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1

An on-line monitoring system for a micro electrical discharge machining (micro-EDM) process  

NASA Astrophysics Data System (ADS)

A pulse-type discriminating system to monitor the process of micro electrical discharge machining (micro-EDM) is developed and implemented. The specific features are extracted and the pulses from a RC-type power source are classified into normal, effective arc, transient short circuit and complex types. An approach to discriminate the pulse type according to three durations measured at three pre-determined voltage levels of a pulse is proposed. The developed system is verified by using simulated signals. Discrimination of the pulse trains in actual machining processes shows that the pulses are mainly the normal type for micro wire-EDM and micro-EDM milling. The pulse-type distribution varies during the micro-EDM drilling process. The percentage of complex-type pulse increases monotonically with the drilling depth. It starts to drop when the gap condition is seriously deteriorated. Accordingly, an on-line monitoring strategy for the micro-EDM drilling process is proposed.

Liao, Y. S.; Chang, T. Y.; Chuang, T. J.

2008-03-01

2

QU, JUN. Development of Cylindrical Wire Electrical Discharge Machining Process and Investigation of Surface Integrity and Mechanical Property of EDM Surface  

E-print Network

J. Shih) The cylindrical wire Electrical Discharge Machining (EDM) process was developed to generate-resistant underwater rotary spindle was designed and added to a conventional two-axis wire EDM machine to enable be achieved in the cylindrical wire EDM than the 2D wire EDM. Effects of some key process parameters, wire

Shih, Albert J.

3

Modeling and optimizing electrodischarge machine process (EDM) with an approach based on genetic algorithm  

NASA Astrophysics Data System (ADS)

Electro Discharge Machine (EDM) is the commonest untraditional method of production for forming metals and the Non-Oxide ceramics. The increase of smoothness, the increase of the remove of filings, and also the decrease of proportional erosion tool has an important role in this machining. That is directly related to the choosing of input parameters.The complicated and non-linear nature of EDM has made the process impossible with usual and classic method. So far, some methods have been used based on intelligence to optimize this process. At the top of them we can mention artificial neural network that has modelled the process as a black box. The problem of this kind of machining is seen when a workpiece is composited of the collection of carbon-based materials such as silicon carbide. In this article, besides using the new method of mono-pulse technical of EDM, we design a fuzzy neural network and model it. Then the genetic algorithm is used to find the optimal inputs of machine. In our research, workpiece is a Non-Oxide metal called silicon carbide. That makes the control process more difficult. At last, the results are compared with the previous methods.

Zabbah, Iman

2011-12-01

4

Modeling and optimizing electrodischarge machine process (EDM) with an approach based on genetic algorithm  

NASA Astrophysics Data System (ADS)

Electro Discharge Machine (EDM) is the commonest untraditional method of production for forming metals and the Non-Oxide ceramics. The increase of smoothness, the increase of the remove of filings, and also the decrease of proportional erosion tool has an important role in this machining. That is directly related to the choosing of input parameters.The complicated and non-linear nature of EDM has made the process impossible with usual and classic method. So far, some methods have been used based on intelligence to optimize this process. At the top of them we can mention artificial neural network that has modelled the process as a black box. The problem of this kind of machining is seen when a workpiece is composited of the collection of carbon-based materials such as silicon carbide. In this article, besides using the new method of mono-pulse technical of EDM, we design a fuzzy neural network and model it. Then the genetic algorithm is used to find the optimal inputs of machine. In our research, workpiece is a Non-Oxide metal called silicon carbide. That makes the control process more difficult. At last, the results are compared with the previous methods.

Zabbah, Iman

2012-01-01

5

Analysis of aerosol emission and hazard evaluation of electrical discharge machining (EDM) process.  

PubMed

The safety and environmental aspects of a manufacturing process are important due to increased environmental regulations and life quality. In this paper, the concentration of aerosols in the breathing zone of the operator of Electrical Discharge Machining (EDM), a commonly used non traditional manufacturing process is presented. The pattern of aerosol emissions from this process with varying process parameters such as peak current, pulse duration, dielectric flushing pressure and the level of dielectric was evaluated. Further, the HAZOP technique was employed to identify the inherent safety aspects and fire risk of the EDM process under different working conditions. The analysis of aerosol exposure showed that the concentration of aerosol was increased with increase in the peak current, pulse duration and dielectric level and was decreased with increase in the flushing pressure. It was also found that at higher values of peak current (7A) and pulse duration (520 micros), the concentration of aerosols at breathing zone of the operator was above the permissible exposure limit value for respirable particulates (5 mg/m(3)). HAZOP study of the EDM process showed that this process is vulnerable to fire and explosion hazards. A detailed discussion on preventing the fire and explosion hazard is presented in this paper. The emission and risk of fire of the EDM process can be minimized by selecting proper process parameters and employing appropriate control strategy. PMID:20720340

Jose, Mathew; Sivapirakasam, S P; Surianarayanan, M

2010-01-01

6

TECHNICAL NOTE: Fabrication of microelectrodes for EDM machining by a combined etching process  

NASA Astrophysics Data System (ADS)

In this note, multi-headed microelectrodes were machined by a combined sequence process of WEDG, ultrasonic-aided chemical etching and an electrochemical anodic etching procedure. Electrodes were cut to 0.1 mm by a wire EDM machine from an original diameter of 3 mm in the first step. Electrodes were continually machined by chemical etching and anodic electrochemical etching. During electrolysis, copper impurity produced on the anode is not easily removed from its matrix. A ultrasonic mechanism was utilized to agitate the ferric chloride solution to clean the surface impurity off the electrode. The performance of ultrasonic-aided chemical etching was also studied. Micro single electrodes and foil electrodes were processed by chemical etching. Multi-headed microelectrodes can be machined to 30 m by the combined sequence etching technology proposed.

Weng, Feng-Tsai

2004-05-01

7

State of the art electrical discharge machining (EDM)  

Microsoft Academic Search

Electrical discharge machining (EDM) is a well-established machining option for manufacturing geometrically complex or hard material parts that are extremely difficult-to-machine by conventional machining processes. The non-contact machining technique has been continuously evolving from a mere tool and die making process to a micro-scale application machining alternative attracting a significant amount of research interests.In recent years, EDM researchers have explored

K. H Ho; S. T Newman

2003-01-01

8

Development of a reversible machining method for fabrication of microstructures by using micro-EDM  

Microsoft Academic Search

A new micromachining method for the fabrication of micro-metal structures by using micro-reversible electrical discharge machining (EDM) was investigated. The reversible machining combines the micro-EDM deposition process with the selective removal process, which provides the ability of depositing or removing metal material using the same micro-EDM machining system. From the discharge mechanism of micro-EDM, the process conditions of micro-EDM deposition

Zilong Peng; Zhenlong Wang; Yinghuai Dong; Hui Chen

2010-01-01

9

A fatigue study of electrical discharge machine (EDM) strain-gage balance materials  

Microsoft Academic Search

A fatigue study was undertaken to determine how much the electrical discharge machine (EDM) process affected the fatigue life of balance materials by comparing EDM and regular milling machine samples. Simulation of a typical balance stress configuration was devised for the fatigue testing in order to obtain results more closely related to balance situations. The fatigue testing of the EDM

Ray D. Rhew

1989-01-01

10

Modeling of the Discharge-Sample Interaction in the Electron Discharge Machining (EDM) Process  

Microsoft Academic Search

Summary form only given. We present a global model of the discharge-sample interaction in the EDM environment. Using this model, important quantities that are of crucial importance for the development of EDM like the microstructure and the residual stress in the resolidified layer as well as the mass transfer controlling the erosion rate can be calculated accurately. A thermal model

B. Revaz; G. Witz; R. Flukiger; J. Carron; M. Rappaz

2005-01-01

11

3D micro-EDM machining technique  

NASA Astrophysics Data System (ADS)

The micro-EDM machining technique has been broadly applied to fabricate 2D and 3D micro-parts. It is difficult to produce a metal mold with dimension from several micrometers and with the accuracy in the level of micrometers . Poor accuracy comes from electrode wear during 3D micro-EDM machining. In this research, an efficient wear compensation cooperated with CAD/CAM path compensation is provided to improve the machining accuracy. In the experiments, by fabricating a micro-gear and sculpturing letters on surface of tiny steel ball, the technique provided in this research shows the expected results successfully.

Kuo, Chia-Lung; Chen, Shung-Tong; Wu, Ying-Jeng E.; Yen, Albert T.

1997-11-01

12

New technologies and applications of EDM process  

Microsoft Academic Search

Within the Faculty of Machine Building from the Technical University of Cluj-Napoca, Romania unconventional technologies researches\\u000a were performed for 20 years. The team focused on national research projects referring to micro machining and special applications.\\u000a EDM process (Electric Discharge Machining) has a great importance to the industry. Even if it never be able to compete with\\u000a the metal cutting manufacturing

Marcel Sabin Popa; Glad Contiu; Grigore Pop; Preja Dan

2009-01-01

13

Process capabilities of Micro-EDM and its applications  

Microsoft Academic Search

The micro-electrical discharge machining (micro-EDM) process has proved to be an appropriate nonconventional machining method\\u000a for manufacturing accurate and complex three-dimensional structural micro-features which are difficult to be produced by conventional\\u000a processes. However, the miniaturisation of the EDM process requests special requirements on the machining equipment. Pulse\\u000a generators which can produce small input energy pulses and high precision systems are

Kun Liu; Bert Lauwers; Dominiek Reynaerts

2010-01-01

14

A review on current research trends in electrical discharge machining (EDM)  

Microsoft Academic Search

Electrical discharge machining (EDM) is one of the earliest non-traditional machining processes. EDM process is based on thermoelectric energy between the work piece and an electrode. A pulse discharge occurs in a small gap between the work piece and the electrode and removes the unwanted material from the parent metal through melting and vaporising. The electrode and the work piece

Norliana Mohd Abbas; Darius G. Solomon

2007-01-01

15

Study on ultra-fine w-EDM with on-machine measurement-assisted  

Microsoft Academic Search

The purpose of this study was to develop the on-machine measurement techniques so as to precisely fabricate micro intricate part using ultra-fine w-EDM. The measurement-assisted approach which employs an automatic optical inspection (AOI) is incorporated to ultra-fine w-EDM process to on-machine detect the machining error for next re-machining. The AOI acquires the image through a high resolution CCD device from

Shun-Tong Chen; Hong-Ye Yang

2011-01-01

16

FANUC Wire EDM Machine 100% Built in Japan  

E-print Network

FANUC Wire EDM Machine Alpha 0iE 100% Built in Japan #12;Features of the Alpha iE Series Ai Pulse://www.youtube.com/watch?v=jeDggDPepUY Cut Monitor 2 with live remote part graphics (standard) All Fanuc Wire EDMs comes standard with standard brass wire. Fanuc EDMs do not need expensive oversized coated wire to achieve today's high

Gray, Jeffrey J.

17

Development of a prototype Micro-Wire-EDM machine  

Microsoft Academic Search

With the demands on the minimization of surface roughness, decrease of the producible geometric dimensions and improvement of the machining accuracy, Micro-Wire-EDM with a wire diameter of 80?m and below has been a key technology for micro-machining. The purpose of this paper is to develop three key techniques for a prototype CNC micro-wire EDM machine. These techniques involve the development

Mu-Tian Yan; Chen-Wei Huang; Chi-Cheng Fang; Chia-Xuan Chang

2004-01-01

18

A study on the quality of micro-hole of Ti-6Al-4V by EDM process with on-machine measurement techniques  

NASA Astrophysics Data System (ADS)

A new on-machine measurement technique is proposed to observe the quality of micro-hole in micro Electrical Discharge Machining (EDM) progress. Images of micro-hole are captured by means of a simple configuration use a light-emitting diode (LED) illuminator, optical fiber, and a camera charge-coupled device (CCD).The device does not make contact with workpiece and acquire the image from the contour of the finished micro-hole. Because of using the optical fiber to transmit the real-time image, the device can woke in the narrow and small place. Based on the detected feature points, the geometrical features of the finished micro-hole such as its aperture can be obtained in real time. Meanwhile, the measuring result shows the micro-hole is whether or not qualified and can optimize the process parameters.

Li, Jun; Liu, Xiaoyu; Wei, Xingping; Zhao, Shiping

2013-10-01

19

A fatigue study of electrical discharge machine (EDM) strain-gage balance materials  

NASA Technical Reports Server (NTRS)

A fatigue study was undertaken to determine how much electrical-discharge-machine (EDM) processing affected the fatigue life of balance materials: EDM and regular milling-machine (MM) samples were compared. Simulation of a typical balance stress configuration was devised for the fatigue testing in order to obtain results more closely related to balance situations. The fatigue testing of the EDM and MM specimens has indicated that the EDM technique does indeed reduce the fatigue life of 15-5PH steel, the first balance material tested. This conclusion was based on comparisons of the specimen fatigue lives with theoretical and manufacturer's data. Hence the EDM surface effects are detrimental to the fatigue life of this balance material.

Rhew, Ray D.

1989-01-01

20

Processing of advanced ceramics using the wire-cut EDM process  

Microsoft Academic Search

This paper presents the processing of two advanced ceramics using Wire-Cut Electrical Discharge Machining (EDM) which is evolving as one of the promising method for the processing advanced ceramics. Two types of advanced ceramics, Sialon and Al2O3TiC, were machined successfully by the Wire-Cut EDM process. The machining performance in terms of material removal rate and surface finish were compared under

Y. K. Lok; T. C. Lee

1997-01-01

21

Micro-spherical probes machining by EDM  

Microsoft Academic Search

This paper describes a new hybrid micro-machining method, which combines wire electro discharge grinding technology with one pulse electro discharge, to fabricate micro-spherical probes and micro-spherical cavities. The results show that a burnished micro-spherical probe with about 40 m diameter could be formed instantaneously with the hybrid machining process, which is not available in the conventional micro-machining method. The deviation

Dong-Yea Sheu

2005-01-01

22

Data mining applied to wire-EDM process  

Microsoft Academic Search

Wire-EDM is a highly complex process, which is characterized by non-linear behavior. Due to a large number of input parameters, a data mining approach based on machine learning is followed in this paper to model this process. The model was trained on experimental data collected from carefully conducted experiments. The model was also tested on additional data. It is found

Shajan Kuriakose; Kamal Mohan; M. S Shunmugam

2003-01-01

23

Micro-spherical probes machining by EDM  

NASA Astrophysics Data System (ADS)

This paper describes a new hybrid micro-machining method, which combines wire electro discharge grinding technology with one pulse electro discharge, to fabricate micro-spherical probes and micro-spherical cavities. The results show that a burnished micro-spherical probe with about 40 m diameter could be formed instantaneously with the hybrid machining process, which is not available in the conventional micro-machining method. The deviation in diameter and roundness tolerances of micro-spherical probes is about 1 m and 3 m, respectively. Compared with conventional electro discharge machining, the surface roughness of the spherical probe is much smaller than a discharge crater. It will be possible to achieve more accurate three-dimensional measurements with the micro-spherical probe attached to the coordinate measuring machine in the future.

Sheu, Dong-Yea

2005-01-01

24

Performance testing of wire electric discharge machines (EDMs)  

SciTech Connect

This paper describes acceptance test requirements and techniques that were defined and specified by Lawrence Livermore National Laboratory (LLNL) to assure that they would ultimately receive a precision Wire Electric Discharge Machine (EDM) to meet their requirements. Unique methods of evaluating the performance of Wire EDMs are described. The results show that these EDMs can produce parts to precise overall form tolerances. Described are test methods that provide a means of separating the performance variables of EDM machines and an overview of how these tests can help predict the production of precision parts. Part histories are given to show attainable results. Basic parametric tests are: straightness, squareness, positioning accuracy, repeatability and backlash, 360/sup 0/ disc, and 360/sup 0/ magnetic ball bar (unique). The part cut performance tests described are: square, disc, and narrow slot.

Humpal, H.

1984-05-15

25

Development of an Eco-Friendly Electrical Discharge Machine (E-EDM) Using TRIZ Approach  

NASA Astrophysics Data System (ADS)

Electrical Discharge Machine (EDM) is one of the non-traditional machining processes. EDM process is based on thermoelectric energy between the work and an electrode. A pulse discharge occurs in a small gap between the work piece and the electrode and removes the unwanted material from the parent metal through melting and vaporization. The electrode and the work piece must have an electrical conductivity in order to generate the spark. Dielectric fluid acts as a spark conductor, concentrating the energy to a very narrow region. There are various types of products can be produced and finished using EDM such as Moulds, Dies, Parts of Aerodynamics, Automotives and Surgical components. This research work reveals how an Eco friendly EDM (E-EDM) can be modeled to replace die electric fluid and introducing ozonised oxygen in to EDM to eliminate harmful effects generated while machining by using dielectric, to make pollution free machining environment through a new design of EEDM using TRIZ (a Russian acronym for Theory of Inventive Problem Solving) approach, since Eco friendly design is the need of the hour.

Sreebalaji, V. S.; Saravanan, R.

26

Optimization of machining parameters of Wire-EDM based on Grey relational and statistical analyses  

Microsoft Academic Search

Grey relational analyses are applied to determine the optimal selection of machining parameters for the Wire Electrical Discharge Machining (Wire-EDM) process. The Grey theory can provide a solution for a system in which the model is unsure or the information is incomplete. Besides, it provides an efficient solution to the uncertainty, multi-input and discrete data problem. Based on Taguchi quality

J. T. Huang; Y. S. Liao

2003-01-01

27

Monitoring and control of the micro wire-EDM process  

Microsoft Academic Search

A new pulse discriminating and control system has been developed for process monitoring and control in micro wire-EDM. The pulse discriminating and control system identifies four major gap states classified as open circuit, normal spark, arc discharge and short circuit based on the characteristics of gap voltage waveform. The effect of pulse interval, machining feedrate and workpiece thickness on the

Mu-Tian Yan; Hsing-Tsung Chien

2007-01-01

28

Study of micro-electro discharge machining (micro-EDM) with on-machine measurement-assisted techniques  

Microsoft Academic Search

In this study on-machine measurement-assisted techniques are utilized in combination with micro-EDM to successfully machine intricate micro-parts. Two measurement approaches, automatic optical inspection (AOI) and critical contact measurement (CCM), are used on a previously built machine tool. AOI acquires the image from the contour of the machined workpiece and further processes the image to determine the finish allowance. CCM measures

Shun-Tong Chen; Hong-Ye Yang

2011-01-01

29

Study of micro-electro discharge machining (micro-EDM) with on-machine measurement-assisted techniques  

NASA Astrophysics Data System (ADS)

In this study on-machine measurement-assisted techniques are utilized in combination with micro-EDM to successfully machine intricate micro-parts. Two measurement approaches, automatic optical inspection (AOI) and critical contact measurement (CCM), are used on a previously built machine tool. AOI acquires the image from the contour of the machined workpiece and further processes the image to determine the finish allowance. CCM measures on-line the consumption of the microelectrode to create an accurate compensation rate. These two non-contact measurement techniques facilitate on-machine error detection and re-machining during micro-EDM. Significant work efficiency and preservation of machining accuracy are gained by having the workpiece and tool remain in place throughout machining procedures. A micro-probe with a diameter of 30 m and a micro 3D engraving mold on a small tungsten steel ball are perfectly fabricated and verified, respectively.

Chen, Shun-Tong; Yang, Hong-Ye

2011-06-01

30

Probability of precision micro-machining of insulating Si 3N 4 ceramics by EDM  

Microsoft Academic Search

Electrical discharge machining (EDM) is used as a precision machining method for the electrically conductive hard materials with a soft electrode material. But recently we succeeded to machine on insulating material by EDM. The technology is named as an assisting electrode method. The EDMed surface is covered with the electrical conductive layer during discharge. The layer holds the electrical conductivity

Apiwat Muttamara; Yasushi Fukuzawa; Naotake Mohri; Takayuki Tani

2003-01-01

31

Micro-hole machining using micro-EDM combined with electropolishing  

NASA Astrophysics Data System (ADS)

This paper presents a novel process of using micro-electro-discharge- machining (micro-EDM) combined with electropolishing to improve the surface roughness of micro-holes. During the machining process, a tool is fabricated by wire electro-discharge grinding (WEDG) directly by using micro-EDM for machining the micro-hole and by electropolishing to finish the hole wall. In this work, various micro-holes are machined on the high nickel alloy. By the electropolishing method, high surface quality of the hole wall is obtained by applying a suitable electrolytic voltage and an appropriate concentration of electrolyte in about 5 min of machining time. The taper and burrs of the inlet of holes are reduced, even for difficult- to-machine special-shaped micro-holes. The surface roughness reduced from 2.11 m Rmax before grinding to 0.69 m Rmax after electropolishing.

Hung, Jung-Chou; Yan, Biing-Hwa; Liu, Hung-Sung; Chow, Han-Ming

2006-08-01

32

Surface Integrity of C-40 Steel Processed with WC-Cu Powder Metallurgy Green Compact Tools in EDM  

Microsoft Academic Search

Electric discharge machining (EDM) is an electrothermal process where recast layer on the machined surface and heat-affected (HAZ) zone just below the machined surface are common phenomena. Thus, the assessment of surface integrity in EDM is a very important task. In this study, an attempt was made to modify the surface integrity of C-40 steel in EDM. WC-Cu powder metallurgy

P. K. Patowari; U. K. Mishra; P. Saha; P. K. Mishra

2011-01-01

33

Comparison on linear synchronous motors and conventional rotary motors driven Wire-EDM processes  

Microsoft Academic Search

Motion control of electrical discharge machining (EDM) processes is getting improved in recent years on both drive types and their control performance. This paper aims at comparison of the Wire-EDM's performance between driven by linear synchronous motors (LSM) and that by conventional rotary motors associated with ball-screw. Mathematical models of both drive types are derived and their parameters are identified

Albert W.-J. Hsue; M.-T. Yan; S.-H. Ke

2007-01-01

34

The Machining of Freeform Micro Moulds by Micro EDM; Work in Progress  

Microsoft Academic Search

Micro EDM has proved to be a versatile micro machining technology to produce complex threedimensional structures. An additional WEDG (Wire Electro Discharge Grinding) unit allows shaping of the tool electrode on the EDM-machine itself increasing the machining flexibility and machining performances. Micro moulds, with basic shapes, are machined to check both their mouldability and demouldability. Finally a micro mould is

W. Meeusen; D. Reynaerts; J. Peirs; H. Van Brussel; V. Dierickx; W. Driesen

35

Multiobjective optimization of the dry electric discharge machining process  

E-print Network

Multiobjective optimization of the dry electric discharge machining process Sourabh K. Saha*, S January 15, 2009 Abstract Dry Electric Discharge Machining (EDM) is an environmentfriendly modification: Electric Discharge Machining (EDM), Dry EDM, Design of experiments, Multiobjective optimization, NSGA II

Paris-Sud XI, Universit de

36

Microstructing of silicon by electro-discharge machining (EDM) part II: applications  

Microsoft Academic Search

Micro electro-discharge machining (EDM) is introduced as a new technique to produce microstructures. The main advantages of micro-EDM are its low installation cost, high accuracy and large design freedom. Micro-EDM can indeed easily machine complex three-dimensional shapes that prove difficult for etching techniques. The primary applications of micro-EDM are in rapid prototyping and products with small batch sizes. However, the

Paul-Henri's Heeren; Dominiek Reynaerts; Hendrik Van Brussel; Cynthia Beuret; Olle Larsson; Axel Bertholds

1997-01-01

37

Vertical EDM (electric discharge machining) using modular programming  

SciTech Connect

The usual function of computer numerically controlled (CNC) machining programs is to specify a sequence of machining operations. When CNC is applied to electric discharge machining (EDM), the possibilities and needs are much greater. This paper describes a modular system of programming in which various functions are carried out by subroutines contained in the controller memory. The subroutines are made more versatile by using variables. Such functions as orbiting, cavity inspection, electrode wear measurement and compensation, and multiple cavities are possible. 3 refs., 9 figs.

Fuller, J.E.

1989-01-01

38

Multi-spherical probe machining by EDM  

Microsoft Academic Search

This paper describes a new hybrid technique combining wire electro-discharge grinding (WEDG) technology with one-pulse electro-discharge (OPED), to fabricate multi-micro-spherical probes. The results show that a burnished micro-spherical probe with diameter of about 40?m could be formed instantaneously, which is not available with conventional machining methods. The unevenness of the radius is about 3?m with repeatedly machining at the same

Dong-Yea Sheu

2004-01-01

39

A simplified post process for wire cut EDM  

Microsoft Academic Search

The paper deals with a technical realization to improve the Wire EDM accuracy while cutting at full speed on virtually any contour. The system which is readily available on commercial wire EDM machines is based on the on-line monitoring and control of the wire position by means of an optical sensor. The deviation of the wire position relative to the

Ivano Beltrami; Axel Bertholds; Dirk Dauw

1996-01-01

40

Taguchi Method Implementation in Taper Motion Wire EDM Process Optimization  

NASA Astrophysics Data System (ADS)

Wire electrical discharge machining (Wire EDM) is a non-conventional metal removal process as well as one of the best manufacturing processes suitable for producing jigs, fixtures, and dies. Among others, the machine is able to cut a workpiece having oblique and taper form. The objective of this paper is to optimize the input parameters of Wire EDM machine, such as no load voltage, capacitor, on-time, off-time, and servo voltage, for machining medium carbon steel ASSAB 760. The Taguchi design of experiments, the signal-to-noise ratio, and analysis of variance are employed to analyze the effects of the input parameters by adopting L18 Taguchi orthogonal array (OA) to conduct experiments using brass wire electrode of 0.2 mm in diameter. In order to achieve the maximum material removal rate (MRR) or the minimum surface roughness (SR), six controllable factors, i.e., the parameters of each at three levels are applied for determining the optimal combination of factors and levels. The results reveal that the MRR and the SR are greatly influenced by the on-time and the taper angle, respectively. Experimental results affirm the effectiveness of the method, and also prove that the Taguchi method is suitable to solving the stated problem within minimum number of experiments as compared to that of a full factorial design.

Martowibowo, S. Y.; Wahyudi, A.

2012-10-01

41

Process characterization of Electrical Discharge Machining of highly doped silicon  

E-print Network

Electrical Discharge Machining (EDM) is an advanced machining process that removes material via thermal erosion through a plasma arc. The machining process is accomplished through the application of high frequency current ...

Crawford, Gregory Allan

2012-01-01

42

A machine vision system for micro-EDM based on linux  

NASA Astrophysics Data System (ADS)

Due to the high precision and good surface quality that it can give, Electrical Discharge Machining (EDM) is potentially an important process for the fabrication of micro-tools and micro-components. However, a number of issues remain unsolved before micro-EDM becomes a reliable process with repeatable results. To deal with the difficulties in micro electrodes on-line fabrication and tool wear compensation, a micro-EDM machine vision system is developed with a Charge Coupled Device (CCD) camera, with an optical resolution of 1.61?m and an overall magnification of 113~729. Based on the Linux operating system, an image capturing program is developed with the V4L2 API, and an image processing program is exploited by using OpenCV. The contour of micro electrodes can be extracted by means of the Canny edge detector. Through the system calibration, the micro electrodes diameter can be measured on-line. Experiments have been carried out to prove its performance, and the reasons of measurement error are also analyzed.

Guo, Rui; Zhao, Wansheng; Li, Gang; Li, Zhiyong; Zhang, Yong

2006-11-01

43

Using a helical micro-tool in micro-EDM combined with ultrasonic vibration for micro-hole machining  

NASA Astrophysics Data System (ADS)

This paper presents a novel process using micro-electro-discharge- machining (micro-EDM) combined with ultrasonic vibration by a helical micro-tool electrode to drill and finish micro-holes. During the machining processes, a micro-tool is directly fabricated by wire electro-discharge grinding (WEDG) using micro-EDM combined with various methods for machining the micro-hole and by ultrasonic vibration to finish the hole wall. In this work, circular micro-holes are machined in a high nickel alloy by cylindrical and helical electrodes. Using a helical micro-tool electrode for micro-EDM combined with ultrasonic vibration (HE-MEDM-UV) can substantially reduce the EDM gap, taper and machining time for deep micro-hole drilling. In addition, using a helical micro-tool with micro ultrasonic vibration finishing (HE-MUVF), good surface quality and less taper of the hole wall can be obtained by applying a suitable electrode step variation, rotational speed and ultrasonic amplitude with a machining time of approximately 25 min. According to scanning electron microscopy (SEM) micrographs and atomic force microscopy (AFM) measurement, HE-MUVF can indeed improve the surface roughness from 1.345 m Rmax before finishing to 0.58 m Rmax after HE-MUVF. This result demonstrates that using HE-MEDM-UV combined with MUVF can yield micro-holes of precise shape and smooth surface.

