Abrasive Particle Size Research Articles

Effects of Frequency on the Performance of Ultrasonic Vibration Assisted Chemical Mechanical Polishing for Sapphire

Abstract Sapphire (Al2O3) is renowned for its exceptional properties, yet its unique natural presents a surface processing challenge. To enhance the polishing quality and efficiency, the sapphire ultrasonic vibration assisted chemical mechanical polishing (UV-CMP) has been proposed. This paper employs computational fluid dynamics (CFD) simulation and polishing experiments to investigate the action and mechanism of ultrasonic frequency on sapphire UV-CMP. The CFD simulation reveals that an increase in frequency can effectively elevate the fluid velocity, pressure, and cavitation. The enhancement in pressure, Z-direction, and resultant velocity has a positive impact on the cutting ability and utilization rate of nano-abrasives. A high frequency can enhance the physical fields of slurry, but it suppresses the growth of cavitation bubbles, and is detrimental to the number and size of abrasive particles. The best processing performance of sapphire UV-CMP is obtained at 40 kHz due to coordinated physicochemical interactions. X-ray photoelectron spectroscpy proves the product of solid-solid chemical reaction between nano-SiO2 and sapphire is softer Al2Si2O7 instead of Al2SiO5, which is beneficial to the material removal. This article provides theoretical and practical guidance for sapphire UV-CMP.

Research on high‐pressure abrasive water jet slotting and pressure relief technology for hard rock roof

AbstractTo solve the problem of severe rock pressure near coal mining face tunnels, a high‐pressure abrasive water jet slotting and roof breaking pressure relief technology is proposed. First, the laneway deformation mechanism and the process of hard rock slotting using high‐pressure abrasive water jets under long‐distance cantilever conditions are analyzed, and the crack initiation conditions of roof strata are obtained. Second, slotting tests under different slotting pressures, nozzle diameters, abrasive particle sizes and slotting times were carried out, and the slotting parameters of a high‐pressure abrasive water jet on a typical roof rock were obtained. Finally, industrial application was carried out in the 81,403 working face of Huayang No.1 Mine. After the hydraulic roof slotting measures were implemented in the test area, the maximum axial force of the anchor cable was reduced to 67 kN, which was 35.5% lower than that of the comparison. The average stress of the coal seam was 15 MPa, which was approximately 25% lower than that of the comparison. The deformation of the tunnel in the experimental area was significantly controlled, with an average movement of 30.0% toward the roof and floor of the tunnel and an average movement of 23.2% toward the two sides of the tunnel. Compared with the movement in the comparison section, the movement toward the roof and floor of the laneway was 42.3% lower, and the movement toward the two sides was 38.2% lower. The industrial application results show that high‐pressure abrasive water jet roof slotting and pressure relief technology can cut off the stress transmission path between the roof rock on both sides, effectively improve the stress state of the surrounding rock of the laneway, reduce the deformation of the roof, floor and two sides of the working face in the later stage of the mining laneway.

Review on chemical mechanical polishing for atomic surfaces using advanced rare earth abrasives

Abstract During the past decades, high-performance devices and setups have been widely used in the fields of precision optics, semiconductors, microelectronics, biomedicine, optoelectronics and aerospace. It is a challenge to achieve ultralow surface roughness free of damages. Due to the unique physicochemical properties of rare earths, ceria has garnered great progresses for atomic surfaces induced by chemical mechanical polishing. Compared with conventional mechanical removal by alumina and silica, rare earth abrasives achieve selective material removal on surface via their special chemical activity, without introducing microscopic scratches and defects. Nevertheless, polishing performance of rare earth abrasives depends on series of factors, e.g. size of abrasive particles, microscale topological structure, configuration of chemical slurry, auxiliary energy fields etc. As a result, it is significant to conduct a comprehensive review to understand state-of-the-art polishing technologies. This review summarizes the effect of polishing slurries composed of different rare earth abrasives on polishing performance under different conditions. Additionally, various energy-assisted polishing strategies are discussed using diverse kinds of rare earth abrasives for distinct polishing forms. Finally, future directions of polishing on rare earth abrasives are addressed.

