Diamond Grinding Wheel Research Articles

Analysis and optimization of abrasive waterjet dressing parameters for surface texturing of diamond grinding wheels

With the development of ultra-precision machining technology, the grinding performance of diamond grinding wheels has put forward higher requirements. In this study, a new method of dressing diamond grinding wheels using abrasive waterjet (AWJ) technology is proposed to address the issues of workpiece damage and wheel clogging that occur when grinding difficult-to-machine materials with conventional diamond grinding wheels. The main process parameters were determined based on the theoretical model for dressing diamond grinding wheels using AWJ. The response surface methodology (RSM) and the backpropagation artificial neural network (BP-ANN) were employed to establish regression models between process parameters and microgroove characteristics. A comparison was performed to evaluate the prediction performance of both RSM and BP-ANN. The results indicated that both approaches BP-ANN and RSM are powerful tools for predicting microgroove characteristics. This work provides theoretical guidance for texturing diamond wheels surface.

Crack characteristics of pulsed laser brazed diamond grinding wheel

Experiments on pulsed laser brazing of diamond grinding wheels were carried out in this paper. The crack characteristics and residual stress of brazed layer were detected and evaluated. The influence laws of pulse width, frequency, diamond mixing ratio, number of stacked layers, powder thickness and preheating temperature on crack characteristics were investigated. The pulsed laser characteristic coefficients (peak pulse power density/pulse interval time) and the correlation law between thermal stresses and cracks are discussed. The results show that the pulse width and frequency of the pulsed laser affect the cracking rate by varying the energy input and the time between pulses. The existence of a suitable value for the pulse characteristic coefficient corresponding to pulse width and frequency corresponds to a lower cracking rate. Thermal stress variations due to changes in process conditions at different diamond percentages, number of stacked layers, and preheating temperatures are the main causes of crack rate variations. Cracking is not only affected by thermal stresses, but also by the quality of the formed surface when pulsed laser brazing diamond to nickel–chromium alloy brazing material. For example, the main reason for the variation in cracking rate is the change in the morphology of the molded surface due to the variation in the thickness of the powder spread at different variations in the thickness of the powder spread.

A study of diamond grinding wheel wear condition monitoring based on acoustic emission signals

A study of diamond grinding wheel wear condition monitoring based on acoustic emission signals

Optimal design and performance evaluation of grinding wheels with triply periodic minimal surface lattice structure

High-performance grinding wheels are critical tools for precision surface generation. In precision grinding processes, the coolant supply at the wheel-workpiece interface is critical for reducing grinding temperature and detrimental friction. For better lubrication and chip removal performance, the cavities or pores need to be generated throughout the grinding wheel. The ideal morphology of pores in grinding wheels should be inter-connected and capable of providing sufficient coolant. Conventional grinding wheel design and fabrication methods can only passively generate closed circular pores by using pore-forming agents. Increasing the percentage of pores in this way generally leads to an uncontrollable reduction in mechanical strength, while the closed pores are insufficient in cooling performance. In this paper, the grinding wheels with triply periodic minimal surface lattice structure are designed and fabricated, which achieves the regulable and inter-connected internal structure of grinding wheels. Meanwhile, to balance the relationship between the structural properties and performance indicators of porous grinding wheels, an optimal design method for the porous structure of grinding wheels is proposed. Finally, the grinding performance of the novel grinding wheels in comparison to electroplated diamond grinding wheels is investigated in terms of grinding force, specific grinding energy and ground surface roughness.

Electrochemical Weakening Material Strength for Accelerated Thinning of Silicon Carbide Substrates

