimensional accuracy and surface quality. Based on the proposed method, the optimized grinding process can be obtained, and the effectiveness of the method is verified by grinding experiments. [ABSTRACT FROM AUTHOR]

A large amount of grinding heat is generated during the high-efficiency grinding process, which causes workpiece burnout. Although the utilization of a significant quantity of coolant can lower grinding temperature, it inevitably leads to environmental pollution and damages the health of operators. To reduce coolant usage, it is worth considering reducing the grinding temperature by enhancing the thermal performance of grinding wheels. In this study, a new type of phase change heat storage grinding wheel (PCHS grinding wheel) with a high heat transfer coefficient and large heat capacity is developed utilizing the boiling heat transfer principle and heat storage technology, whose structure and working principle are explained. In addition, a visual device was made to simulate the internal heat transfer and heat storage process of PCHS grinding wheels, and the effects of heat flux, injection amount of working fluid, heat dissipation conditions, and heat capacity on the boiling heat transfer coefficient, start-up time of working fluid entering the boiling heat transfer state, and grinding temperature control are analyzed. Eventually, a comparative experiment of dry grinding 45 steel was carried out. Results show that the boiling heat transfer coefficient of PCHS grinding wheels is in the range of 1000–7000 W/m2·°C, the start-up time is 5–8 s, and increasing the heat capacity of grinding wheels can effectively slow down the heating rate. Besides, the grinding temperature is reduced by 22% compared with the maximum temperature of 375 °C when using traditional grinding wheels, and the heat transfer coefficient is increased by 2–3 times, which shows that improving the thermal performance of grinding wheels has significant advantages in reducing grinding temperature. [ABSTRACT FROM AUTHOR]

Surface grinding is a widely employed finishing process in industrial sectors dedicated to achieve desired Surface characteristics of components. This study experimentally investigates the impact of the grinding parameters pertaining to the surface characteristics of Inconel 800, which is a nickel-iron-chromium alloy extensively used in high-temperature applications. Various commercially available grinding wheels were employed to grind Inconel800 under different grinding conditions. The ground surfaces were comprehensively analyzed using surface roughness measurements, Three-dimensional profilometry, optical microscopy, findings from XRD and SEM reveal that grinding parameters and wheel characteristics significantly impact the surface texture, topographical features, residual stress, and surface morphology of the machined nickel alloy.. The insights from this investigation contribute to the understanding of the grinding behavior of nickel-based superalloys and provide a basis for optimizing the grinding process for enhanced surface integrity. The findings are valuable for industries dealing with the machining of high-performance nickel alloy components. [ABSTRACT FROM AUTHOR]

The state of a grinding wheel directly affects the surface quality of the workpiece. The monitoring of grinding wheel wear state can allow one to efficiently identify grinding wheel wear information and to timely and effectively trim the grinding wheel. At present, on-line monitoring technology using specific sensor signals can detect abnormal grinding wheel wear in a timely manner. However, due to the non-linearity and complexity of the grinding wheel wear process, as well as the interference and noise of the sensor signal, the accuracy and reliability of on-line monitoring technology still need to be improved. In this paper, an intelligent monitoring system based on multi-sensor fusion is established, and this system can be used for precise grinding wheel wear monitoring. The proposed system focuses on titanium alloy, a typical difficult-to-process aerospace material, and addresses the issue of low on-line monitoring accuracy found in traditional single-sensor systems. Additionally, a multi-eigenvalue fusion algorithm based on an improved support vector machine (SVM) is proposed. In this study, the mean square value of the wavelet packet decomposition coefficient of the acoustic emission signal, the grinding force ratio of the force signal, and the effective value of the vibration signal were taken as inputs for the improved support vector machine, and the recognition strategy was adjusted using the entropy weight evaluation method. A high-precision grinding machine was used to carry out multiple sets of grinding wheel wear experiments. After being processed by the multi-sensor integrated precision grinding wheel wear intelligent monitoring system, the collected signals can accurately reflect the grinding wheel wear state, and the monitoring accuracy can reach more than 92%. [ABSTRACT FROM AUTHOR]

Ultra-precision machining has higher requirements for the performance of abrasive tools, but the traditional grinding wheel has some problems such as irregular grain arrangement, limited chip space, and high grinding temperature. Therefore, a structured grinding wheel suitable for ultra-precision machining is proposed. In this study, the laser cladding method and ultrasonic vibration technology were combined to study the preparation process of a structured grinding wheel. Firstly, the quality evaluation system of the printing layer was established, and the shape coefficient and dilution rate were used to evaluate the laser cladding quality. The effects of laser power, sweep speed, powder feeding speed, and ultrasonic power on the shape coefficient and dilution rate of the printing layer were analyzed by single-factor experiments. The level range of each factor in the orthogonal experiment was established to optimize the process parameters. The surface morphology was observed, and the influence of ultrasonic vibration on the morphology was analyzed. The structured grinding wheel was prepared according to the optimized parameters. [ABSTRACT FROM AUTHOR]

