Abrasive Particle Size Research Articles

Determination of lapping parameters for silicon wafer using an artificial neural network

An artificial neural network (ANN) simulation was utilized to determine the lapping parameters such as rotation speed, lapping duration and lapping pressure under a constant slurry supply for n-type crystalline Silicon (c-Si) wafers. Experiments were done with a Logitech PM5 lapping and polishing machine to obtain input data and target data for training, testing and validation of ANN. Lapping operation had five main parameters affecting surface quality: rotation speed, lapping duration, lapping pressure, flowrate of abrasive slurry and particle size in abrasive slurry. However, in this study slurry flowrate was assumed constant due the researches performed before. 218 lapping operations were performed with different values of the selected parameters and new lapping parameters were derived for different lapping conditions to achieve the best surface quality by using an ANN. In this study, wafers in 400 µm thickness cut under identical conditions from n-type single c-Si ingot in a STX 1202 DWS cutting machine were employed. Surface roughness (R a ) values were measured three times from different points of the wafers after lapping with a contact type surface roughness measurement tool using a microscopic scale stylus profiler (SP). In ANN simulation 70% of R a values were utilized for training, 15% of R a values were utilized for validation and 15% of R a values were utilized for test data. Results obtained from ANN simulation validated with a success above 99%.

Disintegration and recycling possibility of selected abrasives for water jet cutting

Este trabajo presentó un estudio de la desintegración abrasiva en un chorro de agua abrasivo de 400 MPa (AWJ). El tamaño y la distribución de partículas abrasivas juegan un papel importante en el mecanizado y la eficacia de corte de los chorros de agua abrasiva. Abrasivo de granate probado, comúnmente utilizado en el tratamiento con chorro de agua abrasivo y corindón. Es de interés científico observar la desintegración de estas partículas que han sido interactivas con materiales abrasivos poco comunes. El impacto del tiempo de los granos abrasivos en la pieza de trabajo es muy corto y no todo el grano en la corriente de poder hacer el trabajo de corte, debe esperar la posibilidad de recuperar el tratamiento abrasivo. Considerable importancia es el aumento en la capacidad de corte de granos triturados debido a revelar nuevos bordes de corte. Con base en un estudio de factibilidad, este documento presentará algunos resultados sobre los datos de corte obtenidos y muestra también el desgaste del tubo de enfoque utilizado, la principal parte responsable de la formación del chorro.

On the effect of relative size of magnetic particles and abrasive particles in MR fluid-based finishing process

ABSTRACTMagnetorheological fluid-based finishing (MRFF) process is widely used for fabrication of optical material such as glasses, lenses, mirrors, etc. Performance of the process is significantly affected by the properties (size, concentration, hardness, etc.) of the constituents of MR fluid. MR fluids have been prepared by varying three abrasive particles mean sizes (4 µm, 6 µm and 9 µm) with carbonyl iron particles (CIPs) having average particles size of 6 µm. Yield stress of MR fluids is measured using a rheometer. The composition of the fluid has CIPs of 25%, abrasive 10% (by volume) and rest of the base medium (liquid). The yield stress was evaluated at magnetic flux density of 0.33 Tesla. It is observed that MR fluid having the same particle size of CIPs and abrasive particles exhibits higher yield stress as compared to other combinations. The lowest yield stress is observed in case of 9 µm abrasive particles size. A set of finishing experiments is carried out to understand the effect of relative size of magnetic particles and abrasive particles on surface roughness values.

A Novel Particle Sizing Method for Nano Abrasives in CMP Slurry by Using Fluorescent Nano Probe

In this study, a novel particle sizing method is proposed based on Brownian diffusion analysis for abrasive particles using fluorescent probing. A fluorescent probe is used to measure the average dynamic viscosity of the nanoparticle dispersion in a solvent. By measuring both the average dynamic viscosity and the size of the nanoscale abrasive particles simultaneously, the uncertainty of the particle sizing is considered to be improved based on the viscosity compensation for the Brownian diffusion of nanoparticles. In this research, the authors investigate the difference between the nanoviscosity and the shear viscosity of the solvent to verify the efficacy in using viscosity compensation for nanoparticle sizing.

