Study on the relationship between laser processing sound and material removal characteristics

Chemical mechanical polishing (CMP) has already become a mainstream technology in global planarization of wafer, but the mechanism of nonuniform material removal has not been revealed. In this paper, the calculation of particle movement tracks on wafer surface was conducted by the motion relationship between the wafer and the polishing pad on a large-sized single head CMP machine. Based on the distribution of particle tracks on wafer surface, the model for the within-wafer-nonuniformity (WIWNU) of material removal was put forward. By the calculation and analysis, the relationship between the motion variables of the CMP machine and the WIWNU of material removal on wafer surface had been derived. This model can be used not only for predicting the WIWNU, but also for providing theoretical guide to the design of CMP equipment, selecting the motion variables of CMP and further understanding the material removal mechanism in wafer CMP.

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Investigation of the Water Guided Laser Micro-Jet Machining of Aero Engine Components

Volume 1: Processes ◽

10.1115/msec2017-2723 ◽

2017 ◽

Author(s):

Zhigang Wang

Keyword(s):

Energy Density ◽

Material Removal ◽

Removal Rate ◽

Cutting Speed ◽

Potential Method ◽

Laser Machining ◽

Aero Engine ◽

Engine Components ◽

The Relationship ◽

Dual Laser

The water guided laser micro-jet (LMJ) is a new potential method to machine aero engine parts with much less heat affected area and faster cutting speed than dry laser machining. The focus of this paper is to investigate the energy density and material removal for a dual-laser LMJ system. Then, the effects of dominated parameters on the energy density of LMJ are analyzed. Finally, a mathematical model is developed to describe the relationship between dominant laser parameters with the energy density of LMJ and material removal rate followed by machining case studies of aero engine components.

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Wear Characteristics of the Sub-Aperture Tools and Material Removal Rate in Precision Grinding with Loose Abrasives

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.329.69 ◽

2007 ◽

Vol 329 ◽

pp. 69-74

Author(s):

H. Cheng ◽

H.Y. Tam ◽

Y. Gao ◽

Yong Bo Wu ◽

Y. Wang

Keyword(s):

Material Removal Rate ◽

Material Removal ◽

High Efficiency ◽

Removal Rate ◽

Process Analysis ◽

Actual Process ◽

Correlative Function ◽

Glass Specimen ◽

Grinding Tool ◽

The Relationship

This paper proposes a sub-aperture grinding tool for loose abrasive computer controlled surfacing, which is designed to perform epicyclic motion and rotate around its centre at a rapid rate, whilst the entire mechanism revolves around a secondary centre at a slower rate. In actual process, the wear of the tool could affect the material removal function, and make the process unstable, thus in fact, it is difficult to make a deterministic manufacturing. The focus of the present paper is on wearing characteristics of sub-aperture tools and the wear evenness as the main objectives. To make a further study, material removal function of the tool is firstly established through theoretically modelling, next, a correlative function with weighted factors is built, which is suitable for specifying the wearing degree of the tool. Finally, to discover the relationship between the material removal rate and the tool wearing characteristics, and to optimize the grinding process, analysis and experiments are then carried out on a K9 glass specimen by means of three kinds of tool materials, i.e., polyurethane pad, aluminum plate and pitch based on the proposed technique and model. The results indicated that the required high efficiency and precision could be achieved by choosing proper processes.

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Research on the Machining Performance of SiC/Al Composites Utilizing the BEAM Process

Volume 1: Processing ◽

10.1115/msec2015-9301 ◽

2015 ◽

Cited By ~ 2

Author(s):

Jipeng Chen ◽

Lin Gu ◽

Hui Xu ◽

Wansheng Zhao

Keyword(s):

Material Removal ◽

Removal Rate ◽

Machining Efficiency ◽

Machining Performance ◽

Peak Current ◽

Tool Wear Ratio ◽

Large Peak ◽

Performance Results ◽

The Relationship ◽

Blasting Erosion Arc Machining

The Blasting Erosion Arc Machining (BEAM) process was applied to improve the machining efficiency of SiC/Al composites. A set of experiments were conducted on 20 vol% SiC/Al composites to find out the relationship between the parameters and machining performance. Results revealed that when the peak current was 500 A, the material removal rate (MRR) could be greater than 8,200 mm3/min and the tool wear ratio (TWR) was about 2%. Besides, the influence of polarity on the surface properties was also studied by using scanning electron microscope (SEM) and metalloscope. It disclosed that machining with a large peak current and a negative BEAM is suitable for bulk mass material removal, while the surface quality could be improved by applying the positive BEAM. Finally, a machined sample demonstrated the fesibility of BEAM for the machining of SiC/Al materials.