Resin bond grinding wheels are the most common grinding tools in the industry. Until now, all research on the additive manufacturing of resin bond grinding wheels has focused on commercially available acrylate resin. However, using a phenol-based bond to print resin-bond grinding wheels has been challenging for researchers and industries. In this study, a photo-curable phenol resin bond grinding wheel was introduced for the first time, offering advantages such as lower cost, high thermal resistance, and good mechanical properties. To enhance the grinding performance of the printed wheels, various additives, such as copper, glass fiber, and carbon fiber, were incorporated into the composition. Different on-machine and out-of-machine measurements, such as force, tool wear, dimensional accuracy, and optical microscopy measurements, were conducted to investigate the grinding performance of the printed wheels. The results demonstrate that printed grinding wheels have strong potential in grinding applications, which was more prominent for the bond reinforced by glass fibers, providing improved mechanical properties (up to 50%), wear resistance (up to 75%), and higher dimensional accuracy (up to 11%). [ABSTRACT FROM AUTHOR]

Copyright of Journal of South China University of Technology (Natural Science Edition) is the property of South China University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the problems of grinding wheel wear during high-speed cylindrical grinding, communication delays, and slow response during data acquisition, processing, and system operation, an intelligent online monitoring technology frame for CNC manufacturing units is proposed, incorporating a real-time-perception grinding mechanism and a cloud-edge device. Based on the grinding data and grinding wheel wear mechanism, a monitoring model using multi-sensor information fusion is constructed to assess the grinding wheel wear state. In addition, edge data acquisition and online monitoring software have been developed to improve the speed of data transmission and processing. Finally, based on the proposed framework, a cloud-edge device collaborative intelligent monitoring system for assessing grinding wheel wear during high-speed cylindrical grinding of bearing rings is constructed. It improves the grinding quality and efficiency, reduces the grinding cost, and incorporates remote control functionality. [ABSTRACT FROM AUTHOR]

During the axial modification in helical gear form grinding, the contact line between the grinding wheel and the gear constantly changes, and the additional radial motion can cause a "tooth surface twist" phenomenon. An optimization method for tooth surface twist error was proposed to address this. Based on the gear meshing principles, a mathematical model for axial modification in form grinding was established to solve for the instantaneous contact lines at various positions on the actual modified tooth surface. By analyzing the influence of the grinding wheel installation angle on the axial modification contact line, an optimization model was constructed to reduce the twist of the transverse profile, reduce the twist of the flank profile, reduce the helix deviation, and improve the form grinding efficiency. The practical implications of this research are significant, as the Particle Swarm Optimization (PSO) algorithm was employed to optimize the form grinding parameters, leading to a method that effectively reduced tooth surface twist error and improved the form grinding accuracy of the modified tooth surface. [ABSTRACT FROM AUTHOR]

Due to their high hardness at elevated temperatures and chemical stability, alumina-based ceramic cutting tools have been successfully applied in the machining of ferrous materials, especially quenched and tempered steels. Their low fracture toughness, however, makes it difficult to finish them by grinding, as cracks and defects can occur. In addition, its application in machining processes demands appropriate edge preparation to avoid tool failure. Within this context, the paper aims to demonstrate the applicability of an experimental Al2O3 + MgO ceramic cutting insert in hard turning. For this, grinding tests were performed to determine the most appropriate conditions to improve its surface and edge quality. The effects of cutting and feed speeds, grinding wheel bonding material, and abrasive grain size were investigated. Moreover, different cutting-edge geometries were prepared in this tool material and tested in turning a hardened AISI 4140 steel (50 HRC) to determine their performance regarding tool life and workpiece roughness. The results demonstrated that a finer grinding wheel (D15) combined with high cutting (60 m/s) and feed (10 mm/min) speeds leads to the lowest surface roughness and edge chipping. In addition, both symmetric (Κ = 1) and asymmetric (Κ = 2) edge roundings led to higher tool lives in hard turning in comparison to a single chamfered tool, as they contributed to better load distribution in the cutting region. The paper provides information for the manufacture and application of alumina-based ceramic cutting inserts in the metalworking industry, as it disseminates good manufacturing practices and recommendations for appropriate cutting-edge geometry. [ABSTRACT FROM AUTHOR]