Effect of surface roughness on interlaminar peel and shear strength of CFRP/Mg laminates

In this study, grit blasting with different abrasive particle sizes was carried out on magnesium alloy sheets, then the carbon fiber reinforced polymer (CFRP)/magnesium alloys laminates were prepared using a hot-press process. The surface characteristics of magnesium alloy, and the interlaminar strength of CFRP/Mg laminates were examined, in order to investigate comprehensively the effect of surface roughness on interlaminar strength of laminates under peel and shear loading conditions. The results show that the rougher surface significantly improves the peel strength of laminates, while the shear strength of laminates increases only slightly with increasing surface roughness. Hence, the rougher surface exhibits a good overall interlaminar strength under peel and shear loading when compared to the smoother surfaces.

Abrasive wear resistance of selected woods

In this contribution, the results of the wear resistance study of 10 sorts of wood (apple, aspen, beech, hornbeam, horse-chestnut, London plane, mahogany, silver fir, sour cherry and sweet cherry) are published. The laboratory tests were carried out using the pin-on-disk machine when the abrasive clothes of three different grits (240, 120 and 60) were used. The wear intensity was assessed by the volume, weight and length losses of the tested samples. From the results of the carried out tests it follows that the wear resistance of different woods is different. It was proved that the wear resistance of different woods depends on the abrasive particles size, too. Also the technical-economical evaluation was part of the carried out tests. It was univocally proved that at the intensive abrasive wear using the abrasive cloth the best results were shown by hard woods, e.g. apple, beech or mahogany. Soft woods, e.g. horse-chestnut, silver fir or sweet cherry, are cheap, but their wear is bigger compared to hard woods.

Effect of hardness, microstructure, normal load and abrasive size on friction and on wear behaviour of 35NCD16 steel

Wear and friction properties depend on many parameters such as normal load and material hardness. However, coupled contributions of microstructure and abrasive particle size are less investigated. A contribution in this field is proposed with wear tests performed between a 35NCD16 steel and abrasive silicon carbide grains ranging from 35µm to 200µm under different normal loads (50–110N). To vary hardness and microstructure, samples are subjected to water quenching and tempering at various temperatures (200–600°C). These heat treatments result in a martensitic microstructure with various levels of carbon contents and carbide precipitations. For a given microstructure and hardness, the friction coefficient decreases with increasing the normal load and/or decreasing the abrasive particle size. However, the wear rate increases with increasing the normal load and/or the abrasive particle size. For high normal loads, the results also reveal that the friction coefficient decreases when the hardness and the martensite volume fraction increase. Nonetheless, for low normal loads, a transitional microstructure from martensite laths to carbides and equiaxed grains, for a tempering around 400°C, impacts the friction coefficient. Whatever the normal load, this transitional microstructure also influences the wear rate.

Effect of abrasive particle size on friction and wear behaviour of various microstructures of 25CD4 steel

Many parameters, such as normal load and material bulk hardness, control the wear and friction behaviours of materials. Nonetheless, the investigation of the coupled contributions of microstructure and abrasive particle size are still lacking. A contribution is proposed by using steel pins with various microstructures with a similar macro-hardness (around 410HV) and chemical composition. A quenched martensitic microstructure, a tempered martensitic microstructure and three ferrite-martensite dual-phase microstructures, with a similar martensite volume fraction (around 67%) and different martensite colony morphologies, are established. Friction tests are performed between these pins and abrasive papers with different sizes ranging from 15μm to 200μm. Compared to single-phase microstructures (quenched and tempered martensitic microstructures) and whatever the abrasive particle size, ferrite-martensite dual-phase microstructures reduce the friction coefficient and provide better wear resistance. For the ferrite-martensite dual-phase microstructures and unlike fine and fibrous martensite colonies, coarse and granular martensite colonies minimize the friction coefficient. In addition, characterized by a change of wear mechanisms between abrasion and adhesion, an intermediate abrasive particle around 35 μm minimizes the friction coefficient. This study also reveals that the wear rate increases with the abrasive particle size which is associated to an increase of the attack angle of abrasive grains.

