scholarly journals Removal Characteristics of Sapphire Lapping using Composite Plates with Consciously Patterned Resinoid-Bonded Semifixed Diamond Grits

Crystals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 293 ◽  
Author(s):  
Wenshan Wang ◽  
Yiqing Yu ◽  
Zhongwei Hu ◽  
Congfu Fang ◽  
Jing Lu ◽  
...  
Keyword(s):  
Material Removal Rate ◽  
Material Removal ◽  
Removal Rate ◽  
Sol Gel ◽  
High Hardness ◽  
Dimensional Accuracy ◽  
Composite Plates ◽  
Thickness Variation ◽  
Total Thickness Variation ◽  
Abrasive Tools

Sapphire lapping is of key importance for the successful planarization of wafers that are widely present in electronic devices. However, the high hardness of sapphire makes it extremely challenging to improve its material removal rate during the lapping process without compromising surface quality and dimensional accuracy. In this work, a novel composite lapping plate consisting of a rigid resin frame and flexible sol–gel balls was fabricated with consciously designed patterns. Through lapping experiment, it was revealed that the diamond grits imbedded in the sol–gel balls can effectively lap the sapphire at a promising material removal rate (MRR), without the formation of undesirable scratches and loss of surface integrity. Moreover, by designing the arrangement patterns of sol–gel balls, the total thickness variation (TTV) can also be ensured for lapped sapphire substrates. The implications of experimental results were also discussed based on the trajectory analysis and contact mechanics of lapping grits in order to demonstrate the potential of the newly developed composite abrasive tools for sapphire-lapping applications.

OPTIMASI PARAMETER PEMESINAN WIRE ELECTRIC DISCHARGE MACHINING BAJA PERKAKAS SKD 11 MENGGUNAKAN METODE TAGUCHI

ROTOR ◽  
2018 ◽  
Vol 11 (2) ◽  
pp. 33
Author(s):  
Setiawan Okik Aris ◽  
Djumhariyanto Dwi ◽  
Mulyadi Santoso
Keyword(s):  
Material Removal Rate ◽  
Material Removal ◽  
Manufacturing Industry ◽  
Removal Rate ◽  
Dimensional Accuracy ◽  
Current Strength ◽  
Influential Factor ◽  
Hard Material ◽  
Taguchi Optimization ◽  
The Wire

EDM wire is one of the non-conventional machinings that is currently widely used in the manufacturing industry because it can process workpieces with hard material and also produces excellent dimensional accuracy. This research was carried out with variable current, voltage and wire speed processes. While the response variable is the material removal rate and cutting width (kerf), this study aims to determine the effect of each factor on each response as well as on the combined response and to find the right combination of parameters to produce optimal response values. The results of the study stated that the current strong factor contributed 89.84% and the wire speed factor was 8.26% against the cutting width response (kerf). The current strong element contributes 87.88% to the material removal rate response. As for the combined response, the influential factor was wire speed with a contribution of 92.79%. The optimal combination of parameters in the combined response is 7 amperes, 5 volts and 10 m / s wire speed. The conclusion of this study informs that the smaller the current strength, the better the value of the cutting width, while the more significant the current force will result in a higher removal rate material. The factor that influences the combined response is wire speed, where the increase in the value of the wire speed increases the amount of the Gray Relational Grade from the combined response. Keywords: Wire EDM, SKD 11 Steel, Taguchi, Optimization

Parametric Optimization of EN-31 Steel in Wire Cut Electro Discharge Machining by Taguchi Technique

2020 ◽  
Vol 12 (7) ◽  
pp. 881-887
Author(s):  
Sahil Sharma ◽  
Umesh Kumar Vates ◽  
Amit Bansal
Keyword(s):  
Material Removal Rate ◽  
Automobile Industry ◽  
Material Removal ◽  
Removal Rate ◽  
Dimensional Accuracy ◽  
Work Piece ◽  
Electro Discharge Machining ◽  
En 31 ◽  
The Impact ◽  
Dies And Moulds

Amongst the various methods of machining, Electro Discharge Machining is the convenient alternatives for the industries due to non-contact of work piece and tool. In the study of various EDM processes the main target is to achieve the better finish of surface, high material removal rate and good dimensional accuracy by regulating the different input parameters. There are various applications of EDM such as aerospace parts, medical equipments, dies and moulds, nuclear and automobile industry. In this experimental study, a trial has made to look the impact of input factors like pulse-on, pulse-off, peak current, tension of wire on rate of material removal, gap current and time for machining. Taguchi (L9 OA) and Analysis of Variance technique were used to optimize the outcomes for wire cut EDM of EN-31 tool steel. The outcomes revealed that Ton and Toff are the leading cogent factor for material removal rate and gap current respectively.