Dimensional and experimental analysis for predicting the material removal rate in AJM

ABSTRACT One of the upcoming methods for machining brittle and heat-sensitive materials is abrasive jet machining (AJM) where the process of erosion aids in material removal. This is accomplished by the impact of abrasives transported using a stream of gas having high velocity onto the workpiece. The erosion mechanism is a complicated process, which involves cutting, fracturing and micro structural transformation, thereby causing the evaluation of response parameter like rate of material removed (MRR) an arduous task. In this paper, an effort has been made to develop a semi-empirical model for predicting MRR in hole machining of soda-lime glass by utilising dimensional analysis (DA) technique. In this model, the compressive stress developed during the impact of loading and velocity of the particle are considered as a function of work material, selected abrasive material properties and process parameters. The validation of the evolved model was carried out with experiments that involve process parameters such as operating pressure, stand of distance (SOD) and abrasive particle size. From the analysis, it’s found that the predicted MRR model created by the dimensional analysis method gave an average error of 11.8%. thereby giving a reasonably compatible value with experimental results.

Research on the generation mechanism of surface and subsurface damage in loose abrasive lapping of RB-SiC ceramics

Reaction-bonded silicon carbide ceramics (RB-SiC) are extensively utilized in aerospace, space optics, and other fields due to their superior physical and chemical properties. Loose abrasive lapping plays a crucial role in the optical manufacturing of large-diameter RB-SiC mirrors. Previous research predominantly focused on grinding processes and overlooked the removal mechanism during lapping and their impact on surface and subsurface damage. In this study, a three-body brittle fracture removal model was established to explore the removal mechanisms of RB-SiC. Additionally, experiments were carried out to investigate the influence of abrasive particle size on the surface and subsurface damage. Experimental results confirm the theoretical model and indicate that for RB-SiC, different particle sizes correspond to distinct removal mechanisms, causing abrupt changes in surface roughness, while the layer under SiC acts as a buffer against the propagation of subsurface damage. These findings help optimize the manufacturing process, improve lapping efficiency, and enhance mirror performance.

Experimental investigation on the surface topographical improvement of selective laser melted SS316L using abrasive flow finishing

Selective laser melting (SLM) offers a precise fabrication of intricate geometries that are not achievable with conventional manufacturing processes. However, surface imperfections like adhered powder particles, waviness, and other anomalies impede the intended functional application and demand additional post-processing steps. Abrasive flow finishing (AFF) process is extensively used for enhancing the surface topography of SLM-built parts by reciprocating a viscoelastic polymer abrasive medium. The cost of commercial abrasive media is expensive, needs costlier and heavy equipment, has little tolerability, and releases hazardous gases during its preparation. In this work, a biopolymer-based abrasive media is developed in-house and employed to examine the surface topographical changes of SLM-built SS316L flat features. Compared to commercial abrasive media, the cost of the developed abrasive media is much lower, does not require expensive equipment, and is eco-friendly. The effect of extrusion pressure, number of finishing cycles, and size of the abrasive particles on the percentage change in areal surface roughness (%ΔSa) and waviness (%ΔWa) was studied. From the analysis of variance, irrespective of %ΔSa and %ΔWa, it was found that the number of cycles was the most contributing process parameter, followed by extrusion pressure and abrasive particle size. The optimised process parameters resulted in a maximum %ΔSa and %ΔWa of about 90.1 % and 66.25 %, respectively, from the initial as-built areal surface roughness of 6.6 ± 0.2 μm and areal surface waviness of 7.7 ± 0.4 μm.

Theoretical Study of the Size and Amount of Abrasive Particles in Motor Oil Involved in the Wear Process of Cam Profile

The article presents the results of a theoretical study of the amount and size of abrasive particles in the motor oil that cause wear of the gas distribution mechanism and the profile part of cam. The reliability of the results was evaluated on the basis of the experimentally determined values ​​of wear indicators of the input and output cams of the camshaft.