The complexity of composite grinding movement, the variety of machining features and available grinding wheels, and the changing working conditions pose a challenge to the rapid programming of safe and efficient composite grinding procedure. The procedure optimisation plays an important role in solving this difficult problem. Therefore, a procedure optimisation method is proposed for composite grinding based on a Digital Twin (DT) system, which takes procedure time as optimisation objective to achieve high efficiency and ensures process rationality and safety by constructing corresponding constraint conditions. Moreover, the actual working conditions mapped into the DT system, such as workpiece parameters, machining requirements, grinding wheel parameters and status, machine tool motion position, and so on, are obtained to update the parameters involved in the optimisation model. And thus, the proposed method has the ability to timely find the optimal procedure under changing working conditions. In addition, a combination algorithm based on genetic algorithm (GA) and dynamic programming is proposed, which greatly reduces the search space of GA and realises the two-class co-optimisation of grinding wheel selection and procedure. Finally, the case study verifies the effectiveness of the proposed method to reduce procedure time and the dynamic response ability to changing working conditions. [ABSTRACT FROM AUTHOR]

Grinding is an ultra-precision machining technology. The grinding force and grinding heat emerge as pivotal physical parameters. Excessive grinding temperature can engender unwarranted thermal damage to the processed material. In cup grinding wheel face grinding, employing a singular abrasive grain discrete heat source method enables a more precise establishment of the face grinding temperature field. Cross tracks of abrasive exist widely in cup grinding wheel, and the influence of cross-point temperature should be considered in order to accurately establish the grinding temperature field model. Thus, a single-grain discrete point heat source superposition temperature field analytical model was established. Through trochoid feed scratch experiments, the variation law of thermal effect of cross-points under different cutting depth is verified. The experimental findings reveal conspicuous changes in cutting force and cutting heat at the entry and exit positions of the scratch intersection region. Moreover, the abrasive grain scratch sustains more severe damage compared to other regions. The energy change caused by the impact effect is the key factor leading to the temperature change at the intersection. The energy lost at the entrance of the intersection position is close to the energy of the impact effect. With the increase of the cutting depth, the ratio of the two tends to converge towards 1, ranging from 0.868 to 0.932 to 0.965. The error between the theoretical model and experimental verification is less than 5%, indicating the single-particle discrete heat source superposition temperature field model can well characterize the grinding surface temperature field caused by cross-point effect, which lays a foundation for the grinding heat theory based on trochoid model. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Diamond & Abrasives Engineering is the property of Zhengzhou Research Institute for Abrasives & Grinding and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Diamond & Abrasives Engineering is the property of Zhengzhou Research Institute for Abrasives & Grinding and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Diamond & Abrasives Engineering is the property of Zhengzhou Research Institute for Abrasives & Grinding and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work discusses challenges in conventional grinding wheels: heat-induced tool wear and workpiece thermal damage. While textured abrasive wheels improve heat dissipation, the current surface-only methods, such as those based on laser and machining, have high renewal costs. The proposed manufacturing technology introduces an innovative 3D cooling channel structure throughout the wheel, enabling various channel geometries for specific abrasive wheel applications. The production steps were designed to accommodate the conventional pressing and sintering phases. During pressing, a 3D organic structure was included in the green body. A drying cycle eliminated all present fluids, and a sintering one burnt away the structure, revealing channels in the final product. Key parameters, such as binder type/content and heating rate, were optimized for reproducibility and scalability. Wear tests showed a huge efficiency increase (>100%) in performance and durability compared of this system to conventional wheels. Hexagonal channel structures decreased the wear rates by 64%, displaying superior wear resistance. Comprehensive CFD simulations evaluated the coolant flow through the cooling channels. This new design methodology for three-dimensionally structured grinding wheels innovates the operation configuration by delivering the coolant directly where it is needed. It allows for increasing the overall efficiency by optimizing cooling, reducing tool wear, and enhancing manufacturing precision. This 3D channel structure eliminates the need for reconditioning, thus lowering the operation costs. [ABSTRACT FROM AUTHOR]

Polymeric resins are becoming increasingly popular in medical and engineering applications due to their properties, such as their low weight, high strength, corrosion resistance, non-allergenicity, and extended service life. The grinding process is used to convert these materials into desired products, offering high accuracy and surface quality. However, grinding generates significant heat, which can potentially degrade the material. This study investigates the grinding of acrylic-based resins, specifically focusing on the interplay between the grind zone temperature and surface finish. The low glass transition temperature (57 °C) of the acrylic necessitates the precise control of the grinding parameters (spindle speed, feed rate, depth of cut, and grinding wheel grain size), to maintain a low temperature and achieve high-quality machining. Thermal imaging and thermocouples were employed to measure the grind zone temperature under various grinding conditions. This study investigates the influence of four parameters: spindle speed, feed rate, depth of cut, and grinding wheel grain size. The best surface finish (Ra: 2.5 µm) was obtained by using a finer-grained (80/Ø 0.18 mm) grinding wheel, combined with slightly adjusted parameters (spindle speed: 11.57 m/s, feed rate: 0.406 mm/rev, depth of cut: 1.00 mm), albeit with a slightly higher grind zone temperature (~54 °C). This study highlighted the importance of balancing the grind zone temperature and surface finish for the optimal grinding of acrylic-based resins. Further, this research finds that by carefully controlling the grinding parameters, it is possible to achieve both a high surface quality and prevent material degradation. The research findings could be highly valuable for optimizing the grinding process for various medical and engineering applications. [ABSTRACT FROM AUTHOR]