Hung, Jung-Chou; Lin, Jui-Kuan; Yan, Biing-Hwa; Liu, Hung-Sung; Ho, Ping-Hsing

2006-12-01

44

Fabrication Of Micro-Nozzles Via {mu}-EDM Process  

SciTech Connect

Since traditional handling mechanisms have an unpredictable behavior at micro scale, micro-assembly is a bottleneck in the development of hybrid micro-systems, and the development of new approaches is strongly demanded. In this paper, a recent study of the fabrication of a ceramics vacuum micro-gripper to handle parts in the range of hundreds of microns (300-1000) is presented. Among the possible micro manufacturing processes, micro-EDM has been selected as proving to be a very competitive fabrication technology for the manufacturing of ultra miniature components and micro sized features. The influence of the process parameters on the machining performance of interest is firstly investigated; then, the experimental results on machining the micro gripper are presented, finally concluding remarks are given.

Modica, F.; Trotta, G. [ITIA-CNR, Institute of Industrial Technology and Automation, National Research Council, Strada Crocefisso 2/B, 70126 Bari (Italy); Ferraris, E.; Reynaerts, D. [KatholiekeUniversiteit Leuven, PMA, Celestijnenlaan 300B -B-3001, Heverlee (Belgium); Fassi, I. [ITIA-CNR, Institute of Industrial Technology and Automation, National Research Council, via Bassini 15, 20131 Milano (Italy)

2011-01-17

45

Fabrication Of Micro-Nozzles Via ?-EDM Process  

NASA Astrophysics Data System (ADS)

Since traditional handling mechanisms have an unpredictable behavior at micro scale, micro-assembly is a bottleneck in the development of hybrid micro-systems, and the development of new approaches is strongly demanded. In this paper, a recent study of the fabrication of a ceramics vacuum micro-gripper to handle parts in the range of hundreds of microns (300-1000) is presented. Among the possible micro manufacturing processes, micro-EDM has been selected as proving to be a very competitive fabrication technology for the manufacturing of ultra miniature components and micro sized features. The influence of the process parameters on the machining performance of interest is firstly investigated; then, the experimental results on machining the micro gripper are presented, finally concluding remarks are given.

Modica, F.; Ferraris, E.; Trotta, G.; Fassi, I.; Reynaerts, D.

2011-01-01

46

Monitoring of the electrical discharge machining process by abductive networks  

Microsoft Academic Search

The paper describes the use of abductive networks to monitor the electrical discharge machining (EDM) process. The voltage and current across the gap between the tool and workpiece are fed into the developed networks for the recognition of various pulse types in EDM in a winner-take-all fashion. Experimental results have shown that EDM pulses can be clearly classified even with

H. S. Liu; Y. S. Tarng

1997-01-01

47

Temperature measurements and numerical analysis of the heat transfer in samples submitted to electron discharge machining (EDM)  

Microsoft Academic Search

Summary form only given. Matter removal in the electron discharge machining (EDM) is essentially due to a thermal mechanism. The control of the thermal process (i.e. the time dependent energy flow given by the discharge and the local temperature evolution) is therefore of crucial importance for efficiency and surface quality improvement. We report the first results of our research aimed

B. Revaz; R. Flukiger; J. Carron; M. Rappaz

2004-01-01

48

Study on modeling of wire EDM process  

Microsoft Academic Search

Wire electrical discharge machining (WEDM) technology has been used widely in production, aerospace\\/aircraft, medical and virtually all areas of conductive material machining. Its complexity and stochastic nature have stimulated numerous attempts to model it accurately. This paper presents an attempt at modeling the process through Response Surface Methodology and Artificial Neural Networks. A response surface model based on a central

T. A Spedding; Z. Q Wang

1997-01-01

49

Electrode verification and management system for automation of EDM process in mould industry  

Microsoft Academic Search

In order to remain highly competitive, mould makers are compelled to shorten lead-time to produce mistake free complex mould for high value quick-turnaround products. One of the critical processes in mould making is the electro-discharge machining (EDM) process, which uses a large variety of precisely machined electrodes for making thin walls and sharp pockets. Potential sources of errors, particularly from

Hao Zeng; Beng Siong Lim; Geok Hong Phua; Zhongqiang Ding; Leck Leng Aw; Toh Khoong Tan; Xiang Li; Kiah Mok Goh; Pin Tat Hee; Yan Chuan Goh; Kok Kee Yuen

2005-01-01

50

Improvement of machining accuracy by fuzzy logic at corner parts for wire-EDM  

Microsoft Academic Search

Wire electrical discharge machining (wire-EDM) has always occupied an important position in some production fields, due to its capability of machining hard materials and intricate shapes. However, the machining accuracy, especially at corner parts, may be destroyed because of some phenomena such as wire deflection and vibration, etc. The purpose of this paper is to develop a control strategy based

Chin-teng Lin; I-fang Chung; Shih-yu Huang

2001-01-01

51

Surface modification of AlZnMg aluminum alloy using the combined process of EDM with USM  

Microsoft Academic Search

This paper presents a novel technique to improve the machined surface of AlZnMg aluminum alloy by a combined machining process of electrical discharge machining (EDM) with ultrasonic machining (USM). In these experiments, SiC particles were added into the dielectric fluid to produce a particle-reinforced mechanism and solid solution strengthened structure to form a modified layer on the machined surface in

Yan Cherng Lin; Biing Hwa Yan; Fuang Yuan Huang

2001-01-01

52

Surface modifications of AlZnMg alloy using combined EDM with ultrasonic machining and addition of TiC particles into the dielectric  

Microsoft Academic Search

This study proposes a novel combined process that integrates electrical discharge machining (EDM) and ultrasonic machining (USM) to investigate the machining performance and surface modification on AlZnMg alloy. In the experiment, TiC particles were added into the dielectric to explore the influence of the combined process on the material removal rate (MRR), the relative electrode wear ratio (REWR), the surface

Yuan-Feng Chen; Yan-Cherng Lin

2009-01-01

53

Development of the Cylindrical Wire Electrical Discharge Machining Process.  

SciTech Connect

Results of applying the wire Electrical Discharge Machining (EDM) process to generate precise cylindrical forms on hard, difficult-to-machine materials are presented. A precise, flexible, and corrosion-resistant underwater rotary spindle was designed and added to a conventional two-axis wire EDM machine to enable the generation of free-form cylindrical geometries. A detailed spindle error analysis identifies the major source of error at different frequency. The mathematical model for the material removal of cylindrical wire EDM process is derived. Experiments were conducted to explore the maximum material removal rate for cylindrical and 2D wire EDM of carbide and brass work-materials. Compared to the 2D wire EDM, higher maximum material removal rates may be achieved in the cylindrical wire EDM. This study also investigates the surface integrity and roundness of parts created by the cylindrical wire EDM process. For carbide parts, an arithmetic average surface roughness and roundness as low as 0.68 and 1.7 {micro}m, respectively, can be achieved. Surfaces of the cylindrical EDM parts were examined using Scanning Electron Microscopy (SEM) to identify the craters, sub-surface recast layers and heat-affected zones under various process parameters. This study has demonstrated that the cylindrical wire EDM process parameters can be adjusted to achieve either high material removal rate or good surface integrity.

McSpadden, SB

2002-01-22

54

Development of ultra-precision machining system with unique wire EDM tool fabrication system for micro\\/nano-machining  

Microsoft Academic Search

Aiming at quality machining of very hard materials with nanometer level surface quality and 0.1?m dimensional accuracy, an ultra-precision machining system has been developed. The machine has feed axes accompanied by the counter motion mechanism driven at the center of gravity to eliminate the vibration caused by high acceleration\\/deceleration. A custom tool fabrication system consists of a 6-axis wire EDM

X. Cheng; K. Nakamoto; M. Sugai; S. Matsumoto; Z. G. Wang; K. Yamazaki

2008-01-01

55

EDM machinability of SiCw/Al composites  

NASA Technical Reports Server (NTRS)

Machinability of high temperature composites was investigated. Target materials, 15 and 25 vol pct SiC whisker-2124 aluminum composites, were machined by electrodischarge sinker machining and diamond saw. The machined surfaces of these metal matrix composites were examined by SEM and profilometry to determine the surface finish. Microhardness measurements were also performed on the as-machined composites.

Ramulu, M.; Taya, M.

1989-01-01

56

Traveling wire electrode increases productivity of Electrical Discharge Machining /EDM/ equipment  

NASA Technical Reports Server (NTRS)

Traveling wire electrode on electrical discharge machining /EDM/ equipment reduces the time requirements for precision cutting. This device enables cutting with a minimum of lost material and without inducing stress beyond that inherent in the material. The use of wire increases accuracy and enables tighter tolerances to be maintained.

Kotora, J., Jr.; Smith, S. V.

1967-01-01

57

Finishing effect of abrasive flow machining on micro slit fabricated by wire-EDM  

Microsoft Academic Search

This experimental research use the method of abrasive flow machining (AFM) to evaluate the characteristics of various levels\\u000a of roughness and finishing of the complex shaped micro slits fabricated by wire electrical discharge machining (Wire-EDM).\\u000a An investigative methodology based on the Taguchi experimental method for the micro slits of biomedicine was developed to\\u000a determine the parameters of AFM, including abrasive

Hsinn-Jyh Tzeng; Biing-Hwa Yan; Rong-Tzong Hsu; Han-Ming Chow

2007-01-01

58

Study on an evaluation method of micro CMM spherical stylus tips by -EDM on-machine measurement  

Microsoft Academic Search

This paper describes an on-machine measurement function of a micro electro-discharge machine (-EDM) to evaluate the quality of micro ball-ended stylus tips fabricated by a combination of wire-electro-discharge grinding (WEDG) and one-pulse-electro-discharge (OPED) technology. A low-voltage contacting trigger function without any capacitor between a stationary wire and the spindle of a -EDM was used to measure the outer profile and

Dong-Yea Sheu

2010-01-01

59

Simultaneous Processing Method for Micro-Rods and Holes Using EDM  

NASA Astrophysics Data System (ADS)

This paper describes a new method for micro-EDM drilling which utilizes the wear of rod electrodes. With this method, a pair of micro rod and micro hole can be machined in a single process, while with conventional methods, the micro rod electrode needs to be formed before machining the micro hole. Processing conditions were optimized for the new method to obtain higher aspect ratio for the micro rods. Results of experiments also showed the following: 1) This method can be applied to AISI1045, AISI304 and Kovar and any electrode diameter size. 2) From the second process, if machining many holes using the same electrode, the electrode shape can be regenerated with excellent repeatability and holes processed efficiently. 3) The influence of carbon adhering to the tip region of the rod electrode is large, which is why the rod electrode becomes needle sharp.

Yamazaki, Minoru; Mori, Noritosi; Suzuki, Takemi; Kunieda, Masanori

60

Environmental constituents of Electrical Discharge Machining  

E-print Network

Electrical Discharge Machining (EDM) is a non-traditional process that uses no mechanical forces to machine metals. It is extremely useful in machining hard materials. With the advantages EDM has to offer and its presence ...

Cho, Margaret H. (Margaret Hyunjoo), 1982-

2004-01-01

61

Local temperature response to pulsed discharges in electronic discharge machining (EDM) environment  

Microsoft Academic Search

We report on local temperature measurements performed during single discharges in electronic discharge machining (EDM) environment. Measurements have been performed with two different setups. One being a thermal device consisting of 14 thin film Au-Pd thermocouples. This device with 4-?m2 large junctions was patterned using standard photolithography. The distance between the junctions (i.e., the local resolution of the device) is

Bernard Revaz; Jonathan Emery; Grgoire Witz; Ren Flkiger; Roberto Perez; Jonathan Carron; Michel Rappaz

2005-01-01

62

High accuracy motion control of linear motor drive wire-EDM machines  

Microsoft Academic Search

This paper is aim to develop and investigate a permanent magnet linear-motor-driven table system for a wire-EDM machine. Dynamic model and system identification of the linear motor system have been derived and analyzed. The linear motor drive system has nonlinear and time-varying behaviors because of the effect of irregular friction of the sliding surface and cogging force. Therefore, a conventional

Mu-Tian Yan; Tun-Hua Cheng

2005-01-01

63

High accuracy motion control of linear motor drive wire-EDM machines  

Microsoft Academic Search

This paper aims to develop and investigate a permanent magnet linear-motor-driven table system for a wire-EDM machine. A dynamic\\u000a model and system identification of `the linear motor system have been derived and analyzed. The linear motor drive system\\u000a has nonlinear and time-varying behaviors because of the effect of irregular friction of the sliding surface and cogging force.\\u000a Therefore, a conventional

Mu-Tian Yan; Tun-Hua Cheng

2009-01-01

64

A new method of optimising material removal rate using EDM with coppertungsten electrodes  

Microsoft Academic Search

Electrical discharge machining (EDM) is widely used in the production of dies. This paper describes an investigation into the optimisation of the process which uses the effect of carbon which has migrated from the dielectric to tungstencopper electrodes. This work has led to the development of a two-stage EDM machining process where different EDM settings are used for the two

Jose Marafona; Catherine Wykes

2000-01-01

65

Electrical Discharge Machining.  

ERIC Educational Resources Information Center

The manual is for use by students learning electrical discharge machining (EDM). It consists of eight units divided into several lessons, each designed to meet one of the stated objectives for the unit. The units deal with: introduction to and advantages of EDM, the EDM process, basic components of EDM, reaction between forming tool and workpiece,

Montgomery, C. M.

66

Tool fabrication system for micro/nano millingfunction analysis and design of a six-axis Wire EDM machine  

E-print Network

with simple geometries using standard WEDM machines. Theresimple geometry using a standard three-axis Wire EDM machine [machine tool used for the fabrication of micro/nano milling cutters needs to have such functions for the fabrication of simple

Cheng, X.; Wang, Z. G.; Kobayashi, S.; Nakamoto, K.; Yamazaki, K.

2010-01-01

67

Investigation of the effect of process parameters on the formation and characteristics of recast layer in wire-EDM of Inconel 718  

Microsoft Academic Search

Inconel 718 is a high nickel content superalloy possessing high strength at elevated temperatures and resistance to oxidation and corrosion. The non-traditional manufacturing process of wire-electrical discharge machining (EDM) possesses many advantages over traditional machining during the manufacture of Inconel 718 parts. However, certain detrimental effects are also present and are due in large part to the formation of the

Thomas R. Newton; Shreyes N. Melkote; Thomas R. Watkins; Rosa M. Trejo; Laura Reister

2009-01-01

68

An investigation on effects of wire-EDM machining parameters on surface roughness of newly developed DC53 die steel  

Microsoft Academic Search

DC53 is a newly developed cold die steel from Daido Steel, Japan. It is an improvement over the familiar cold die steel SKD11. Because DC53 is a new die steel, only little information is available in literature for its machining characteristics. This paper investigated the effects of machining parameters on surface roughness of wire EDMed DC53 die steel. The investigated

K. Kanlayasiri; S. Boonmung

2007-01-01

69

Tool fabrication system for micro\\/nano millingfunction analysis and design of a six-axis Wire EDM machine  

Microsoft Academic Search

The dies or molds used for the fabrication of micro products usually are made of ultra-hard materials such as tungsten carbide\\u000a or silicon carbide and have sophisticated three-dimensional geometries. Such kind of dies or molds can only be fabricated\\u000a by milling operations instead of grinding processes with ultra-hard milling tools made of PCD or CBN. Electrical discharge\\u000a machining (EDM) is

X. Cheng; Z. G. Wang; S. Kobayashi; K. Nakamoto; K. Yamazaki

2010-01-01

70

Characterization of nanoparticles from abrasive waterjet machining and electrical discharge machining processes.  

PubMed

Abrasive Waterjet Machining (AWM) and Electrical Discharge Machining (EDM) processes are found to produce nanoparticles during operation. Impacts of engineered nanoparticles released to the environment and biological system have caused much concern. Similarly, the nanoparticles unintentionally produced by the AWM and EDM can lead to comparable effects. By application of the Nanoparticle Tracking Analysis (NTA) technique, the size distribution and concentration of nanoparticles in the water used in AWM and EDM were measured. The particles generally have a peak size of 100-200 nm. The filtration systems of the AWM and EDM processes were found to remove 70% and 90% the nanoparticles present, respectively. However, the particle concentration of the filtered water from the AWM was still four times higher than that found in regular tap water. These nanoparticles are mostly agglomerated, according to the microscopy analysis. Using the electron dispersive spectroscopy (EDS) technique, the particles are confirmed to come from the debris of the materials cut with the equipment. Since AWM and EDM are widely used, the handling and disposal of used filters collected with nanoparticles, release of nanoparticles to the sewer, and potential use of higher performance filters for these processes will deserve further consideration. PMID:24144041

Ling, Tsz Yan; Pui, David Y H

2013-11-19

71

The use of the orthogonal array with grey relational analysis to optimize the electrical discharge machining process with multiple performance characteristics  

Microsoft Academic Search

In this paper a new approach for the optimization of the electrical discharge machining (EDM) process with multiple performance characteristics based on the orthogonal array with the grey relational analysis has been studied. A grey relational grade obtained from the grey relational analysis is used to solve the EDM process with the multiple performance characteristics. Optimal machining parameters can then

J. L Lin; C. L Lin

2002-01-01

72

Study of the effect of machining parameters on the machining characteristics in electrical discharge machining of tungsten carbide  

Microsoft Academic Search

Electrical discharge machining (EDM) is a process for shaping hard metals and forming deep and complex-shaped holes by arc erosion in all kinds of electro-conductive materials. The objective of this research is to study the influence of operating parameters of EDM of tungsten carbide on the machining characteristics. The effectiveness of the EDM process with tungsten carbide is evaluated in

S. H. Lee; X. P. Li

2001-01-01

73

Effects of finishing processes on the fatigue life improvements of electro-machined surfaces of tool steel  

Microsoft Academic Search

Machining the EN X160CrMoV12 tool steel by electro-discharge machining (EDM) process generates significant modifications of\\u000a microgeometrical, microstructural and mechanical properties of the upper layers of the machined components. In this paper,\\u000a the role of these modifications in controlling the stability, under cyclic loading, of the propagation of the crack networks\\u000a generated by EDM is discussed. High cycle fatigue tests (2??106

Farhat Ghanem; Nabil Ben Fredj; Habib Sidhom; Chedly Braham

2011-01-01

74

PARAMETRIC INFLUENCE AND OPTIMIZATION OF WIRE EDM OF HOT DIE STEEL  

Microsoft Academic Search

Wire-cut Electro Discharge Machining (WEDM) is a special form of conventional EDM process in which the electrode is a continuously moving conductive wire. The present study aims at determining parametric influence and optimum process parameters of Wire-EDM using Taguchi's technique and a Genetic algorithm. The variation of the performance parameters with machining parameters was mathematically modeled by Regression analysis method.

Nixon Kuruvila; Ravindra H. V

2011-01-01

75

Surface modification of AlZnMg alloy by combined electrical discharge machining with ball burnish machining  

Microsoft Academic Search

The study investigated the feasibility of modifying the surface of AlZnMg alloy by a combined process of electric discharge machining (EDM) with ball burnish machining (BBM). A novel process that integrates EDM and BBM is also developed to conduct experiments on an electric discharge machine. Machining parameters of the combined process, including machining polarity, peak current, power supply voltage, and

B. H. Yan; Y. C. Lin; F. Y. Huang

2002-01-01

76

Electrical discharge machining in dentistry.  

PubMed

A brief history of electrical discharge machining (EDM) is given and the process is discussed. A description of the application of EDM for fabricating precision attachment removable partial dentures, fixed-removable implant prostheses, and titanium-ceramic crowns is presented. The advantages and disadvantages of the EDM process for the dental profession are evaluated. Although expensive, the procedure has merit. PMID:1524631

Van Roekel, N B

1992-01-01

77

Modeling and compensation of cutting-forces generated during the EDM process for ultra high-precision robots  

E-print Network

Modeling and compensation of cutting-forces generated during the EDM process for ultra high kinematic). Figure 2 Kinematic chain of the robot. The micro-EDM process is used for cutting complex shapes, an electrode or a wire is mounted on the robot end- effector. A controlled electrical spark is used to erode

Floreano, Dario

78

Technological Advancement in Electrical Discharge Machining with Powder Metallurgy Processed Electrodes: A Review  

Microsoft Academic Search

Electrical discharge machining (EDM) is a well-established machining option for processing hard materials with complex geometrical shapes which are extremely difficult-to-machine by conventional machining processes. These hard materials find applications where lower surface cracks, wear resistance, corrosion resistance, etc. are desirable surface properties. In recent years, research has been carried out to determine the possibility of employing electrode as feed

Naveen Beri; Sachin Maheshwari; Chitra Sharma; Anil Kumar

2010-01-01

79

Development of a high precision tabletop versatile CNC wire-EDM for making intricate micro parts  

Microsoft Academic Search

The micro-electrical discharge machining (micro-EDM) process has been proved to be appropriate for making 3D micro parts that are difficult and even impossible to manufacture by other processes. In this paper a high precision tabletop CNC wire electrical discharge machine (wire EDM) designed specifically for machining complex shape micro parts or structures is developed. In the machine developed, a novel

Yunn-Shiuan Liao; Shun-Tong Chen; Chang-Sheng Lin

2005-01-01

80

Investigation of the effect of process parameters on the formation and characteristics of recast layer in wire-EDM of Inconel 718  

SciTech Connect

Inconel 718 is a high nickel content superalloy possessing high strength at elevated temperatures and resistance to oxidation and corrosion. The non-traditional manufacturing process of wire-electrical discharge machining (EDM) possesses many advantages over traditional machining during the manufacture of Inconel 718 parts. However, certain detrimental effects are also present and are due in large part to the formation of the recast layer. An experimental investigation was conducted to determine the main EDM parameters which contribute to recast layer formation in Inconel 718. It was found that average recast layer thickness increased primarily with energy per spark, peak discharge current, and current pulse duration. Over the range of parameters tested, the recast layer was observed to be between 5 and 9 {micro}m in average thickness, although highly variable in nature. The recast material was found to possess in-plane tensile residual stresses, as well as lower hardness and elastic modulus than the bulk material.

Newton, Thomas R [Georgia Institute of Technology; Melkote, Shreyes N [Georgia Institute of Technology; Watkins, Thomas R [ORNL; Trejo, Rosa M [ORNL; Riester, Laura [ORNL

2009-01-01

81

Study on an evaluation method of micro CMM spherical stylus tips by -EDM on-machine measurement  

NASA Astrophysics Data System (ADS)

This paper describes an on-machine measurement function of a micro electro-discharge machine (-EDM) to evaluate the quality of micro ball-ended stylus tips fabricated by a combination of wire-electro-discharge grinding (WEDG) and one-pulse-electro-discharge (OPED) technology. A low-voltage contacting trigger function without any capacitor between a stationary wire and the spindle of a -EDM was used to measure the outer profile and evaluate the forming quality. The measurement results show that the deviation of the largest radius between the micro ball-ended tip and stem is approximately 3 m. Moreover, OPED/WEDG is also easily able to produce high-quality micro spherical stylus tips with a standard deviation as small as 0.7 m through use of sharp-needle-shaped electrode tools. With further improvements in electro-discharge position, OPED and WEDG technology are promising and excellent approaches for manufacturing micro coordinate measurement machine (CMM) spherical stylus tips.

Sheu, Dong-Yea

2010-07-01

82

Effect of the Machining Processes on Low Cycle Fatigue Behavior of a Powder Metallurgy Disk  

NASA Technical Reports Server (NTRS)

A study has been performed to investigate the effect of various machining processes on fatigue life of configured low cycle fatigue specimens machined out of a NASA developed LSHR P/M nickel based disk alloy. Two types of configured specimen geometries were employed in the study. To evaluate a broach machining processes a double notch geometry was used with both notches machined using broach tooling. EDM machined notched specimens of the same configuration were tested for comparison purposes. Honing finishing process was evaluated by using a center hole specimen geometry. Comparison testing was again done using EDM machined specimens of the same geometry. The effect of these machining processes on the resulting surface roughness, residual stress distribution and microstructural damage were characterized and used in attempt to explain the low cycle fatigue results.

Telesman, J.; Kantzos, P.; Gabb, T. P.; Ghosn, L. J.

2010-01-01

83

A neutral-network approach for the on-line monitoring of the electrical discharge machining process  

Microsoft Academic Search

In this paper, a feed-forward neural network is used to on-line monitor electrical discharge machining (EDM) processes. The relationships between tool-workpiece gap signals and various pulse types are established, based on the neural network through the back-propagation learning algorithm. As a result, the developed neural network can be used to monitor varying machining conditions in EDM. Experimental results have shown

J. Y Kao; Y. S Tarng

1997-01-01

84

Fabrication of a micro-spherical tool in EDM combined with Ni-diamond co-deposition  

Microsoft Academic Search

This paper demonstrates a novel fabrication process using electro-discharge-machining (EDM) combined with co-deposited Ni-diamond composites to build a unique micro-spherical diamond tool. A micro tool is made by a hybrid process including wire electro-discharge grinding, EDM spherical forming, electrochemical machining and co-deposition. Tungsten carbide material is used as the tool substrate. The influence of EDM spherical forming and co-deposition parameters

Jung-Chou Hung; Shao-Chun Lien; Jui-Kuan Lin; Fuang-Yuan Huang; Biing-Hwa Yan

2008-01-01

85

M3EDM: MEMS-enabled micro-electro-discharge machining  

NASA Astrophysics Data System (ADS)

This paper reports a photolithography compatible micro-electro-discharge machining technique that is performed with microelectrode actuators driven by hydrodynamic force. The movable planar electrodes suspended by the anchors are microfabricated directly on the workpiece. The electrode structures with fixed fixed and cantilever configurations are defined by patterning 18 m thick copper foil laminated on the workpiece through an intermediate photoresist layer and released by sacrificial etching of the resist layer. All the patterning and sacrificial etching steps are performed using dry-film photoresists towards achieving high scalability of the machining technique to large-area applications. The parasitic capacitance of the electrode structure is used to form a resistance capacitance circuit for the generation of pulsed spark discharge between the electrode and the workpiece. The suspended electrodes are actuated towards the workpiece using the downflow of dielectric machining fluid, initiating and sustaining the machining process. Micromachining of stainless steel is experimentally demonstrated with a machining voltage of 90 V and continuous flow of the fluid at a velocity of 3.4 3.9 m s-1, providing a removal depth of 20 m with an average surface roughness of 520 nm. The experimental results of the electrode actuation are shown to agree well with the theoretical estimations.

Reddy Alla Chaitanya, Chakravarty; Takahata, Kenichi

2008-10-01

86

Vibration-assisted servo scanning 3D micro EDM  

Microsoft Academic Search

In scanning micro electrical discharge machining (EDM), the machining time for a 3D mould cavity is longer due to the smaller discharge area of a thin wire tool electrode. Moreover, a stable discharge area is hardly kept because of the scanning motion, resulting in a lower discharge ratio. To improve the machining process, a method of workpiece vibration-assisted servo scanning

Tong Hao; Wang Yang; Li Yong

2008-01-01

87

Influence of Process Parameters and Electrode Geometry on Feature Micro-Accuracy in Electro Discharge Machining of Tool Steel  

Microsoft Academic Search

Agile manufacturing capabilities require fast responses in workshops to cope with different demands in product geometrical features and qualities in fabricating moulds. Therefore, direct machining of complex mould features using simple shape machined electrodes with the electro-discharge machining (EDM) process, empowers the flexibility and the capacity of the enterprises and dramatically reduces lead times resulting in much more efficient production

N. Pellicer; J. Ciurana; T. Ozel

2009-01-01

88

Wire EDM for Refractory Materials  

NASA Technical Reports Server (NTRS)

In an attempt to reduce fabrication time and costs, Wire Electrical Discharge Machine (Wire EDM) method was investigated as tool for fabricating matched blade roots and disk slots. Eight high-strength nickel-base superalloys were used. Computer-controlled Wire EDM technique provided high quality surfaces with excellent dimensional tolerances. Wire EDM method offers potential for substantial reductions in fabrication costs for "hard to machine" alloys and electrically conductive materials in specific high-precision applications.

Zellars, G. R.; Harris, F. E.; Lowell, C. E.; Pollman, W. M.; Rys, V. J.; Wills, R. J.