Experimental Study of Lapping Using Mixed Abrasive Grits

2009 ◽  
Author(s):  
Chunhui Chung ◽  
Glenn Melendez ◽  
Imin Kao
Keyword(s):  
Surface Roughness ◽  
Surface Quality ◽  
Material Removal Rate ◽  
Material Removal ◽  
Removal Rate ◽  
Wafer Surface ◽  
Thickness Variation ◽  
Parameter Study ◽  
Manufacturing Processes ◽  
Mixing Ratios

Wafers made of materials such as silicon, III-V and II-VI compounds, and optoelectronic materials, require high-degree of surface quality in order to increase the yield in micro-electronics fabrication to produce IC chips and devices. Measures of properties of surface quality of wafers include: nanotopography, surface morphology, global planarization, total thickness variation (TTV) and warp. Due to the reduction of feature size in micro-electronics fabrication, the requirements of such properties become more and more stringent. To meet such requirements, the wafer manufacturing processes of brittle semiconductor materials, such as slicing, lapping, grinding, and polishing have been continually improved. In this paper, the lapping process of wafer surface treatment is studied with experimental results of surface roughness and material removal rate. In order to improve the performance of lapping process, effects of mixed abrasive grits in the slurry of the free abrasive machining (FAM) processes are studied using a single-sided wafer-lapping machine. Under the same slurry density, experiments employing different mixing ratios of large and small abrasive grits, and various normal loadings on the wafer surface applied through a jig are conducted for parameter study. With various mixing ratios and loadings, observations and measurements such as the total amount of material removed, material removal rate, surface roughness, and relative angular velocity are presented and discussed in this paper. The experiments show that the half-half mixing ratio of abrasives removes more material than other mixing ratios under the same conditions, but with a higher surface roughness. The results of this study can provide a good reference to the FAM processes that practitioners use today by exploiting different mixing ratios and loadings of abrasive slurry in the manufacturing processes.

scholarly journals Experimental investigation and optimization of wall deflection and material removal rate in milling thin-wall parts

2021 ◽  
Vol 8 ◽  
pp. 17
Author(s):  
Gururaj Bolar ◽  
Shrikrishna Nandkishor Joshi
Keyword(s):  
Process Parameters ◽  
Material Removal Rate ◽  
Material Removal ◽  
Removal Rate ◽  
Dimensional Accuracy ◽  
Depth Of Cut ◽  
Thin Wall ◽  
Wall Deflection ◽  
Radial Depth ◽  
Tool Diameter

The selection of optimal process parameters is essential while machining thin-wall parts since it influences the quality of the product and affects productivity. Dimensional accuracy affects the product quality, whereas the material removal rate alters the process productivity. Therefore, the study investigated the effect of tool diameter, feed per tooth, axial and radial depth of cut on wall deflection, and material removal rate. The selected process parameters were found to significantly influence the in-process deflection and thickness deviation due to the generation of unfavorable cutting forces. Further, an increase in the material removal rate resulted in chatter, thus adversely affecting the surface quality during the final stages of machining. Considering the conflicting nature of the two performance measures, Non-dominated Sorting Genetic Algorithm-II was adopted to solve the multi-objective optimization problem. The developed model could predict the optimal combination of process variables needed to lower the in-process wall deflection and maintain a superior surface finish while maintaining a steady material removal rate.

scholarly journals A Role of cryogenic in Wire cut EDM process

2020 ◽  
Vol 184 ◽  
pp. 01067
Author(s):  
Kosaraju Satynarayana ◽  
Kumkuma Rajkiran ◽  
Pujari Anil kumar ◽  
D Chakradhar
Keyword(s):  
Surface Roughness ◽  
Material Removal Rate ◽  
Material Removal ◽  
Removal Rate ◽  
Dimensional Accuracy ◽  
Performance Characteristics ◽  
Machining Processes ◽  
Current Voltage ◽  
Tension Wire ◽  
Wedm Process