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ductile iron is a heterogeneous material. The presence of spherical graphite and a hard and brittle structure makes the surface of the workpiece easily form pits and crack defects under harsh grinding conditions, which seriously affects the service life and service performance of the workpiece. The new assisted grinding process based on the electroplastic effect is expected to avoid the surface defects of ductile iron. By comparing the surface roughness and microstructure of conventional grinding and electroplastic-assisted grinding, the superiority of electroplastic-assisted grinding surface quality is confirmed. Further discussion is presented on the impact of grinding parameters on the workpiece's surface quality under the same electrical parameters. The results show that the sensitivity of surface roughness to grinding parameters from strong to weak is grinding wheel speed, feed speed and grinding depth. The optimal combination of grinding parameters is determined as a grinding wheel speed of 30 m/s, a feed speed of 0.5 m/min and a grinding depth of 10 μm. [ABSTRACT FROM AUTHOR]

The precision machining of Ti-6Al-4V (TC4) micro-channels remains a challenge due to the poor surface integrity and limited tool life. Ultrasonic vibration-assisted grinding (UVAG) is a promising technique that is being employed to enhance the achieved quality of Ti-6Al-4V micro-channels. Taking the wheel's wear and the springback of the workpiece into consideration, a new kinematic simulation model for the 3D surface generation process is first developed, and the material removal mechanism under different ultrasonic parameters during UVAG of Ti-6Al-4V is investigated based on the calculated grit-cutting trajectory and ground surface topography. Comparing the simulated and experimental results, it is found that the built surface topography prediction model can successfully capture the obtained surface characteristics of Ti-6Al-4V by CG and UVAG process. The condition for intermittent machining in UVAG is obtained by establishing the mathematical relation between grinding and ultrasonic parameters. Therefore, the model developed in this paper can be applied to predict surface roughness and optimize the UVAG process of Ti-6Al-4V. [ABSTRACT FROM AUTHOR]

Bionic structured grinding wheels have gained significant attention in precision grinding because they perform particularly well in improving the overall performance of grinding. However, there is a lack of theoretical research on the workpiece ground surface morphology by bionic structured grinding wheels. This problem has hindered the further development of bionic grinding wheel technology. This paper presents a mathematical modeling study of the ground surface of our designed combinatorial bionic structured grinding wheel (CBSGW), which combines phyllotaxis-arrangement and fish-scale elements. The effect of the combinatorial bionic structure on the surface roughness and surface morphology of the workpiece was investigated by analyzing the number of effective cutting edges involved in grinding. In this paper, a finite element model of multi-particle grinding is developed to study the stress-strain occurring in the workpiece material during the grinding process. The results of the grinding experiments verified the correctness of the calculated results of the mathematical model. The effect of machining parameters on the surface roughness of the machined workpiece is also explained. It also represents an advancement in the grinding theory of bionic structured grinding wheels, providing a solid theoretical basis for their further development. [ABSTRACT FROM AUTHOR]

Bearings are an important part of the aviation equipment. The working accuracy, performance, service life, and reliability of bearings directly determine the performance of the aviation equipment. The manufacturing accuracy has been gradually improved with the ELID (electrolytic in-process dressing) grinding technology. The grinding-wheel wear has been an unavoidable problem in the ELID grinding of ball-bearing raceways. The ELID grinding-wheel profile needs to be promptly reshaped as soon as its profile deviation is greater than the allowable range. So far, few literatures are concerned about the precision evolution of the grinding-wheel profile under ELID conditions. There are no ready-made standards or instructions for the nonstandard ultra-precision bearings. Even the quality consistency is hard to be achieved. In this research, it aims to balance the service life of the grinding wheel and grinding accuracy. A comprehensively evaluating model is established, which includes two submodels. One is the contour-error submodel for assessing the groove raceway of bearings, in which the precision evolution principles are developed to work as the basis for this submodel. The other is the radial-wear rate submodel for evaluating the precision evolution of the ELID grinding wheel. In submodel 2, a special device is designed and established for the in situ monitoring of the radial-wear rate of the ELID grinding wheel under ELID conditions. It expands the application field of the precision-evolution principle for manufacturing the nonstandard bearings with ultrahigh precision. The rationality of the comprehensively evaluating model is verified by a group of optimal parameters derived from the five-factor-four-level orthogonal experiments. The conclusions can provide an important reference for balancing the wear of the grinding wheel and the grinding accuracy. [ABSTRACT FROM AUTHOR]