This paper presents a novel approach to expedite the thinning of silicon carbide (SiC) substrates, a crucial step in enhancing material performance and extending chip longevity by reducing volume resistivity. The traditional methods of SiC substrate thinning, such as diamond wheel grinding and plasma etching, have inherent limitations, including the risk of wafer breakage and high processing costs. In response to these challenges, we propose an innovative technique involving the electrochemical etching attenuation of SiC strength, offering a cost-effective and efficient solution.In this study, we employed an electrochemical method to initially weaken the SiC substrate from the surface to a defined depth, followed by fine-tuning its thickness using a conventional diamond grinding wheel. Remarkably, our results demonstrate that SiC substrates subjected to electrochemical treatment exhibit well-structured lattices free from residual stresses. This novel approach not only reduces the risk of wafer breakage but also enhances the material's integrity (Figure 1).To gain deeper insights into the effects of electrochemistry on SiC material strength, advanced characterization techniques, including scanning electron microscopy, were employed. Our findings reveal that the electrochemically treated SiC surface exhibits a sponge-like morphology, with a cross-sectional profile showcasing prominent columnar structures (Figure 2). This sponge-like structure is attributed to the removal of silicon atoms during anodization, affirming the effectiveness of electrochemical methods in rapidly attenuating the material strength of SiC substrates, thereby facilitating their efficient thinning through grinding without compromising substrate integrity.In summary, this research highlights the potential of electrochemical methodologies for the initial weakening of SiC substrates, leading to accelerated and cost-effective thinning processes. This breakthrough not only expedites SiC substrate thinning but also contributes significantly to the advancement of SiC substrate thinning and grinding techniques, promising substantial benefits for future semiconductor device fabrication. Figure 1

Parametric design and performance evaluation of TPMS porous vitrified bond diamond grinding wheel using digital light processing

Porous vitrified bond diamond grinding wheels are commonly used for grinding hard and brittle materials. However, uneven pore distribution and low porosity affect the grinding performance of the wheel significantly. In this study, three types of triply periodic minimal surface porous vitrified bond diamond grinding wheels—Gyroid, Diamond, and Lidinoid–were prepared through parametric designing and digital light processing 3D printing. The grinding wheel achieved a uniform distribution and an interconnected pore structure. The key to high-performance grinding wheel via stereolithography 3D printing lies in the preparation of the slurry with high solid loading, low viscosity and uniform stability. Hence, the effect of surface modifiers on the slurry, along with the effect of sintering temperature and the microscopic and mechanical properties, was investigated. By grinding the SiC ceramics, the material removal rate, grinding temperature, and surface roughness were compared to those achieved using a conventional solid-structure grinding wheel. The results show that the slurry with the highest solid content of 80 wt% (58 vol%) and viscosity of 4.21 Pa s (30 s−1) can be prepared using surface-modified particles. The diamond grinding wheel sintered at 680 °C exhibits the best comprehensive performance. A grinding wheel prepared using stereolithography 3D printing can achieve better surface roughness and lower the grinding temperature.

Recent Patent on Diamond Grinding Wheel Dressing

Diamond grinding wheels, particularly the advanced single-layer brazed variants, are indispensable for efficiently machining hard materials such as ceramics. Effective dressing is crucial, as it optimizes the wheel's isotropy and rotational accuracy, thereby ensuring precise machining. The selection of dressing tools and the conditions under which they operate significantly influence wheel quality, impacting key factors including topography, sharpness, wear rate, grinding forces, temperatures, and the surface integrity of the machined part. Consequently, the development of costeffective, high-performance dressing devices is of paramount importance. Furthermore, to provide a comprehensive review of representative patents in diamond grinding wheel dressing and to analyze the unique features, advantages, and disadvantages of various diamond grinding wheel dressing methods. Differentiating by method, diamond grinding wheel dressing devices fall into mechanical, memorable, and compound categories. Each patent addresses traditional device drawbacks with unique innovations, highlighting technical gaps and development needs in respective fields. Contemporary research in diamond dressing technology predominantly revolves around optimizing mechanical dressing methodologies. This focus is complemented by pioneering advancements in the architectural design and performance augmentation of dressing apparatuses, aiming to elevate efficiency and precision in various industrial applications. Specialized dressing techniques have resulted in many superior devices that are now widely utilized. Modern dressing devices are characterized by their high accuracy, efficiency, and performance. The mechanical dressing method enjoys the broadest applicability, proving highly effective for dressing diamond grinding wheels. Specialized dressing methods, on the other hand, offer superior dressing effects and the distinct advantage of contactless operation, thereby extending the service life of diamond grinding wheels. The composite dressing approach, merging the best attributes of mechanical and specialized methods, presents significant potential. Though currently underrepresented in terms of available devices, this field is expected to see considerable development and expansion in the future.