Experimental analysis and machine learning with IoT monitor in two-way abrasive flow machine polishing on P20 mold components

The purpose of this paper was to reveal the effects of pressure and time on the surface roughness (Ra) and compare the experimental design (Factorial Regression) and machine learning (ML) of steel mold workpieces. Methodology began with turning, and fine sandpaper P180 to P1200 and measured with an initial value of Ra compared with the final value of Ra at the end of the two-way prototype AFM process. The process parameters are as follows; abrasive particle size (alumina; Al2O3) 5.0 μm in Silicone Oil (concentration 50% by weight) at pressures (p) of 10 bar and 20 bar, processing time (t) 5, 15, and 25 min, specimens P20 Mold steel. The experimental results show that under these conditions. The average surface roughness of the specimens differed from the initial value by Ra 0.034 to 0.021 μm, with delta values ranging from 0.011 μm to 0.005 μm. The results showed a smoother profile between before and after polishing. The approach to the topic is DOE and ML, and the theoretical or subject scope of the paper is Statistical and AI. The original value of the paper is applied to the ESP32 Arduino to control and display critical parameters. A General Factorial Regression statistical value of 76.39% is acceptable. A pressure factor of 20 bars and a time of 25 minutes gives the best effect on surface roughness. ML assisted in predicting the Surface Roughness for optimization based on the experiment.

Investigating the solid particle erosion behavior of H3BO3 / B2O3 / SiO2 / Al2O3 reinforced glass fibre/epoxy composites and parametric evaluation using artificial intelligence

In this experimental study, the erosion wear behavior of glass fibre-reinforced (GF) composite materials was examined according to ASTM G76–95. Pure/GF reinforced epoxy composite (EP) materials were chosen as the main test sample. Boric Acid (H3BO3), Borax (B2O3), Silicon Dioxide (SiO2), and Aluminium Oxide (Al2O3) were added to the resin as reinforcement at a rate of 15% by weight. The erosion wear rate was investigated with various impingement angles (30°, 60°, and 90°), impact velocities (≈23, 34, and 53 m/s), alumina abrasive particle sizes (≈200 and 400 μm), and fibre directions (0° and 45°). Neural network models were employed effectively to predict the influence of the reinforcements on erosive wear rate. The erosive wear rate indicated that Al2O3 added GF/EP exhibited the most anti-erosive characteristics followed by silicon dioxide GF/EP and pure GF/EP however, the anti-erosive nature of GF/EP deteriorated with the addition of Borax and Boric Acid.

Methodologies for calculating abrasive particle size in gear wear

Abstract In agriculture, when cultivating crops, many agro-technical operations are carried out and many different agricultural machinery and equipment are used in these processes. To drive various mechanisms and working bodies of these technical means and equipment, various drive or transmission mechanisms are used from one part of the equipment to another. Among them, the most common type of transmission mechanisms are gear mechanisms. According to operating conditions, gear mechanisms are divided into those operating in an open, dry state and those operating in a closed, wet state, mostly in oil. However, during the operation of gear mechanisms, wear of the teeth is observed. Practice shows that for wear of gear teeth, despite their operating conditions, working them in an open dry state or working them in a closed wet state, mainly on oil, abrasive particles show a great influence. Based on this, the article presents the results of the development of a methodology for calculating the size of sample particles leading to wear of gear teeth.

