Preparation and Processing Performance of Viscoelastic Abrasive Flow

2013 ◽  
Vol 546 ◽  
pp. 55-59
Author(s):  
Lu Yang ◽  
Ke Hua Zhang ◽  
Guang Zhen Zheng ◽  
Hang Guo
Keyword(s):  
Surface Roughness ◽  
Silicon Carbide ◽  
Particle Size ◽  
Silicone Oil ◽  
Removal Rate ◽  
Abrasive Particle ◽  
Viscosity Coefficient ◽  
Advanced Technology ◽  
Dielectric Characteristics ◽  
Workpiece Surface

Abstract. Abrasive flow machining (AFM) is an advanced technology which can improve the uniform consistency of profiled surface. First, the dielectric characteristics of the abrasive flow (the medium features include medium types, medium viscosity coefficient, the concentration of medium and abrasive, abrasive type, abrasive size) is studied, abrasive flow including different medium is deployed by mixing and mix well of the polymer silicone fluid, silicone oil, wax, and other fats, and adding silicon carbide with different particle size and mixed for processing experiment. Within the limits of the workpiece polishing, the change direction of the surface roughness and the removal rate of workpiece surface are substantially same and approaching the linear relationship, the lowest surface roughness Ra of SiC (abrasive particle size is 200#) reduced from 3.5μm to 0.5μm. The hardness and durability of the silicon carbide abrasive in this study is quite good, and the price is low, the processing characteristics are quite consistent with the economic costs on the demand.

scholarly journals Study on the Electrorheological Ultra-Precision Polishing Process with an Annular Integrated Electrode

Micromachines ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 1235
Author(s):  
Cheng Fan ◽  
Yigang Chen ◽  
Yucheng Xue ◽  
Lei Zhang
Keyword(s):  
Surface Roughness ◽  
Particle Size ◽  
Applied Voltage ◽  
Abrasive Particle ◽  
Polishing Process ◽  
Workpiece Surface ◽  
Orthogonal Experiments ◽  
Single Process ◽  
Ultra Precision ◽  
Polishing Tool

Electrorheological (ER) polishing, as a new ultra-precision super-effect polishing method, provides little damage to the workpiece surface and is suitable for polishing all kinds of small and complex curved surface workpieces. In this paper, an ER polishing tool with an annular integrated electrode is developed. The orthogonal experiments are carried out on the six influencing factors of ER polishing which include the applied voltage, the abrasive particle size, the abrasive concentration, the polishing gap, the polishing time and the tool spindle speed. The influence order of these six factors on the ER polishing is obtained. On this basis, the effect of a single process parameter of ER polishing on surface roughness is studied experimentally.

INVESTIGATION OF SINGLE-POINT DRESSING OVERLAP RATIO AND DIAMOND-ROLL DRESSING INTERFERENCE ANGLE ON SURFACE ROUGHNESS IN GRINDING

2010 ◽  
Vol 34 (2) ◽  
pp. 295-308 ◽  
Author(s):  
Akram Saad ◽  
Robert Bauer ◽  
Andrew Warkentin
Keyword(s):  
Surface Roughness ◽  
Material Removal Rate ◽  
Empirical Model ◽  
Material Removal ◽  
Removal Rate ◽  
Single Point ◽  
Experimental Conditions ◽  
Workpiece Surface ◽  
Different Depths ◽  
Overlap Ratio

This paper investigates the effect of both single-point and diamond-roll dressing techniques on the workpiece surface roughness in grinding. Two empirical surface roughness models are studied – one that incorporates single-point dressing parameters, and another that incorporates diamond-roll dressing parameters. For the experimental conditions used in this research, the corresponding empirical model coefficients are found to have a linear relationship with the inverse of the overlap ratio for single-point dressing and the interference angle for diamond-roll dressing. The resulting workpiece surface roughness models are then experimentally validated for different depths of cut, workpiece speeds and dressing conditions. In addition, the models are used to derive a relationship between overlap ratio for single-point dressing, and interference angle for diamond-roll dressing such that both dressing techniques produce a similar surface finish for a given material removal rate.

Fundamental Studies on the Mechanisms of Oxide CMP

2000 ◽  
Vol 613 ◽  
Author(s):  
Uday Mahajan ◽  
Seung-Mahn Lee ◽  
Rajiv K. Singh
Keyword(s):  
Surface Roughness ◽  
Particle Size ◽  
Wear Rate ◽  
Removal Rate ◽  
Polished Surface ◽  
Electrostatic Repulsion ◽  
Polishing Process ◽  
Negative Surface ◽  
Negative Surface Charge ◽  
Slurry Stability

ABSTRACTIn this paper, results of studies on the addition of salt to a polishing slurry, in terms of its effect on slurry stability, SiO2 polishing rate and surface roughness of the polished surface are presented. Three salts, viz. LiCl, NaCl and KCl were selected, and three concentrations were tested. Polishing rate measurements using these slurries show that adding salt leads to increased removal rate without affecting surface roughness significantly. Based on these results, we can say that the agglomerates formed by adding salt to the slurry are fairly soft and easily broken during the polishing process. In addition, turbidity and particle size measurements show that significant coagulation of the particles in the slurry occurs only at the highest salt concentration, and is fastest for LiCl and NaCl, with KCl showing the slowest coagulation. From these results, it can be concluded that the enhancement in polish rate is due to increased contact at the wafer-pad-slurry interface, and not due to formation of larger agglomerated particles in the slurry. This is because of reduced electrostatic repulsion between these three surfaces, due to the screening of their negative surface charge by the metal ions in solution, resulting in a higher wear rate.