Grinding performance of MgF2 ceramics using biomimetic shark fin grinding wheels with different structure parameters

In the field of precision machining, with the popularity of brittle and hard materials such as infrared windows, it has become difficult for conventional diamond grinding wheels to effectively perform high-quality machining. The structuring of traditional diamond grinding wheels using a pulsed laser is a key technology to effectively improve the grinding quality of grinding wheels. In this paper, three new shark fin diamond grinding wheels (SFSGW) with different slot widths are designed based on the excellent drag-reducing and channelizing properties of shark dorsal fins. The grinding performance of traditional grinding wheels (USGW) and SFSGW on magnesium fluoride ceramics was compared. The effects of SFSGW on the surface quality, surface roughness and wheel damage of the workpiece were investigated. The results showed that the surface roughness of ceramics after grinding by SFSGW was reduced by 22.15 % compared with USGW, and the surface quality was better. Proper construction increases the material removal rate of the wheel and improves the wear resistance and service life of the wheel.

Influence of grain concentrations gradients on the profiling behaviour of bronze bonded diamond grinding wheels

In this work, diamond grinding wheels are first manufactured with two different metallic bonds. These are a ductile and a brittle bronze. Two differently graded (varied grain concentration) grinding wheels and two non-graded reference grinding wheels are manufactured in each case. The mechanical properties of these are then determined. Subsequently, a method is presented that enables the profiling of graded grinding wheels. For this purpose, the grinding wheels are profiled with SiC rolls using different profiling parameters. The profile accuracy after profiling is analysed using contour profiles in polyurethane. In addition, the dressing ratio and the process duration of profiling are measured. These parameters are used to determine the economic efficiency of the profiling process. Finally, this provides a bond-dependent profiling process that can economically and reproducibly generate a target contour on a grinding tool.

Material Removal Mechanism of SiC Ceramic by Porous Diamond Grinding Wheel Using Discrete Element Simulation.

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.

Ultra-low damage processing of silicon wafer with an innovative and optimized nonwoven grind-polishing wheel

Silicon is essential to the production of integrated circuits and optical components. Grinding is a commonly used method of silicon surface machining, but it often leads to surface and subsurface damage. These damages need to be removed by subsequent processes, typically through polishing. The surface quality generated by grinding directly impacts the cost of polishing. To enhance the quality of the grinding surface and reduce the time and cost of polishing, a grind-polishing wheel with a different structure from the conventional diamond wheel was developed. This wheel utilized ultrafine zirconia with grit size of 200 nm as abrasives and nonwoven as substrate to support the abrasives. Furthermore, to optimize the wheel and achieve better grinding performance, various wheels with different abrasive mass fractions and elastic moduli were fabricated and grinding experiments were conducted. The surface integrity of processed silicon and the material removal rate (MRR) were used to compare the grinding performance of the various wheels. After optimization, the MRR of the grind-polishing wheel reaches its peak at 0.81 μm/min. The silicon wafer ground with the grind-polishing wheel exhibited a surface roughness Sa of 0.51 nm and a subsurface damage depth of 74 nm, which is close to the effect of chemical mechanical polishing processing. Compared to conventional diamond grinding wheel (mesh size of #5000), the optimized grind-polishing wheel is better suited for semi-fine finishing and can significantly reduce the cost and time of polishing.

Modeling and validation of the grinding morphology of ordered diamond grinding wheel

Modeling and validation of the grinding morphology of ordered diamond grinding wheel

Investigation of the Machined Surface Integrity of WC-High-Entropy Alloy Cemented Carbide

A fine-grained WC-15wt%Al0.5CoCrFeNi cemented carbide was prepared through a vacuum and gas pressure sintering. For achieving high surface integrity, diamond wheel grinding serves as the primary molding process for the machining of WC cemented carbide. To reveal the influence of grinding on the surface integrity of fine-grained WC-HEA cemented carbide, studies were conducted on grinding force, surface microstructure, surface roughness, residual stress, microhardness, and bending strength. The morphological analysis of the ground surface indicated a transition in the material removal mechanism of WC-HEA cemented carbide from ductile removal to brittle removal, with brittle removal becoming predominant as the depth of grinding increases. With the increasing depth of grinding, the grinding force increases, and the grinding force increases while the surface roughness decreases. Correspondingly, there is an improvement in both hardness and bending strength. Additionally, grinding induces high residual compressive stress on the surface, with a maximum compressive stress of 1795 MPa. The bending strength of the material is found to be dependent on the residual stress.