1982-01-01

89

Study of added powder in kerosene for the micro-slit machining of titanium alloy using electro-discharge machining  

Microsoft Academic Search

This work presents a revised EDM process by quantitatively and qualitatively measuring the process using different dielectric fluids. The revised EDM process is developed by modifying the discharging circuit to minimize the discharging current and introducing a new driven mechanism with horizontal rotating electrode. By applying a thin copper diskette electrode, titanium alloy is machined using micro-slit EDM with various

Han-Ming Chow; Biing-Hwa Yan; Fuang-Yuan Huang; Jung-Cherng Hung

2000-01-01

90

Effects of wire-EDM machining variables on surface roughness of newly developed DC 53 die steel: Design of experiments and regression model  

Microsoft Academic Search

DC53 is a newly developed cold die steel from Daido Steel, Japan. It is an improvement over the familiar cold die steel SKD11. Because DC53 is a new die steel, only little information is available in literature for its machining characteristics. This paper presents an investigation of the effects of machining variables on the surface roughness of wire-EDMed DC53 die

K. Kanlayasiri; S. Boonmung

2007-01-01

91

Micro-CT evaluation of in vivo osteogenesis at implants processed by wire-type electric discharge machining.  

PubMed

Titanium surfaces processed by wire-type electric discharge machining (EDM) are microfabricated surfaces with an irregular morphology, and they exhibited excellent in vitro bone biocompatibility. In this study, the efficiency of in vivo osteogenesis on EDM surfaces was investigated by surgically placing screw-shaped EDM-processed and machined-surface implants into the femurs of four Japanese white rabbits. The volume and process of new bone formation were evaluated by an X-ray micro-CT scanner, coupled with histopathological observations at 1, 2, and 4 weeks post-implantation. Before surgical implantation, the surface topography and contact angle of each implant surface were examined. Bone formation increased over time on both implant surfaces, with both implant types yielding statistically equivalent bone volume at 4 weeks post-implementation. However, at 1 week post-implantation, amount of new bone at EDM-processed implant was markedly greater than that at machined-surface implant. Moreover, new bone appeared to initiate directly from the EDM surfaces, while new bone appeared to generate from pre-existing host bone to the machined surfaces. Thus, EDM seemed to be a promising method for surface modification of titanium implants to support enhanced osteogenesis. PMID:22673455

Yamaki, Koichi; Kataoka, Yu; Ohtsuka, Fukunaga; Miyazaki, Takashi

2012-01-01

92

High aspect ratio meso-scale parts enabled by wire micro-EDM  

Microsoft Academic Search

Micro-electro discharge machining (EDM) is a subtractive meso-scale machining process. The Agie Excellence 2F wire micro\\u000a EDM is capable of machining with a 25 micron diameter wire electrode and positioning the work piece to within 1.5 microns.\\u000a The over-burn gap can be controlled to within 3 microns to obtain a minimum feature radius of about 16 microns while achieving\\u000a submicron

G. L. Benavides; L. F. Bieg; M. P. Saavedra; E. A. Bryce

2002-01-01

93

Multi-objective optimization of wire-electro discharge machining process by Non-Dominated Sorting Genetic Algorithm  

Microsoft Academic Search

Wire-electro discharge machining (Wire-EDM or WEDM) is one of the important non-traditional machining processes, which is used for machining of difficult-to-machine materials and intricate profiles. Being a complex process, it is very difficult to determine optimal parameters for improving cutting performance. Cutting velocity and surface finish are most important output parameters, which decide the cutting performance. There is no single

Shajan Kuriakose; M. S. Shunmugam

2005-01-01

94

Fabrication of a miniature diamond grinding tool using a hybrid process of micro-EDM and co-deposition  

Microsoft Academic Search

A novel miniature diamond grinding tool usable for the precise micro-grinding of miniature parts is presented. A hybrid process that combines 'micro-EDM' with 'precision co-deposition' is proposed. The metal substrate is micro-EDMed to a 50 m diameter and micro diamonds with 0-2 m grains are 'electroformed' on the substrate surface, producing a miniature multilayered grinding tool. Nickel and diamond act

Shun-Tong Chen; Yun-Cheng Lai; Ching-Chang Liu

2008-01-01

95

Optimization of metal removal rate and surface roughness on wire EDM using taguchi method  

Microsoft Academic Search

This paper deals with finding five optimal control parameters input voltage, current, speed, pulse on\\/off time to maximize metal removal rate (MRR) and minimize surface roughness (SR) on wire edm (electrical discharge machining). Wire edm is an electro thermal production process in which a thin single strand metal wire in conjuction with de-ionised water (used to conduct electricity), allows the

S. R. Nithin Aravind; S. Sowmya; K. P. Yuvaraj

2012-01-01

96

Fuzzy logic modeling of wire-cut EDM process  

NASA Astrophysics Data System (ADS)

Intelligent control of any manufacturing process requires an appropriate modeling of the process. Wire-cut EMD, being a highly complex process with non-linear behavior, is modeled by fuzzy logic approach in this paper . The knowledge base for the fuzzy model has been developed using the experimental results. Membership functions are defined for each parameter and a total of 10 input and 2 output parameters are considered to build the model. The results of the fuzzy model are compared with experimental values and a statistical analysis is presented.

Shunmugam, M. S.; Kumar, S. S.; Kaul, I. K.

2000-10-01

97

Micro-EDM for silicon microstructure fabrication  

NASA Astrophysics Data System (ADS)

Currently, most silicon microstructures used in microstructures are produced by photolithographic methods. The reason for this is the well-developed etching technology, used in microelectronics, that has been transferred to the microsystem domain. But since the making of an arbitrary shape or angle on silicon mainly depends on the crystal orientation, some severe limits exist in the production of 3D structures. Electro-discharge machining (EDM) is basically a thermal process. During the EDM process material is removed by electric sparking. It is therefore completely different from etching. In this work, micro-EDM is introduce as a potential approach for solving the above mentioned drawbacks. First, this work presents several testing experiments with different process parameters to investigate the influence of the micro-EDM process on the silicon structure. Main emphasis is put on the surface roughness and on avoiding microcracks generated by the sparking process. It is found that microstructures with a sufficiently low surface roughness and with small microcracks can be produced. The remainder of the work concentrates on making small beam structures, which is a common structure in many microsensor designs. It is found that for a wafer thickness of 650 micrometers , the thinnest beam that can be produced is about 30 micrometers wide. This means that micro-EDM can offer an aspect ratio of 20 in combination with a god dimensional control.

Song, Xiaozhong; Reynaerts, Dominiek; Meeusen, Wim; Van Brussel, Hendrik

1999-03-01

98

Electro discharge machining of nickeltitanium shape memory alloys  

Microsoft Academic Search

Electro discharge machining (EDM) is a common fabrication process for miniaturized components in medical technology and micro engineering today. As EDM induces material changes in the near surface zone, the surface integrity becomes ever more important, the smaller the components are. In order to characterize the influence of EDM on the near surface zone, basic metallurgical investigations on pseudo-elastic NiTi

W Theisen; A Schuermann

2004-01-01

99

Unsteady processes in machines.  

PubMed

Couplings in machines and mechanisms always have play and friction. While under loading, stick-slip phenomena and impact events can take place. Such processes are modeled as multibody systems whose structure is time variant or unsteady. The time-variant number of degrees of freedom is due to stick-slip contacts. The coupling characteristics become unsteady, for instance there exist jumps in the loads, if impacts occur. For establishing a uniform theory for such phenomena we use a Lagrangian approach connecting the additional constraint equations and the equations of motion by Lagrange multipliers, which are proportional to the constraint forces. Stick-slip and impact events are evaluated by indicator functions leading to special numerical algorithms for the search of switching points. Contact problems are formulated as a complementarity problem which can be solved by efficient algorithms. The theory is applied to rattling in gears, impact drilling machines, turbine blade dampers, and a woodpecker toy. In some of these applications, chaos as a result of bifurcations is possible, which results from variations in the parameters. (c) 1994 American Institute of Physics. PMID:12780146

Pfeiffer, Friedrich

1994-12-01

100

Use of in-process EDM truing to generate complex contours on metal-bond, superabrasive grinding wheels for precision grinding structural ceramics  

SciTech Connect

This paper presents recent work performed at Lawrence Livermore National Laboratory to develop cost-effective, versatile and robust manufacturing methods for grinding precision features in structural ceramics using metal-bond, superabrasive grinding wheels. The developed processes include utilizing specialized, on-machine hardware to generate precision profiles onto grinding wheels using electrical-discharge machining (EDM) and a contoured rotating electrode. The production grinding processes are described, which were developed and used to grind various precision details into a host of structural ceramics such as Al{sub 2}O{sub 3}, Si{sub 3}N{sub 4}, and BeO. The methodologies, hardware and results of both creep-feed and cylindrical grinding are described. A discussion of imparted grinding damage and wheel wear is also presented.

Piscotty, M. A., LLNL

1997-08-01

101

Experimental research on vibration assisted EDM of micro-structures with non-circular cross-section  

Microsoft Academic Search

In micro-electrical discharge machining (EDM) of micro-structures with non-circular cross-section, the machining efficiency may be extraordinarily low due to the difficulties for dielectric liquid to flow and discharged debris to be removed out of the narrow discharge gap. To improve the machining efficiency and accuracy, the method of assisting workpiece vibration was introduced into such micro-EDM process using the tool

Hao Tong; Yong Li; Yang Wang

2008-01-01

102

A review on the conventional and micro-electrodischarge machining of tungsten carbide  

Microsoft Academic Search

The capability of machining intricate features with high dimensional accuracy in hard and difficult-to-cut material has made electrodischarge machining (EDM) process as an inevitable and one of the most popular non-conventional machining processes. In recent years, both EDM and micro-EDM processes are being used extensively in the field of mould making, production of dies, cavities and complex 3D structures using

M. P. Jahan; M. Rahman; Y. S. Wong

2011-01-01

103

Experimental Study on Influence of Process Variables on Crater Dimensions in Micro- EDM of {gamma}-Titanium Aluminide  

SciTech Connect

In the present work the effect of different dielectric mediums in micro-EDM of {gamma}-Titanium Aluminide alloy have been investigated. Experiments were conducted both in the absence (dry conditions) and in presence of dielectric (EDM oil).Circular craters were produced both in the presence and absence of dielectric fluid using varying micro-EDM process variables i.e. open circuit voltage, discharge capacitance, pulse frequency and pulse-on-time. Over cut was measured from optical microscope images using Image Analyzer software. Influences of process variables and optimal conditions for minimum over cut on crater dimensions were investigated. ANOVA test which shows that capacitance of RC circuit contributes significantly in crater formation followed by pulse frequency. Optical photographs exhibit that over cut are less in air medium compared to oil medium.

Mitra, S.; Paul, G.; Sarkar, S. [Department of Production Engineering, Jadavpur University, Kolkata-700032 (India); Nagahanumaiah [Micro Systems Technology Laboratory, CMERI, Durgapur (India)

2011-01-17

104

An on-line pulse trains analysis system of the wire-EDM process  

Microsoft Academic Search

Ignition delay time (Td) has been widely used to distinguish the abnormal discharges from the normal ones in wire electrical discharge machining (WEDM) process. In this paper an on-line analysis system for the causality of the Td data sequences was developed to evaluate the machining performance of WEDM process. The system is composed of a stand-alone Td processing circuitry and

Y. S. Liao; M. P. Cheng; K. W. Liao

2009-01-01

105

Chemical Aspects of Machining Processes  

Microsoft Academic Search

Machining processes used to create surfaces are influenced by the mechanical, thermal, and chemical loading in the contact zone. In addition, the tribo-physical and tribo-chemical interactions between the cutting tool, workpiece, metalworking fluid and surrounding medium have an influence on the properties of the resulting surface. In order to design efficient machining processes and control the chemical state of the

E. Brinksmeier; D. A. Lucca; A. Walter

2004-01-01

106

EDM Overview Motivation for EDM searches  

E-print Network

to study? · EDMs and Nuclear Physics ­ Radioactive atom EDMs ­ Proton EDM in storage ring ­ Neutron EDM contains more matter than antimatter." "A nonzero EDM would constitute a truly revolutionary discovery Physics Roadmap (2006) ZT Lu ANL EDMs continue to have strong discovery potential #12;What is the Origin

107

Modeling of electrical discharge machining process using back propagation neural network and multi-objective optimization using non-dominating sorting genetic algorithm-II  

Microsoft Academic Search

Present study attempts to model and optimize the complex electrical discharge machining (EDM) process using soft computing techniques. Artificial neural network (ANN) with back propagation algorithm is used to model the process. As the output parameters are conflicting in nature so there is no single combination of cutting parameters, which provides the best machining performance. A multi-objective optimization method, non-dominating

Debabrata Mandal; Surjya K. Pal; Partha Saha

2007-01-01

108

Application of genetic algorithm-based fuzzy logic control in wire transport system of wire-EDM machine  

Microsoft Academic Search

Wire tension as well as wire feed should be controlled tightly for the geometry and corner accuracy of wire-EDM. In this paper, a closed-loop wire tension control system for Micro-Wire-EDM is presented to guarantee a smooth wire transport and a constant tension value. In order to keep smooth wire transportation and avoid wire breakage during wire feeding, the reel roller

Mu-Tian Yan; Chi-Cheng Fang

2008-01-01

109

Bacillus subtilis EdmS (formerly PgsE) participates in the maintenance of episomes.  

PubMed

Extrachromosomal DNA maintenance (EDM) is an important process in molecular breeding and for various applications in the construction of genetically engineered microbes. Here we describe a novel Bacillus subtilis gene involved in EDM function called edmS (formerly pgsE). Functional gene regions were identified using molecular genetics techniques. We found that EdmS is a membrane-associated protein that is crucial for EDM. We also determined that EdmS can change a plasmid vector with an unstable replicon and worse-than-random segregation into one with better-than-random segregation, suggesting that the protein functions in the declustering and/or partitioning of episomes. EdmS has two distinct domains: an N-terminal membrane-anchoring domain and a C-terminal assembly accelerator-like structure, and mutational analysis of edmS revealed that both domains are essential for EDM. Further studies using cells of Bacillus megaterium and itsedmS (formerly capE) gene implied that EdmS has potential as a molecular probe for exploring novel EDM systems. PMID:23583563

Ashiuchi, Makoto; Yamashiro, Daisuke; Yamamoto, Kento

2013-09-01

110

The EDM surface: Topography, chemistry, and metallurgy  

SciTech Connect

The surface created by the electric discharge machining (EDM) process is of special interest because it has been shown to have a negative effect on the fatigue properties of many alloys. An understanding of the surface metallurgy and chemistry is important in predicting those alloys which are most susceptible to failure. Remedial actions, including thickness minimization, alteration, or removal of the surface layer are addressed.

Fuller, J.E.

1991-01-01

111

Surface damage in ZrB 2 -based composite ceramics induced by electro-discharge machining  

Microsoft Academic Search

Electro-conductive ZrB2-based composite ceramics, containing SiC and B4C, were machined with an electro-discharge machining (EDM) process. The EDMed surfaces were covered with resolidified ZrB2 layers. Many open pores and surface cracks were observed on the surfaces. The strength degradation of the ceramics caused by machining was evaluated by three point bending tests of the partially EDMed bending specimens. The effects

M. Nakamura; I. Shigematsu; K. Kanayama; Y. Hirai

1991-01-01

112

Development of a 3D touch trigger probe using micro spherical stylus machining by micro-EDM for micro-CMM  

NASA Astrophysics Data System (ADS)

This study develops a low-cost three-dimensional touch trigger probe for micro-CMM using micro spherical stylus machining by micro-EDM. The tip ball of the stylus, with a diameter smaller than 100 m, is made by a micro electro discharge machine with the method of wire electro discharge grinding (WEDG). The current study uses tungsten carbide (WC) as the material for the stylus. Experimental results show that, the tip ball roundness could amount to 2 m. Since the tip ball is not easily observable by naked eyes, we designed a micro imaging system to observe the probing in real time. This system is created with modified commercial webcam and microscope. The general design of the touch trigger probe is combined the stylus and suspension structure. When the stylus touches workpiece, it can be determined the time of probe trigger by measuring the motion of suspension structure. The stylus machined by micro-EDM was very fragile and the stylus handle of the tip ball was very thin. Therefore, the stylus handle bends easily that would result in the large measurement error or stylus break when the stylus touched workpiece. In this study we designed a measuring probe using a small chuck and an electrical circuit to measure the probe trigger. When the stylus touches the workpiece, the parallel circuit will switch on immediately and pick up the voltage variation of the resistor. Because the transistor always turns ON, it can avoid the problems of excessive energy and electrical noise.

Chu, Chih-Liang; Chen, Yi-Lin; Tai, Tzu-Yao; Liu, Yun-Hui; Chuang, Cheng-Hsin; Lu, Chin-Tu

2011-12-01

113

Neural-network-based modeling and optimization of the electro-discharge machining process  

Microsoft Academic Search

In this research, a new integrated neural-network-based approach is presented for the prediction and optimal selection of\\u000a process parameters in die sinking electro-discharge machining (EDM) with a flat electrode (planing mode). A 3642-size back-propagation\\u000a neural network is developed to establish the process model. The current (I), period of pulses (T), and source voltage (V)\\u000a are selected as network inputs. The

S. Assarzadeh; M. Ghoreishi

2008-01-01

114

Effects of Heat Treatments on the On-Line Service Life of a Press Die Manufactured by W-Edm  

NASA Astrophysics Data System (ADS)

Effects of heat treatments on the on-line service life of a press die manufactured by W-EDM are studied. In this work, four manufacturing processes for a press die are considered: (1) milling and then grinding, (2) wire-cut electric discharge machining (W-EDM), (3) low temperature heat treatment after W-EDM, and (4) high temperature heat treatment after W-EDM. On-line punching experiments for an automobile part of BL646-chain are performed. The amount of wear of the die and punch, roll-over and burnish depth in the punched chain are measured every 1,000 strokes. Overall productivities are carefully compared. Finally, it is concluded that heat treatment after W-EDM for a press die can enhance its on-line service life. Especially, high temperature heat treatment after W-EDM is very attractive as a fast and cheap manufacturing method for a press die.

Choi, Kye-Kwang; Lee, Yong-Shin

115

The benefits of using instantaneous energy to monitor the transient state of the wire EDM process  

Microsoft Academic Search

This paper deals with the implementation and analysis of real-time energy monitoring of the transient state of the wire electrical\\u000a discharge machining (WEDM) process. Recently, sparking frequency information has been applied to control of the WEDM process,\\u000a making more stable and efficient machining. Experimental results, however, show the limitations and insufficiency of that\\u000a method. Instead of using the sparking frequency

Shin Kwon; Min-Yang Yang

2006-01-01

116

State of the art in wire electrical discharge machining (WEDM)  

Microsoft Academic Search

Wire electrical discharge machining (WEDM) is a specialised thermal machining process capable of accurately machining parts with varying hardness or complex shapes, which have sharp edges that are very difficult to be machined by the main stream machining processes. This practical technology of the WEDM process is based on the conventional EDM sparking phenomenon utilising the widely accepted non-contact technique

K. H Ho; S. T Newman; S Rahimifard; R. D Allen

2004-01-01

117

Workpiece surface modification using electrical discharge machining  

Microsoft Academic Search

Electrical discharge machining (EDM) is a widely used process in the mould \\/ die and aerospace industries. Following a brief summary of the process, the paper reviews published work on the deliberate surface alloying of various workpiece materials using EDM. Details are given of operations involving powder metallurgy (PM) tool electrodes and the use of powders suspended in the dielectric

J Simao; H. G Lee; D. K Aspinwall; R. C Dewes; E. M Aspinwall

2003-01-01

118

Using ultra thin electrodes to produce micro-parts with wire-EDM  

Microsoft Academic Search

Small-sized tools and parts are gaining importance and share of the total product range Micromachining of Engineering Materials, 2002; Ann. CIRP 49 (2) (2000) 473]. An appropriate manufacturing process to cover the growing need for accurate small tools is electro-discharge-machining with thin wires (W-EDM). Until now only a few scientific works have been dealing with cutting by W-EDM using wires

F. Klocke; D. Lung; D. Thomaidis; G. Antonoglou

2004-01-01

119

Development of the Cylindrical Wire Electrical Discharge Machining Process, Part 1: Concept, Design, and Material Removal Rate  

Microsoft Academic Search

Results of applying the wire Electrical Discharge Machining (EDM) process to generate precise cylindrical forms on hard, difficult-to-machine materials are presented. The de- sign of a precise, flexible, and corrosion-resistant underwater rotary spindle is first intro- duced. A detailed spindle error analysis identifies the major sources of error at different frequency spectrum. The spindle has been added to a conventional

Albert J. Shih; Ronald O. Scattergood

2002-01-01

120

Shaping of steel mold surface of lens array by electrical discharge machining with single rod electrode.  

PubMed

We propose a method for fabricating a lens array mold by electrical discharge machining (EDM). In this method, the tips of rods are machined individually to form a specific surface, and then a number of the machined rods are arranged to construct an electrode for EDM. The repetition of the EDM process using the electrode enables a number of lens elements to be produced on the mold surface. The effectiveness of our proposed method is demonstrated by shaping a lens array mold made of stainless steel with 16 spherical elements, in which the EDM process with a single rod electrode is repeatedly conducted. PMID:25607880

Takino, Hideo; Hosaka, Takahiro

2014-11-20

121

Development and evaluation of an on-machine optical measurement device  

Microsoft Academic Search

Demand for fabricating micro-features such as fine holes, micro-cavity for injection moulding, and micro-pin using both conventional (turning, milling, etc.) and non-conventional edge detection method (EDM), wire cut EDM, etc.) processes is increasing significantly. To successfully achieve micro-machining, development of a miniature machine tool, process technology, and on-machine measurement is essential. However, in such tool-based micro-machining processes, proper tool shape

H. S. Lim; S. M. Son; Y. S. Wong; M. Rahman

2007-01-01

122

Microelectrode array fabrication by electrical discharge machining and chemical etching.  

PubMed

Wire electrical discharge machining (EDM), with a complementary chemical etching process, is explored and assessed as a method for developing microelectrode array assemblies for intracortically recording brain activity. Assembly processes based on these methods are highlighted, and results showing neural activity successfully recorded from the brain of a mouse using an EDM-based device are presented. Several structures relevant to the fabrication of microelectrode arrays are also offered in order to demonstrate the capabilities of EDM. PMID:15188855

Fofonoff, Timothy A; Martel, Sylvain M; Hatsopoulos, Nicholas G; Donoghue, John P; Hunter, Ian W

2004-06-01

123

High-speed micro electrode tool fabrication by a twin-wire EDM system  

NASA Astrophysics Data System (ADS)

This paper describes a new machining process which combines twin-electro-wire together with two electro discharge circuits to rapidly fabricate micro electrode tools. The results show that transistor electro discharge and RC electro discharge circuits coexist to fabricate micro tools with rough and finish machining both on the same machine. Compared to conventional wire electro discharge grinding (WEDG) technology, a twin-wire EDM system that combines rough and finish machining into one process allows the efficient fabrication of micro tools. This high-speed micro tool fabrication process can be applied not only to micro electrode machining but also to micro punching tool and micro probing tips machining.

Sheu, Dong-Yea

2008-10-01

124

Multi-objective optimization of the dry electric discharge machining process  

E-print Network

Dry Electric Discharge Machining (EDM) is an environment-friendly modification of the conventional EDM process, which is obtained by replacing the liquid dielectric by a gaseous medium. In this study, multi-objective optimization of dry EDM process has been done using the non dominated sorting genetic algorithm (NSGA II), with material removal rate (MRR) and surface roughness (Ra) as the objective functions. Experiments were conducted with air as dielectric to develop polynomial models of MRR and Ra in terms of the six input parameters: gap voltage, discharge current, pulse-on time, duty factor, air pressure and spindle speed. A Pareto-optimal front was then obtained using NSGA II. Analysis of the front was done to identify separate regions for finish and rough machining. Designed experiments were then conducted in these focused regions to verify the optimization results and to identify the region-specific characteristics of the process. Finishing conditions were obtained at low current, high pulse-on time an...

Saha, Sourabh

2009-01-01

125

?EDM-produced mechanical grippers for handling and assembly in microtechnology  

NASA Astrophysics Data System (ADS)

Two mechanical gripper types have been designed. Using a technology selection method, EDM was selected as the most appropriate fabrication technology for the designed grippers. Prototypes have been fabricated by wire EDM on a conventional machine. Increased attention has been paid to methodology of the production process and exploration of (mu) -EDM possibilities. The tolerance obtained is about 1 micrometers . The accuracy of the machined product is mainly determined by the quality of the electrode, its handling and the adjustment procedures. After fabrication the grippers were integrated onto a station for handling and assembly of microstructures. This paper provides a description of the used methodology in the production sequence and information on the machining process of the whole gripping system (gripper, holder, arrow). The results after the production are tested, analyzed and discussed.

Petrovic, Dragan; Popovic, Gordana; Chatzitheodoridis, Elias; Del Medico, Oscar; Almansa, Ana; Suemecz, Franz; Herbst, Peter; Brenner, Werner; Detter, Helmut; Duffait, Roland

2001-11-01

126

Microelectrode array fabrication by electrical discharge machining and chemical etching  

Microsoft Academic Search

Wire electrical discharge machining (EDM), with a complementary chemical etching process, is explored and assessed as a method for developing microelectrode array assemblies for intracortically recording brain activity. Assembly processes based on these methods are highlighted, and results showing neural activity successfully recorded from the brain of a mouse using an EDM-based device are presented. Several structures relevant to the

Timothy A. Fofonoff; Sylvain M. Martel; Nicholas G. Hatsopoulos; John P. Donoghue; Ian W. Hunter

2004-01-01

127

Precise Micro-Assembly Through an Integration of Micro-EDM and Nd-YAG  

Microsoft Academic Search

Micro-EDM (micro electro-discharge machining) integrated with Nd-YAG laser as a novel process for precise micro-assembly is\\u000a presented in the paper. In the integrated system the individual micro-parts assembled can be machined using micro-EDM, and\\u000a accurately moved to the desired position using ultra-precision motion control, and fuse bonded with a laser beam. This process\\u000a is demonstrated through two cases of a

H.-Y. Liang; C.-L. Kuo; J.-D. Huang

2002-01-01

128

Corrosion Resistance Analysis of Sintered NdFeB Magnets Using Ultrasonic-Aided EDM Method  

NASA Astrophysics Data System (ADS)

Sintered neodymium-iron-boron (NdFeB) permanent magnets are widely used in many fields because of their excellent magnetic property. However, their poor corrosion resistance has been cited as a potential problem that limits their extensive application. This paper presents an experimental investigation into the improvement of surface corrosion resistance with the ultrasonic-aided electrical discharge machining (U-EDM) method. A scanning electron microscope was used to analyze the surface morphology of recast layers formed through the EDM and U-EDM processes. The chemical structure and elements of these recast layers were characterized using x-ray diffraction and energy dispersive spectroscopy. Corrosion resistance was also studied by means of potentiodynamic polarization, electrochemical impedance spectroscopy, and immersion tests in 0.5 mol/L H2SO4 solution. Experimental results show that an amorphous structure was formed in the recast layer during the EDM and U-EDM processes and that this structure could improve the corrosion resistance of sintered NdFeB magnets. Moreover, the corrosion resistance of U-EDM-treated surface was better than that of the EDM-treated surface.

Li, L.; Wei, X. T.; Li, Z. Y.; Cheng, X.

2015-01-01

129

A study to achieve a fine surface finish in Wire-EDM  

Microsoft Academic Search

Many Wire-EDM machines have adopted the pulse-generating circuit using low power for ignition and high power for machining. However, it is not suitable for finishing process since the energy generated by the high-voltage sub-circuit is too high to obtain a desired fine surface, no matter how short the pulse-on time is assigned. For the machine used in this research, the

Y. S. Liao; J. T. Huang; Y. H. Chen

2004-01-01

130

Development of a computer assistant programming system for micro\\/nano milling tool fabrication by multi-axis wire EDM  

Microsoft Academic Search

Micro\\/nano milling tools are usually made of ultra hard materials. Wire EDM (electrical discharge machining) may be the best choice to fabricate these tools conveniently and efficiently. For micro\\/nano milling tools with complicated three-dimensional (3D) geometries, manually programming method is not applicable. The CAM (computer-aided manufacturing) systems existing in the market don't take the special WEDM (Wire EDM) processes for

Xiang Cheng; Zhigang Wang; Shigeru Kobayashi; Kazuo Nakamoto; Kazuo Yamazaki

2009-01-01

131

Micro-hole machining of carbide by electric discharge machining  

Microsoft Academic Search

This paper describes the characteristics of the micro-hole of carbide by electric discharge machining with a copper tool electrode. Electric discharge machining (EDM) is a thermal process that utilizes a spark discharge to melt a conductive material, the tool electrode being almost non-unloaded, because there is no direct contact between the tool electrode and the workpiece. Therefore, the process works

B. H. Yan; F. Y. Huang; H. M. Chow; J. Y. Tsai

1999-01-01

132

High-speed micro-electro-discharge machining  

Microsoft Academic Search

If the speed and precision of micro-electro-discharge machining (micro-EDM) processes can be significantly enhanced, then they have the potential to be used for a wide variety of micro- and meso-machining applications. Toward this end, a better understanding of the impacts the various machining parameters have on material removal has been established through a single discharge study of micro-EDM and a

Shawn P Moylan

2006-01-01

133

Using rapid prototyping to produce electrical discharge machining electrodes  

Microsoft Academic Search

Presents the background to and efforts being made to find a direct production route using rapid prototype (RP) parts as the electrodes for electrical discharge machining (EDM). It would have the double effect of unlocking the potential of the EDM die sinking process and expanding the role of RP in the production environment. Thin coated stereolithography (SL) models have been

Alan Arthur; Phillip Michael Dickens; Richard Charles Cobb

1996-01-01

134

Investigation of Wire Electrical Discharge Machining of Thin Cross-Sections and Compliant Mechanisms  

SciTech Connect

The wire electrical discharge machining (EDM) of cross-section with minimum thickness and compliant mechanisms is studied. Effects of EDM process parameters, particularly the spark cycle time and spark on-time on thin cross-section cutting of Nd-Fe-B magnetic material, carbon bipolar plate, and titanium are investigated. An envelope of feasible wire EDM process parameters is generated for the commercially pure titanium. The application of such envelope to select suitable EDM process parameters for micro feature generation is demonstrated. Scanning electron microscopy (SEM) analysis of EDM surface, subsurface, and debris are presented. SEM observations lead to a hypothesis based on the thermal and electrostatic stress induced fracture to explain the limiting factor for wire EDM cutting of thin-sections. Applications of the thin cross-section EDM cutting for manufacture of compliant mechanisms are discussed.