An optimization design was carried out based on a back propagation (BP) neural network and a genetic algorithm (GA) to improve the stiffness and accuracy of the self-developed MGK6030 five-axis tool grinding machine. First, finite element analysis was carried out on the whole grinding machine based on ANSYS Workbench, and the key parts were found to be the grinding wheel headstock, B axle box body, and column. Sensitivity analysis was carried out after the model parameterization, and ten parameters, which affect the quality, maximum deformation, and first-order mode, were obtained. These parameters were used as input variables. A total of 235 sets of sample data were obtained by using the optimal overall performance of the grinder for the target (large first-order natural frequency, small deformation, and mass). The BP neural network was then used to fit the nonlinear coupling relationship between the input and the output. Thereafter, the optimization function of the GA was used to perform multi-objective optimization in the specified range. Finally, the parameters are verified by software simulation and prototype test. Results showed that the maximum deformation of the optimized machine tool is reduced by 21%, and the first four order natural frequencies are increased by 6.36%, 9%, 6.4%, and 2.84%. The positioning accuracies of the linear axis and rotary axis are increased by 22% and 21%, respectively, which demonstrates the effectiveness of the optimization scheme and provides theoretical and technical support for similar optimization problems. [ABSTRACT FROM AUTHOR]

High-precision dressing of coarse-grained arc-shaped diamond grinding wheels is one of the research hotspots in the field of precision grinding. However, the dressing of coarse-grained grinding wheels is very difficult. The electrical discharge aided grinding (EDAG) dressing technology has been innovatively proposed, which can achieve high efficiency and precision dressing of coarse-grained arc-shaped diamond grinding wheels. The material removal mechanism of the EDAG dressing method has been thoroughly analyzed. Orthogonal experiments were designed to analyze the influence of process parameters on dressing efficiency and tool loss, the rough dressing was carried out to improve dressing efficiency, and the precision dressing was carried out to improve dressing accuracy. For the concave and convex arc-shaped grinding wheel dressing with the design radius of 3 mm, the radius size errors of concave and convex arcs after rough dressing are 4.43% and 2.69%, respectively. The PV value of profile accuracy is 54.34 μm. The radius size errors of concave and convex arcs after precision dressing are 0.17% and 0.053%, respectively. The PV value of profile accuracy is 17.28 μm. Finally, the radius size errors of concave and convex arc-shaped obtained by grinding silicon carbide ceramic specimens are 0.24% and 0.045%, respectively. The surface roughness of workpiece is up to 463 nm. Thus, the EDAG dressing technology can achieve high-precision dressing of arc-shaped coarse-grained diamond grinding wheels. [ABSTRACT FROM AUTHOR]

Due to its exceptional mechanical properties, 18CrNiMo7-6 alloy steel is one of the preferred materials for producing critical components, such as high-speed heavy-duty gearboxes. To study the relationship between cylindrical grinding parameters (e.g., workpiece speed, wheel speed, and grinding depth) and responses (i.e., grinding force, temperature, and surface residual stress), dimensional analysis and finite element simulation of cylindrical grinding were performed in this paper. A mathematical model for predicting the grinding force and residual stress of cylindrical grinding was proposed, and numerical and experimental verifications of cylindrical 18CrNiMo7-6 alloy steel were carried out. The numerical verification results showed that the maximum relative errors of the model for predicting the grinding force and residual stress were 7.9% and 11.2%, respectively. The experimental results revealed that the maximum absolute errors were 1.31 N and 33.7 MPa, respectively. To consider the simplification between finite element simulation and experiments, a modified model was proposed, with the errors of 5.4% and 8.6% for grinding force and residual stress, respectively. The results of this study indicate that the proposed model can guide practical grinding operations and help optimize machining parameters, improve production efficiency, and achieve high-quality machining results. [ABSTRACT FROM AUTHOR]

Zirconia ceramic (ZrO2) has been widely utilized in industrial areas for its excellent physical and mechanical properties. It is essential to study the grinding effect and the parameters optimization, to achieve high efficiency and precision grinding. The response surface experiments of ZrO2 grinding are designed, where the grinding wheel speed, workpiece speed, and grinding depth are selected as the three grinding parameters. The experiment is carried out on a surface grinding machine with a diamond grinding wheel. The four response surface quadratic regression models are built for the grinding force, the surface roughness, the surface breakage rate, and the subsurface damage depth. Combined with the four regression models and the maximum undeformed chip thickness model, the effect of grinding parameters on the grinding results is comprehensively assessed. For the integrated minimum of the machining time and the four grinding results, the multi-objective optimization is carried out on the grinding parameters. The correctness of the optimization model is verified by experiment. [ABSTRACT FROM AUTHOR]