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Estimation of Material Removal by Profilometer Measurements in Mass Finishing

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.611-612.615 ◽

2014 ◽

Vol 611-612 ◽

pp. 615-622

Author(s):

Luana Bottini ◽

Alberto Boschetto ◽

Francesco Veniali

Keyword(s):

Plastic Deformation ◽

Surface Modification ◽

Surface Morphology ◽

Process Parameters ◽

Material Removal ◽

Machining Process ◽

Local Surface ◽

Mass Finishing ◽

Barrel Finishing ◽

The Relationship

This paper presents a new procedure to estimate the material removal (MR) in such conditions or operations where small amount of material or wear occur. The monitoring of material removal is essential to understand the machining mechanisms of several processes such as super finishing ones. For example the study of some mass finishing (MF) operations, i. e. the barrel finishing (BF) and the spindle finishing (SF), have been always limited by the difficulty to measure the local surface modification. Thus there is no knowledge about the relationship between process parameters and obtainable surface quality. The procedure is based on profilometer measurements typically used to characterized local surface morphology. An algorithm automatically finds the most representative peak of the profile. The comparison between the Abbot-Firestone curves, related to peaks achieved in different condition, permits to measure the volume of material removed by the operation. This method overcomes the well-known problem to repositioning the instrument in the same place when the part is moved from machining process to measurement one. In the case of BF, experimental demonstrated the reliability of this methodology to provide the evolution of material removed as a function of working time. Moreover the graphical plot of the representative peak at different times gave important information about machining mechanism. In particular it allowed to verify assumptions regarding the plastic deformation and the peak cutting which takes place.

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The Influence of the Grinding Force to the Material Removal Rate in the Heavy Load Honing

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.63-64.719 ◽

2011 ◽

Vol 63-64 ◽

pp. 719-722

Author(s):

Jian Ye Guo ◽

Chao Yu ◽

Guang Qi Cai

Keyword(s):

Mathematical Model ◽

Material Removal Rate ◽

Material Removal ◽

Removal Rate ◽

Grinding Force ◽

Processing Technology ◽

Heavy Load ◽

Theoretical Significance ◽

The Mathematical Model ◽

The Relationship

This paper took the grinding force in the heavy load honing as the object to research, it mainly analyzed the influence of the grinding force to the material removal rate. First the mathematical model of grinding force was established from starting with the honing pressure. Then the mathematical model of material removal rate was established according to the relationship between material removal volume and honing pressure. Finally the influence of the honing pressure to the material removal rate was analyzed with the aid of software. The results of this paper have important theoretical significance to optimize the processing technology of heavy load honing and further enhance the machining precision and the honing efficiency.

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Material Removal Rate of Double-faced Mechanical Polishing of 4H-SiC Substrate

10.21203/rs.3.rs-431712/v1 ◽

2021 ◽

Author(s):

Peng Zhang ◽

Jingfang Yang ◽

Huadong Qiu

Keyword(s):

Material Removal Rate ◽

Material Removal ◽

Removal Rate ◽

Mechanical Polishing ◽

Ring Gear ◽

The Third ◽

Regression Test ◽

Polishing Pads ◽

The Relationship

Abstract Silicon carbide (SiC) has been a promising the-third-generation semiconductor power device material for high-power, high-temperature, substrate applications. It aims to improve the material removal rate (MRR), on the premise of ensuring the surface roughness requirements of the double-faced mechanical polishing of 6-inch SiC substrate. To obtain the relationship between any point on SiC substrate and polishing pads, the model about double-faced mechanical polishing has been built and the kinematics equations were created. Best optimized material removal rate parameters were obtained. MRR reached the maximum when speed rate of the outside ring gear to the inside sun gear m=-1, speed rate of lower plate to the inside sun gear n=5, SiC substrate distribution radius RB=75. The primary and secondary order of MRR (n>m>RB) was obtained. An accurate mathematical model of orthogonal rotary regression test of Tri-factor quadratic of MRR was established and the regression model was significant. Surface quality of SiC substrate was observed and characterized with SEM and AFM. It greatly provides a key guarantee for the next process of CMP, confirmed the importance of MRR to ultra-smooth polishing, and provides a guarantee for its application in semiconductor equipment and technology.