Effects of carbides on abrasive wear properties and failure behaviours of high speed steels with different alloy element content

High speed steels (HSSs) are effective materials applied in aggressive environments where abrasion resistances are required because they have hard carbides and relatively ductile matrix to bind carbides. But there are many kinds of carbides in HSSs, which lead to different effect on wear properties of HSSs. In this paper, three kinds of casting HSSs with VC, M6C or M2C type carbide were prepared respectively through the reasonable design of alloy elements, and then the effects of carbide type on wear behaviours were researched under different abrasive particle size and load using abrasive wear testing machine. The microstructures and failure behaviours of HSSs were analyzed by electron microscopy. The results showed the abrasive particle size and load had obvious effect on wear weight loss of high speed steel (HSS), but the carbide type decided the relative wear resistance of HSS. As the abrasive particle size or load increased, the wear weight loss of any HSS increased obviously. For the fine abrasive wear, the HSS with M6C had higher relative wear resistance than HSS with M2C. But the contrary was the case for the coarse abrasive wear. For any abrasive particle size and load, the HSS with VC had more excellent wear resistance than HSS with M6C or M2C type carbide. The relative wear resistance of HSS with VC was three times higher than that of HSS with M6C or M2C. The excellent wear resistance of HSS with VC was mainly attributed to VC characteristics, such as high hardness and good morphology, which can resist micro-cutting of abrasive particles efficiently.

Effect of abrasive particle size on slurry abrasion resistance of austenitic and martensitic steels

The effects of the abrasive particle size and the pH-value of the aqueous solution on the abrasive wear resistance of H–13 steel and Hadfield steel were investigated. Abrasive wear tests, using a wet rubber wheel abrasion tester, were carried out applying abrasive sizes in the range of 0.15–2.40mm. The pH-values of the aqueous solution ranged from 5.5 to 12.8. The microstructure of each material was characterized with optical microscopy. The wear surfaces and the wear particles (debris) were analyzed by scanning electron microscopy (SEM). The macro- and microhardness were measured before and after the wear tests using a Vickers hardness tester. The surface topography of the wear scars was examined by a non-contact 3D profiler in order to measure the depth of the abrasive penetrations.The results demonstrated that Hadfield steel is more wear resistant than H-13 steel for all pH-values and all abrasive particle sizes used in the tests. Moreover, the micro-hardness of the wear scar surface of the Hadfield steel increased significantly with the size of the abrasive grain, while this increase was lower for the H-13 steel. The greater work-hardening of the austenitic Hadfield steels was considered to be responsible for this higher wear resistance in comparison with the martensitic H-13 steel. For both materials the loss of mass increased linearly up to a critical abrasive particle size (CPS); this CPS, the mass loss continued to increase but with a lower gradient. An explicit effect of the steel matrix on the mass loss behavior as a function of the abrasive grain size was not observed. The less acidic aqueous solution resulted in lower mass losses for both materials and for all abrasive grain sizes. This effect was greater for the two smaller abrasive grain sizes. For higher pH-values, lower depths of penetration of the abrasive particles were observed. The analysis of the wear particles in all test conditions displayed continuous and discontinuous chips for the H-13 steel but only discontinuous chips for the Hadfield steel,. For both materials two abrasive wear micromechanisms were determined: microcutting and microploughing. Finally, the results presented in this work suggest that the wear performance analysis of Hadfield steel, to be used in an abrasive environment, should consider the effects of the pH value of the aqueous solution and the abrasive particle size.

Abrasive Wear Behaviour of Surface Modified Jute Fiber Reinforced Epoxy Composites

The present article depicts the specific wear rate of jute fiber reinforced epoxy composites with different weight percentage of fiber loading (10, 20, 30, 40 wt. %) and different chemical treatments (Alkaline and Benzoyl chloride treatment). The three-body abrasive wear analysis was studied according to ASTM-G65 using a rubber wheel abrasion apparatus (dry sand wear tester) at room temperature by varying different factors like fiber content, abrasive particle size, normal load and sliding distance. To calculate the abrasive wear behaviour of jute/epoxy composites, the design of experiments approach based on Taguchi’s orthogonal array has been adopted. Steady state result shows that with the inclusion of chemical treatment in jute fiber improved wear resistance capacity of the composites. Finally, scanning electron microscope (SEM) studies revealed the morphologies worn surface of the composites such as micro-ploughing, formation of debris, micro cracking and fiber matrix de-bonding.