To distinguish the grinding performance of the multidirectional (MD) and unidirectional (UD) carbon fiber‐reinforced thermoplastic (CFRTP) composites, MD and UD carbon fiber‐reinforced poly‐etherether‐ketone (CF/PEEK) composites were employed in this study. Different ply stacking sequences and process parameters were set for grinding experiments. Subsequently, the surface morphologies and roughness were observed and measured. Experimental results indicated that the variations of grinding forces with grinding parameters of MD‐CF/PEEK and UD‐CF/PEEK were consistent. However, the heat transfer mechanism and the effects of grinding parameters on the maximum grinding temperatures were different between the two composites. The grinding forces and temperatures of MD‐CF/PEEK were slightly lower than UD‐CF/PEEK, and MD‐CF/PEEK reached better surface quality under the same parameters, indicating that the grinding performance of MD‐CF/PEEK was not the simple superposition of UD‐CF/PEEK. In addition, the chip formation and material removal mechanism of CF/PEEK were investigated. The grinding performance of MD‐CF/PEEK was primarily dependent on the θ elements of laminate while the grinding performance of UD‐CF/PEEK was closely related to the fiber orientation angles during grinding. This study established a more in‐depth understanding into the grinding performance of MD‐CF/PEEK and provided technical guidance for high‐quality grinding of CFRTP. Highlights: The grinding performance of the multidirectional (MD) and unidirectional (UD) carbon fiber‐reinforced poly‐etherether‐ketone (CF/PEEK) is compared.The grinding forces and temperatures of MD‐CF/PEEK are slightly lower than that of UD‐CF/PEEK, and the MD‐CF/PEEK reach a better surface quality under the same grinding parameters.The grinding performance of MD‐CF/PEEK is primarily dependent on the θ elements of laminate, and the change of layering order is not a critical factor.The grinding performance of UD‐CF/PEEK is closely related to the fiber orientation angles during the grinding process.The surface quality of MD‐CFRTP can be effectively improved by reducing the grinding depth and feed speed, and increasing the grinding wheel speed. [ABSTRACT FROM AUTHOR]

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SiCf/SiC composites have gained significant attention as a highly promising material for engine thermal structures, primarily due to their remarkable high-temperature mechanical properties, along with their low density and outstanding resistance to oxidation. In the development background of sustainable and green manufacturing technology, how to realize the low-damage machining of SiCf/SiC ceramic matrix composites is an urgent problem to be solved. In this study, the effect of dry grinding, flood grinding, minimum quantity lubrication, and nanofluid minimum quantity lubrication (MoS2 and carbon nanotubes (CNTs)) on the surface quality at different grinding depths was thoroughly investigated. The results showed that the surface quality of grinding was better, and the grinding force was lower under carbon nanotube nanofluid lubrication compared to the other four lubrication methods. Compared with dry grinding, carbon nanotube nanofluid lubrication significantly reduced the grinding temperature by 79.3%, 86.1%, and 83.5% at grinding depths of 0.2 mm, 0.4 mm, and 0.6 mm, respectively. In addition, the stable lubrication film formed by NMQL-CNTs can significantly increase the service life of grinding wheels, improve surface quality, and help obtain a surface morphology with fewer surface defects. Although brittle removal was observed in different lubrication methods, NMQL-CNTs significantly reduced surface damage due to their "filling effect" and excellent friction reduction. This study provides theoretical guidance for the low-damage processing of SiCf/SiC composites. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) is ideal for making powerful, high-frequency chips for 5 G and electric vehicles due to its wide band gap and resistance to high voltage. However, its powerful chemical bond strength and extreme hardness make it difficult for die separation in the post-wafer process. A hybrid process technology is proposed, where die scribing is performed on SiC wafer using a femtosecond pulsed laser-assisted ablation. The extremely short energy pulses forced the ablation of traces of SiC at extreme speed, breaking chemical bonds and thereby reducing strength and hardness for easy high-speed cutting along the scribed lanes with a polycrystalline diamond wheel. The experiment showed that the average stage current dropped from 0.90 A to 0.45 A and kerf chipping ratio from 11.7 to 4.1 during die separation, proving that the process removed materials along the separation lanes using a wheel tool at low grinding force, creating separation lanes of outstanding straightness and minimal kerf chippings and SiC dies of high integrity. Furthermore, thanks to the on-line rotational machining and dressing of the wheel tool, the blunt diamond abrasive cutting edge could be redressed to expose chip pockets of appropriate depth and protruding grinding edges with a favorable negative rake angle. The established grinding regime utilizing a pressure-grinding force in cutting and material removal reduced cracking at the SiC surface. In this paper, the laser energy density, scanning speed, number of ablations, focus position, as well as the speed, feed-rate and grinding depth of the wheel tool are also discussed in detail. [ABSTRACT FROM AUTHOR]