Novel techniques are being focused on the enrichment of the performance characteristics under different machining processes. Cryogenic is one of such novel practices that tunes the surface integrity with vast variations with the traditional machining processes. Dimensional accuracy, surface roughness, material removal rate with less reduction in scrap of material is one of the prior targets of production process. Wire cut Electro Discharge Machining (WEDM) is one method that satisfy with upgrading performance characteristics. In order to step-up these performance characteristics in attaining superior quality, cryogenics practices have collaborated with the WEDM process. Present paper deals with the reviews of the researchers that have been performed over cryogenic treated WEDM process. Effect of performance characteristics like pulse on, pulse off, current, voltage, wire tension, wire feed is discussed with relation to material removal rate, tool wear rate and surface roughness evolved. Key concept of paper is to include the research ideology with best feasible techniques that can prevail in production practice in order of contribute to the forthcoming researches in industrial and production departments.

Modeling and Analysis of Material Removal Characteristics in Silicon Wafer Double Side Polishing

2012 ◽  
Vol 516 ◽  
pp. 384-389
Author(s):  
Sang Jik Lee ◽  
Hyoung Jae Kim ◽  
Hae Do Jeong
Keyword(s):  
Integrated Circuits ◽  
Process Parameters ◽  
Material Removal Rate ◽  
Material Removal ◽  
Removal Rate ◽  
Thickness Variation ◽  
Modeling And Analysis ◽  
Profile Variation ◽  
Friction Energy ◽  
Wafer Edge

As advancing technologies increase the demand for yield and planarity in integrated circuits, wafers have become larger and their specifications more stringent. Flatness, thickness variation and nanotopography have emerged as important concerns in the wafering process. Double side polishing has been adopted as a solution to these problems. This paper focuses on the material removal characteristics and wafer profile variation during Si double side polishing. A polishing experiment to investigate Si removal characteristics according to process parameters was carried out in a single head rotary polisher equipped with a monitoring system for friction force. It was found that the material removal rate is related to friction energy rate, and the polishing state was transited and divided into three conditions according to pressure. On the basis of the experimental results, the wafer profile variation in double side polishing was modelled and simulated according to pressure. The friction energy was calculated to find the material removal amount across the wafer. With the conversion of calculated friction energy to the material removal amount, wafer profile variation was simulated. As a result, the wafer profile variation and its range were increased with a pressure increase, and originated from the position near the wafer edge.

scholarly journals The Methodologies Adopted To Improve the Machinability in Die-Sinking EDM

2019 ◽  
Vol 9 (1S4) ◽  
pp. 645-647
Keyword(s):  
Tool Wear ◽  
Material Removal Rate ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
High Surface ◽  
High Hardness ◽  
Machining Process ◽  
Work Piece ◽  
Machining Processes

Electrical discharge machining (EDM) is one of the oldest nontraditional machining processes, commonly used in automotive, aerospace and ship building industries for machining metals that have high hardness, strength and to make complicated shapes that cannot be produced by traditional machining techniques. The process is based on the thermoelectric energy between the work piece and an electrode. EDM is slow compared to conventional machining, low material removal rate, high surface roughness, high tool wear and formation of recast layer are the main disadvantages of the process. Tool wear rate, material removal rate and surface quality are important performance measures in electric discharge machining process. Numbers of ways are explored by researchers for improving and optimizing the output responses of EDM process. The paper summarizes the research on die-sinking EDM relating to the improvements in the output response.

scholarly journals Microchannels Fabrication in Alumina Ceramic Using Direct Nd:YAG Laser Writing

Micromachines ◽  
2018 ◽  
Vol 9 (8) ◽  
pp. 371 ◽  
Author(s):  
Muneer Mohammed ◽  
Usama Umer ◽  
Ateekh Rehman ◽  
Abdulrahman Al-Ahmari ◽  
Abdulaziz El-Tamimi
Keyword(s):  
Laser Beam ◽  
Process Parameters ◽  
Material Removal Rate ◽  
Nd:Yag Laser ◽  
Material Removal ◽  
Removal Rate ◽  
Dimensional Accuracy ◽  
Alumina Ceramic ◽  
Beam Intensity ◽  
Laser Writing