The Effect of Silica Abrasive Particle Sizes in Polyester Based Composite on the Tribological Properties of Ti64

Investigation of the tribological characteristics of Ti6Al4V (Ti64) was performed by using a pin-on-disc tribometer. Polymer composites composed of a polyester resin matrix and silica abrasives with two different particle sizes were used as the counterface pin material. The macro and micro surface features on the wear track in relation to different abrasive particle sizes were analyzed by using optical microscope and scanning electron microscope. The wear depth was monitored by utilizing surface profiler and the change in hardness of Ti64 was measured by using Vickers hardness tester before and after the test. The effect of sliding speeds on the coefficient of friction was also studied. During sliding against Ti64 substrate, the results showed lower coefficient of friction, smoother surface features, and lower wear rate for the case of the polymer composite pin with smaller silica particles size when compared to that of polymer composite pin with larger silica particles size. The higher sliding speed generated more wear debris, much deeper wear depth, and wider wear track on Ti64 substrate.

Numerical simulation study on erosion mechanism of pre-mixed abrasive water jet

In order to optimize the parameters of the pre-mixed abrasive water jet cutting technology and make it more efficient in the coal mine gas environment, finite element analysis software LS-DYNA is used to simulate single abrasive particle of rock erosion rule and analyze the influence of different particle size, different grinding particle impact velocity, different abrasive particle shape on rock erosion effect. The results show that under the same conditions, the greater the impact velocity, the better the erosion effect, and the erosion rate of abrasive particles is almost linear with the erosion rate of rock. With an increase in velocity of abrasive particles, the erosion rate of cube shape of abrasive particles is gradually higher than that of spherical particles of abrasive. The larger the particle size of abrasive particles, the bigger the kinetic energy of them and also the erosion depth and erosion volume on the rock and steel. But when the particle size increases, the erosion rate of abrasive particles on the rock will decrease gradually. The research results provide theoretical basis for optimizing the parameters of pre-mixed abrasive water jet cutting.

Material removal mechanism of copper chemical mechanical polishing with different particle sizes based on quasi-continuum method

In this paper, the material removal mechanism of copper chemical mechanical polishing was studied by the quasicontinuum method that integrated molecular dynamics and the finite element method. By analyzing the abrasive process of different particle sizes on single crystal copper, we investigated the internal material deformation, the formation of chips, the stress distribution, and the change of cutting force. Results showed that shear band deformation was generated along the cutting direction at approximately 45° inside the workpiece material. The deformation was accompanied by dislocations and sliding phenomena in the shear band region. Smaller abrasive particle size led to poor quality of the workpiece, while a larger particle size led to better quality. However, larger particle size resulted in greater plastic deformation and deeper residual stress inside the workpiece. Size change of abrasive particles had little effect on the tangential cutting force.

Optimization of process parameters affecting surface roughness in magnetic abrasive finishing process

ABSTRACTDevelopment in manufacturing technology enhances the mechanical behavior of machined parts and improves the surface finish with high precision, which conveys the progressive importance of magnetic abrasive finishing (MAF) process. In current research work, magnetic abrasive particles were used as finishing tools during the MAF process. However, these magnetic abrasives are fabricated by special techniques, i.e., the adhesive bonding-based method, the sintering method, the plasma-based method and so on. The present study explores the basic finishing characteristics of the magnetic abrasive produced by the sintering process. After the sintering process, improved quality of magnetic abrasives was obtained, where the abrasive particle sticks on the base metal matrix. The abrasive particle used is alumina powder and the magnetic particle is iron powder. Experiments were performed on Stainless Steel 202 to inspect the sound effects of several process parameters such as rotational speed, electromagnet voltage, machining gap and abrasive particle size on machining performance. Apart from that, surface roughness was also measured, which revealed the influence of the abrasive particle on the machined surface in terms of surface finish. It is observed from this study that appropriate size of magnetic abrasive particle optimizes the surface finish.