Laser dressing of fine-grained metal-bonded diamond grinding wheels with concave surface

Electrical Discharge Dressing (EDD) of fine-grained metal-bonded diamond grinding wheel is the most recognized processing method in the industry at present. In this paper, the processing method of nanosecond pulse laser dressing of fine-grained metal-bonded diamond wheel with concave surface was proposed. The main components of the heat affected zone on the sub-surface of the wheel after laser dressing were proposed. The influence of the laser circumferential overlap ratio (OC) on the size of the heat affected zone of the metal-bonded material was systematically studied, and the formation mechanism of the angle error of the wheel with different influence degree of two kinds of effects was explained as the result of the change of laser energy density. The results demonstrated that with the increase of OC, the burn degree and sub-surface quality of the wheel surface became worse. The optimal laser circumferential overlap ratio OC was 30 %. It was found that the laser energy was continuously lost with the decrease of the angle, and better dressing effect could be obtained by deflecting the laser. The fine-grained metal diamond wheel with concave surface dressed by the deflection nanosecond pulse laser had better surface quality and profile accuracy, but there were certain metamorphic layers. Compared with the static single-section image detection (SSID), the grinding graphite plate detection (GGPD) more reflected the actual situation, and the maximum angle, arc radius and height deviation values of the 600# concave trapezoidal contour were 0.281°, 0.0049 mm, 0.0299 mm, respectively; The maximum angle, arc radius and height deviation values of the 1000# concave V-shaped contour were 0.293°, 0.0029 mm and 0.0255 mm, respectively.

Performance of patterned single-layer diamond grinding wheel in grinding of Al-SiCP composites with large infeed

Performance of patterned single-layer diamond grinding wheel in grinding of Al-SiCP composites with large infeed

Enhancing the grinding performance of RB-SiC ceramic using abrasive water jet dressed diamond grinding wheels

Reaction-bonded silicon carbide (RB-SiC) is regarded as difficult-to-machine ceramic materials with extremely high strength and hardness. The work focuses on the grinding performance evaluation of RB-SiC ground by the dressing diamond grinding wheel with AWJ. Orthogonal experiments studied the influence of processing parameters on grinding force and 3D surface roughness, with the response surface method identifying optimal parameters. Explanation of the ground surface topography and 3D surface roughness in a comprehensive manner shows that an erosion of the bonding material by micro-cutting but diamond grains are being pulled out rather than cut. Results reflect a correlation between surface topography and diamond wheel dressing. The results are of great significance for future formulating an appropriate grinding process to machine RB-SiC ceramics.

Laser-assisted surface grinding of innovative superhard SiC-bonded diamond (DSiC) materials

Silicon carbide (SiC)-bonded diamond materials, comprising approximately 50% diamond by volume, represent innovative composites with exceptional mechanical and thermal properties, including high hardness, wear and corrosion resistance, and elevated thermal conductivity. Despite these advantageous properties, the machining of these composites presents formidable challenges due to their extremely high hardness. Grinding with diamond tools is commonly employed among the limited viable machining methods. However, the efficiency of this process is hindered by high grinding forces, elevated temperatures, and significantly high tool wear. Additionally, the surface integrity, form, and dimensional accuracy of the workpiece are compromised by the effects of tool wear and high cutting forces. To address these technological constraints in the grinding of SiC-bonded diamond materials, a laser-assisted grinding process has been developed. Ultra-short pulsed laser radiations were effectively utilized to induce material ablation with controlled structural damages, enhancing the productivity and efficiency of the grinding process through reduced grinding forces, temperatures, and tool wear. Furthermore, this study investigated the influence of grinding tools' specifications, design variations, and parameters on key aspects such as grinding forces, surface quality, and tool wear. Substantial reductions of up to 70% in tangential grinding forces, 83% in normal grinding forces, and a modest improvement in surface roughness achieved. The surface integrity analysis revealed a damage-free ground surface when utilizing laser assistance. Furthermore, there was a substantial enhancement in the grinding ratio (G-ratio), achieving an increase of up to 247%, concurrently with a noteworthy improvement in the actual removal depth, reaching up to 99%, when compared to conventional grinding processes. Compared to the utilized segmented metal bonded diamond grinding wheel, the vitrified bonded diamond grinding wheel induced lower grinding forces and higher actual removal rates.