In this study, the thermal model of the creep feed deep profile (CFDP) grinding process of a small-module gear was established regarding the spatial interaction between the workpiece and grinding wheel, as well as the thermal boundary and the energy partition. A 3D dynamic finite element simulation of small-module gear CFDP grinding was carried out by utilizing the element birth and death technique. The validation experiments aided the specially designed thermocouples in that the grinding temperature on both sides of the tooth groove could be measured simultaneously, which demonstrated a satisfactory agreement with the experimental findings. The average difference was approximately 10%, which proved the feasibility and accuracy of the simulation. The effects of three possible geometric structures for both sides of the tooth groove being processed on the grinding temperature distribution were discussed based on the validated finite element model. This study is expected to enhance comprehension of the temperature distribution in the CFDP grinding of a small-module gear and offer recommendations for optimizing the process parameters in the precision machining of a small-module gear. [ABSTRACT FROM AUTHOR]

Climate actions have been gaining prominence in discussions about the industrial future due to the need to reduce the amounts of residual pollutants in manufacturing processes. Although the grinding process is widely applied in the industry for its finishing capabilities and dimensional and geometric precision, it is significantly polluting and detrimental to workers' health. This is attributed to the quantity of mineral oil used in conventional flood lubrication-cooling systems. With these demands in mind, this work proposes alternative methods by comparing the performance of the alumina grinding wheel with the conventional method of lubrication-cooling using MQL, with and without the WCJ auxiliary system, and distinguishing the direction angles of the air jet in the cylindrical grinding process. The workpieces are made of VP50 steel, and the analyzed output parameters include surface roughness (Ra), with confocal microscopy used on the workpiece surface, roundness error, diametrical wheel wear, G-ratio, grinding power, tangential cutting force, and cost and pollution analysis. [ABSTRACT FROM AUTHOR]

Copyright of Diamond & Abrasives Engineering is the property of Zhengzhou Research Institute for Abrasives & Grinding and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Diamond & Abrasives Engineering is the property of Zhengzhou Research Institute for Abrasives & Grinding and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The drive at the center of gravity (DCG) concept-based twin-ball-screw drive mechanism (TBSDM) is vital in automated factories for its robustness and reliability. However, changes in the worktable mass or position result in changes in the center of gravity (CG), significantly affecting the system's dynamic properties. In this regard, this paper introduces a novel analytical model using improved receptance coupling to analyze vibrations in four modes. A mathematical framework for the twin TBSDM is generated, and the effect of changing the worktable position–mass on each mode is examined. The applicability of the proposed method is verified based on dynamic experiments that were carried out on a TBSDM of a CNC grinding wheel machine tool. After thoroughly analyzing the experimental and theoretical results, it is revealed that changing the worktable position primarily influences the rotational and axial vibrations of the twin ball screw (TBS). Furthermore, changes in the worktable mass significantly affect the coupling vibration among the TBSs and rotors or bearings. Moreover, in terms of performance, the variances between the theoretical and experimental natural frequencies are consistently below 5%. Thus, the proposed method is promising for the improvement of the modeling and analysis of the TBSDM. [ABSTRACT FROM AUTHOR]

SiC ceramics are typically hard and brittle materials. Serious surface/subsurface damage occurs during the grinding process due to the poor self-sharpening ability of monocrystalline diamond grits. Nevertheless, recent findings have demonstrated that porous diamond grits can achieve high-efficiency and low-damage machining. However, research on the removal mechanism of porous diamond grit while grinding SiC ceramic materials is still in the bottleneck stage. A discrete element simulation model of the porous diamond grit while grinding SiC ceramics was established to optimize the grinding parameters (e.g., grinding wheel speed, undeformed chip thickness) and pore parameters (e.g., cutting edge density) of the porous diamond grit. The influence of these above parameters on the removal and damage of SiC ceramics was explored from a microscopic perspective, comparing with monocrystalline diamond grit. The results show that porous diamond grits cause less damage to SiC ceramics and have better grinding performance than monocrystalline diamond grits. In addition, the optimal cutting edge density and undeformed chip thickness should be controlled at 1–3 and 1–2 um, respectively, and the grinding wheel speed should be greater than 80 m/s. The research results lay a scientific foundation for the efficient and low-damage grinding of hard and brittle materials represented by SiC ceramics, exhibiting theoretical significance and practical value. [ABSTRACT FROM AUTHOR]