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A Comparative Study of Machining Parameters on Die-Sinking Electrical Discharge Machining (EDM) using Copper and Aluminium Electrodes on Hard Steels

International Journal of Materials Forming and Machining Processes ◽

10.4018/ijmfmp.2016010103 ◽

2016 ◽

Vol 3 (1) ◽

pp. 22-44 ◽

Cited By ~ 1

Author(s):

Ashwani Kharola

Keyword(s):

Surface Roughness ◽

Discharge Current ◽

Electrical Discharge ◽

Material Removal ◽

Electrical Discharge Machining ◽

Removal Rate ◽

Depth Of Cut ◽

Machining Parameters ◽

Die Steel ◽

The Relationship

This paper considers effect of variation in value of Discharge current on different process parameters of Die Sinking EDM. The parameters considered were Material removal rate (MRR), Tool removal rate (TRR), Surface roughness (Ra) and Time (for machining required depth of cut). A total of 32 experiments were conducted on four different hard steels i.e. Die steel D3, En-8, En-19 and Stainless steel (SS-AISI-440C). The Copper and Aluminium electrodes brazed with mild steel were used for machining. The four different values of current i.e. 6A, 9A, 12A and 15A were considered for the study. The experimental results shows the relationship between MRR, TRR, Ra and Time with variation in magnitude of discharge current. This study also illustrates the relationship among different process parameter considered in the study. The results are shown with the help of graphs and tables.

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Novel three-body nano-abrasive wear mechanism

Friction ◽

10.1007/s40544-020-0481-1 ◽

2021 ◽

Author(s):

Ruling Chen ◽

Shaoxian Li

Keyword(s):

Abrasive Wear ◽

Material Removal ◽

Crystalline Silicon ◽

Surface Damage ◽

Mating Surface ◽

Dynamics Simulations ◽

New Research ◽

Three Body ◽

The Relationship ◽

Material Wear

AbstractCurrent three-body abrasive wear theories are based on a macroscale abrasive indentation process, and these theories claim that material wear cannot be achieved without damaging the hard mating surface. In this study, the process of three-body nano-abrasive wear of a system including a single crystalline silicon substrate, an amorphous silica cluster, and a polyurethane pad, based on a chemical mechanical polishing (CMP) process, is investigated via molecular dynamics simulations. The cluster slid in a suspended state in smooth regions and underwent rolling impact in the asperity regions of the silicon surface, realizing non-damaging monoatomic material removal. This proves that indentation-plowing is not necessary when performing CMP material removal. Therefore, a non-indentation rolling-sliding adhesion theory for three-body nano-abrasive wear between ultrasoft/hard mating surfaces is proposed. This wear theory not only unifies current mainstream CMP material removal theories, but also clarifies that monoatomic material wear without damage can be realized when the indentation depth is less than zero, thereby perfecting the relationship between material wear and surface damage. These results provide new understanding regarding the CMP microscopic material removal mechanism as well as new research avenues for three-body abrasive wear theory at the monoatomic scale.

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Laser Processing of Silica Aerogels Using Ultrashort Pulses

10.1115/imece2000-1477 ◽

2000 ◽

Author(s):

J. Sun ◽

J. P. Longtin ◽

P. M. Norris

Keyword(s):

Laser Processing ◽

Material Removal ◽

Removal Rate ◽

High Surface ◽

Laser System ◽

High Surface Area ◽

Ultrashort Pulses ◽

Silica Aerogels ◽

Ultrafast Laser ◽

Breakdown Threshold

Abstract Silica aerogels are unique nanostructured materials that possess many distinctive qualities, including extremely low densities and thermal conductivities, very high surface-area-to-volume ratios, and large strength-to-weight ratios. Aerogels, however, are very brittle, and are not readily shaped using traditional machining operations. Ultrafast laser processing may provide an alternative for precision shaping and machining of these materials. This paper discusses investigations of ultrafast laser machining of aerogels for material removal and micromachining. The advantages of ultrafast laser processing include a minimal thermal penetration region and low processing temperatures, precision removal of material, and good-quality feature definition. In this work, an amplified femtosecond Ti:sapphire laser system is used to investigate the breakdown threshold, material removal rate, and specific issues associated with laser processing of aerogels, as well as recommendations for further investigations for these unique materials.

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