Miller, Scott F. [University of Michigan; Kao, Chen C. [University of Michigan; Shih, Albert J. [University of Michigan; Qu, Jun [ORNL

2005-01-01

135

Surface Improvement Using a Combination of Electrical Discharge Machining with Ball Burnish Machining Based on the Taguchi Method  

Microsoft Academic Search

This study investigates the feasibility of improving surface integrity via a novel combined process of electrical discharge\\u000a machining (EDM) with ball burnish machining (BBM) using the Taguchi method. To provide burnishing immediately after the EDM\\u000a process, ZrO2 balls were attached to the tool electrode in the experiments. To verify the optimal process, three observed values, i.e.\\u000a material removal rate, surface

Y. C. Lin; B. H. Yan; F. Y. Huang

2001-01-01

136

A Study on Micro Tooling and Moulding Processes of Polymer Can tilevers for Sensor Applications  

Microsoft Academic Search

Micro tooling and micro moulding studies have been carried out for the moulding process of polymer cantilevers for sensor and actuator applications. The microgrinding, elec- tro-discharge machining (EDM), and micro-EDM methods have been used for fabrication of micro cantilever tools. It has been found that the EDM and micro-EDM methods are not able to pro- duce cantilever inserts with good

J. Zhao; K. Ramesh; G. Chen; M. S. Yong

137

Influence of Surface Position along the Working Range of Conoscopic Holography Sensors on Dimensional Verification of AISI 316 Wire EDM Machined Surfaces  

PubMed Central

Conoscopic holography (CH) is a non-contact interferometric technique used for surface digitization which presents several advantages over other optical techniques such as laser triangulation. Among others, the ability for the reconstruction of high-sloped surfaces stands out, and so does its lower dependence on surface optical properties. Nevertheless, similarly to other optical systems, adjustment of CH sensors requires an adequate selection of configuration parameters for ensuring a high quality surface digitizing. This should be done on a surface located as close as possible to the stand-off distance by tuning frequency (F) and power (P) until the quality indicators Signal-to-Noise Ratio (SNR) and signal envelope (Total) meet proper values. However, not all the points of an actual surface are located at the stand-off distance, but they could be located throughout the whole working range (WR). Thus, the quality of a digitized surface may not be uniform. The present work analyses how the quality of a reconstructed surface is affected by its relative position within the WR under different combinations of the parameters F and P. Experiments have been conducted on AISI 316 wire EDM machined flat surfaces. The number of high-quality points digitized as well as distance measurements between different surfaces throughout the WR allowed for comparing the metrological behaviour of the CH sensor with respect to a touch probe (TP) on a CMM. PMID:24662452

Fernndez, Pedro; Blanco, David; Rico, Carlos; Valio, Gonzalo; Mateos, Sabino

2014-01-01

138

Influence of surface position along the working range of conoscopic holography sensors on dimensional verification of AISI 316 wire EDM machined surfaces.  

PubMed

Conoscopic holography (CH) is a non-contact interferometric technique used for surface digitization which presents several advantages over other optical techniques such as laser triangulation. Among others, the ability for the reconstruction of high-sloped surfaces stands out, and so does its lower dependence on surface optical properties. Nevertheless, similarly to other optical systems, adjustment of CH sensors requires an adequate selection of configuration parameters for ensuring a high quality surface digitizing. This should be done on a surface located as close as possible to the stand-off distance by tuning frequency (F) and power (P) until the quality indicators Signal-to-Noise Ratio (SNR) and signal envelope (Total) meet proper values. However, not all the points of an actual surface are located at the stand-off distance, but they could be located throughout the whole working range (WR). Thus, the quality of a digitized surface may not be uniform. The present work analyses how the quality of a reconstructed surface is affected by its relative position within the WR under different combinations of the parameters F and P. Experiments have been conducted on AISI 316 wire EDM machined flat surfaces. The number of high-quality points digitized as well as distance measurements between different surfaces throughout the WR allowed for comparing the metrological behaviour of the CH sensor with respect to a touch probe (TP) on a CMM. PMID:24662452

Fernndez, Pedro; Blanco, David; Rico, Carlos; Valio, Gonzalo; Mateos, Sabino

2014-01-01

139

High-speed micro-electro-discharge machining.  

SciTech Connect

When two electrodes are in close proximity in a dielectric liquid, application of a voltage pulse can produce a spark discharge between them, resulting in a small amount of material removal from both electrodes. Pulsed application of the voltage at discharge energies in the range of micro-Joules results in the continuous material removal process known as micro-electro-discharge machining (micro-EDM). Spark erosion by micro-EDM provides significant opportunities for producing small features and micro-components such as nozzle holes, slots, shafts and gears in virtually any conductive material. If the speed and precision of micro-EDM processes can be significantly enhanced, then they have the potential to be used for a wide variety of micro-machining applications including fabrication of microelectromechanical system (MEMS) components. Toward this end, a better understanding of the impacts the various machining parameters have on material removal has been established through a single discharge study of micro-EDM and a parametric study of small hole making by micro-EDM. The main avenues for improving the speed and efficiency of the micro-EDM process are in the areas of more controlled pulse generation in the power supply and more controlled positioning of the tool electrode during the machining process. Further investigation of the micro-EDM process in three dimensions leads to important design rules, specifically the smallest feature size attainable by the process.

Chandrasekar, Srinivasan Dr. (.School of Industrial Engineering, West Lafayette, IN); Moylan, Shawn P. (School of Industrial Engineering, West Lafayette, IN); Benavides, Gilbert Lawrence

2005-09-01

140

Improving Electrical Efficiency of Edm Power Supply  

NASA Astrophysics Data System (ADS)

This paper briefly presents the principal types of Pulse Generators for Electrical Discharge Machining and ways to improve electrical efficiency. A resonant converter with series-parallel LCC circuit, for EDM applications, was analyzed by PSpice simulation. The performances of EDM Power Supply were improved by adding an energy recovering - voltage limiter circuit. The shape of current pulse was changed by adding a supplementary MOSFET Switch in parallel with the gap. Two or more converters can be parallelized, in this way output current can be changed. A bloc-schema was conceived for EDM experimental set up

Toma, Emanoil; Simion, Carmen Mihaela

2014-11-01

141

Subnanosecond monitoring of micro-hole electrical discharge machining pulses and modeling of discharge ringing  

Microsoft Academic Search

Monitoring the gap voltage and current in micro-hole electrical discharge machining (EDM) using high-speed data acquisition with 0.5ns sampling period is conducted. The spark and arc pulses at three stages, namely electrode dressing, drilling, and penetration, of the micro-hole EDM are recorded. The EDM process parameters are setup to use negative polarity to blunt the electrode tip and positive polarity

C. C. Kao; Albert J. Shih

2006-01-01

142

Development of a high precision tabletop versatile CNC wire-EDM for making intricate micro parts  

NASA Astrophysics Data System (ADS)

The micro-electrical discharge machining (micro-EDM) process has been proved to be appropriate for making 3D micro parts that are difficult and even impossible to manufacture by other processes. In this paper a high precision tabletop CNC wire electrical discharge machine (wire EDM) designed specifically for machining complex shape micro parts or structures is developed. In the machine developed, a novel micro-wire-cutting mechanism is designed, an approach to control wire tension by magnetic force is proposed and a servo feed control strategy, in accordance with the measured gap voltage, is designed and implemented. To verify the functions and capabilities of the machine developed, several thick micro outer and internal spur gears and rack are machined. It shows that the taper angle along the wall or cavity of a part that appears when other micro-EDM processes are applied can be avoided. A very good dimensional accuracy of 1 m and a surface finish of Rmax equal to 0.64 m are achieved. The satisfactory cutting of a miniature 3D pagoda with a micro-hooked structure also reveals that the machine developed is versatile, and can be used as a new tool for making intricate micro parts.

Liao, Yunn-Shiuan; Chen, Shun-Tong; Lin, Chang-Sheng

2005-02-01

143

Modeling and analysis of white layer depth in a wire-cut EDM process through response surface methodology  

Microsoft Academic Search

A white layer is considered a major flaw on a workpiece surface machined with wire-cut electrical discharge machining (WEDM). In this paper, an attempt has been made to model the white layer depth through response surface methodology (RSM) in a WEDM process comprising a rough cut followed by a trim cut. An experimental plan for rotatable central composite design of

A. B. Puri; B. Bhattacharyya

2005-01-01

144

Investigation of silicon wafering by wire EDM  

Microsoft Academic Search

The new technology of silicon wafering by wire electrodischarge machining (EDM) was investigated to determine its mechanism of current-conducting and material removal. Target materials were n-type single-crystal silicon ingots with the resistivity of 715 cm?. It was found that the surface potential barrier of the semiconductors had a dominating effect on EDM cutting speed. Technological experiments were performed to determine

Y. F. Luo; C. G. Chen; Z. F. Tong

1992-01-01

145

Dry electrical discharge machining of cemented carbide  

Microsoft Academic Search

Dry electrical discharge machining (dry EDM) has characteristics of high work removal rate and low tool electrode wear ratio. Hence dry EDM is suitable for three-dimensional milling of difficult-to-cut materials, such as cemented carbide. We compared machining characteristics between dry EDM milling, oil EDM milling and oil die sinking EDM and found that dry EDM milling is most advantageous to

ZhanBo Yu; Takahashi Jun; Kunieda Masanori

2004-01-01

146

Machine Process Capability Information Through Six Sigma  

SciTech Connect

A project investigating details concerning machine process capability information and its accessibility has been conducted. The thesis of the project proposed designing a part (denoted as a machine capability workpiece) based on the major machining features of a given machine. Parts are machined and measured to gather representative production, short-term variation. The information is utilized to predict the expected defect rate, expressed in terms of a composite sigma level process capability index, for a production part. Presently, decisions concerning process planning, particularly what machine will statistically produce the minimum amount of defects based on machined features and associated tolerances, are rarely made. Six sigma tools and methodology were employed to conduct this investigation at AlliedSignal FM and T. Tools such as the thought process map, factor relationship diagrams, and components of variance were used. This study is progressing toward completion. This research study was an example of how machine process capability information may be gathered for milling planar faces (horizontal) and slot features. The planning method used to determine where and how to gather variation for the part to be designed is known as factor relationship diagramming. Components-of-variation is then applied to the gathered data to arrive at the contributing level of variation illustrated within the factor relationship diagram. The idea of using this capability information beyond process planning to the other business enterprise operations is proposed.

Lackner, M.F.

1998-03-13

147

Plasma characterization of dry ?-EDM  

Microsoft Academic Search

An attempt was made to characterize the dry microelectric discharge machining (?-EDM) plasma systematically by using optical\\u000a emission spectroscopy. In order to characterize the plasma and its parameters such as plasma temperature, electron density,\\u000a Debye length, and gamma parameter, the optical spectra were recorded for different energies and with different diameters of\\u000a tool electrode. From the recorded spectra, using line

S. Kanmani Subbu; G. Karthikeyan; J. Ramkumar; S. Dhamodaran

2011-01-01

148

Waveform Monitoring of Electric Discharge Machining by Wavelet Transform  

Microsoft Academic Search

The waveform affects the quality and mechanical performance of a workpiece during electric discharge machining (EDM). This\\u000a study uses the wavelet transform to process the waveform of EDM. The data of the waveform are obtained from the voltage and\\u000a current between the workpiece and the electrode of the electric discharge machine, and are then calculated by the wavelet\\u000a transform. The

S. F. Yu; B. Y. Lee; W. S. Lin

2001-01-01

149

Wire electrical discharge machining of metal bond diamond wheels for ceramic grinding  

Microsoft Academic Search

The application of cylindrical wire Electrical Discharge Machining (EDM) for profile truing of metal bond diamond wheels is presented. Instead of using the mechanical force to break the diamond and matrix in the grinding wheel, the wire EDM process uses the thermal energy or electrical sparks between the wire and rotating grinding wheel to remove the metal bond and form

Brian K. Rhoney; Albert J. Shih; Ronald O. Scattergood; Jeffery L. Akemon; Darryl J. Gust; Marion B. Grant

2002-01-01

150

Taguchi and Gauss elimination method: A dual response approach for parametric optimization of CNC wire cut EDM of PRAlSiCMMC  

Microsoft Academic Search

Machining parameters tables provided by the machine tool manufacturers often do not meet the operator requirements and sometimes\\u000a even do not provide efficient guidelines to manufacturing engineers. Hence, a suitable selection of machining parameters of\\u000a CNC wire cut electrical discharge machining (EDM) process is necessary. This paper present a reliable set of parameters that\\u000a demonstrate versatility, and numerous and diverse

A. Manna; B. Bhattacharyya

2006-01-01

151

Influence of Electrical Resistivity and Machining Parameters on Electrical Discharge Machining Performance of Engineering Ceramics  

PubMed Central

Engineering ceramics have been widely used in modern industry for their excellent physical and mechanical properties, and they are difficult to machine owing to their high hardness and brittleness. Electrical discharge machining (EDM) is the appropriate process for machining engineering ceramics provided they are electrically conducting. However, the electrical resistivity of the popular engineering ceramics is higher, and there has been no research on the relationship between the EDM parameters and the electrical resistivity of the engineering ceramics. This paper investigates the effects of the electrical resistivity and EDM parameters such as tool polarity, pulse interval, and electrode material, on the ZnO/Al2O3 ceramic's EDM performance, in terms of the material removal rate (MRR), electrode wear ratio (EWR), and surface roughness (SR). The results show that the electrical resistivity and the EDM parameters have the great influence on the EDM performance. The ZnO/Al2O3 ceramic with the electrical resistivity up to 3410 ?cm can be effectively machined by EDM with the copper electrode, the negative tool polarity, and the shorter pulse interval. Under most machining conditions, the MRR increases, and the SR decreases with the decrease of electrical resistivity. Moreover, the tool polarity, and pulse interval affect the EWR, respectively, and the electrical resistivity and electrode material have a combined effect on the EWR. Furthermore, the EDM performance of ZnO/Al2O3 ceramic with the electrical resistivity higher than 687 ?cm is obviously different from that with the electrical resistivity lower than 687 ?cm, when the electrode material changes. The microstructure character analysis of the machined ZnO/Al2O3 ceramic surface shows that the ZnO/Al2O3 ceramic is removed by melting, evaporation and thermal spalling, and the material from the working fluid and the graphite electrode can transfer to the workpiece surface during electrical discharge machining ZnO/Al2O3 ceramic. PMID:25364912

Ji, Renjie; Liu, Yonghong; Diao, Ruiqiang; Xu, Chenchen; Li, Xiaopeng; Cai, Baoping; Zhang, Yanzhen

2014-01-01

152

Influence of electrical resistivity and machining parameters on electrical discharge machining performance of engineering ceramics.  

PubMed

Engineering ceramics have been widely used in modern industry for their excellent physical and mechanical properties, and they are difficult to machine owing to their high hardness and brittleness. Electrical discharge machining (EDM) is the appropriate process for machining engineering ceramics provided they are electrically conducting. However, the electrical resistivity of the popular engineering ceramics is higher, and there has been no research on the relationship between the EDM parameters and the electrical resistivity of the engineering ceramics. This paper investigates the effects of the electrical resistivity and EDM parameters such as tool polarity, pulse interval, and electrode material, on the ZnO/Al2O3 ceramic's EDM performance, in terms of the material removal rate (MRR), electrode wear ratio (EWR), and surface roughness (SR). The results show that the electrical resistivity and the EDM parameters have the great influence on the EDM performance. The ZnO/Al2O3 ceramic with the electrical resistivity up to 3410 ?cm can be effectively machined by EDM with the copper electrode, the negative tool polarity, and the shorter pulse interval. Under most machining conditions, the MRR increases, and the SR decreases with the decrease of electrical resistivity. Moreover, the tool polarity, and pulse interval affect the EWR, respectively, and the electrical resistivity and electrode material have a combined effect on the EWR. Furthermore, the EDM performance of ZnO/Al2O3 ceramic with the electrical resistivity higher than 687 ?cm is obviously different from that with the electrical resistivity lower than 687 ?cm, when the electrode material changes. The microstructure character analysis of the machined ZnO/Al2O3 ceramic surface shows that the ZnO/Al2O3 ceramic is removed by melting, evaporation and thermal spalling, and the material from the working fluid and the graphite electrode can transfer to the workpiece surface during electrical discharge machining ZnO/Al2O3 ceramic. PMID:25364912

Ji, Renjie; Liu, Yonghong; Diao, Ruiqiang; Xu, Chenchen; Li, Xiaopeng; Cai, Baoping; Zhang, Yanzhen

2014-01-01

153

Modeling of wire EDM process using back propagation (BPN) and General Regression Neural Networks (GRNN)  

Microsoft Academic Search

In this paper the Artificial Neural Network (ANN) model is developed to predict the surface roughness in Wire Electrical Discharge Machining (WEDM) of Cr-Mo-V alloyed special steel, which is used in automobile industry. The neural network Models strained with experimental results conducted using L16 orthogonal array by considering the input parameters such as pulse duration, open voltage, wire speed and

P. V. B. Reddy; C. H. R. V. Kumar; K. H. Reddy

2010-01-01

154

Corner error simulation of rough cutting in wire EDM  

Microsoft Academic Search

This paper describes a novel simulation method for wire electrical discharge machining (EDM) in corner cut of rough cutting. In the simulation system, we analyzed the wire electrode vibration due to the reaction force acting on the wire electrode during the wire EDM, set up a geometrical model between the wire electrode path and NC path, and investigated the relationship

Fuzhu Han; Jie Zhang; Isago Soichiro

2007-01-01

155

Optimizing the EDM hole-drilling strain gage method for the measurement of residual stress  

Microsoft Academic Search

When using the electrical discharge machining (EDM) hole-drilling strain gage method to measure the residual stress within a component, the metallurgical transformation layer formed on the wall of the EDMed hole induces an extra stress, which can lead to significant measurement errors. Accordingly, the objective of the present work was to explore and determine the optimal EDM parameters which reduce

H. T. Lee; C. Liu

2009-01-01

156

Machining Process Control A machining force process of a turning operation that includes servomechanism dynamics is  

E-print Network

Machining Process Control QUESTION 1 A machining force process of a turning operation that includes controller and plot the time history of the feed and the force. Ignore the force process dynamics when designing the force controller. The initial feed is 0 mm, the desired closedloop time constant is 0.4 s

Landers, Robert G.

157

Development of the Cylindrical Wire Electrical Discharge Machining Process, Part 2: Surface Integrity and Roundness  

Microsoft Academic Search

This study investigates the surface integrity and roundness of parts created by the cylin- drical wire EDM process. A mathematical model for the arithmetic average surface roughness on the ideal surface of a cylindrical wire EDM workpiece is first derived. Effects of wire feed rate and part rotational speed on the surface finish and roundness for brass and carbide work-materials

Jun Qu; Albert J. Shih; Ronald O. Scattergood

2002-01-01

158

Current State and Prospect of MicroMachining  

Microsoft Academic Search

Micro-machining is a delicate process that requires pinpoint accuracy. Researchers in academia and industry worldwide are striving to develop efficient fabrication techniques for features in ranges of a few micrometers and even nanometers. The current leading micro-machining processes are micro drilling, micro milling, and micro turning, micro EDM, micro USM, micro LBM, micro ECM and LIGA. In this paper, the

Xiaoxia Li; Jiuhe Wang; Wen Li

2007-01-01

159

Micro-Hole Multi-Point Punching System Using Punch and Die Made by EDM  

NASA Astrophysics Data System (ADS)

In this research a multi-point micro punch and die system was developed. The process of electric discharge machining (EDM) was used to produce both the punch and die. The punches were machined from a 5 mm diameter tungsten and a 10 mm diameter tool steel round rods by wire electric discharge machining (WEDM), using a 200 m diameter wire electrode. The die holes were made using the punch as the electrode. The EDM process of the holes was carried out on a newly developed desktop EDM machine. The punch and die placed on a micro-die set and then on a micro press were used to produce micro-holes using an automatic control system developed for this process. Experiments to produce 50 m to 67 m square micro-holes on 50 m thick aluminum, 30 m thick copper and 20 m thick stainless steel foils were conducted. The capabilities of multi-point punching using the tungsten punch and a tool steel punch were examined and tungsten was chosen as the material of choice for making the punch tool. A scanning electron microscope confirmed that the holes produced are clean, and the sheared surfaces smooth. The punch tool showed no signs of deformation or cracks even after repeated punching.

Broomfield, Mark; Mori, Toshihiko; Mikuriya, Teruaki; Tachibana, Kazushi

160

Some investigations into the electric discharge machining of hardened tool steel using different electrode materials  

Microsoft Academic Search

Electric discharge machining (EDM), a non-traditional machining process, has been replacing drilling, milling, grinding and other traditional machining operations and is now a well-established machining option in many manufacturing industries throughout the world. Modern ED machinery is capable of machining geometrically complex or hard material components, that are precise and difficult-to-machine such as heat treated tool steels, composites, super alloys,

Shankar Singh; S. Maheshwari; P. C. Pandey

2004-01-01

161

Optimisation of EDM fast hole drilling for aerospace applications  

NASA Astrophysics Data System (ADS)

Electrical discharge machining (EDM) fast hole drilling is a thermo-electric manufacturing process in which material removal is achieved by sparks taking place between a tool electrode and the workpiece being drilled; both covered in dielectric fluid and connected to a generator delivering periodic pulses of energy at very high frequencies. There is no physical contact between the workpiece and the electrode, and the small gap separating them is maintained under servo control. EDM fast hole drilling plays a vital role in the aerospace industry. The operating temperatures of aero-engine often exceed the melting point of the materials used in its components. Hence, it is required to artificially cool different types of components including turbine blades. This is accomplished by directing bypass air into internal passages of the blade; the air flows continuality through small holes, having diameters ranging from 0.4 to 3mm and are drilled at steep angles to the baled surfaces. With EDM it is possible to drill these holes. The EDM drilling, however, operates with very high levels of relative electrode wear and high variations in cycle times making the process rather inconsistent. Using the DOE (Design of Experiments) approach, a series of studies have been carried out with the purpose of optimising the drilling process through the evaluation of water-based dielectric fluids and electrode materials, via analysis of drilling time, electrode wear, surface integrity, dimensional accuracy and costs. Factors such as the electrode length, geometry and dielectric flushing have also been studied. This work has shown that drilling times and electrode wear can be reduced by 50% and 35% respectively depending on the type of dielectric fluid/electrode material used and on the optimisation criteria employed. Significant reductions in the variations of drilling times have also been observed. Moreover, drilling time and electrode wear can be decreased by 165% and 25% respectively, depending on the electrode geometry employed.

Leao, F. N.

162

Process machine implementation using distributed objects  

Microsoft Academic Search

Manufacturing environments are moving away from stable, high volume environments to more flexible and lean environments. Industries objectives included improvement of the manufacturing process and the creation of a next generation computer integrated manufacturing (CIM) system architecture that could exploit new manufacturing technologies. This paper documents the implementation of the machine control and factory management portions of the CIM framework

Ahmed Hambaba; Evan McMasters

2002-01-01

163

Fabrication of a micro-tool in micro-EDM combined with co-deposited Ni SiC composites for micro-hole machining  

NASA Astrophysics Data System (ADS)

This paper presents an in situ process using a micro-tool in micro-electro-discharge-machining combined with co-deposited Ni-SiC composites to drill and finish micro-holes. During the machining process, a micro-tool is fabricated by wire electro-discharge grinding and electrodeposition. The experimental result shows that the suitable parameters obtained for fabricating micro-tools for Ni-SiC composite coatings are a current density of 7 A dm-2, positive ring hole diameter of 5 mm, SiC particle size of 4 m, SiC particle concentration of 10 g l-1, rotational speed of 15 rpm and surfactant cetyltrimethylammonium bromide concentration of 150 ppm. When using this method, the micro-tool is provided with a smooth Ni layer, uniform particle distribution and suitable particle adhesion quantity. Then, circular micro-holes are machined in high nickel alloy. Scanning electron microscopy micrographs and atomic force microscopy measurements show that micro-grinding can improve the surface roughness from 1.47 m Rmax to 0.462 m Rmax.

Hung, Jung-Chou; Wu, Wei-Chieh; Yan, Biing-Hwa; Huang, Fuang-Yuan; Wu, Kun-Ling

2007-04-01

164

Surface Integrity of Inconel 718 by Wire-EDM at Different Energy Modes  

NASA Astrophysics Data System (ADS)

Inconel alloys including IN 718 alloy are widely used in turbomachinery industry due to their superior mechanical properties. Inconel alloys are very difficult to machine using cutting and grinding. Wire electrical discharge machining (W-EDM) is an alternative process to manufacture complex Inconel parts. However, little research has been done on surface integrity by W-EDMed IN 718. This study focuses on surface integrity of IN 718 by W-EDM at different modes of discharge energy. The results show that the EDMed surface topography shows dominant coral reef microstructures at high energy mode, while random microvoids are dominant at low energy modes. The average roughness can be significantly reduced at low energy mode. A thick white layer is predominantly discontinuous and non-uniform at relative high energy modes. Microvoids are confined within the thick white layers and no microcracks were found in the subsurface. A thin white layer by trim cut at low energy mode becomes continuous, uniform, and is free of voids. Compared to the bulk, white layers have dramatic reduction in microhardness. In addition, surface alloying from wire electrode and water dielectric is obvious in main cut, but it can be minimized in trim cuts.

Li, L.; Wei, X. T.; Guo, Y. B.; Li, W.; Liu, J. F.

2014-08-01

165

Ultrasonic and electric discharge machining to deep and small hole on titanium alloy  

Microsoft Academic Search

Being a difficult-to-cut material, titanium alloy suffers poor machinability for most cutting process, let alone the drilling of small and deep holes using traditional machining methods. Although electric discharge machining (EDM) is suitable to handle titanium alloys, it is not ideal for small and deep holes due to titanium alloys low heating conductivity and high tenacity. This paper introduces ultrasonic

Zhao Wansheng; Wang Zhenlong; Di Shichun; Chi Guanxin; Wei Hongyu

2002-01-01

166

Abstract--Laser engraving is a manufacturing method for those applications where previously Electrical Discharge Machining  

E-print Network

Electrical Discharge Machining (EDM) was the only choice. Laser engraving technology removes material layer the influence of the process parameters on the surface quality when machined by laser engraving. The examined advantages of this method compared to traditional machining, such as: no mechanical contact with the surface

Aristomenis, Antoniadis

167

Pin-plate micro assembly by integrating micro-EDM and Nd-YAG laser  

Microsoft Academic Search

This paper presents a novel technology that applies the principle of Molten-Separation Joint (MSJ) from the micro-part back to perform precise micro assembly. This has been realized by using a hybrid process that integrates micro-EDM and Nd-YAG laser welding on a single machine to fabricate micro parts and complete precise micro assembly. To demonstrate this novel technology, we used this

Jing-Dae Huang; Chia-Lung Kuo

2002-01-01

168

The Neutron EDM Experiment  

E-print Network

The neutron EDM experiment has played an important part over many decades in shaping and constraining numerous models of CP violation. This review article discusses some of the techniques used to calculate EDMs under various theoretical scenarios, and highlights some of the implications of EDM limits upon such models. A pedagogical introduction is given to the experimental techniques employed in the recently completed ILL experiment, including a brief discussion of the dominant systematic uncertainties. A new and much more sensitive version of the experiment, which is currently under development, is also outlined.