Grinding tools can be used for over 90% of their lifetime, but most practical production tools are replaced between 50 and 80%. Accurate tool condition monitoring, which can monitor the quality of grinding tools, can improve product quality and reduce costs. The transfer learning technique can solve the data distribution and data deficiency issues of deep learning methods, enabling precise tool condition prediction in a grinding system. However, selecting the optimal pre-trained model is crucial for enhancing transfer learning performance due to the relationship between the source and target domains and the negative transfer problem. To address this issue, an encoding metric-based model selection technique was developed that accurately reflects the time series similarity between the remaining useful life (RUL) of the grinding tool and the encoding value and features between the pre-trained model and target data. Encoding metrics that reflect the critical characteristics of transfer learning, such as the target label, data, and pre-trained model, were computed to assess the pre-trained models directly. The target RUL and the extracted encoding values from the target input data and pre-trained models were compared using measurements and correlation to evaluate how closely they matched. The encoding selection method demonstrated superiority over the current source selection criteria, with encoding-based root mean square error (RMSE), mean absolute error, and dynamic time warping showing a high association with the approach (over a Pearson correlation coefficient of 0.66). Furthermore, the method was independent of the quantity and quality of the sources, making it robust for various datasets. The experimental dataset was used to validate the pre-trained model's encoding RMSE selection method, and the method was verified with a strong correlation (Pearson correlation coefficient of 0.79). In conclusion, the proposed encoding metric-based model selection technique can improve both the efficiency and intelligence of the machining process in terms of both quantity (exchange periods) and quality of grinding tools. Accurate tool condition monitoring enabled by this technique can lead to enhanced product quality and reduced costs. [ABSTRACT FROM AUTHOR]

The grinding process of transmission gear with worm grinding wheel usually relies on the manual parameter setting by experienced engineers, but the reliability and validity are quite hard to control due to many grinding factors that affect the surface quality (e.g. structure, size, and materials of gear, heat treatment process, surface accuracy requirements). Therefore, it is necessary to set up a decision system for assisting engineers with designing the process plan efficiently and reasonably. A modified model of the revision method based on the radial basis function (RBF) neural network and case-based reasoning (CBR) considering evaluation index was proposed in this paper. A similar case retrieval mainly relies on the soft likelihood function considering a compound evaluation index model, where the score value of each new case execution test is converted into the corresponding index to achieve effective case storage. Process solutions for similar cases that perform better will be recommended from the case database by means of CBR. These candidates can be revised systematically based on a self-learning model. A modified RBF neural network trained by the existing cases will apply the learned experience to revise solution in part or in whole, which utilizes a self-filtering attribute method based on the correlation coefficient matrix so as to gain the primary attributes. In the case of the grinding gear with worm grinding wheel, the applicability of this technology was demonstrated. A decision-making system applying this method was developed by using.Net framework4.0 and SQL Server. Consequently, the technique can quickly generate a feasible process plan for specific gear. [ABSTRACT FROM AUTHOR]

The ordered grinding wheel can achieve reasonable control of abrasive grain arrangement and grain distance, thus improving the chip space of the grinding wheel and reducing abrasive grain redundancy. In this paper, the design method of the ordered diamond grinding wheel is explored. The grinding model of the ordered diamond grinding wheel was established, and grinding experiments were conducted to verify the accuracy of the model. The results show that the model can reflect the influence law of each arrangement parameter on the surface roughness, but the model needs to consider more situations to interpret the actual grinding process more accurately. It is found that the surface roughness increases with the increase of the grain distance and decreases with the increase of the grain distribution angle. When the grain distribution angle is π/4, the abrasive grain rows may be horizontally aligned along the circumferential direction, resulting in a significant reduction in the number of effective abrasive grains and a significant increase in surface roughness. An ordered diamond grinding wheel was prepared for grinding experiments, and it was found that the surface roughness of the ground titanium alloy was higher than the simulation result. The results of this study provide theoretical guidance and reference for the design and preparation of the ordered grinding wheel. [ABSTRACT FROM AUTHOR]

In the study, the authors investigated the effects of picosecond laser ablation on the surface topographies of MONEL® alloy 400, used in the manufacturing of marine equipment components (such as pumps, valves, fixtures and fasteners). The experimental methodology involved preparing the material through grinding, polishing, and cleaning before subjecting it to picosecond laser ablation using specific parameters. The laser processing was carried out to create square ablated cavities on the alloy surface. The impact of the laser treatment on the surface condition of the alloy was assessed through profilometry analysis. The results provide insights into the surface topographies of the laser-treated MONEL® alloy 400 samples, offering valuable information for potential applications in marine industries [ABSTRACT FROM AUTHOR]