In-Vitro Analysis of Polyethylene Liner Wear Performance at 3 and 5 Million Cycles

The purpose of this study is to compare the wear properties of UHMWPE acetabular liners after undergoing 3 million (3 Mc) and 5 million (5 Mc) cycles of in-vitro wear testing. The results will serve as a reference for the design of in-vitro testing for hip prostheses and as a control for clinical revision removals. Wear tests were conducted on three different sizes of acetabular liners (28 mm, 32 mm, and 36 mm internal diameters) using a hip simulator to determine the amount of wear after 3 and 5 million cycles. The analysis included the number, size, and shape of abrasive particles. After 3 and 5 million cycles of wear, the amount of wear on the acetabular liner increased as the inner diameter increased. The abrasive particles had an average equivalent circular area diameter (ECD) of 0.27 μm and 0.29 μm, and 94.4% and 90.1% of the aspect ratio (AR) less than 4. The amount of wear on the acetabular liner after 3 Mc wear can indicate the wear performance of the product. The number of particles increased and the percentage of fibrous particles was higher after 5 Mc wear compared to 3 Mc wear.

STUDY ON THE FRICTION AND WEAR PROPERTIES AND SURFACE INTEGRITY OF GCr15 BEARING STEEL UNDER DIFFERENT GRINDING METHODS

In the field of precision machining, there are two widely used grinding methods for the same type of abrasive, namely, fixed abrasive grinding, and free abrasive grinding. In this paper, we utilized a self-developed rolling-sliding ratio controllable friction and wear testing machine to investigate the friction and wear properties of GCr15 bearing steel ground by fixed/free abrasive grinding under rolling and sliding motion, with varying abrasive particle sizes. The surface morphology and roughness of the ground bearing steel were observed and measured using a laser confocal microscope and white light interferometer. Results showed that under rolling and sliding conditions, the coefficient of friction for fixed abrasive grinding was higher than for free abrasive grinding. Under sliding conditions, the grinding efficiency of the fixed abrasive wheel is higher. However, in the case of wheel blockage, the grinding efficiency would significantly decrease. Conversely, the grinding efficiency of free abrasive grinding was observed to be stable throughout the grinding process. Under the same conditions of abrasive particle size in the sliding state, free abrasive grinding showed better surface integrity of bearing steel compared to fixed abrasive grinding.

Processing Optimization for Halbach Array Magnetic Field-Assisted Magnetic Abrasive Particles Polishing of Titanium Alloy.

To extend the working life of products made of titanium alloy, it is necessary to improve the polishing method to diminish the remaining defects on the workpiece surface. The Halbach array-assisted magnetic abrasive particle polishing method for titanium alloy was employed in this work. The distribution of magnetic field strength was simulated and verified at first to learn the characteristics of the Halbach array used in this work. Then, the polishing performance of the polishing tool was studied by conducting the polishing test, which aimed to display the relationship between shear force and surface roughness with polishing time, and the surface morphology during polishing was also analyzed. Following the establishment of the response surface model, a study on the optimal polishing parameters was conducted to obtain the suitable parameters for maximum shear force and minimum surface roughness. The results show that the maximum shear force 6.11 N and minimum surface roughness Sa 88 nm can be attained, respectively, under the conditions of (1) polishing tool speed of 724.254 r·min-1, working gap of 0.5 mm, and abrasive particle size of 200 μm; and (2) polishing tool speed of 897.87 r·min-1, working gap of 0.52 mm, and abrasive particle size of 160 μm.

On surface texture evolution in abrasive flow machining

ABSTRACT Abrasive Flow Machining (AFM) is highly effective for precise surface control and finishing. The process’s material removal mechanism significantly impacts surface quality, especially in complex parts. However, little research addresses how initial micro-surface textures affect AFM outcomes. This study prepared four types of initial surface profiles and machined them using various abrasive media particle sizes. The rheology of the abrasive media was analyzed, with a custom guide restricting the fluid domain to create gradient flow changes. Both experimental and simulated one-way and two-way AFM processes were conducted. Results demonstrated that the material removal efficiency improved according to an enhanced version of Preston’s equation for flat surfaces. Initial surface textures exerted more influence on material removal than anticipated. All abrasive media sizes yielded uniform surface quality, with surface roughness improvements exceeding 80%. Larger initial surface textures experienced greater material removal. Chemical element analysis confirmed the AFM process is contamination-free.