P. G. Harris

2007-12-05

169

Surface characteristics and damage of monocrystalline silicon induced by wire-EDM  

NASA Astrophysics Data System (ADS)

Wire-EDM has recently shown itself as an alternative approach for slicing silicon and other semiconductor materials without the presence of significant chipping as normally found in the traditional machining processes. However, the intensive electrical spark between a wire electrode and silicon can cause damage to the cut surface and subsurface in micro and nano-scale aspects. This paper presents the influence of major process parameters on the cut surface characteristics and damage in the wire-EDMing of silicon. An n-type monocrystalline silicon wafer was cut under different spark energy densities, duty cycles and dielectric flushing rates. Poor cut surface quality and high amount of electrode material deposition were obtained when low spark energy density, small duty cycle and low dielectric flushing rate were applied. Moreover, the amorphous and defective crystal structures of silicon were apparent under the low spark energy condition. The interactions between the wire-EDMing parameters and cut surface characteristics drawn in this study could have significances for the further development of EDM technology towards the fine-scale and damage-free processing of semiconductor materials.

Punturat, Jiraporn; Tangwarodomnukun, Viboon; Dumkum, Chaiya

2014-11-01

170

Characterisation of integrated WAAM and machining processes  

NASA Astrophysics Data System (ADS)

This research describes the process of manufacturing and machining of wire and arc additive manufactured (WAAM) thin wall structures on integrated and non-integrated WAAM systems. The overall aim of this thesis is to obtain a better understanding of deposition and machining of WAAM wall parts through an integrated system. This research includes the study of the comparison of deposition of WAAM wall structures on different WAAM platforms, namely an Integrated SAM Edgetek grinding machine, an ABB robot and a Friction Stir Welding (FSW) machine. The result shows that WAAM is a robustly transferable technique that can be implemented across a variety of different platforms typically available in industry.. For WAAM deposition, a rise in output repeatedly involves high welding travel speed that usually leads to an undesired humping effect. Part of the objectives of this work was to study the travel speed limit for humping. The findings from this research show that the travel speed limit falls within a certain region at which humping starts to occur. One of the objectives of this thesis was to study the effect of lubricants during sequential and non-sequential machining/deposition of the WAAM parts. Conventional fluid lubricants and solid lubricants were used. In addition, the effect of cleaning of deposited wall samples with acetone was also studied. A systematic study shows that a significant amount of solid lubricant contamination can be found in the deposited material. Furthermore, the results indicate that even cleaning of the wire and arc additive manufactured surfaces with acetone prior to the weld deposition can affect the microstructure of the deposited material..

Adebayo, Adeyinka

171

Maps of Dipersions for Machining Processes  

E-print Network

During the products design, the design office defines dimensional and geometrical parameters according to the use criteria and the product functionality. The manufacturing department must integrate the manufacturing and the workpiece position dispersions during the choice of tools and machines operating modes and parameters values to respect the functional constraints. In this paper, we suggest to model the turning dispersions taking into account not only geometrical specifications of position or orientation but also the experience of method actors. A representation using the principle of know-how maps in two or three dimensions is privileged. The most interesting aspect is that these maps include tacit and explicit knowledge. An experimental study realized on a machine tool (HES 300) allows to elaborate knowledge maps especially for the turning process.

Valry Wolff; Arnaud Lefebvre; J. Renaud

2008-03-03

172

Micro-EDM Milling of Micro Platinum Hemisphere  

Microsoft Academic Search

Micro-EDM milling has become one of the powerful means of 3D micromachining for MEMS. However, for micro- EDM milling, there isn't a general electrode wear compensation strategy matched to arbitrary materials of workpiece and electrode. In this paper, the machinability of platinum metal is evaluated by taking latent heat of fusion and evaporation into account firstly. And then, a general

Guanrong Hang; Guohui Cao; Zaicheng Wang; Jing Tang; Zhenlong Wang; Wansheng Zhao

2006-01-01

173

Electrode Wear Process in Electrical Discharge Machinings  

Microsoft Academic Search

This paper deals with a synthetic consideration of electrode wear phenomena in electrical discharge machining. Time dependance of an electrode shape was observed through on-the-machine measurement. While the electrode wears at the edge portion in the beginning of machining, it grows at the flat portion in the longitudinal direction. In the stationary state of machining, the wear rate of an

Naotake Mohri; Masayuki Suzuki; Masanori Furuya; Nagao Saito; Akira Kobayashi

1995-01-01

174

Performance and Surface Integrity of Ti6Al4V After Sinking EDM with Special Graphite Electrodes  

NASA Astrophysics Data System (ADS)

Titanium and its alloys have high chemical reactivity with most of the cutting tools. This makes it difficult to work with these alloys using conventional machining processes. Electrical discharge machining (EDM) emerges as an alternative technique to machining these materials. In this work, it is investigated the performance of three special grades of graphite as electrodes when ED-Machining Ti6Al4V samples under three different regimes. The main influences of electrical parameters are discussed for the samples material removal rate, volumetric relative wear and surface roughness. The samples surfaces were evaluated using SEM images, microhardness measurements, and x-ray diffraction. It was found that the best results for samples material removal rate, surface roughness, and volumetric relative wear were obtained for the graphite electrode with 10-?m particle size and negative polarity. For all samples machined by EDM and characterized by x-ray (XRD), it was identified the presence of titanium carbides. For the finish EDM regimes, the recast layer presents an increased amount of titanium carbides compared to semi-finish and rough regimes.

Amorim, Fred L.; Stedile, Leandro J.; Torres, Ricardo D.; Soares, Paulo C.; Henning Laurindo, Carlos A.

2014-04-01

175

Solid modeling of 4-axis wire EDM cut geometry  

Microsoft Academic Search

NC verification has been widely used in milling and turning machining, but the implementation of NC verification for wire electrical discharge machine (wire EDM) has received little attention, made difficult by the characteristics of geometry cut by the thin wire. For an NC verification system, the speed and the accuracy of are two of the most critical issues. In this

Chonglin Liu; Donald M. Esterling

1997-01-01

176

From NLP (Natural Language Processing) to MLP (Machine Language Processing)  

Microsoft Academic Search

\\u000a Natural Language Processing (NLP) in combination with Machine Learning techniques plays an important role in the field of\\u000a automatic text analysis. Motivated by the successful use of NLP in solving text classification problems in the area of e-Participation\\u000a and inspired by our prior work in the field of polymorphic shellcode detection we gave classical NLP-processes a trial in\\u000a the special

Peter Teufl; Udo Payer; Guenter Lackner

2010-01-01

177

Evaluation of machining dispersions for turning process  

E-print Network

In this article we propose to extend the model of simulation of dispersions in turning based on the geometrical specifications. Our study is articulated around two trends of development: the first trend relates to the geometrical model. The geometrical model suggested must allow a follow-up of the geometry of the part during the simulation of machining. It is thus a question of carrying out a systematic treatment of the whole dimensioning and tolerancing process while being based on the principles of the \\DeltaL method. We also planned to integrate this type of specification in the model of simulation of machining suggested. It is more generally a question of extending the traditional model for better taking into account the multi axis specification of coaxiality and perpendicularity on the turned workpieces. The second trend of our study relates to the widening of the field of application of the model. We propose to extend the field of application of the model by taking into account the modifications of several parameters of the manufacturing process plans, likely to involve variations of dispersions.

Arnaud Lefebvre; Valery Wolff

2008-03-03

178

Searching for the electron EDM in a storage ring  

Microsoft Academic Search

Searches for permanent electric dipole moments (EDM) of fundamental particles have been underway for more than 50 years with null results. Still, such searches are of great interest because EDMs arise from radiative corrections involving processes that violate parity and time-reversal symmetries, and through the CPT theorem, are sensitive to CP-violation. New models of physics beyond the standard model predict

D. Kawall

2011-01-01

179

Effect of electrical discharge machining on surface characteristics and machining damage of AISI D2 tool steel  

Microsoft Academic Search

In this work the electrical discharge machining (EDM) of AISI D2 tool steel was investigated. The surface characteristics and machining damage caused by EDM were studied in terms of machining parameters. Based on the experimental data, an empirical model of the tool steel was also proposed. A new damage variable was used to study the EDM damage. The workpiece surface

Y. H. Guu; H. Hocheng; C. Y. Chou; C. S. Deng

2003-01-01

180

Integration of laser processing in machine tools and their economy  

NASA Astrophysics Data System (ADS)

The demand of machine users towards the complete processing of a workpiece in one setting requires the use of different processing technologies in one machine. In the past years lasers have found new applications in production engineering as a tool for surface modification, cutting, welding and marking. By combination of conventional metal cutting technologies with laser processes in one machine, the complete processing of a workpiece with different technologies in one setting can be realized. The advantages are the processing in one setting and the reduction of material flow between the production machines. The possibility of integrating lasers for material processing in a cutting machine are examined. Processing technology as well as different constructive solutions depending on the type of machine used and integration method are evaluated. Parallel to this approach, examinations of the economy of these systems are carried out.

Krastel, Klaus; Drechsel, Jan

1999-05-01

181

Integration of laser processing in machine tools and their economy  

NASA Astrophysics Data System (ADS)

The demand of machine users towards the complete processing of a workpiece in one setting requires the use of different processing technologies in one machine. In the past years lasers have found new applications in production engineering as a tool for surface modification, cutting, welding and marking. By combination of conventional metal cutting technologies with laser processes in one machine, the complete processing of a workpiece with different technologies in one setting can be realized. The advantages are the processing in one setting and the reduction of material flow between the production machines. The possibility of integrating lasers for material processing in a cutting machine are examined. Processing technology as well as different constructive solutions depending on the type of machine used and integration method are evaluated. Parallel to this approach, examinations of the economy of these systems are carried out.

Krastel, Klaus; Drechsel, Jan

1997-09-01

182

On a Parallel Machine Scheduling Problem with Equal Processing Times  

E-print Network

United Institute of Informatics Problems, Surganova St. 6, 220012 Minsk, Belarus kravch to be processed on m identical parallel machines. For each job Jj, j = 1, . . . , n, a processing time pj = p of processing is not allowed, i.e. the processing of any job started at time t on one of the identical machines

Magdeburg, Universitt

183

Study of an ultrafine w-EDM technique  

NASA Astrophysics Data System (ADS)

A precision ultrafine w-EDM (wire electrical discharge machining) technique specifically for machining intricate parts and structures is developed in this paper. A thumb-sized and versatile w-EDM device equipped with a complete control system for wire tension (ultrafine tungsten wire of 13 m diameter) is designed and employed for the study of ultrafine w-EDM. The tension of the wire electrode is controlled by magnetic repulsive force to steady the wire during machining. Ultrafine wire cutting can be conducted in vertical-, horizontal- or slantwise-wire arrangements. Via some experiments, optimal machining conditions including discharge capacitance, feed rate, wire tension and the appropriate design for the w-EDM device are obtained. Two miniature samples including a micro of Taipei's landmark 101 building and a micro relay are fabricated and the feasibility of the proposed approach is verified. It is confirmed that the ultrafine w-EDM technique using an ultrafine tungsten wire of 13 m was realized successfully.

Chen, Shun-Tong; Yang, Hong-Ye; Du, Chih-Wei

2009-11-01

184

The effect of microstructure on fatigue performance of Ti-6Al-4V alloy after EDM surface treatment for application in orthopaedics.  

PubMed

Three different microstructures--equiaxed, bi-modal and coarse lamellar--are prepared from Ti-6Al-4V alloy. Electric discharge machining (EDM) with a high peak current (29 A) is performed in order to impose surface roughness and modify the chemical composition of the surface. Detailed scanning electron microscopy (SEM) investigation revealed a martensitic surface layer and subsurface heat affected zone (HAZ). EDX measurements showed carbon enriched remnants of the EDM process on the material surface. Rotating bending fatigue tests are undertaken for EDM processed samples for all three microstructures and also for electropolished-benchmark-samples. The fatigue performance is found to be rather poor and not particularly dependent on microstructure. The bi-modal microstructure shows a slightly superior high cycle fatigue performance. This performance can be further improved by a suitable heat treatment to an endurance limit of 200 MPa. PMID:22098894

Strsk, Josef; Jane?ek, Milo; Harcuba, Petr; Bukovina, Michal; Wagner, Lothar

2011-11-01

185

Artificial Neural Network Prediction of Material Removal Rate in Electro Discharge Machining  

Microsoft Academic Search

Thermal erosion theory is widely accepted as an explanation of the erosion process in electro-discharge machining (EDM). Theoretical models are based on the solution of the transient heat conduction equation, which is modeled considering suitable assumptions with appropriate initial and boundary conditions. The closed form solutions result only after considering too many assumptions, which are far from actual machining conditions.

Deepak Kumar Panda; Rajat Kumar Bhoi

2005-01-01

186

ELECTRODISCHARGE MACHINING OF TRANSFORMATION TOUGHENED ZrO - NbC CERAMIC COMPOSITE  

Microsoft Academic Search

Electroconductive transformation toughened ZrO2 and NbC ceramic composite was machined with an electro-discharge machining (EDM) method. Effects of EDM conditions on roughness of machined surfaces were examined. Surface damage caused during machining was evaluated with flexural strength of machined specimens. Fracture surfaces of EDMed bending specimens were observed by scanning electron microscopy (SEM).It was observed that the strength of EDMed

M. Nakamura; K. Kanayama; Y. Hirai

1989-01-01

187

Micro Electro Discharge Machining of Electrically Nonconductive Ceramics  

NASA Astrophysics Data System (ADS)

EDM is a known process for machining of hard and brittle materials. Due to its noncontact and nearly forceless behaviour, it has been introduced into micro manufacturing and through constant development it is now an important means for producing high-precision micro geometries. One restriction of EDM is its limitation to electrically conducting materials. Today many applications, especially in the biomedical field, make use of the benefits of ceramic materials, such as high strength, very low wear and biocompatibility. Common ceramic materials such as Zirconium dioxide are, due to their hardness in the sintered state, difficult to machine with conventional cutting techniques. A demand for the introduction of EDM to these materials could so far not be satisfied because of their nonconductive nature. At the Chemnitz University of Technology and the Fraunhofer IWU, investigations in the applicability of micro-EDM for the machining of nonconductive ceramics are being conducted. Tests are undertaken using micro-EDM drilling with Tungsten carbide tool electrodes and ZrO2 ceramic workpieces. A starting layer, in literature often referred to as `assisting electrode' is used to set up a closed electric circuit to start the EDM process. Combining carbon hydride based dielectric and a specially designed low-frequency vibration setup to excite the workpiece, the process environment can be held within parameters to allow for a constant EDM process even after the starting layer is machined. In the experiments a cylindrical 120 ?m diameter Tungsten carbide tool electrode and Y2O3- and MgO- stabilized ZrO2 worpieces are used. The current and voltage signals of the discharges within the different stages of the process (machining of the starting layer, machining of the base material, transition stage) are recorded and their characteristics compared to discharges in metallic material. Additionally, the electrode feed is monitored. The influences of the process parameters are analysed with regard to the discharge type, electrode wear and process speed. Using the found parameters, micro geometries can be successfully machined into nonconductive Y2O3- and MgO- stabilized ZrO2 ceramic by means of micro-EDM.

Schubert, A.; Zeidler, H.; Wolf, N.; Hackert, M.

2011-05-01

188

Micro Electro Discharge Machining of Electrically Nonconductive Ceramics  

SciTech Connect

EDM is a known process for machining of hard and brittle materials. Due to its noncontact and nearly forceless behaviour, it has been introduced into micro manufacturing and through constant development it is now an important means for producing high-precision micro geometries. One restriction of EDM is its limitation to electrically conducting materials.Today many applications, especially in the biomedical field, make use of the benefits of ceramic materials, such as high strength, very low wear and biocompatibility. Common ceramic materials such as Zirconium dioxide are, due to their hardness in the sintered state, difficult to machine with conventional cutting techniques. A demand for the introduction of EDM to these materials could so far not be satisfied because of their nonconductive nature.At the Chemnitz University of Technology and the Fraunhofer IWU, investigations in the applicability of micro-EDM for the machining of nonconductive ceramics are being conducted. Tests are undertaken using micro-EDM drilling with Tungsten carbide tool electrodes and ZrO{sub 2} ceramic workpieces. A starting layer, in literature often referred to as 'assisting electrode' is used to set up a closed electric circuit to start the EDM process. Combining carbon hydride based dielectric and a specially designed low-frequency vibration setup to excite the workpiece, the process environment can be held within parameters to allow for a constant EDM process even after the starting layer is machined. In the experiments a cylindrical 120 {mu}m diameter Tungsten carbide tool electrode and Y{sub 2}O{sub 3}- and MgO- stabilized ZrO{sub 2} worpieces are used. The current and voltage signals of the discharges within the different stages of the process (machining of the starting layer, machining of the base material, transition stage) are recorded and their characteristics compared to discharges in metallic material. Additionally, the electrode feed is monitored. The influences of the process parameters are analysed with regard to the discharge type, electrode wear and process speed.Using the found parameters, micro geometries can be successfully machined into nonconductive Y{sub 2}O{sub 3}- and MgO- stabilized ZrO{sub 2} ceramic by means of micro-EDM.

Schubert, A. [Chair Micromanufacturing Technology, Faculty of Mechanical Engineering, Chemnitz University of Technology, 09107 Chemnitz (Germany); Fraunhofer Institute for Machine Tools and Forming Technology IWU, 09126 Chemnitz (Germany); Zeidler, H.; Hackert, M. [Chair Micromanufacturing Technology, Faculty of Mechanical Engineering, Chemnitz University of Technology, 09107 Chemnitz (Germany); Wolf, N. [Fraunhofer Institute for Machine Tools and Forming Technology IWU, 09126 Chemnitz (Germany)

2011-05-04

189

Electrical-Discharge Machining With Additional Axis  

NASA Technical Reports Server (NTRS)

Proposed electrical-discharge-machining (EDM) apparatus uses moveable vertical wire as electrode. Wire positionable horizontally along one axis as it slides vertically past workpiece. Workpiece indexed in rotation about horizontal axis. Because of symmetry of parts, process used to make two such parts at a time by defining boundary between them. Advantages: cost of material reduced, imparts less residual stress to workpiece, and less time spent machining each part when parts produced in such symmetrical pairs.

Malinzak, Roger M.; Booth, Gary N.

1991-01-01

190

Study of micro-EDM plasmas  

NASA Astrophysics Data System (ADS)

Micro Electrical Discharge Machining (micro-EDM) is a plasma-assisted process for the manufacturing of micro-components in high-hardness conductive materials. The removal of material is the result of a sum of dc discharges, produced within a point to plane system of electrodes immersed in a dielectric fluid, whose electric disruption with the development of plasma-currents can be induced by imposing a threshold voltage. To better understand the interaction between the micro-plasma and the material, we have designed and build an experimental setup for the production of single-discharges, characterized by a constant voltage-current operation point. The device allows the ignition of resistive plasmas in air/water at different pulse-times (100--3200 ?s), currents (1-20 A for 75-250 V), polarities and gap-sizes (0,5-25 ?m), and the changes in these work conditions can be correlated to the type and size of the craters produced. The micro-plasma electron density ne is measured using the Stark broadening of the H? atomic line. First results give ne 10^16 -- 10^17 cm^3, in agreement with estimates obtained from an electrical circuit model of the discharge.

Braganca, I. M. F.; Rosa, P. A. R.; Dias, F. M.; Alves, L. L.

2011-11-01

191

Energy Survey of Machine Tools: Separating Power Information of the Main Transmission System During Machining Process  

NASA Astrophysics Data System (ADS)

The major power information of the main transmission system in machine tools (MTSMT) during machining process includes effective output power (i.e. cutting power), input power and power loss from the mechanical transmission system, and the main motor power loss. These information are easy to obtain in the lab but difficult to evaluate in a manufacturing process. To solve this problem, a separation method is proposed here to extract the MTSMT power information during machining process. In this method, the energy flow and the mathematical models of major power information of MTSMT during the machining process are set up first. Based on the mathematical models and the basic data tables obtained from experiments, the above mentioned power information during machining process can be separated just by measuring the real time total input power of the spindle motor. The operation program of this method is also given.

Liu, Shuang; Liu, Fei; Hu, Shaohua; Yin, Zhenbiao

192

Effect of hole geometry and Electric-Discharge Machining (EDM) on airflow rates through small diameter holes in turbine blade material  

NASA Technical Reports Server (NTRS)

The effects of two design parameters, electrode diameter and hole angle, and two machine parameters, electrode current and current-on time, on air flow rates through small-diameter (0.257 to 0.462 mm) electric-discharge-machined holes were measured. The holes were machined individually in rows of 14 each through 1.6 mm thick IN-100 strips. The data showed linear increase in air flow rate with increases in electrode cross sectional area and current-on time and little change with changes in hole angle and electrode current. The average flow-rate deviation (from the mean flow rate for a given row) decreased linearly with electrode diameter and increased with hole angle. Burn time and finished hole diameter were also measured.

Hippensteele, S. A.; Cochran, R. P.

1980-01-01

193

Fabrication of a micro-spherical tool in EDM combined with Ni-diamond co-deposition  

NASA Astrophysics Data System (ADS)

This paper demonstrates a novel fabrication process using electro-discharge-machining (EDM) combined with co-deposited Ni-diamond composites to build a unique micro-spherical diamond tool. A micro tool is made by a hybrid process including wire electro-discharge grinding, EDM spherical forming, electrochemical machining and co-deposition. Tungsten carbide material is used as the tool substrate. The influence of EDM spherical forming and co-deposition parameters on the tool geometry is presented. The experimental result shows a unique micro-spherical diamond tool can be successfully built with suitable spherical forming parameters that are a peak current of 3 A, pulse duration of 40 s and spindle rotational speed of 0 rpm in the air, and in Ni-diamond co-deposition are a current density of 7 A dm-2, diamond particle size of 3 m, diamond particle concentration of 10 g l-1 and rotational speed of 15 rpm. When using this method, the micro tool has a better geometric shape, uniform particle distribution and suitable particle adhesion quantity. The tool is tested to machine a mold provided with a micro-spherical cavity in a high nickel alloy.

Hung, Jung-Chou; Lien, Shao-Chun; Lin, Jui-Kuan; Huang, Fuang-Yuan; Yan, Biing-Hwa

2008-04-01

194

The study on the atomic force microscopy base nanoscale electrical discharge machining.  

PubMed

This study proposes an innovative atomic force microscopy (AFM) based nanoscale electrical discharge machining (AFM-based nanoEDM) system which combines an AFM with a self-produced metallic probe and a high-voltage generator to create an atmospheric environment AFM-based nanoEDM system and a deionized water (DI water) environment AFM-based nanoEDM system. This study combines wire-cut processing and electrochemical tip sharpening techniques on a 40-m thick stainless steel sheet to produce a high conductive AFM probes, the production can withstand high voltage and large current. The tip radius of these probes is approximately 40 nm. A probe test was executed on the AFM using probes to obtain nanoscales morphology of Si wafer surface. The silicon wafer was as a specimen to carry out AFM-base nanoEDM process in atmospheric and DI water environments by AFM-based nanoEDM system. After experiments, the results show that the atmospheric and DI water environment AFM-based nanoEDM systems operate smoothly. From experimental results, it can be found that the electric discharge depth of the silicon wafer at atmospheric environments is a mere 14.54 nm. In a DI water environment, the depth of electric discharge of the silicon wafer can reach 25.4 nm. This indicates that the EDM ability of DI water environment AFM-based nanoEDM system is higher than that of atmospheric environment AFM-based nanoEDM system. After multiple nanoEDM process, the tips become blunt. After applying electrochemical tip sharpening techniques, the tip radius can return to approximately 40 nm. Therefore, AFM probes produced in this study can be reused. PMID:21898457

Huang, Jen-Ching; Chen, Chung-Ming

2012-01-01

195

Miller, Scott Franklin. Wire Electro-Discharge Machining of Advanced Engineering Materials. (Under the direction of Dr. Albert Shih)  

E-print Network

Abstract Miller, Scott Franklin. Wire Electro-Discharge Machining of Advanced Engineering Materials for Wire Electrical Discharge Machining (WEDM) of new advanced engineering materials and for truing to measure temperatures generated during the EDM process using infrared spectrometry on three different

Shih, Albert J.

196

RSM model to evaluate material removal rate in EDM of Ti-5Al-2.5Sn using graphite electrode  

NASA Astrophysics Data System (ADS)

The usage of electrical discharge machining (EDM) is increasing gradually owing to its capability to cut precisely, geometrically complex material regardless hardness. Many process parameters greatly affect the EDM performance and complicated mechanism of the process result the lag of established theory. Hence, it becomes important to select the proper parameter set for different machining stages in order to promote efficiency. In view of these barriers, it is attempted to establish a model which can accurately predict the material removal rate (MRR) of titanium alloy by correlating the process parameter. Effect of the parameters on MRR is investigated as well. Experiment is conducted utilizing the graphite electrode maintaining negative polarity. Analysis and modelling is carried out based on design of experiment as well as response surface methodology. The agreeable accuracy is obtained and thus the model can become a precise tool setting the EDM process cost effective and efficient. Moreover, high ampere, short pulse-off time and low servo-voltage combined with about 250 ?s pulse-on time generate the highest MRR.

Ashikur Rahman Khan, Md; Rahman, M. M.; Kadirgama, K.; Ismail, A. R.

2012-09-01

197

Testing of new banknotes for machines that process currency  

NASA Astrophysics Data System (ADS)

Banknotes are now frequently use din machines. The Federal Reserve Board and the US Department of the Treasury have identified a need to produce notes that are reliably accepted in a variety of machine applications. This paper describes the steps that led to identifying requirements of manufacturers of machines that process banknotes for test notes, and the program developed for the Bureau of Engraving and Printing to address those requirements.

Foster, Eugenie E.

2000-04-01

198

Observable Electron EDM and Leptogenesis  

E-print Network

In the context of the minimal supersymmetric seesaw model, the CP-violating neutrino Yukawa couplings might induce an electron EDM. The same interactions may also be responsible for the generation of the observed baryon asymmetry of the Universe via leptogenesis. We identify in a model-independent way those patterns within the seesaw models which predict an electron EDM at a level probed by planned laboratory experiments and show that negative searches on \\tau-> e \\gamma decay may provide the strongest upper bound on the electron EDM. We also conclude that a possible future detection of the electron EDM is incompatible with thermal leptogenesis, even when flavour effects are accounted for.

F. R. Joaquim; I. Masina; A. Riotto

2007-01-31

199

Influence of the Composition of WC-Based Cermets on Manufacturability by Wire-EDM  

Microsoft Academic Search

Tungsten carbide (WC) based cermets are widely used in applications where the demand for high-performance materials is essential. These materials are machined either by grinding or wire-EDM. In contrast to grinding, wire-EDM can be highly automated and allows the machining of complex shapes. A recent trend in the development of WC-based cermets is grain size refinement and more narrow grain

Bert Lauwers; Weidong Liu; Wesley Eeraerts

2006-01-01

200

Wire-cut electrical discharge machinability of ceramics. Final report  

SciTech Connect

The wire-cut electrical discharge machinability of four ceramics was evaluated. Titanium diboride and silicon carbide workpieces were successfully cut in the monolithic state. Boron carbide could only be cut when a metallic sandwich structure was placed around the workpiece. Silicon nitride could not be successfully cut. Mechanisms of material removal as well as a minimum level of workpiece electrical conductance necessary for EDM are proposed. Characterization of the surface damage resulting from electrical-discharge machining is presented. Recast, partially melted, and heat-affected zones are identified. The effects of parametric processing variations on surface integrity are discussed. Flexure strength and residual stress data are compared for EDM cut and diamond-ground surfaces in titanium diboride. Certain limitations are proposed for the EDM fabrication of ceramic components where surface defects are strength limiting.

Ricci, W.S.; Skeele, H.A.; Blumenthal, W.R.

1987-09-01

201

State machine analysis of sensor data from dynamic processes  

DOEpatents

A state machine model analyzes sensor data from dynamic processes at a facility to identify the actual processes that were performed at the facility during a period of interest for the purpose of remote facility inspection. An inspector can further input the expected operations into the state machine model and compare the expected, or declared, processes to the actual processes to identify undeclared processes at the facility. The state machine analysis enables the generation of knowledge about the state of the facility at all levels, from location of physical objects to complex operational concepts. Therefore, the state machine method and apparatus may benefit any agency or business with sensored facilities that stores or manipulates expensive, dangerous, or controlled materials or information.

Cook, William R.; Brabson, John M.; Deland, Sharon M.