Research on the Grinding Performance of an Electroplated Coarse-Grained Diamond Grinding Wheel by Dressing

The coarse-grained electroplated diamond grinding wheels is increasingly favored in precision grinding of hard and brittle materials owing to its high material removal efficiency, high wear resistance and steady surface contour accuracy. However, how to determine whether the dressed grinding wheel surface topography can achieve the desired precision ground surface quality is still a huge challenge to this day. In this paper, a novel numerical simulation model, which was established basing on the statistical features of actual electroplated coarse-grained diamond grinding wheel and the kinetics of the grinding process, was proposed for theoretically and thoroughly studying the influence of the surface dressing depth of coarse-grained electroplated diamond grinding wheel on ground workpiece surface morphology. At first, the statistical features of actual electroplated coarse-grained diamond grinding wheel was acquired and a novel numerical grinding wheel surface model was established. Subsequently, a numerical ground workpiece surface simulation model was also developed. And then, the evolving mechanism of the grinding wheel surface topography with the dressed wheel surface abrasive grain protrusion height was theoretically studied by numerical simulation. Moreover, the influence of the wheel surface abrasive grain protrusion height on the ground surface roughness was thoroughly researched by means of theoretical model and experiments. The simulation and experiments results in this paper indicated that precision ground workpiece surface with nano-scale surface roughness can be acquired by grinding with a dressed grinding wheel with a certain abrasive grain protrusion height of 25% of the typical abrasive size. Comparing with the undressed grinding wheel (grinding wheel with original surface topography and not be dressed), the surface roughness Sa and Sq of the surface ground with a well-dressed wheel can achieving a significant decrease of 97.75–99.77% and 97.57–99.73%, respectively. Therefore, carefully dressing the electroplated coarse-grained diamond grinding wheel is of great significance for obtaining a precision ground workpiece surface quality.

Grinding force model for ultrasonic assisted grinding of γ-TiAl intermetallic compounds and experimental validation

Abstract The introduction of ultrasonic vibration in the grinding process of γ-TiAl intermetallic compounds can significantly reduce its processing difficulty. It is of great significance to understand the grinding mechanism of γ-TiAl intermetallic compounds and improve the processing efficiency by studying the mechanism of ordinary grinding of abrasive grains. Based on this, this study proposes a grinding force prediction model based on single-grain ultrasonic assisted grinding (UAG) chip formation mechanism. First, the prediction model of grinding force is established based on the chip formation mechanism of abrasive sliding ordinary grinding and the theory of ultrasonic assisted machining, considering the plastic deformation and shear effect in the process of material processing. Second, the UAG experiment of γ-TiAl intermetallic compounds was carried out by using diamond grinding wheel, and the unknown coefficient in the model was determined. Finally, the predicted values and experimental values of grinding force under different parameters were compared to verify the rationality of the model. It was found that the maximum deviation between the predicted value of tangential force and the actual value is 23%, and the maximum deviation between the predicted value of normal force and the actual value is 21.7%. In addition, by changing the relevant parameters, the model can predict the grinding force of different metal materials under different processing parameters, which is helpful for optimizing the UAG parameters and improving the processing efficiency.

Research on ultrasonic grinding ZrO2 ball valve with a cup-shaped diamond grinding wheel

Research on ultrasonic grinding ZrO2 ball valve with a cup-shaped diamond grinding wheel