EXPERIMENTAL INVESTIGATION ON ONE-WAY ABRASIVE FLOW MACHINING ON HOT WORK STEEL

Abrasive flow machining (AFM) is a process where a semi-solid abrasive-laden media is forced to flow through the internal passages of a workpiece under pressure. In high-resolution work, increased accuracy and faster smooth surface polishing work with the developed motorized AFM prototype. This research presents the effect of the clearance of specimen tools for surface roughness (Ra) of SKD 61 (AISI H13) hot work steel related to AFM. This research experimented with half-spherical specimens. AFM experiments are performed to identify the improved surface roughness when applied to the polishing specimens. Specimens were prepared by being turned, hardened, and polished with sandpaper from number P180 to P1200 and measured with an original value of Ra compared with the final value of Ra at the end of the process. The experimental prototype uses a unidirectional motor drive system different from previously developed machines. The process parameters are as follows: a pressure (p) of 1, 2, and 3 bar, cycle time (t) of 10, 15, and 20 min., an abrasive particle size (Al2O3) of 5.0 μm in Silicon Oil (50 % concentration by weight), hardness of specimens 45±2 HRC, etc. The experimental results show that under these conditions, the average surface roughness of specimens was decreased from an original value of Ra 0.057 to 0.042 μm. The greatest response surface (RSM) was obtained at a pressure of 3 bar and a time of 20 minutes. The result allows for better precision control and further development in industrial applications.

Effect of Polyoxyethylene-Based Nonionic Surfactants on Chemical–Mechanical Polishing Performance of Monocrystalline Silicon Wafers

The use of surfactants is crucial in the chemical–mechanical polishing fluid system for silicon wafers. This paper examines the impact of the functional group structure of polyoxyethylene-based nonionic surfactants and the variation in the polyoxyethylene (EO) addition number on the polishing performance of monocrystalline silicon wafers, to achieve the appropriate material removal rate and surface quality. The results demonstrated that the straight-chain structure of fatty alcohol polyoxyethylene ether (AEO-9) exhibited superior performance in wafer polishing compared to octylphenol polyoxyethylene ether (OP-9) and isoprenol polyoxyethylene ether (TPEG) and polyethylene glycol (PEG). By varying the number of EO additions of AEO-type surfactants, this study demonstrated that the polishing performance of monocrystalline silicon wafers was affected by the number of EO additions. The best polishing effect was achieved when the number of EO additions was nine. The mechanism of the role of polyoxyethylene-type nonionic surfactants in silicon wafer polishing was derived through polishing experiments, the contact angle, abrasive particle size analysis, zeta potential measurement, XPS, and other means of characterization.

Parameters Optimization of Active Flexible Tool‐Assisted Shear Thickening Polishing Method for Concave Surface

An innovative approach, active flexible tool‐assisted shear thickening polishing (AFT‐STP), is introduced to overcome the limitations of low efficiency involved in the STP process of the concave surface. The principle and characteristics of AFT‐STP are presented, accompanied by the design of a flexible tool structure and the creation of an experimental setup. Utilizing the Taguchi method, experiments are planned and results are assessed via the signal‐to‐noise ratio to optimize process parameters. A variance analysis is then used to ascertain the relative influence of four key parameters—polishing speed, polishing gap, abrasive particle size, and abrasive concentration on the polishing performance of quartz glass in STP. Under the optimal parameters, a concave quartz glass workpiece with diameter Ø 20 mm and curvature radius 488 mm is polished, the average surface roughness Sa of the five measuring points on the surface decreases from 142.18 ± 8.63 (Avg. ± Std.) nm to 5.34 ± 1.16 nm in 45 min with MRR 57.3 nm min−1, and the surface defects of the processing area are completely removed, leaving only minor pits. The results show that the AFT‐STP is an effective method for high‐quality polishing of concave surfaces.