2003-12-23

202

Automatic design of fixtures for machining processes  

Microsoft Academic Search

The function of fixtures is to locate and hold workpieces for machining, assembly, inspection and other operations. The essential criteria in fixture design are accuracy and repeatability of workpiece location, and lack of interference between fixture elements and tools. Other criteria of fixtures may include ease of loading and unloading workpieces, light weight, low cost and rigidity.^ In this study

Yon-Chun Chou

1988-01-01

203

Development of micro-EDM-center with rapidly sharpened electrode  

Microsoft Academic Search

In single discharge machining of a 0.1mm tungsten electrode with 3050A discharge current and several hundreds of microseconds duration, a needle of 2040?m in diameter has been formed instantaneously. The formed needle or thin axis tip radius is less than 100nm. This new phenomenon is applied to making very thin electrodes for micro-EDM or as micro-probes for various on-the-machine measurements.

Hideki Takezawa; Hiroaki Hamamatsu; Naotake Mohri; Nagao Saito

2004-01-01

204

Surface modification using semi-sintered electrodes on electrical discharge machining  

Microsoft Academic Search

This study investigates how machining characteristics and surface modifications affect low-carbon steel (S15C) during electrical\\u000a discharge machining (EDM) processes with semi-sintered electrodes. Among the machining characteristics determined, the material\\u000a removal rate (MRR), surface deposit rate (SDR), and electrode wear rate (EWR) are included. Additionally, exactly how semi-sintered\\u000a electrodes affect the surface modifications is also evaluated by electron probe microanalyzer (EPMA),

Yuan-Feng Chen; Han-Ming Chow; Yan-Cherng Lin; Ching-Tien Lin

2008-01-01

205

Co-option of EDM2 to distinct regulatory modules in Arabidopsis thaliana development  

PubMed Central

Background Strong immunity of plants to pathogenic microorganisms is often mediated by highly specific mechanisms of non-self recognition that are dependent on disease resistance (R) genes. The Arabidopsis thaliana protein EDM2 is required for immunity mediated by the R gene RPP7. EDM2 is nuclear localized and contains typical features of transcriptional and epigenetic regulators. In addition, to its role in immunity, EDM2 plays also a role in promoting floral transition. This developmental function of EDM2, but not its role in RPP7-mediated disease resistance, seems to involve the protein kinase WNK8, which physically interacts with EDM2 in nuclei. Results Here we report that EDM2 affects additional developmental processes which include the formation of leaf pavement cells and leaf expansion as well as the development of morphological features related to vegetative phase change. EDM2 has a promoting effect of each of these processes. While WNK8 seems not to exhibit any vegetative phase change-related function, it has a promoting effect on the development of leaf pavement cells and leaf expansion. Microarray data further support regulatory interactions between WNK8 and EDM2. The fact that the effects of EDM2 and WNK8 on leaf pavement cell formation and leaf expansion are co-directional, while WNK8 counteracts the promoting effect of EDM2 on floral transition, is surprising and suggests that WNK8 can modulate the activity of EDM2. Conclusion We propose that EDM2 has been co-opted to distinct regulatory modules controlling a set of different processes in plant immunity and development. WNK8 appears to modulate some functions of EDM2. PMID:20840782

2010-01-01

206

Process for laser machining and surface treatment  

DOEpatents

An improved method and apparatus increasing the accuracy and reducing the time required to machine materials, surface treat materials, and allow better control of defects such as particulates in pulsed laser deposition. The speed and quality of machining is improved by combining an ultrashort pulsed laser at high average power with a continuous wave laser. The ultrashort pulsed laser provides an initial ultrashort pulse, on the order of several hundred femtoseconds, to stimulate an electron avalanche in the target material. Coincident with the ultrashort pulse or shortly after it, a pulse from a continuous wave laser is applied to the target. The micromachining method and apparatus creates an initial ultrashort laser pulse to ignite the ablation followed by a longer laser pulse to sustain and enlarge on the ablation effect launched in the initial pulse. The pulse pairs are repeated at a high pulse repetition frequency and as often as desired to produce the desired micromachining effect. The micromachining method enables a lower threshold for ablation, provides more deterministic damage, minimizes the heat affected zone, minimizes cracking or melting, and reduces the time involved to create the desired machining effect.

Neil, George R.; Shinn, Michelle D.

2004-10-26

207

Influence of silicon powder-mixed dielectric on conventional electrical discharge machining  

Microsoft Academic Search

Electrical discharge machining (EDM) is a technological process with a large industrial implementation. Its use is particularly intense when very complex shapes on hard materials with a high geometrical and dimensional accuracy are required. However, the technological capability of the process has limited its application when the specification of the part surface quality imposes polished and mirror-like characteristics. The addition

P Peas; E Henriques

2003-01-01

208

Modern Technologies for Processing Wastes from Machining Operations  

Microsoft Academic Search

There are currently many methods available for processing and recycling wastes from machining operations [1]. Although some of them consume large amounts of energy and require special equipment or special processing regimes (remelting, comminution, sintering in heating furnaces, hot and cold pressing), significant amounts of the raw material are also lost in the process. For example, the losses incurred in

V. V. Zharikov

2001-01-01

209

Application of Hollow Sphere Structures and Composites in Processing Machines  

NASA Astrophysics Data System (ADS)

The term processing machines refers to a large variety of machines and equipment for the mass production of consumer goods. Processing machines are often specially tailored according to the particular processing task they have to fulfill, such as pasteurising milk or packing goods. Furthermore the vast majority is characterised by large production outputs, demanding high processing velocities and fast moving parts. A special application is that of the food and drug processing area. Due to high quality standards there are special requirements for material surfaces to be considered if surfaces are in contact with the manufactured product. This chapter deals with the special demands concerning dedicated engineering materials that occur from state of the art processing machines. Specific requirements ranging from high damping abilities for support components to high stiffness and low weight for fast moving tools are presented by means of a general classification of processing machines into four functional areas. Accordingly, the proposed hollow sphere structures and similar material classes are presented and applied on each of these four areas.

Schler, Martin; Mauermann, Marc; Majschak, Jens-Peter

210

Effects of sandblasting and electrical discharge machining on porcelain adherence to cast and machined commercially pure titanium.  

PubMed

The aim of this study was to determine the effect of sandblasting and electrical discharge machining (EDM) on cast and machined titanium surfaces and titanium-porcelain adhesion. Twenty machined titanium specimens were prepared by manufacturer (groups 1 and 2). Thirty specimens were prepared with autopolymerizing acrylic resin. Twenty of these specimens (groups 3 and 4) were cast with commercially pure titanium and the alpha-case layer was removed. For control group (group 5), 10 specimens were cast by using NiCr alloy. Groups 2 and 4 were subjected to EDM while groups 1, 3, and 5 were subjected to sandblasting. Surface examinations were made by using a scanning electron microscope (SEM). A low-fusing porcelain was fused on the titanium surfaces, whereas NiCr specimens were covered using a conventional porcelain. Titanium-porcelain adhesion was characterized by a 3-point bending test. Results were analyzed by Kruskal-Wallis and Mann-Whitney U tests. Metal-porcelain interfaces were characterized by SEM. The bond strength of control group was higher than that of the titanium-porcelain system. There was no significant difference between cast and machined titanium groups (p > 0.05). There was no significant difference between EDM and sandblasting processes (p > 0.05). The use of EDM as surface treatment did not improve titanium-porcelain adhesion compared with sandblasting. PMID:16447164

Inan, Ozgr; Acar, Asli; Halkaci, Seluk

2006-08-01

211

Searching for the electron EDM in a storage ring  

NASA Astrophysics Data System (ADS)

Searches for permanent electric dipole moments (EDM) of fundamental particles have been underway for more than 50 years with null results. Still, such searches are of great interest because EDMs arise from radiative corrections involving processes that violate parity and time-reversal symmetries, and through the CPT theorem, are sensitive to CP-violation. New models of physics beyond the standard model predict new sources of CP-violation leading to dramatically enhanced EDMs possibly within the reach of a new generation of experiments. We describe a new approach to electron EDM searches using molecular ions stored in a tabletop electrostatic storage ring. Molecular ions with long-lived paramagnetic states such as tungsten nitride WN+ can be injected and stored in larger numbers and with longer coherence times than competing experiments, leading to high sensitivity to an electron EDM. Systematic effects mimicking an EDM such as those due to motional magnetic fields and geometric phases are found not to limit the approach in the short term, and sensitivities of ?|de| ? 10-30 ecm/day appear possible under conservative conditions.

Kawall, D.

2011-05-01

212

Soviet Patent Bulletin Processing: A Particular Application of Machine Translation.  

ERIC Educational Resources Information Center

Describes some of the processes involved in the data structure manipulation and machine translation of a specific text form, namely, Soviet patent bulletins. The effort to modify this system in order to do specialized processing and translation is detailed. (Author/SED)

Bostad, Dale A.

1985-01-01

213

Relationships between Gaussian processes, Support Vector machines and Smoothing Splines  

Microsoft Academic Search

Bayesian Gaussian processes and Support Vector machines are pow- erful kernel-based methods to attack the pattern recognition problem. Probably due to the very dieren t philosophies of the elds they have been originally proposed in, techniques for these two models have been developed somewhat in isolation from each other. This tutorial paper reviews relationships between Bayesian Gaussian processes and Support

Matthias Seeger

2000-01-01

214

Gaussian Processes in Machine Learning Carl Edward Rasmussen  

E-print Network

Gaussian Processes in Machine Learning Carl Edward Rasmussen Max Planck Institute for Biological Cybernetics, 72076 T¨ubingen, Germany carl@tuebingen.mpg.de WWW home page: http://www.tuebingen.mpg.de/carl the data can be discarded. #12;68 Carl Edward Rasmussen Definition 1. A Gaussian Process is a collection

Edinburgh, University of

215

Hardware implementation of machine vision systems: image and video processing  

NASA Astrophysics Data System (ADS)

This contribution focuses on different topics covered by the special issue titled `Hardware Implementation of Machine vision Systems' including FPGAs, GPUS, embedded systems, multicore implementations for image analysis such as edge detection, segmentation, pattern recognition and object recognition/interpretation, image enhancement/restoration, image/video compression, image similarity and retrieval, satellite image processing, medical image processing, motion estimation, neuromorphic and bioinspired vision systems, video processing, image formation and physics based vision, 3D processing/coding, scene understanding, and multimedia.

Botella, Guillermo; Garca, Carlos; Meyer-Bse, Uwe

2013-12-01

216

Optimization of Abrasive Powder Mixed EDM of Aluminum Matrix Composites with Multiple Responses Using Gray Relational Analysis  

NASA Astrophysics Data System (ADS)

Abrasive powder-mixed electrical discharge machining (APM-EDM), a hybrid manufacturing process involving the use of a dielectric fluid mixed with abrasive powder, combines the benefits of mechanical and thermal interactions. The aim of this article is to use a new approach of performance evaluation, gray relational analysis (GRA), to evaluate the effectiveness of optimizing multiple performance characteristics of APM-EDM of 6061Al/Al2O3p/20p aluminum matrix composites (AMCs). The considered process parameter includes the seven control factors namely pulse current (A), pulse ON time (?s), duty cycle (%), gap voltage (V), time interval of tool lift (s), abrasive powder concentration (g/L), abrasive particle size (?m), and a noise factor, aspect ratio (shape of tool electrode). The combination of L18 (21 37) orthogonal array design of experiment with GRA enables to determine the optimal parameters for multiple responses. GRA is used to obtain a single performance index, gray relational grade through gray relational coefficient to optimize the APM-EDM process with lower tool wear rate, surface roughness, and higher material removal rate. In addition, analysis of variance (ANOVA) for the GRC is also utilized.

Singh, S.; Yeh, M. F.

2012-04-01

217

NC verification for wire-EDM using an R-map  

Microsoft Academic Search

Due to the high complexity and the low speed of the wire-EDM process, it is important to recognize all the possible errors before starting the process. The unproductive and time consuming test runs of wire-EDM NC programs in the real production environment can be avoided by computer graphic simulation. In this paper, a data structure and an algorithm are introduced

Yang Minyang; Lee Eungki

1996-01-01

218

Learning Processes in Man, Machine and Society  

ERIC Educational Resources Information Center

Deciphering the learning mechanism which exists in man remains to be solved. This article examines the learning process with respect to association and cybernetics. It is recommended that research should focus on the transdisciplinary processes of learning which could become the next key concept in the science of man. (Author/MA)

Malita, Mircea

1977-01-01

219

CAD tool for the design and manufacturing of freeform micro-EDM electrodes  

Microsoft Academic Search

It is known the micro-EDM is a proper and flexible technology to machine freeform three-dimensional microstructures. Unfortunately, its capabilities are underestimated by the ruling microsystem designers due to the lack of widespread modeling and simulation tools. In this paper the strength of micro-EDM is reflected onto a solid modeling design environment, in which all designs are parametric and feature based.

Wim Meeusen; Dominiek Reynaerts; Hendrik Van Brussel

2002-01-01

220

Improvement of surface finish on SKD steel using electro-discharge machining with aluminum and surfactant added dielectric  

Microsoft Academic Search

Electrical discharge machining (EDM) process is widely used to process hard materials in the industry. Electrical discharge distribution effects can be achieved by the addition of Al powder in the dielectric. A fine surface roughness value of the workpiece is thus obtained. However, the electrostatic force among fine Al particles is found to agglomerate the Al powders in the dielectric.

Kun Ling Wu; Biing Hwa Yan; Fuang Yuan Huang; Shin Chang Chen

2005-01-01

221

Controlled English to facilitate human/machine analytical processing  

NASA Astrophysics Data System (ADS)

Controlled English is a human-readable information representation format that is implemented using a restricted subset of the English language, but which is unambiguous and directly accessible by simple machine processes. We have been researching the capabilities of CE in a number of contexts, and exploring the degree to which a flexible and more human-friendly information representation format could aid the intelligence analyst in a multi-agent collaborative operational environment; especially in cases where the agents are a mixture of other human users and machine processes aimed at assisting the human users. CE itself is built upon a formal logic basis, but allows users to easily specify models for a domain of interest in a human-friendly language. In our research we have been developing an experimental component known as the "CE Store" in which CE information can be quickly and flexibly processed and shared between human and machine agents. The CE Store environment contains a number of specialized machine agents for common processing tasks and also supports execution of logical inference rules that can be defined in the same CE language. This paper outlines the basic architecture of this approach, discusses some of the example machine agents that have been developed, and provides some typical examples of the CE language and the way in which it has been used to support complex analytical tasks on synthetic data sources. We highlight the fusion of human and machine processing supported through the use of the CE language and CE Store environment, and show this environment with examples of highly dynamic extensions to the model(s) and integration between different user-defined models in a collaborative setting.

Braines, Dave; Mott, David; Laws, Simon; de Mel, Geeth; Pham, Tien

2013-06-01

222

Parametric optimization of powder mixed electrical discharge machining by response surface methodology  

Microsoft Academic Search

In the present work, a study has been made to optimize the process parameters of powder mixed electrical discharge machining (PMEDM). Response surface methodology has been used to plan and analyze the experiments. Pulse on time, duty cycle, peak current and concentration of the silicon powder added into the dielectric fluid of EDM were chosen as variables to study the

H. K. Kansal; Sehijpal Singh; P. Kumar

2005-01-01

223

Accretion of titanium carbide by electrical discharge machining with powder suspended in working fluid  

Microsoft Academic Search

A surface modification method by electrical discharge machining (EDM) with a green compact electrode has been studied to make thick TiC or WC layer. Titanium alloy powder or tungsten powder is supplied from the green compact electrode and adheres on a workpiece by the heat caused by discharge. To avoid the production process of the green compact electrode, a surface

Katsushi Furutania; Akinori Saneto; Hideki Takezawa; Naotake Mohri; Hidetaka Miyake

2001-01-01

224

A thermo-electric model of material removal during electric discharge machining  

Microsoft Academic Search

In Electro Discharge Machining (EDM), melting is the main process for metal removal. However, for short pulses (discharge duration <5?s), melting does not account for the results as shown by the experiments reported. For short pulses, metal does not get enough time to get adequately heated and almost no melting takes place. The electrostatic force acting on the surface is

Ajit Singh; Amitabha Ghosh

1999-01-01

225

Mathematical modelling for electric discharge machining of aluminiumsilicon carbide particulate composites  

Microsoft Academic Search

In this paper an attempt has been made to develop mathematical models for optimizing electric discharge machining (EDM) characteristics such as the metal removal rate (MRR), the tool wear rate (TWR) and the surface roughness (CLA value). The process parameters taken in to consideration were the current (I), the pulse duration (T) and the percent volume fraction of SiC (25

R Karthikeyan; P. R Lakshmi Narayanan; R. S Naagarazan

1999-01-01

226

Design and Implementation of Process Migrating among Multiple Virtual Machines  

Microsoft Academic Search

\\u000a Process migrating technology usually is used to solve the problems like user process death, system crash or lower executing\\u000a efficiency because of the load unbalancing among the multi-processors. Virtual machine can supply system level backup and\\u000a migration. But it is too much overhead sometimes. In this paper, a process migration technology on program level is put forward\\u000a and a demo

Si Shen; Zexian Zhang; Shuangxi Yang; Ruilin Guo; Murong Jiang

2011-01-01

227

Micro and nano-crystalline CVD diamond coated tools in the turning of EDM graphite  

Microsoft Academic Search

Electrical discharge machining is a widely used technique, namely in metal mould shaping. High quality EDM graphite is the foremost choice as electrode material but the random oriented graphite aggregates cause an abrasive action over the tools used in its machining. Wear-resistant diamond tools were then chosen as an adequate option to guarantee tight tolerances and good surface finishing. In

F. A. Almeida; J. Sacramento; F. J. Oliveira; R. F. Silva

2008-01-01

228

Computational fluid dynamics analysis of working fluid flow and debris movement in wire EDMed kerf  

Microsoft Academic Search

In wire EDM, better exclusion of debris from the machined kerf is very important to obtain a stable machining performance. The purpose of this study is to investigate the fluid flow in the kerf and better jet flushing conditions of working fluid from the nozzles. The flow field and the debris motion in the kerf were analyzed by computational fluid

A. Okada; Y. Uno; S. Onoda; S. Habib

2009-01-01

229

The skin-effect in ferromagnetic electrodes for wire-EDM  

Microsoft Academic Search

In wire electrical discharge machining (wire-EDM) material is removed by the thermal energy of an electric spark that has been initiated between two electrodes (the wire and the workpiece), submerged in demineralised water. The use of high frequency current pulses for sparking leads to excellent machining performance, in terms of the work piece roughness, the material integrity of the cut

B. Schacht; J.-P. Kruth; B. Lauwers; P. Vanherck

2004-01-01

230

Modeling of wire-cut EDM by neural network  

NASA Astrophysics Data System (ADS)

Wire-cut EDM is a highly complex process, which is characterized by non-linear behavior. Due to very large number of input parameters, a Neural Network Approach is followed in this paper to model this process. A large number of experiments have been carried out to train the network. The model is also tested using additional experimental data. It is found that neural network models of wire-cut EDM process provide results with required accuracy. The important input parameters have been identified and reported in this paper.

Shunmugam, M. S.; Kumar, S. S.; Kaul, I. K.

1999-08-01

231

Technology and Signal Processing for Brain-Machine Interfaces  

Microsoft Academic Search

Neural interfaces hold the promise to become one of the great technological advancements of the 21st century because they can provide new means of communication by directly accessing and interpreting brain intentional states. This article presents a set of grand challenges for brain-machine interfaces (BMI) and investigates recent advances in neurotechnology and signal processing methods to overcome them.

Justin C. Sanchez; Jose C. Principe; Toshikazu Nishida; Rizwan Bashirullah; John Harris; Jose Fortes

2008-01-01

232

Semantic Processing Performance of Internet Machine Translation Systems.  

ERIC Educational Resources Information Center

Discusses the performance of automatic direct machine translation systems available through the Internet and examines semantic processing errors that result in confusion when the intended meaning of sentences is not correctly translated. Suggests the need for Web-based translation systems that have an explicit cross-linguistic representation of

Watters, Paul A.; Patel, Malti

1999-01-01

233

Process Damping and Cutting Tool Geometry in Machining  

NASA Astrophysics Data System (ADS)

Regenerative vibration, or chatter, limits the performance of machining processes. Consequences of chatter include tool wear and poor machined surface finish. Process damping by tool-workpiece contact can reduce chatter effects and improve productivity. Process damping occurs when the flank (also known as the relief face) of the cutting tool makes contact with waves on the workpiece surface, created by chatter motion. Tool edge features can act to increase the damping effect. This paper examines how a tool's edge condition combines with the relief angle to affect process damping. An analytical model of cutting with chatter leads to a two-section curve describing how process damped vibration amplitude changes with surface speed for radiussed tools. The tool edge dominates the process damping effect at the lowest surface speeds, with the flank dominating at higher speeds. A similar curve is then proposed regarding tools with worn edges. Experimental data supports the notion of the two-section curve. A rule of thumb is proposed which could be useful to machine operators, regarding tool wear and process damping. The question is addressed, should a tool of a given geometry, used for a given application, be considered as sharp, radiussed or worn regarding process damping.

Taylor, C. M.; Sims, N. D.; Turner, S.

2011-12-01

234

Characteristic Cutting Signals for Machined Surface Condition Monitoring in Micro milling Processes  

NASA Astrophysics Data System (ADS)

The demands of mechanical precision micro machining technology have increased due to the need for micro scale precision shapes and parts in biotechnology, optics, and machinery. In the micro-machining process, the machining parameters must be controlled in order to improve the precision and quality of machined parts. Improvements must be made in exclusive precision machining and extensive study of machining technology must be conducted in order to overcome current challenges in the micro machining process. This paper investigates the correlation between the machined surface condition and acoustic emission(AE) signals characterized according to the cutting conditions in the miro-machining process. Micro end mills (200 ?m diameter) and an air turbine spindle (120,000rpm) were used machine aluminum 6061-T6. The characteristics of the AE parameters were extracted in order to monitor the condition of the machined surface texture in micro milling process.

Jang, Su-Hoon; Jang, Ik-Soo; Kim, Jeong-Suk; Choi, Tae-Ku; Gu, Min-Su

2011-01-01

235

Surface treatment by electric discharge machining of Ti-6Al-4V alloy for potential application in orthopaedics.  

PubMed

This study investigated the properties of Ti-6Al-4V alloy after surface treatment by the electric discharge machining (EDM) process. The EDM process with high peak currents proved to induce surface macro-roughness and to cause chemical changes to the surface. Evaluations were made of the mechanical properties by means of tensile tests, and of surface roughness for different peak currents of the EDM process. The EDM process with peak current of 29 A was found to induce sufficient surface roughness, and to have a low adverse effect on tensile properties. The chemical changes were studied by scanning electron microscopy equipped with an energy dispersive X-ray analyser (EDX). The surface of the benchmark samples was obtained by plasma-spraying a titanium dioxide coating. An investigation of the biocompatibility of the surface-treated Ti-6Al-4V samples in cultures of human osteoblast-like MG 63 cells revealed that the samples modified by EDM provided better substrates for the adhesion, growth and viability of MG 63 cells than the TiO2 coated surface. Thus, EDM treatment can be considered as a promising surface modification to orthopaedic implants, in which good integration with the surrounding bone tissue is required. PMID:22340689

Harcuba, Petr; Ba?kov, Lucie; Strsk, Josef; Ba?kov, Markta; Novotn, Katarna; Jane?ek, Milo

2012-03-01

236

Influence of kerosene and distilled water as dielectrics on the electric discharge machining characteristics of Ti6A14V  

Microsoft Academic Search

In electrical discharge machining (EDM), a process utilizing the removal phenomenon of electrical discharge in dielectric, the working fluid plays an important role affecting the material removal rate and the properties of the machined surface. In this paper the machining characteristics of Ti6A14V were investigated with kerosene and distilled water as the dielectrics. The results show that the material removal

S. L. Chen; B. H. Yan; F. Y. Huang

1999-01-01

237

Advanced Cold Molecule Electron EDM  

E-print Network

Measurement of a non-zero electric dipole moment (EDM) of the electron within a few orders of magnitude of the current best limit of |d_e| electron EDM by performing a precision measurement of electron spin precession in the metastable H state of thorium monoxide (ThO) using a slow, cryogenic beam. We discuss the current status of the experiment. Based on a data set acquired from 14 hours of running time over a period of 2 days, we have achieved a 1-sigma statistical uncertainty of 1 e -28 e cm/T^(1/2), where T is the running time in days.

Campbell, Wesley C; DeMille, David; Doyle, John M; Gabrielse, Gerald; Gurevich, Yulia V; Hess, Paul W; Hutzler, Nicholas R; Kirilov, Emil; OLeary, Brendon; Petrik, Elizabeth S; Spaun, Ben; Vutha, Amar C

2013-01-01

238

MATERIAL PROCESSING FOR SELF-ASSEMBLING MACHINE SYSTEMS  

SciTech Connect

We are developing an important aspect of a new technology based on self-reproducing machine systems. Such systems could overcome resource limitations and control the deleterious side effects of human activities on the environment. Machine systems capable of building themselves promise an increase in industrial productivity as dramatic as that of the industrial revolution. To operate successfully, such systems must procure necessary raw materials from their surroundings. Therefore, next to automation, most critical for this new technology is the ability to extract important chemicals from readily available soils. In contrast to conventional metallurgical practice, these extraction processes cannot make substantial use of rare elements. We have designed a thermodynamically viable process and experimentally demonstrated most steps that differ from common practice. To this end we had to develop a small, disposable vacuum furnace system. Our work points to a viable extraction process.

K. LACKNER; D. BUTT; C. WENDT

1999-06-01

239

Simulation of Fatigue Crack Initiation at Corrosion Pits With EDM Notches  

NASA Technical Reports Server (NTRS)

Uniaxial fatigue tests were conducted to compare the fatigue life of laboratory produced corrosion pits, similar to those observed in the shuttle main landing gear wheel bolt-hole, and an electro-discharged-machined (EDM) flaw. EDM Jaws are used to simulate corrosion pits during shuttle wheel (dynamometer) testing. The aluminum alloy, (AA 7050) laboratory fatigue tests were conducted to simulate the local stress level contained in the wheel bolt-hole. Under this high local stress condition, the EDM notch produced a fatigue life similar to test specimens containing corrosion pits of similar size. Based on the laboratory fatigue test results, the EDM Jaw (semi-circular disc shaped) produces a local stress state similar to corrosion pits and can be used to simulate a corrosion pit during the shuttle wheel dynamometer tests.

Smith, Stephen W.; Newman, John A.; Piascik, Robert S.

2003-01-01

240

Evaluation of Process Performance for Sustainable Hard Machining  

NASA Astrophysics Data System (ADS)

This paper aims to evaluate the sustainability performance of machining operation of through-hardening steel, AISI 52100, taking into account the impact of the material removal process in its various aspects. Experiments were performed for dry and cryogenic cutting conditions using chamfered cubic boron nitride (CBN) tool inserts at varying cutting conditions (cutting speed and feed rate). Cutting forces, mechanical power, tool wear, white layer thickness, surface roughness and residual stresses were investigated in order to evaluate the effects of extreme in-process cooling on the machined surface. The results indicate that cryogenic cooling has the potential to be used for surface integrity enhancement for improved product life and more sustainable functional performance.

Rotella, Giovanna; Umbrello, Domenico; , Oscar W. Dillon, Jr.; Jawahir, I. S.

241

Progress towards an electron EDM search using hafnium fluoride ions  

NASA Astrophysics Data System (ADS)

Trapped molecular ions provide large effective electric fields and long electron spin coherence times for the search for an electron electric dipole moment (eEDM). In particular, the ^3?1 state of HfF^+ has been proposed as a candidate for the eEDM search. To create HfF^+, we optically excite a supersonic beam of neutral HfF with two photons to an autoionizing state, and then perform laser-induced fluorescence to detect the state of the resultant HfF^+ ions. We report on our efforts to understand the autoionization process for efficient state preparation of HfF^+ ions, and on our general progress towards an eEDM measurement. This work is funded by the US National Science Foundation.

Loh, Huanqian; Grau, Matt; Yahn, Tyler; Field, Robert; Cornell, Eric

2011-06-01

242

Edme Mariotte and Newton's Cradle  

ERIC Educational Resources Information Center

The first recorded experiments describing the phenomena made popular by Newton's cradle appear to be those conducted by Edme Mariotte around 1670. He was quoted in Newton's "Principia," along with Wren, Wallis, and Huygens, as having conducted pioneering experiments on the collisions of pendulum balls. Each of these authors concluded that momentum

Cross, Rod

2012-01-01

243

Optimization of correlated multiple responses of ultrasonic machining (USM) process  

Microsoft Academic Search

Ultrasonic machining (USM) process has several important performance measures (responses), some of which are correlated. For\\u000a example, material removal rate and tool wear rate are highly correlated. Although in the recent past several methods have\\u000a been proposed in the literature to resolve the multi-response optimization problems, only a few of them take care of the possible\\u000a correlation between the responses.