Effect of Abrasive Particle Size on Lapping of Sapphire Wafer by Fixed Abrasive Pad

2018 ◽  
Vol 764 ◽  
pp. 106-114
Author(s):  
Jian Bin Wang ◽  
Zhen Li ◽  
Yong Wei Zhu ◽  
Ben Chi Jiang ◽  
Pei Cheng Shi
Keyword(s):  
Particle Size ◽  
Penetration Depth ◽  
Material Removal ◽  
Removal Rate ◽  
Abrasive Particle ◽  
Work Piece ◽  
Average Surface Roughness ◽  
Sapphire Wafer ◽  
Fixed Abrasive Pad ◽  
Fixed Abrasive

The choice of abrasive particle size is crucial to improve the lapping efficiency and surface quality in lapping of sapphire wafer by fixed abrasive (FA) pad. A model for the penetration depth of a single abrasive is developed with fixed abrasive pad. A serious of lapping tests were carried out using FA pads embedded with different size of diamond particles to verify the validity of the developed model. Results show that the penetration depth of abrasive is related not only to the particle size, but to the hardness ratio of the work-piece to the pad as well. The material removal rate of sapphire is proportional to the square of abrasive particle size, while the average surface roughness is proportional to the abrasive particle size.

Diamond Coated End Mills in Machining Silicon Carbide

2012 ◽  
Vol 576 ◽  
pp. 531-534 ◽  
Author(s):  
Mohamed Konneh ◽  
Mohammad Iqbal ◽  
Nik Mohd Azwan Faiz
Keyword(s):  
Surface Roughness ◽  
Silicon Carbide ◽  
High Performance ◽  
Removal Rate ◽  
Roughness Parameter ◽  
Surface Damage ◽  
Ceramic Materials ◽  
Real Problem ◽  
Machining Parameters ◽  
Machining Processes

Silicon Carbide (SiC) is a type of ceramic that belongs to the class of hard and brittle material. Machining of ceramic materials can result in surface alterations including rough surface, cracks, subsurface damage and residual stresses. Efficient milling of high performance ceramic involves the selection of appropriate operating parameters to maximize the material removal rate (MRR) while maintaining the low surface finish and limiting surface damage. SiC being a ceramic material, its machining poses a real problem due to its low fracture toughness, making it very sensitive to crack. The paper discusses milling of silicon carbide using diamond coated end mill under different machining conditions in order to determine the surface roughness parameter, Rt after the machining processes and to establish a relationship between the machining parameters and response variables. Based on the surface roughness carried out the lowest Rt obtained is 0.46 µm.

scholarly journals Effect of the Lapping Platen Groove Density on the Characteristics of Microabrasive-Based Lapping

Micromachines ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 775
Author(s):  
Taekyung Lee ◽  
Haedo Jeong ◽  
Sangjik Lee ◽  
Doyeon Kim ◽  
Hyoungjae Kim
Keyword(s):  
Surface Roughness ◽  
Film Thickness ◽  
Material Removal ◽  
Removal Rate ◽  
High Surface ◽  
Abrasive Particle ◽  
Process Conditions ◽  
Abrasive Particles ◽  
Oil Film ◽  
Process Characteristics

Microabrasive-based lapping is widely used in the manufacturing of single-crystal substrates such as sapphire, SiC, and GaN. Although many studies have been conducted to improve the lapping process characteristics, most of them focused on process conditions or consumables. In this study, the effect of the lapping platen groove density on the lapping characteristics was studied using a sapphire substrate. Groove density was defined as the ratio of groove width to groove pitch, and the displacement of the lapping head was measured to calculate the oil film thickness. It was confirmed that, for groove densities below 0.30, hydroplaning occurs when the oil film thickness increases. When the oil film thickness is larger than the abrasive particle size, the material removal rate is low because the abrasive does not participate in the lapping process. When the oil film was developed, the experimental results showed a high surface roughness and poor flatness of the substrate, as only large abrasive particles participated in the lapping process. Therefore, to improve the lapping characteristics, it is important to reduce the groove density by reducing the groove pitch, which prevents the development of the oil film.