Influence of Load and Size of Abrasive Particle on Micro-pore Texture on Metal Surface

Influence of Load and Size of Abrasive Particle on Micro-pore Texture on Metal Surface

Optimisation of testing parameters on two-body abrasive wear behaviour of nano-oMMT filled carbon-epoxy composites based on the Taguchi method

Two-body abrasive wear behaviour of carbon fabric reinforced epoxy (C-E) composites and nanosized organo modified montmorillonite (oMMT) particles dispersed C-E hybrid composites was investigated. Abrasive wear tests were carried out using a pin-on-disc machine under multi-pass condition. Silicon carbide (SiC) waterproof abrasive papers of different particle sizes were used under dry abrasion conditions. The influence of tribological parameters like applied normal load, abrading distance, filler loading and particle size of the SiC abrasives on the wear volume was investigated. Routine experimental results indicate that the wear volume depends on wt % of oMMT loading and the specific wear rate decreases with increase of abrading distance and increases with increasing load for all the composites. The scanning electron microscopy pictures indicate the reasons for failure of composites and influencing parameters. The orthogonal array, signal-to-noise ratio and analysis of variance were employed to study the optimal testing parameters on oMMT filled carbon-epoxy composites with 20 µm and 40 µm SiC particle sizes. The experimental results demonstrate that the abrading distance was the major parameter on abrasive wear, followed by filler loading and applied normal load. The particle size of SiC, however, was found to have a neglecting effect. Moreover, the optimal combination of the testing parameters could be predicted. Regression analysis was used to arrive at a mathematical model to predict the wear volume in terms of tribological parameters. The predicted wear volume of the composites was found to lie close to the experimental values.

Analytical on mixed colloidal silica particle in slurry of sapphire Chemical Mechanical Polishing

Mixed colloidal silica particles as abrasive in slurries have been proposed to improve and realize a high removal rate and smooth surface without subsurface damage, on sapphire chemical mechanical polishing (CMP). Mixed silica particles were fabricated by different sizes of nano-silica particle with the range of pH 7-13. The characteristics of the mixed large and small silica particles has been observed. Dynamic light scattering (DLS) spectra results revealed that the structure of the mixed particle, the small particle at the size of 4 nm are adsorbed on the large silica particles and increase in the size of the abrasive particles. Furthermore, we found that pH value affected to abrasive particle size. In these cases, our polishing tests results show that material removal rate (MRR) of the sapphire CMP totally increase. This confirmed that mixed particles could produce a higher MRR than single colloidal silica slurry. Finally, the mechanism of sapphire removal was discussed.

Effect of abrasive particle size on tribochemical wear of monocrystalline silicon

Using atomic force microscopy, the nanowear of hydrogen-terminated silicon surface was investigated in water with spherical SiO2 tips. The radii of tips can significantly affect the material removal of silicon surface and large tip could result in substantial wear and high friction force. Analysis suggests that the increase in contact area could enhance the tribochemical reaction by forming more Si-O-Si bonding bridges at Si/SiO2 interface. Thus, for the tribochemical wear of silicon under elastic contact condition, the abrasive particle size dependence of material removal was more attributable to the change of contact area than to the change of indentation volume. These results may help gain a profound insight into the influence of abrasive particle size on tribochemical wear of silicon.

Effects of Grit Blasting on Surface Properties of Adhesive Bonded Adherents

A mechanical treatment of an adherent before an application of adhesives is one of key factors influencing resultant strength of an adhesive bond. A grit blasting belongs among one of the most often used methods of the surface treatment. A resultant structure of blasted adherent and also parameters of the surface roughness can be changed during the blasting by a suitable choice of many parameters among which a material and a size of abrasive particles, a distance of an air jet and a blasted material, a size of the jet, an air pressure and an angle of abrasive particles impact can be ranked. This experiment describes an injector system of grit blasting using basic abrasives - corundum and glass ballotini. During grit blasting of common steel adherent it came to the change of the impact angle of the abrasive particle in a range from 75° (a perpendicular angle) to 10°. Different impact angle led to different roughness parameters and to various structure of the adherent surface which was evaluated by an electron microscopy. Subsequently, it came to experimental description of the strength of adhesive bonds which were created by adherents whose surface was grit blasted under various impact angles of abrasive particles.