Susanta Kumar Gauri; Rina Chakravorty; Shankar Chakraborty

2011-01-01

244

Artificial neural networks for machining processes surface roughness modeling  

Microsoft Academic Search

In recent years, several papers on machining processes have focused on the use of artificial neural networks for modeling\\u000a surface roughness. Even in such a specific niche of engineering literature, the papers differ considerably in terms of how\\u000a they define network architectures and validate results, as well as in their training algorithms, error measures, and the like.\\u000a Furthermore, a perusal

Fabricio J. Pontes; Joo R. Ferreira; Messias B. Silva; Anderson P. Paiva; Pedro Paulo Balestrassi

2010-01-01

245

UNH Jerard/Fussell 1 Project Summary -Dynamic Evaluation of Machine Tool Process Capability  

E-print Network

UNH ­ Jerard/Fussell 1 Project Summary - Dynamic Evaluation of Machine Tool Process Capability with cutting tools, machining strategies, age and environment. This lack of a reliable quality measure impacts operations. Cp for a machine tool is currently ill-defined, since machine tool builders only provide a static

New Hampshire, University of

246

Statistical characteristic and parameter characterization of 3D surface micro-topography on micro-EDM  

Microsoft Academic Search

The characteristic of three-dimensional (3D) surface micro-topography of micro-EDM plays an important role on the component function properties. In this paper, two types of 3D surface micro-topography, which machined by micro-electrical discharge machining forming (micro-EDMF) and micro-wire electrical discharge machining (micro-WEDM), have been measured by the atomic force microscope (AFM) instrument after the surface data have been reshaped and denoised

Haijuan Ding; Libin Guo; Hai Cui

2009-01-01

247

Process Monitoring Evaluation and Implementation for the Wood Abrasive Machining Process  

PubMed Central

Wood processing industries have continuously developed and improved technologies and processes to transform wood to obtain better final product quality and thus increase profits. Abrasive machining is one of the most important of these processes and therefore merits special attention and study. The objective of this work was to evaluate and demonstrate a process monitoring system for use in the abrasive machining of wood and wood based products. The system developed increases the life of the belt by detecting (using process monitoring sensors) and removing (by cleaning) the abrasive loading during the machining process. This study focused on abrasive belt machining processes and included substantial background work, which provided a solid base for understanding the behavior of the abrasive, and the different ways that the abrasive machining process can be monitored. In addition, the background research showed that abrasive belts can effectively be cleaned by the appropriate cleaning technique. The process monitoring system developed included acoustic emission sensors which tended to be sensitive to belt wear, as well as platen vibration, but not loading, and optical sensors which were sensitive to abrasive loading. PMID:22163477

Saloni, Daniel E.; Lemaster, Richard L.; Jackson, Steven D.

2010-01-01

248

Process monitoring evaluation and implementation for the wood abrasive machining process.  

PubMed

Wood processing industries have continuously developed and improved technologies and processes to transform wood to obtain better final product quality and thus increase profits. Abrasive machining is one of the most important of these processes and therefore merits special attention and study. The objective of this work was to evaluate and demonstrate a process monitoring system for use in the abrasive machining of wood and wood based products. The system developed increases the life of the belt by detecting (using process monitoring sensors) and removing (by cleaning) the abrasive loading during the machining process. This study focused on abrasive belt machining processes and included substantial background work, which provided a solid base for understanding the behavior of the abrasive, and the different ways that the abrasive machining process can be monitored. In addition, the background research showed that abrasive belts can effectively be cleaned by the appropriate cleaning technique. The process monitoring system developed included acoustic emission sensors which tended to be sensitive to belt wear, as well as platen vibration, but not loading, and optical sensors which were sensitive to abrasive loading. PMID:22163477

Saloni, Daniel E; Lemaster, Richard L; Jackson, Steven D

2010-01-01

249

Galaxy Image Processing and Morphological Classification Using Machine Learning  

NASA Astrophysics Data System (ADS)

This work uses data from the Sloan Digital Sky Survey (SDSS) and the Galaxy Zoo Project for classification of galaxy morphologies via machine learning. SDSS imaging data together with reliable human classifications from Galaxy Zoo provide the training set and test set for the machine learning architectures. Classification is performed with hand-picked, pre-computed features from SDSS as well as with the raw imaging data from SDSS that was available to humans in the Galaxy Zoo project. With the hand-picked features and a logistic regression classifier, 95.21% classification accuracy and an area under the ROC curve of 0.986 are attained. In the case of the raw imaging data, the images are first processed to remove background noise, image artifacts, and celestial objects other than the galaxy of interest. They are then rotated onto their principle axis of variance to guarantee rotational invariance. The processed images are used to compute color information, up to 4^th order central normalized moments, and radial intensity profiles. These features are used to train a support vector machine with a 3^rd degree polynomial kernel, which achieves a classification accuracy of 95.89% with an ROC area of 0.943.

Kates-Harbeck, Julian

2012-03-01

250

Effect of electrode material on electrical discharge machining of alumina  

Microsoft Academic Search

Technologies for machining advanced insulating ceramics are demanded in many industrial fields. Recently, several insulating ceramics, such as Si3N4, SiC and ZrO2, have been successfully machined by electrical discharge machining (EDM). As unstable discharges occur during the machining of Al2O3 ceramics, inferior machining properties have been obtained. The formation mechanism of the electrical conductive layer on the EDMed surface is

A. Muttamara; Y. Fukuzawa; N. Mohri; T. Tani

2009-01-01

251

Study of the Diffusion of Carbon, Its Sources, and Effect on Finishing Micro-EDM Performance of Cemented Carbide  

NASA Astrophysics Data System (ADS)

Apart from the necessity of surface modification based on different applications, in most of the cases, diffusion of carbon or foreign particles on the workpiece surface during micro-electrodischarge machining (micro-EDM) is avoidable, especially in finishing micro-EDM. This study aims to investigate different sources of materials that migrate to the machined surface during fine-finishing of micro-EDM of cemented tungsten carbide (WC-Co). The machined surfaces have been examined under scanning electron microscope and energy dispersive x-ray to investigate the changes in chemical composition. It has been observed that during finishing of micro-EDM, the major source of materials' transfer to both the workpiece and electrode is the diffusion of carbon that comes from the decomposition of the hydrocarbon dielectric. In addition, materials from both workpiece and electrode transfer to each other based on machining conditions and discharge energy. The migration occurs more frequently at lower gap voltages during die-sinking with micro-EDM because of low spark gap and stationary tool electrode. Milling micro-EDM results in lower amount of carbon migration and fewer surface defects that improve the overall surface finish significantly.

Jahan, M. P.; Rahman, M.; Wong, Y. S.

2012-08-01

252

The fabrication of a micro-spiral structure using EDM deposition in the air  

NASA Astrophysics Data System (ADS)

A novel micromachining method to deposit a micro-3D spiral structure in air using electrical discharge machining (EDM) with a brass electrode was presented. During the deposition process, a 3D spiral structure is obtained only by the feed of the z-axis in the vertical direction. Furthermore, the obtained structure can be formed and repeated stably even in the upside-down direction under a gravity environment. It is seen that the material components of a micro-spiral structure are almost the same as those of an electrode by the energy spectrum analysis of a micro-spiral structure. According to scanning electron microscope photographs, the micro-spiral appears to feature a layered material organism structure and has compact bonding with the body material. In order to understand the forming mechanism of this kind of micro-spiral structure, simulation analysis is conducted. The track of the deposition particles can be obtained by simulation, which determines the shape of the deposited structure. According to the simulation results, the track of the deposition particles is consistent with that of EDM experiments. It is further found that the distribution of the electromagnetic field in a discharge channel has an important influence on the deposited structure and the track of the deposition particles.

Chi, Guanxin; Wang, Zhenlong; Xiao, K.; Cui, Jingzhi; Jin, Baidong

2008-03-01

253

Performance of Process Damping in Machining Titanium Alloys at Low Cutting Speed with Different Helix Tools  

NASA Astrophysics Data System (ADS)

Titanium is a strong, lustrous, corrosion-resistant and transition metal with a silver color to produce strong lightweight alloys for industrial process, automotive, medical instruments and other applications. However, it is very difficult to machine the titanium due to its poor machinability. When machining titanium alloys with the conventional tools, the wear rate of the tool is rapidly accelerate and it is generally difficult to achieve at high cutting speed. In order to get better understanding of machining titanium alloy, the interaction between machining structural system and the cutting process which result in machining instability will be studied. Process damping is a useful phenomenon that can be exploited to improve the limited productivity of low speed machining. In this study, experiments are performed to evaluate the performance of process damping of milling under different tool helix geometries. The results showed that the helix of 42 angle is significantly increase process damping performance in machining titanium alloy.

Shaharun, M. A.; Yusoff, A. R.; Reza, M. S.; Jalal, K. A.

2012-09-01

254

Effect of near-surface residual stress and microstructure modification from machining on the fatigue endurance of a tool steel  

Microsoft Academic Search

This study concerns the effect of machining on the fatigue life of an EN X155CrMoV12 tool steel (SAE J438b), with regard to\\u000a the generation of near-surface residual stress and microstructural modification of the machined surface. Two possible methods\\u000a for machining tool steels were compared: electro-discharge machining (EDM), a high energy density process, and milling, a\\u000a more conventional cutting process. Particular

F. Ghanem; H. Sidhom; C. Braham; M. E. Fitzpatrick

2002-01-01

255

Advanced cold molecule electron EDM  

NASA Astrophysics Data System (ADS)

Measurement of a non-zero electric dipole moment (EDM) of the electron within a few orders of magnitude of the current best limit of |de| < 1.05 10-27 e?cm [1] would be an indication of physics beyond the Standard Model. The ACME Collaboration is searching for an electron EDM by performing a precision measurement of electron spin precession in the metastable H3?1 state of thorium monoxide (ThO) using a slow, cryogenic beam. We discuss the current status of the experiment. Based on a data set acquired from 14 hours of running time over a period of 2 days, we have achieved a 1-sigma statistical uncertainty of ?de = 1 10-28 e?cm/?T, where T is the running time in days.

Campbell, Wesley C.; Chan, Cheong; DeMille, David; Doyle, John M.; Gabrielse, Gerald; Gurevich, Yulia V.; Hess, Paul W.; Hutzler, Nicholas R.; Kirilov, Emil; O'Leary, Brendon; Petrik, Elizabeth S.; Spaun, Ben; Vutha, Amar C.

2013-08-01

256

Observable Electron Edm and Leptogenesis  

Microsoft Academic Search

In the context of the minimal supersymmetric seesaw model, the CP-violating neutrino Yukawa couplings might induce an electron electric dipole moment (EDM). The same interactions may also be responsible for the generation of the observed baryon asymmetry of the universe via leptogenesis. In the framework of mSUGRA, we identify in a model-independent way those patterns within the seesaw models which

F. R. Joaquim; I. Masina; Antonio Riotto

2007-01-01

257

Parametric optimization and surface characterization of wire electrical discharge machining process  

Microsoft Academic Search

Wire electrical discharge machining (WEDM) technology has been widely used in conductive material machining. The WEDM process, which is a combination of electrodynamic, electromagnetic, thermaldynamic, and hydrodynamic actions, exhibits a complex and stochastic nature. Its performance, in terms of surface finish and machining productivity, is affected by many factors. This paper presents an attempt at optimization of the process parametric

T. A. Spedding; Z. Q. Wang

1997-01-01

258

Optimization of the electrical discharge machining process based on the Taguchi method with fuzzy logics  

Microsoft Academic Search

In this paper, the application of the Taguchi method with fuzzy logic for optimizing the electrical discharge machining process with multiple performance characteristics has been reported. A multi-response performance index is used to solve the electrical discharge machining process with multiple performance characteristics. The machining parameters (the workpiece polarity, pulse-on time, duty factor, open discharge voltage, discharge current and dielectric

J. L. Lin; K. S. Wang; B. H. Yan; Y. S. Tarng

2000-01-01

259

Automatic signal processing of front monitor radar for tunneling machines  

SciTech Connect

It is planned to install a front monitoring impulse radar on the surface of the rotating drill of tunneling machines in order to detect obstacles such as casing pipes of vertical borings. The conventional aperture synthesis technique can no more be applied to such cases because the radar image of a pipe dies not constituent a hyperbola as is the case for linear scanning radars. The authors have developed a special purpose signal processing algorithm with the aid of the discrete model fitting method, which can be used for any pattern of scanning. The details of the algorithm are presented together with the results of numerical simulations and test site experiments.

Sato, Toru [Kyoto Univ. (Japan). Dept. of Electronics and Communication] [Kyoto Univ. (Japan). Dept. of Electronics and Communication; Takeda, Kenya [NTT Co. Ltd., Chiba (Japan)] [NTT Co. Ltd., Chiba (Japan); Nagamatsu, Takashi [Mitsubishi Heavy Industries, Ltd., Tokyo (Japan)] [Mitsubishi Heavy Industries, Ltd., Tokyo (Japan); Wakayama, Toshio [Mitsubishi Electric Corp., Kamakura, Kanagawa (Japan)] [Mitsubishi Electric Corp., Kamakura, Kanagawa (Japan); Kimura, Iwane [Osaka Inst. of Tech., Hirakata, Osaka (Japan)] [Osaka Inst. of Tech., Hirakata, Osaka (Japan); Shinbo, Tetsuya [Komatsu Co. Ltd., Kanagawa (Japan)] [Komatsu Co. Ltd., Kanagawa (Japan)

1997-03-01

260

Statistical process control (SPC) for coordinate measurement machines  

SciTech Connect

The application of process capability analysis, using designed experiments, and gage capability studies as they apply to coordinate measurement machine (CMM) uncertainty analysis and control will be demonstrated. The use of control standards in designed experiments, and the use of range charts and moving range charts to separate measurement error into it's discrete components will be discussed. The method used to monitor and analyze the components of repeatability and reproducibility will be presented with specific emphasis on how to use control charts to determine and monitor CMM performance and capability, and stay within your uncertainty assumptions.

Escher, R.N.

2000-01-04

261

A fuzzy pulse discriminating system for electrical discharge machining  

Microsoft Academic Search

In this paper, the use of fuzzy set theory to construct a new pulse discriminator in electrical discharge machining (EDM) is reported. The classification of various discharge pulses in EDM is based on the features of the measured gap voltage and gap current. To obtain optimal classification performance, a machine learning method based on a simulated annealing algorithm is adopted

Y. S. Tarng; C. M. Tseng; L. K. Chung

1997-01-01

262

Neutron-electron EDM correlations in supersymmetry and prospects for EDM searches  

Microsoft Academic Search

Motivated by recent progress in experimental techniques of electric dipole moment (EDM) measurements, we study correlations between the neutron and electron EDMs in common supersymmetric models. These include minimal supergravity (mSUGRA) with small CP phases, mSUGRA with a heavy SUSY spectrum, the decoupling scenario and split SUSY. In most cases, the electron and neutron EDMs are found to be observable

Steven A. Abel; Oleg Lebedev

2006-01-01

263

CNC electrical discharge machining centers  

SciTech Connect

Computer numerical control (CNC) electrical discharge machining (EDM) centers were investigated to evaluate the application and cost effectiveness of establishing this capability at Allied-Signal Inc., Kansas City Division (KCD). In line with this investigation, metal samples were designed, prepared, and machined on an existing 15-year-old EDM machine and on two current technology CNC EDM machining centers at outside vendors. The results were recorded and evaluated. The study revealed that CNC EDM centers are a capability that should be established at KCD. From the information gained, a machine specification was written and a shop was purchased and installed in the Engineering Shop. The older machine was exchanged for a new model. Additional machines were installed in the Tool Design and Fabrication and Precision Microfinishing departments. The Engineering Shop machine will be principally used for the following purposes: producing deep cavities in small corner radii, machining simulated casting models, machining difficult-to-machine materials, and polishing difficult-to-hand polish mold cavities. 2 refs., 18 figs., 3 tabs.

Jaggars, S.R.

1991-10-01

264

Six-Axis Electrical-Discharge Machine  

NASA Technical Reports Server (NTRS)

Electrical discharge machine (EDM) of unusual versitility made by conversion of radial drill. Drilling head is replaced by ram that holds and positions electrode. Tank and recirculation system for coolant are added. EDM has six independent motions and drastically reduced cost of manufacturing. New applications are constantly being found.

Werner, A. R.

1983-01-01

265

Electric dipole moments (EDM) of ionic atoms  

SciTech Connect

Recent investigations show that the second-order perturbation calculations of electric dipole moments (EDM) from the finite nuclear size as well as the relativistic effects are all canceled out by the third-order perturbation effects and that this is due to electron screening. To derive the nucleon EDM from the nucleus, we propose to measure the EDM of an ionic system. In this case, it is shown that the nucleon EDM can survive by the reduction factor of 1/Z for the ionic system with one electron stripped off.

Oshima, Sachiko [Department of Physics, Faculty of Science and Technology, Nihon University, Tokyo (Japan)

2010-03-15

266

Three-dimensional Composite Lattice Structures Fabricated by Electrical Discharge Machining  

E-print Network

Three-dimensional Composite Lattice Structures Fabricated by Electrical Discharge Machining J construction by means of electrical discharge machining (EDM). First, flat- top corrugated carbon fiber . Sandwich panel . Mechanical properties . Electrical Discharge Machining Introduction Sandwich panels

Vaziri, Ashkan

267

Fabrication of high aspect ratio microstructure arrays by micro reverse wire-EDM  

Microsoft Academic Search

In this paper, a machining technique to fabricate high aspect ratio microstructure arrays of a total volume less than 1 mm3 is developed. A method for determining the appropriate tension of the micro brass wire of the micro wire-EDM mechanism designed in our previous study is proposed, and a design for suppressing the vibration of the wire is implemented. In

Yunn-Shiuan Liao; Shun-Tong Chen; Chang-Sheng Lin; Tzung-Jen Chuang

2005-01-01

268

Parallel astronomical data processing with Python: Recipes for multicore machines  

NASA Astrophysics Data System (ADS)

High performance computing has been used in various fields of astrophysical research. But most of it is implemented on massively parallel systems (supercomputers) or graphical processing unit clusters. With the advent of multicore processors in the last decade, many serial software codes have been re-implemented in parallel mode to utilize the full potential of these processors. In this paper, we propose parallel processing recipes for multicore machines for astronomical data processing. The target audience is astronomers who use Python as their preferred scripting language and who may be using PyRAF/IRAF for data processing. Three problems of varied complexity were benchmarked on three different types of multicore processors to demonstrate the benefits, in terms of execution time, of parallelizing data processing tasks. The native multiprocessing module available in Python makes it a relatively trivial task to implement the parallel code. We have also compared the three multiprocessing approaches-Pool/Map, Process/Queue and Parallel Python. Our test codes are freely available and can be downloaded from our website.

Singh, Navtej; Browne, Lisa-Marie; Butler, Ray

2013-08-01

269

The finite element machine: An experiment in parallel processing  

NASA Technical Reports Server (NTRS)

The finite element machine is a prototype computer designed to support parallel solutions to structural analysis problems. The hardware architecture and support software for the machine, initial solution algorithms and test applications, and preliminary results are described.

Storaasli, O. O.; Peebles, S. W.; Crockett, T. W.; Knott, J. D.; Adams, L.

1982-01-01

270

Development of an online machining process monitoring system: a case study of the broaching process  

Microsoft Academic Search

This paper presents a new online machining process monitoring system based on the PXI hardware platform and the LabVIEW software\\u000a platform. The whole system is composed of the following interconnected packages: sensing, triggering, data acquisition, characterisation,\\u000a condition monitoring and feature extraction packages. Several signal processing methods, namely, cross-correlation, resample,\\u000a short-time Fourier transform (STFT) and statistical process control, are developed to

D. Shi; D. A. Axinte; N. N. Gindy

2007-01-01

271

Fabrication of micro ball joint by using micro-EDM and electroforming  

Microsoft Academic Search

Miniature products are useful in present-day industrial applications. In the area of micro machine, micro transmissions and linkages are needed. The micro transmissions such as gear and rack can be made by wire-cut, electric discharge machining (micro-EDM), injection molding, etc. Comparatively, mechanical linkages such as bearing or ball joint are much difficult to be manufactured due to the need of

Chang-Sheng Lin; Yunn-Shiuan Liao; Yi-Ting Cheng; Yunn-Cheng Lai

2010-01-01

272

Accuracy improvement of wire-EDM by real-time wire tension control  

Microsoft Academic Search

In this paper, a closed-loop wire tension control system for a wire-EDM machine is presented to improve the machining accuracy. Dynamic models of the wire feed control apparatus and wire tension control apparatus are derived to analyze and design the control system. PI controller and one-step-ahead adaptive controller are employed to investigate the dynamic performance of the closed-loop wire tension

Mu-Tian Yan; Pin-Hsum Huang

2004-01-01

273

Cylindrical Wire Electrical Discharge Machining of Metal Bond Diamond Wheels- Part II: Wheel Wear Mechanism  

SciTech Connect

The use of stereo scanning Electron Microscopy (SEM) to investigate the wear mechanism of the wire EDM true metal bond diamond wheel for ceramic grinding is presented. On the grinding wheel, a wedge-shape removal part was machined to enable the examination and measurement of the worn wheel surfaces using the stereo SEM. The stereo SEM was calibrated by comparing results of depth profile of a wear groove with the profilometer measurements. On the surface of the grinding wheel after wire EDM truing and before grinding, the diamond protruding heights were measured in the level of 35 {micro}m, comparing to the 54 {micro}m average size of the diamond in the grinding wheel. The gap between the EDM wire and rotating grinding wheel is estimated to be about 35 to 40 {micro}m. This observation indicates that, during the wire EDM, electrical sparks occur between the metal bond and EDM wire, which leaves the diamond protruding in the gap between the wire and wheel. The protruding diamond is immediately fractured at the start of the grinding process, even under a light grinding condition. After heavy grinding, the grinding wheel surface and the diamond protrusion heights are also investigated using the stereo SEM. The height of diamond protrusion was estimated in the 5 to 15 {micro}m range. This study has demonstrated the use of stereo SEM as a metrology tool to study the grinding wheel surface.

McSpadden, SB

2002-01-22

274

Dennis Brown, Manager GTRI Machine Services Department  

E-print Network

-fashioned manual equipment with new computer-based tools like the Fadal Vertical Machining Center, Mori Seiki CNC Lathe, Charmilles 290P Wire EDM and HD 20-Hole Driller and the Omax Waterjet gives us the opportunity

Bennett, Gisele

275

Contamination-Free Electrical-Discharge Machining  

NASA Technical Reports Server (NTRS)

Contamination of parts by electrical-discharge machining (EDM) almost completely eliminated by reversing flow of coolant. Flow reversed from usual direction so coolant carries contaminants out through passage in electrode. Coolant for reverse flow is pressurized dichlorodifluoromethane vapor.

Schmidt, Mark G.

1987-01-01

276

Characterization of electric discharge machining, subsequent etching and shot-peening as a surface treatment for orthopedic implants  

NASA Astrophysics Data System (ADS)

Presented work aims at multi-method characterization of combined surface treatment of Ti-6Al-4V alloy for biomedical use. Surface treatment consists of consequent use of electric discharge machining (EDM), acid etching and shot peening. Surface layers are analyzed employing scanning electron microscopy and energy dispersive X-ray spectroscopy. Acid etching by strong Kroll's reagent is capable of removing surface layer of transformed material created by EDM. Acid etching also creates partly nanostructured surface and significantly contributes to the enhanced proliferation of the bone cells. The cell growth could be positively affected by the superimposed bone-inspired structure of the surface with the morphological features in macro-, micro- and nano-range. Shot peening significantly improves poor fatigue performance after EDM. Final fatigue performance is comparable to benchmark electropolished material without any adverse surface effect. The proposed three-step surface treatment is a low-cost process capable of producing material that is applicable in orthopedics.

Strsk, Josef; Havlkov, Jana; Ba?kov, Lucie; Harcuba, Petr; Mhaede, Mansour; Jane?ek, Milo

2013-09-01

277

Search for a permanent EDM using laser cooled radioactive atom  

Microsoft Academic Search

An Electric Dipole Moment (EDM) of the elementary particle is a good prove to observe the phenomena beyond the Standard Model. A non-zero EDM shows the violation of the time reversal symmetry, and under the CPT invariance it means the CP violation. In paramagnetic atoms, an electron EDM results in an atomic EDM enhanced by the factor of the 3rd

Y. Sakemi; K. Harada; T. Hayamizu; M. Itoh; H. Kawamura; S. Liu; H. S. Nataraj; A. Oikawa; M. Saito; T. Sato; H. P. Yoshida; T. Aoki; A. Hatakeyama; T. Murakami; K. Imai; K. Hatanaka; T. Wakasa; Y. Shimizu; M. Uchida

2011-01-01

278

CRADA final report for CRADA number Y-1293-0185: Process modelling and machining operations development  

SciTech Connect

Lockheed Martin Energy Systems, Inc. and Ferro Corporation (formerly W. R. Grace, the original CRADA partner) have collaborated on an effort to develop techniques and processes for the cost-effective machining of ceramic components. The purpose of this effort was to develop a machining model, and grinding equipment machines and techniques for fabricating precision ceramic components. This project was designed to support Department of Energy (DOE) technical needs in manufacturing hard materials as well as enabling U.S. industry to maintain a position of leadership in the production of precision grinding machines and the machining of structural ceramic components.

Arnold, J.B.; Kruse, K.L.; Stone, P.K. [and others

1996-09-16

279

A review of machining monitoring systems based on artificial intelligence process models  

Microsoft Academic Search

Many machining monitoring systems based on artificial intelligence (AI) process models have been successfully developed in\\u000a the past for optimising, predicting or controlling machining processes. In general, these monitoring systems present important\\u000a differences among them, and there are no clear guidelines for their implementation. In order to present a generic view of\\u000a machining monitoring systems and facilitate their implementation, this

Jose Vicente Abellan-Nebot; Fernando Romero Subirn

2010-01-01

280

Landers, Ulsoy, and Furness 1 Process Monitoring and Control of Machining Operations  

E-print Network

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 #12;Landers, Ulsoy, and Furness 2 1 INTRODUCTION Machining operations (e.g., drilling, millingLanders, Ulsoy, and Furness 1 Process Monitoring and Control of Machining Operations Robert G) are shape transformation processes where metal is removed from a stock of material to produce a part

Landers, Robert G.

281

FEATURE EXTRACTION AND ASSESSMENT USING WAVELET PACKETS FOR MONITORING OF MACHINING PROCESSES  

Microsoft Academic Search

Monitoring of machining processes is a classic and yet unsolved problem in manufacturing engineering. This paper introduces a new method of feature extraction and feature assessment using a wavelet packet transform for monitoring of machining processes. First, the principles of wavelet transforms are briefly described by comparing to the Fourier transform, followed by a discussion on the properties of wavelet

Y. Wu; R. Du

1996-01-01

282

GRINDING MACHINES Grinding is the process of removing metal by the application  

E-print Network

TC 9-524 Chapter 5 GRINDING MACHINES Grinding is the process of removing metal by the application, the process is as much a cutting action as drilling, milling, and lathe turning. The grinding machine supports projections from castings and stampings; and cleaning, polishing, and buffing surfaces. Once strictly

Gellman, Andrew J.

283

An experimental investigation of cylindrical wire electrical discharge turning process  

Microsoft Academic Search

The cylindrical wire electrical discharge turning (CWEDT) process was developed to generate precise cylindrical forms on hard,\\u000a difficult to machine materials. A precise, flexible, and corrosion-resistant submerged rotary spindle was designed and added\\u000a to a conventional five-axis CNC wire electrical discharge machine (EDM) to enable the generation of free-form cylindrical\\u000a geometries. The hardness and strength of the work material are

Mohammad Jafar Haddad; Fereshteh Alihoseini; Mostafa Hadi; Meysam Hadad; Alireza Fadaei Tehrani; Aminollah Mohammadi

2010-01-01

284

Neutron-Electron EDM Correlations in Supersymmetry and Prospects for EDM Searches  

E-print Network

Motivated by recent progress in experimental techniques of electric dipole moment (EDM) measurements, we study correlations between the neutron and electron EDMs in common supersymmetric models. These include minimal supergravity (mSUGRA) with small CP phases, mSUGRA with a heavy SUSY spectrum, the decoupling scenario and split SUSY. In most cases, the electron and neutron EDMs are found to be observable in the next round of EDM experiments. They exhibit certain correlation patterns. For example, if d_n ~ 10^{-27} e cm is found, d_e is predicted to lie in the range 10^{-28}-10^{-29} e cm.