Performance Study of LaPO4-Y2O3 Composite Fabricated by Sol-Gel Process Using Abrasive Waterjet Machining

2019 ◽  
pp. 143-161
Author(s):  
M. Uthayakumar ◽  
Balamurugan Karnan ◽  
Adam Slota ◽  
Jerzy Zajac ◽  
J. Paulo Davim
Keyword(s):  
Surface Roughness ◽  
Silicon Carbide ◽  
Material Removal Rate ◽  
Removal Rate ◽  
Sol Gel ◽  
Abrasive Water Jet ◽  
Lanthanum Phosphate ◽  
Abrasive Water Jet Machining ◽  
Sol Gel Process ◽  
Kerf Angle

This chapter presents an effective approach to assess the abrasive water jet machining of lanthanum phosphate reinforced with yttrium composite. A novel composite is prepared with the mixture of lanthanum phosphate sol and yttrium nitrate hexalate with a ratio of 80/20 by aqueous sol-gel process. Silicon carbide of 80 mesh size is used as abrasive. The effects of each input parameter of abrasive water jet machining are studied with an objective to improve the material removal rate with reduced kerf angle and surface roughness. The observations show that the jet pressure contributes by 77.6% and 45.15% in determining material removal rate and kerf angle, respectively. Through analysis of variance, an equal contribution of jet pressure (38.18%) and traverse speed (40.97%) on surface roughness is recorded. Microscopic examination shows the internal stress developed by silicon carbide which tends to get plastic deformation over the cut surface.

Machining performance evaluation under recently developed sustainable HAJM process of zirconia ceramic using hot SiC abrasives: An experimental and simulation approach

2021 ◽  
pp. 095440622110101
Author(s):  
Subhadip Pradhan ◽  
Sudhansu Ranjan Das ◽  
Pankaj Charan Jena ◽  
Debabrata Dhupal
Keyword(s):  
Surface Roughness ◽  
Silicon Carbide ◽  
Erosion Rate ◽  
Research Work ◽  
Abrasive Particle ◽  
Target Surface ◽  
Zirconia Ceramic ◽  
Surface Erosion ◽  
Vast Number ◽  
Micro Channels

The proposed research work accomplishes the experimental study and computational fluid dynamics (CFD) technique for erosive footprint prediction extent in hot abrasive jet machining (HAJMing) constraints on target surface erosion rate, surface roughness of intricately shaped tapered holes generation. The CFD-obtained footprints were in superior agreement with experimentally measured data. HAJMing process uses a relatively high speed air-hot abrasive stream to produce both high accuracy micro-channels and tapered holes. HAJM also defines itself phenomenal competence over all advanced manufacturing techniques due to its growing demands for better surface reliability with defects (mostly stress, heat) free surfaces. Zirconia is widely accepted and associated in the non-conventional machining processes and industries with the years of track on record of proven performance in a vast number of brittle materials. Most perceptible act in this research is the selection of abrasive particle to achieve the appropriate intricate shaped holes on zirconia ceramic with hot silicon carbide (SiC) abrasives. Machining of these features are done with varying the abrasive temperature. Optical microscopic view was considered for the generation of machined holes during HAJMing. All the experimental data were presented to study the effect of machining constraints on target surface erosion rate and surface roughness using HAJMing. Single impact experiments were executed to measure the target surface erosion due to impact of individual hot silicon carbide abrasive particles. An experimental setup has been designed to conduct the machining trials using Box-Behnken design of experiments. It is also shown that the generated workpiece surface contour and erosion rate are the function of machining constraints which have a negligible influence on air-abrasive flow characteristics. This research work also deals with the sustainability assessment under environmental-friendly hot abrasive-assisted machining conditions.

Low Defect Ceria for ILD CMP

2007 ◽  
Vol 991 ◽  
Author(s):  
Jai Kasthurirangan ◽  
John Parker ◽  
Tiffany Bettis ◽  
Charles Dowell
Keyword(s):  
Particle Size ◽  
Removal Rate ◽  
Abrasive Particle ◽  
Commercial Development ◽  
Particle Properties ◽  
Particle Characteristics ◽  
Particle Population ◽  
Surface Balance ◽  
Simple Surface ◽  
Inverse Proportionality

ABSTRACTThe reduction of wafer scratching is a key goal driving the commercial development of CMP slurries. To better understand the underlying abrasive particle properties critical to the scratch performance of ILD CMP slurries, the scratching behavior of ceria slurries prepared with a range of particle size characteristics are characterized. Scratch results are presented and two effects are proposed to account for the findings. The Removal Rate Effect relies solely on the observed inverse proportionality between scratching and removal rate. This interpretation is consistent with a simple surface balance of scratches but suggests that removal rate differences dominate scratch performance. The Managed Tail Effect considers the effect of particle characteristics on both the creation and the removal of scratches. For a given particle population, the larger particles are assumed to dominate scratch creation. However, larger particles are also seen to drive removal rate which affects the removal of scratches during polishing. This interpretation implies that optimal scratch performance for a ceria ILD CMP slurry will be obtained when the width of the ceria particle's size distribution is optimized relative to its mean.

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