Ceramic microchannels have important applications in different microscale systems like microreactors, microfluidic devices and microchemical systems. However, ceramics are considered difficult to manufacture owing to their wear and heat resistance capabilities. In this study, microchannels are developed in alumina ceramic using direct Nd:YAG laser writing. The laser beam with a characteristic pulse width of 10 µs and a beam spot diameter of 30 µm is used to make 200 µm width microchannels with different depths. The effects of laser beam intensity and pulse overlaps on dimensional accuracy and material removal rate have been investigated using different scanning patterns. It is found that beam intensity has a major influence on dimensional accuracy and material removal rate. Optimum parameter settings are found using grey relational grade analysis. It is concluded that low intensity and low to medium pulse overlap should be used for better dimensional accuracy. This study facilitates further understanding of laser material interaction for different process parameters and presents optimum laser process parameters for the fabrication of microchannel in alumina ceramic.

Electro Discharge Machining of AL2O3 Based Ceramic

2014 ◽  
Vol 625 ◽  
pp. 511-517
Author(s):  
S.K. Elmenshawy ◽  
Mohammad A. Younes ◽  
Hassan El-Hofy
Keyword(s):  
Performance Measures ◽  
Material Removal Rate ◽  
Material Removal ◽  
Removal Rate ◽  
High Hardness ◽  
Crater Diameter ◽  
Average Roughness ◽  
Electro Discharge Machining ◽  
Complex Shapes ◽  
Pulse On Time

Products such as parts of die sets and cutting tool inserts are normally produced with complex shapes in materials of high hardness and wear resistance such as ceramics. Electro discharge machining (EDM) can be used to manufacture complex shapes in high hardness materials, but the material should be conductive. Being conductive, Aluminum oxide (Al2O3) based ceramics represent a good alternative for manufacturing hard complex shape parts. However, the integrity of the produced surfaces and the material removal rate need to be investigated. A full factorial experimental design was used to investigate the effect of some selected process variables, namely; pulse-on time, pulse-off time, and pulse current on specific EDM performance measures. The considered performance measures are; crater diameter (D), material removal rate (MRR), and average roughness value (Ra). An analysis of variance (ANOVA) test was carried out to evaluate the experimental results. Empirical models have been developed using DESIGN EXPERT V.8 to predict the average crater diameter (D), material removal rate (MMR), and average roughness value (Ra). Machining conditions that should result in optimum process performance measures have also been considered.

scholarly journals Material Removal Model for Lapping Process Based on Spiral Groove Density

2021 ◽  
Vol 11 (9) ◽  
pp. 3950
Author(s):  
Taekyung Lee ◽  
Haedo Jeong ◽  
Sangjik Lee ◽  
Hanchul Cho ◽  
Doyeon Kim ◽  
...  
Keyword(s):  
Material Removal Rate ◽  
Material Removal ◽  
Removal Rate ◽  
Thickness Variation ◽  
Contact Interface ◽  
Spiral Groove ◽  
Lubrication Condition ◽  
Material Removal Model ◽  
Increasing Demand ◽  
Removal Model

The increasing demand for single-crystal wafers combined with the increase in diameter of semiconductor wafers has warranted further improvements in thickness variation and material removal rate during lapping to ensure price competitiveness of wafers; consequently, the lapping process has gained the attention of researchers. However, there is insufficient research on the effect of platen grooves on the lapping process. In this study, the parameters to describe grooves were defined in order to understand their influence on the lapping process, and a material removal model was suggested based on indentation theory and subsequently experimentally validated. The results indicate that changes in groove density affect the lubrication condition at the contact interface as well as the probability of abrasive participation by varying the oil film thickness. When fabricating the groove for a lapping platen, a groove density at the critical groove density (CGD) or higher should be selected. The higher the groove density, the easier it is to avoid the CGD, and the higher is the material removal rate. The results of this study will enable engineers to design lapping platen grooves that are suitable for the production of modern semiconductor wafers.

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