The influence of the types of cluster composite abrasives on the performance of fixed abrasive pads in processing quartz glass

To enhance the material removal rate (MRR) and surface quality of quartz glass lapping, a new method is proposed utilizing a fixed cluster composite abrasive pad (FCCAP) for processing quartz glass. Firstly, cluster composite abrasives (CCA) with a particle size of 28 μm were prepared using the normal temperature and pressure sintering method, including cluster Al2O3-diamond composite abrasives (CADCA), cluster diamond-diamond composite abrasives (CDDCA), and cluster SiO2-diamond composite abrasives (CSDCA). Secondly, using CCA as the abrasive and relying on ultraviolet curing technology, three types of FCCAP were prepared: fixed cluster Al2O3-diamond composite abrasive pads (FCADCAP), fixed cluster diamond-diamond composite abrasive pads (FCDDCAP), and fixed cluster SiO2-diamond composite abrasive pads (FCSDCAP). Simultaneously, to validate the performance of the prepared FCCAPs, three types of fixed single crystal abrasive pads were prepared using the same process with single crystal Al2O3 (SCA), single crystal diamond (SCD), and single crystal SiO2 (SCS) with a particle size of 28 μm. Using quartz glass as the processing object, lapping experiments and friction and wear experiments were conducted, with MRR, surface roughness Ra, and coefficient of friction (COF) selected as evaluation indexes to compare and study the lapping performance of the six pads. FCCAP demonstrated higher machining efficiency, with FCDDCAP achieving the highest MRR of 3.611 μm/min. Additionally, after FCCAP lapping, the surface roughness Ra of quartz glass is lower, to some extent repairing surface damage such as large scratches. Among them, FCSDCAP achieved the lowest surface roughness of 91.564 nm. Finally, FCCAP exhibits superior friction and wear performance, with FCSDCAP samples having the highest average COF of 0.127. Under the same abrasive particle size conditions, FCCAP has better processing capabilities, enabling efficient lapping of quartz glass.

Fabrication of Manually Operated Electro Magnetic Abrasive Finishing

The aim of our project is to obtain precision finishing of rough surfaces which are required to the work by addition of joystick to adjust the magnetic field on to the required surface. The magnetic field can relocated at any point by the use of joystick by the use of arduino uno board. Arduino can be used to develop interactive objects, taking inputs from a variety of switches or sensors, and controlling a variety of lights, motors, and other physical outputs. The results demonstrate the viability of the manually operated (EMAF) setup in achieving desired surface finishes across a range of materials, including metals and composites. It is designed to offer flexibility and ease of use, allowing operators to adjust parameters such as magnetic field intensity, abrasive particle size, and feed rate. Through a series of experiments and analysis, the efficiency of the fabricated system is evaluated in terms of surface roughness, material removal rate, and surface integrity. Key Words: Precision finishing, Magnetic force, Surface quality, Polishing, Manual operation.

CFD-Based Study on the Flow and Kinetic Energy Characteristics of a Supercritical Suspended Abrasive Water Jet in the Deep-Sea Environment

A supercritical suspended abrasive water jet with dual inputs of pressure and heat is proposed to improve the cutting performance of the conventional suspended abrasive water jet in deep-sea environments. The paper studies the flow and kinetic characteristics of the supercritical suspended abrasive water jet. The CFD simulation method is proposed to investigate these characteristics by integrating a programmed database of supercritical water material properties with Ansys Fluent. The simulation and comparison show that abrasive particle density, abrasive particle size, inlet pressure, and water temperature affect the acceleration process of the abrasive particles. At the nozzle outlet, the velocity of the abrasive particles reaches over 95% of the supercritical water velocity. With the proposed supercritical abrasive water jet, the jet velocity is increased by 192.2% to 402.40 m/s compared to the conventional suspended abrasive water jet, reducing the amount of water used by 67.7% at a specified temperature of 773.15 K. Correspondingly, the medium kinetic energy is increased by 177.7% and the medium kinetic energy ratio is 2.78. The particle kinetic energy is increased by 723.2% and the particle kinetic energy ratio is 8.23.