S. Abel; O. Lebedev

2006-01-13

285

Laser cladding of copper-based materials for building electrical discharge machining electrode  

Microsoft Academic Search

The paper investigates the feasibility of laser cladding of copper-based materials. As an application aspect of rapid prototyping (RP), the process could be used to build electrodes for electrical discharge machining (EDM). Two types of material system-Cu\\/W (with and without nickel) and Cu\\/B4C (with and without nickel) in certain compositions were studied. The laser cladding was conducted in a 3000W

Y. Tang; Li Lu; Jerry Y. Fuh; Yoke-San Wong; M. Gupta; H. Zhu

2002-01-01

286

Bulk-Metal-Based Mems Fabricated by Micro-Electro-Discharge Machining  

Microsoft Academic Search

This paper presents the recent development of micro-electro-mechanical systems (MEMS) and devices realized by planar micromachining of metal foils. New types of cardiac stents including sensor-integrated antenna stents, a micromachined Kelvin probe with an integrated actuator, an intraluminal flow sensor cuff, and a mechanically\\/chemically robust capacitive pressure sensor are reported. Micro-electro-discharge machining (muEDM) and the modified processes were used for

Kenichi Takahata; Yogesh B. Gianchandani

2007-01-01

287

An improved mixed integer linear formulation and lower bounds for minimizing makespan on a flow shop with batch processing machines  

Microsoft Academic Search

This paper considers a flow shop scheduling problem with batch processing machines. Each batch processing machine has a limited\\u000a capacity and can process a group of jobs, each of them having a different known capacity requirement, simultaneously. Job\\u000a processing time on each machine is known and arbitrary. The processing time of a batch on each machine is the longest processing

Ali Husseinzadeh Kashan; Behrooz Karimi

2009-01-01

288

Flotation machine and process for removing impurities from coals  

DOEpatents

The present invention is directed to a type of flotation machine that combines three separate operations in a single unit. The flotation machine is a hydraulic separator that is capable of reducing the pyrite and other mineral matter content of a coal. When the hydraulic separator is used with a flotation system, the pyrite and certain other minerals particles that may have been entrained by hydrodynamic forces associated with conventional flotation machines and/or by the attachment forces associated with the formation of microagglomerates are washed and separated from the coal.

Szymocha, Kazimierz (Edmonton, CA); Ignasiak, Boleslaw (Edmonton, CA); Pawlak, Wanda (Edmonton, CA); Kulik, Conrad (Newark, CA); Lebowitz, Howard E. (Mountain View, CA)

1997-01-01

289

Flotation machine and process for removing impurities from coals  

DOEpatents

The present invention is directed to a type of flotation machine that combines three separate operations in a single unit. The flotation machine is a hydraulic separator that is capable of reducing the pyrite and other mineral matter content of a coal. When the hydraulic separator is used with a flotation system, the pyrite and certain other minerals particles that may have been entrained by hydrodynamic forces associated with conventional flotation machines and/or by the attachment forces associated with the formation of microagglomerates are washed and separated from the coal.

Szymocha, Kazimierz (Edmonton, CA); Ignasiak, Boleslaw (Edmonton, CA); Pawlak, Wanda (Edmonton, CA); Kulik, Conrad (Newark, CA); Lebowitz, Howard E. (Mountain View, CA)

1995-01-01

290

Flotation machine and process for removing impurities from coals  

DOEpatents

The present invention is directed to a type of flotation machine that combines three separate operations in a single unit. The flotation machine is a hydraulic separator that is capable of reducing the pyrite and other mineral matter content of a coal. When the hydraulic separator is used with a flotation system, the pyrite and certain other minerals particles that may have been entrained by hydrodynamic forces associated with conventional flotation machines and/or by the attachment forces associated with the formation of microagglomerates are washed and separated from the coal. 4 figs.

Szymocha, K.; Ignasiak, B.; Pawlak, W.; Kulik, C.; Lebowitz, H.E.

1997-02-11

291

Flotation machine and process for removing impurities from coals  

DOEpatents

The present invention is directed to a type of flotation machine that combines three separate operations in a single unit. The flotation machine is a hydraulic separator that is capable of reducing the pyrite and other mineral matter content of a coal. When the hydraulic separator is used with a flotation system, the pyrite and certain other mineral particles that may have been entrained by hydrodynamic forces associated with conventional flotation machines and/or by the attachment forces associated with the formation of microagglomerates are washed and separated from the coal. 4 figs.

Szymocha, K.; Ignasiak, B.; Pawlak, W.; Kulik, C.; Lebowitz, H.E.

1995-12-05

292

System Identification of Wire Electrical Discharge Machining  

Microsoft Academic Search

In wire electrical discharge machining (wire-EDM), it is very important to restrain the vibration of the tool wire electrode for the improvement of machining accuracy. In this paper, investigation is carried out toward the dynamic wire vibration mechanism and a mathematical model is derived. This model is compared with experimental results. The measured displacement of a wire electrode in machining

N. Mohri; H. Yamada; K. Furutani; T. Narikiyo; T. Magara

1998-01-01

293

Ultrasonic vibration electrical discharge machining in gas  

Microsoft Academic Search

A new method of ultrasonic vibration electrical discharge machining (UEDM) in gas is proposed in this paper. It is shown that electrical discharge machining (EDM) with ultrasonic aid can be achieved well in a gas medium. The tool electrode is formed into a thin-walled pipe, and a high pressure gas medium is supplied through it. During machining, ultrasonic vibration of

Q. H Zhang; J. H Zhang; J. X Deng; Y Qin; Z. W Niu

2002-01-01

294

CKM benchmarks for electron EDM experiments  

E-print Network

All current experiments searching for an electron EDM d_e are performed with atoms and diatomic molecules. Motivated by significant recent progress in searches for an EDM-type signal in diatomic molecules with an uncompensated electron spin, we provide an estimate for the expected signal in the Standard Model due to the CKM phase. We find that the main contribution originates from the effective electron-nucleon operator $\\bar{e} i\\gamma_5 e \\bar{N}N$, induced by a combination of weak and electromagnetic interactions at $O(G_F^2\\alpha^2)$, and not by the CKM-induced electron EDM itself. When the resulting atomic P,T-odd mixing is interpreted as an {\\it equivalent} electron EDM, this estimate leads to the benchmark $d_e^{equiv}(CKM) \\sim 10^{-38}$ ecm.

Pospelov, Maxim

2013-01-01

295

CKM benchmarks for electron EDM experiments  

E-print Network

All current experiments searching for an electron EDM d_e are performed with atoms and diatomic molecules. Motivated by significant recent progress in searches for an EDM-type signal in diatomic molecules with an uncompensated electron spin, we provide an estimate for the expected signal in the Standard Model due to the CKM phase. We find that the main contribution originates from the effective electron-nucleon operator $\\bar{e} i\\gamma_5 e \\bar{N}N$, induced by a combination of weak and electromagnetic interactions at $O(G_F^2\\alpha^2)$, and not by the CKM-induced electron EDM itself. When the resulting atomic P,T-odd mixing is interpreted as an {\\it equivalent} electron EDM, this estimate leads to the benchmark $d_e^{equiv}(CKM) \\sim 10^{-38}$ ecm.

Maxim Pospelov; Adam Ritz

2013-11-28

296

Electric-Discharge Machining Techniques for Evaluating Tritium Effects on Materials  

SciTech Connect

In this investigation, new ways to evaluate the long-term effects of tritium on the structural properties of components were developed. Electric-discharge machining (EDM) techniques for cutting tensile and fracture toughness samples from tritium exposed regions of returned reservoirs were demonstrated. An existing electric discharge machine was used to cut sub-size tensile and fracture toughness samples from the inside surfaces of reservoir mockups. Tensile properties from the EDM tensile samples were similar to those measured using full-size samples cut from similar stock. Although the existing equipment could not be used for machining tritium-exposed hardware, off-the shelf EDM units are available that could. With the right equipment and the required radiological controls in place, similar machining and testing techniques could be used to directly measure the effects of tritium on the properties of material cut from reservoir returns. Stress-strain properties from tritium-exposed reservoirs would improve finite element modeling of reservoir performance because the data would be representative of the true state of the reservoir material in the field. Tensile data from samples cut directly from reservoirs would also complement existing shelf storage and burst test data of the Life Storage Program and help answer questions about a specific reservoir's processing history and properties.

Morgan, M.J.

2003-11-07

297

Electrical Discharge Machining Techniques for Evaluating the Effects of Tritium on Materials  

SciTech Connect

In this investigation, new ways to evaluate the long-term effects of tritium on the structural properties of components were developed. Electric discharge machining (EDM) techniques for cutting tensile and fracture toughness samples from the tritium-exposed regions of returned reservoirs were demonstrated. An existing electric discharge machine was used to cut sub-size tensile and fracture toughness samples from the inside walls of reservoir mock-ups. Tensile properties from the EDM tensile samples were similar to those measured using full-size samples cut from similar stock. Although the existing equipment could not be used for machining tritium-exposed hardware, off-the-shelf EDM units are available that could. With the right equipment and the required radiological controls in place, similar machining and testing techniques could be used to directly measure the effects of tritium on the properties of material cut from reservoir returns. Stress-strain property data from tritium-exposed reservoirs would improve finite-element modeling of reservoir performance because the data are representative of the true state of the reservoir material in the field. Tensile data from samples cut directly from reservoirs complement existing shelf storage and burst test data of the Life Storage Program and help answer questions about a specific reservoir's processing history and properties.

IMRICH, KENNETH

2004-03-24

298

A MONTE CARLO SEQUENTIAL ESTIMATION OF POINT PROCESS OPTIMUM FILTERING FOR BRAIN MACHINE INTERFACES  

E-print Network

1 A MONTE CARLO SEQUENTIAL ESTIMATION OF POINT PROCESS OPTIMUM FILTERING FOR BRAIN MACHINE Monte Carlo Sequential Estimation for Point Processes.................................................29 Simulation of Monte Carlo Sequential Estimation on Neural Spike Train Decoding............32 Interpretation

Slatton, Clint

299

Overview of Muon and EDM Experiments  

E-print Network

BOSTON UNIVERSITY Overview of Muon and EDM Experiments What we have learned from BNL E821 B. Lee § Results from E821 § The muon EDM § Implications for future experiments at JHF § Summary and Conclusions B for § Electron: To the level of the experimental error, $ ppb B I ¡prq Ef stE X s a s %u¦ B I ¡ v Ve q Wxwy 5

Roberts, B. Lee

300

Surface integrity evolution from main cut mode to finish trim cut mode in W-EDM of shape memory alloy  

NASA Astrophysics Data System (ADS)

Shape memory alloys such as Nitinol are widely used in medical, aerospace, actuator, and machine tool industries. However, Nitinol is a very difficult-to-machine material due to the superelasticity, high ductility, and severe strain-hardening. The machined surface should have tailored micro texture to enhance cell adhesion. This study explores the process capability of W-EDM (DI-water based dielectric) in machining Ni50.8Ti49.2 by one main cut (MC) mode followed by four trim cut (TC) modes. Experimental results show that the 6-sigma distributions of Ra are very different between MC mode and finish TC mode. Thick white layers (2-8 ?m) with microcracks in MC mode and very thin white layers (0-2 ?m) free of those defects in finish TC mode can be observed. However, microcracks would not propagate into the heat affected zone (HAZ) below the white layer. The microhardness of white layer by TC mode is about 50% higher than that by MC mode. In addition, Ni is the dominant element for the measured microhardness.

Liu, J. F.; Li, L.; Guo, Y. B.

2014-07-01

301

A NEW METHOD FOR MACHINING OF ELECTRICALLY NONCONDUCTIVE WORKPIECES USING ELECTRIC DISCHARGE MACHINING TECHNIQUE  

Microsoft Academic Search

In this study, a new method for machining of nonconductive ceramic workpieces in electric discharge machining (EDM) was developed. Machining surfaces of nonconductive workpieces were coated with a conductive layer (CL) and graphite powder was added to dielectric fluid for machining. Al2O3, ZrO2, SiC, B4C and glass workpiece samples were machined by using the method. Different machining conditions were tested

Gokhan Kucukturk; Can Cogun

2010-01-01

302

Fermion EDMs with minimal flavor violation  

NASA Astrophysics Data System (ADS)

We study the electric dipole moments (EDMs) of fermions in the standard model supplemented with right-handed neutrinos and its extension including the neutrino seesaw mechanism under the framework of minimal flavor violation (MFV). In the quark sector, we find that the current experimental bound on the neutron EDM does not yield a significant restriction on the scale of MFV. In addition, we consider how MFV may affect the contribution of the strong theta-term to the neutron EDM. For the leptons, the existing EDM data also do not lead to strict limits if neutrinos are Dirac particles. On the other hand, if neutrinos are Majorana in nature, we find that the constraints become substantially stronger. Moreover, the results of the latest search for the electron EDM by the ACME Collaboration are sensitive to the MFV scale of order a few hundred GeV or higher. We also look at constraints from CP -violating electron-nucleon interactions that have been probed in atomic and molecular EDM searches.

He, Xiao-Gang; Lee, Chao-Jung; Li, Siao-Fong; Tandean, Jusak

2014-08-01

303

Fermion EDMs with Minimal Flavor Violation  

E-print Network

We study the electric dipole moments (EDMs) of fermions in the standard model supplemented with right-handed neutrinos and its extension including neutrino seesaw mechanism under the framework of minimal flavor violation (MFV). In the quark sector, we find that the current experimental bound on the neutron EDM does not yield a significant restriction on the scale of MFV. In addition, we consider how MFV may affect the contribution of the strong theta-term to the neutron EDM. For the leptons, the existing EDM data also do not lead to strict limits if neutrinos are Dirac particles. On the other hand, if neutrinos are Majorana in nature, we find that the constraints become substantially stronger. Moreover, the results of the latest search for the electron EDM by the ACME Collaboration are sensitive to the MFV scale of order a few hundred GeV or higher. We also look at constraints from $CP$-violating electron-nucleon interactions that have been probed in atomic and molecular EDM searches.

Xiao-Gang He; Chao-Jung Lee; Siao-Fong Li; Jusak Tandean

2014-06-27

304

Fabrication of Surface Modification Layer on Stainless Steel by Electrical Discharge Machining  

Microsoft Academic Search

A stainless steel (SUS 304) was machined by Electrical Discharge Machining (EDM) with a sialon and chromium electrode. According to the EDMed conditions, the deformed stainless steel surface turned to the coated surface with an electrode components. The following experimental factors were investigated to produce the modified surface: electrode polarity, work atmosphere, peak current, pulse duration and duty factor. In

Y. Fukuzawa; Yo Kojima; T. Tani; E. Sekiguti; N. Mohri

1995-01-01

305

Field-emission-assisted approach to dry micro-electro-discharge machining of carbon-nanotube forests  

NASA Astrophysics Data System (ADS)

This work investigates dry micro-electro-discharge machining (?EDM) of vertically aligned carbon nanotube (CNT) forests that are used as cathodes in the process, as opposed to conventional ?EDM where the material to be machined forms the anode, toward achieving higher precision in the patterned microstructures. The new configuration with the reversed polarity is observed to generate higher discharge currents in the process, presumably due to effective field-emission from CNTs. This effect allows the process to be performed at very low discharge energies, approximately 80 smaller than in the conventional normal-polarity case, with the machining voltage and tolerance down to 10 V and 2.5 ?m, respectively, enabling high-precision high-aspect-ratio micropatterning in the forests. The new approach is also demonstrated to make the process faster, cleaner, and more stable than conventional processing. Spectroscopic analyses of the forests processed by reverse ?EDM show no evidence of significant crystalline deterioration or contamination in the CNTs.

Saleh, Tanveer; Dahmardeh, Masoud; Bsoul, Anas; Nojeh, Alireza; Takahata, Kenichi

2011-11-01

306

Software Components for Production Process on Plasma-cutting Machine "Crystal".  

E-print Network

. The price of the new plasma-cutter is significant for production that is surviving in the new worldSoftware Components for Production Process on Plasma-cutting Machine "Crystal". Project description a part of an upgrade project for a plasma-cutting machine "Crystal". Software components

Weske, Mathias

307

Experimental characterization of the inner surface in micro-drilling of spray holes: A comparison between ultrashort pulsed laser and EDM  

NASA Astrophysics Data System (ADS)

In this research, the inner surface characteristics of micro-drilled holes of fuel injector nozzles were analyzed by Shear Force Microscopy (SHFM). The surface texture was characterized by maximum peak-to-valley distance and periodicity whose dimensions were related to the adopted energy. 180 m diameter holes were drilled using ultrashort pulsed laser process using pulse energies within the range of 10-50 J. Laser ablated surfaces in the tested energy range offer a smooth texture with a peculiar periodic structure with a variation in height between 60 and 90 nm and almost constant periodicity. The Scanning Electron Microscopy (SEM) photograph of the Laser Induced Periodic Surface Structure (LIPSS) showed the co-existence of Low Spatial Frequency LIPSS (LSFL) and High Spatial Frequency LIPSS (HSFL). A comparative analysis was carried out between the highest laser pulse energy in the tested range energy laser drilling which enables the shortest machining time and micro-Electrical Discharge Machining (-EDM). On the contrary, results showed that surfaces obtained by electro-erosion are characterized by a random distribution of craters with a total excursion up to 1.5 m with a periodicity of 10 m. The mean-squared surface roughness (Rq) derived from the scanned maps ranges between 220 and 560 nm for -EDM, and between 50 and 100 nm for fs-pulses laser drilling.

Romoli, L.; Rashed, C. A. A.; Fiaschi, M.

2014-03-01

308

Evaluation of a Prototype Fish Cleaning Machine With Proposals for a Commercial Processing Line  

Microsoft Academic Search

when the lining is pigmented as in the case of whiting, Merluccius bilinearis, prior to processing in a meat\\/bone separator. As a solution to heading and fully cleaning whiting, a LaPine Model 22 smelt processing machine1 was extensively modified (Mendelsohn et aI., 1977). Preliminary Results The modified machine (Fig. I) was laboratory tested for processing vari ous sizes of whiting

J. M. MENDELSOHN; J. G. CALLAN

309

The control system of the Blind Hole Processing Machine based on PLC and touch-panel  

Microsoft Academic Search

This article uses the working process of the Blind Hole Processing Machine as a reference object, describes a kind of automatic blind hole processing machine control system based on Siemens S7-200PLC and Siemens TP177B, at the same time discusses the stroke control of servo motor Combining the advantage of the PLC's flexible control interface with the touch-panel visual programming, this

Changhong Jiang; Lianfang Liu; Huiqun Liang; Shaozhong Lu

2010-01-01

310

The Evolutionary Design Model (EDM) for the design of complex engineered systems : Masdar City as a case study  

E-print Network

This thesis develops a framework for constructing an Evolutionary Design Model (EDM) that would enhance the design of complex systems through an efficient process. The framework proposed is generic and suggests a group of ...

Alfaris, Anas (Anas Faris)

2009-01-01

311

Hot Machining of Hardened Steels with Coated Carbide Inserts  

Microsoft Academic Search

Problem statement: The benefits of easier manufacture of hardened ste el components can be substantial in terms of reduced machining costs and lead times compared to the traditional route involving machining of the annealed state followed by heat treatment, grinding\\/EDM and manual finishing. But machinability of hard material throu gh conventional machining is hindered due to excessive wear of the

M. A. Lajis; A. K. M. N. Amin; A. N. M. Karim; H. C. D. M. Radzi; T. L. Ginta

2009-01-01

312

Fabrication of high aspect ratio microstructure arrays by micro reverse wire-EDM  

NASA Astrophysics Data System (ADS)

In this paper, a machining technique to fabricate high aspect ratio microstructure arrays of a total volume less than 1 mm3 is developed. A method for determining the appropriate tension of the micro brass wire of the micro wire-EDM mechanism designed in our previous study is proposed, and a design for suppressing the vibration of the wire is implemented. In addition, a machining approach coined 'reverse wire-EDM' is developed. The micro wire-EDM mechanism is mounted on the worktable rather than on the machine head while the micro workpiece is clamped on the spindle instead of the worktable by a micro chuck. Machining is carried out by a horizontal moving micro brass wire of 20 m diameter located beneath the micro workpiece to accelerate the removal of debris and to eliminate the heat accumulated in the micro gap during machining. The possible occurrence of short circuit discharge and thermal deformation of the machined part are therefore minimized. Experiments are conducted to machine various high aspect ratio miniature structures including a microstructure array of ten 10 m sharp-edge lamellae at the tip, a microstructure array of ten 10 m uniform thickness lamellae and a microstructure array of ten by ten 21 m squared pillars. It is found that a microstructure array of an aspect ratio more than 33 is satisfactorily and precisely fabricated. The dimensional accuracy and geometric accuracy are less than 0.6 and 1.0 m, respectively, while the surface roughness Rmax is kept within 0.44 m.

Liao, Yunn-Shiuan; Chen, Shun-Tong; Lin, Chang-Sheng; Chuang, Tzung-Jen

2005-08-01

313

A high-efficiency approach for fabricating mass micro holes by batch micro EDM  

NASA Astrophysics Data System (ADS)

This work is a follow-up study based on previous research. The study presents a novel approach for effective production of mass micro holes. Initially, a set of micro w-EDM mechanisms is designed and mounted on the developed precise tabletop CNC machine tool to fabricate the micro electrode array. The tension of the micro wire is precisely controlled by a magnetic force. Furthermore, micro vibrations of the wire during discharging are effectively suppressed by the developed vibration suppression system. To fabricate the mass micro holes, a microstructure array with a high-aspect ratio of 10 10 micro squared electrodes, width and height of 21 m and 700 m, respectively, for each electrode and 24 m spacing between two electrodes is fabricated first by using the proposed 'reverse w-EDM' machining strategy. The electrodes array is directly utilized to drill the mass micro holes by bath micro EDM on the same machine. An array of 900 through-holes of the same size is successfully fabricated via the modified peck-drilling method on a 30 m thick stainless-steel plate. A tip at the free end of the micro electrode is designed and fabricated as a circular-pyramid shape. Experimental results verified that the spiky end form eliminates debris adhering to the edges of the micro holes. Analytical results demonstrate satisfactory hole geometric accuracy, dimensional accuracy and surface roughness. Furthermore, mass micro holes can be fabricated efficiently using the proposed technique.

Chen, Shun-Tong

2007-10-01

314

Wire vibration, bowing, and breakage in wire electrical discharge machining  

NASA Astrophysics Data System (ADS)

This article provides an analysis of the wire electrical discharge machining (EDM) process. The causes of wire vibration, bowing, and breakage are identified. The cross sectional configuration of an eroded wire is derived from basic physics under the assumption that the erosion rate is constant. This configuration is verified experimentally with further explanation as to why numerous experimental studies have yielded different configurations. A computational model has been developed that can evaluate the systematic effects that lead to wire breakage by determining the stress induced by wire erosion and the stress induced by the sparks during the operation of a wire-cutting EDM machine. This model is also capable of determining the extent of wire bowing and vibrations in these machines but only in the frontal direction. The model is supported by data from experiments performed on an AGIECUT 612 wire machine cutting a 10 mm high copper bar with a 0.15 mm brass wire to acquire wire breakage data. The nearly parabolic shape of the bowed wire agrees with the results of other authors making more restrictive assumptions.

Arunachalam, C.; Aulia, M.; Bozkurt, B.; Eubank, P. T.

2001-04-01

315

Note on the Electron EDM W. R. Johnson  

E-print Network

Note on the Electron EDM W. R. Johnson October 25, 2002 Abstract This is a note on the setup of an electron EDM calculation and Schiff's Theorem. 1 Basic Relations The well-known relativistic interaction that the electron has an electric dipole moment (EDM) d, the corresponding relativistic interaction with an electric

Johnson, Walter R.

316

Search for electron EDM in molecular experiments: new  

E-print Network

Search for electron EDM in molecular experiments: new objects and importance of precise Electron EDM · On diatomic hydride cations with ground state 1 (, , ...- states) Nuclear Schiff Moment electron is 3/2, one cannot expect great enhancement of electron EDM. Unfortunately, there are some more

Titov, Anatoly

317

PNC in Atoms and Electron EDM Walter Johnson  

E-print Network

PNC in Atoms and Electron EDM Walter Johnson Notre Dame University September 16, 2002 Abstract symmetry, is discussed along with the corresponding limit on the electron EDM. ­ ND ­ 2002 #12;Highlights, designed to detect an atomic electric dipole moment (EDM), which signals violation of time- reversal

Johnson, Walter R.

318

The role of EDM in information management within SMEs  

Microsoft Academic Search

Electronic document management (EDM) is a new form of information management. EDM is described to have certain business values in organizations, but no research has been found about EDM and Small and Medium sized Enterprises (SME). In this paper we present an ongoing investigation in two SMEs guided by the following research questions: \\

Erik A. M. Borglund; Anneli Sundqvist

2007-01-01

319

Study on the nano-powder-mixed sinking and milling micro-EDM of WC-Co  

Microsoft Academic Search

Present study investigates the feasibility of improving surface characteristics in the micro-electric discharge machining\\u000a (EDM) of cemented tungsten carbide (WCCo), a widely used die and mould material, using graphite nano-powder-mixed dielectric.\\u000a In this context, a comparative analysis has been carried out on the performance of powder-mixed sinking and milling micro-EDM\\u000a with view of obtaining smooth and defect-free surfaces. The surface

Muhammad Pervej Jahan; Mustafizur Rahman; Yoke San Wong

2011-01-01

320

29 CFR 570.61 - Occupations in the operation of power-driven meat-processing machines and occupations involving...  

Code of Federal Regulations, 2014 CFR

...and jawpullers; skinning machines; horizontal rotary washing machines; casing-cleaning...small capacity, portable, countertop mixers discussed in 570.62(b)(1) of this chapter when used as a mixer to process materials other than...

2014-07-01

321

29 CFR 570.61 - Occupations in the operation of power-driven meat-processing machines and occupations involving...  

Code of Federal Regulations, 2013 CFR

...and jawpullers; skinning machines; horizontal rotary washing machines; casing-cleaning...small capacity, portable, countertop mixers discussed in 570.62(b)(1) of this chapter when used as a mixer to process materials other than...

2013-07-01

322

29 CFR 570.61 - Occupations in the operation of power-driven meat-processing machines and occupations involving...  

Code of Federal Regulations, 2011 CFR

...and jawpullers; skinning machines; horizontal rotary washing machines; casing-cleaning...small capacity, portable, countertop mixers discussed in 570.62(b)(1) of this chapter when used as a mixer to process materials other than...

2011-07-01

323

29 CFR 570.61 - Occupations in the operation of power-driven meat-processing machines and occupations involving...  

Code of Federal Regulations, 2012 CFR

...and jawpullers; skinning machines; horizontal rotary washing machines; casing-cleaning...small capacity, portable, countertop mixers discussed in 570.62(b)(1) of this chapter when used as a mixer to process materials other than...

2012-07-01

324

Preset Electrodes for Electrical-Discharge Machining  

NASA Technical Reports Server (NTRS)

New electrode holder for electrical-discharge machining (EDM) provides for repeatable loading and setting of many electrodes. New holder is rotating-index tool carrying six, eight, or more electrodes. Before use, all electrodes set with aid of ring surrounding tool, and locked in position with screws. When electrode replaced, EDM operator pulls spring-loaded pin on tool so it rotates about center pin. Fresh electrode then rotated into position against workpiece.

Coker, Bill E.

1987-01-01

325

A Fast Inspection of Tool Electrode and Drilling Depth in EDM Drilling by Detection Line Algorithm  

PubMed Central

The purpose of this study was to develop a novel measurement method using a machine vision system. Besides using image processing techniques, the proposed system employs a detection line algorithm that detects the tool electrode length and drilling depth of a workpiece accurately and effectively. Different boundaries of areas on the tool electrode are defined: a baseline between base and normal areas, a ND-line between normal and drilling areas (accumulating carbon area), and a DD-line between drilling area and dielectric fluid droplet on the electrode tip. Accordingly, image processing techniques are employed to extract a tool electrode image, and the centroid, eigenvector, and principle axis of the tool electrode are determined. The developed detection line algorithm (DLA) is then used to detect the baseline, ND-line, and DD-line along the direction of the principle axis. Finally, the tool electrode length and drilling depth of the workpiece are estimated via detected baseline, ND-line, and DD-line. Experimental results show good accuracy and efficiency in estimation of the tool electrode length and drilling depth under different conditions. Hence, this research may provide a reference for industrial application in EDM drilling measurement.

Huang, Kuo-Yi

2008-01-01

326

Fiber optic diagnostic techniques for the electrical discharge machining process  

E-print Network

on both sides of the electrodes . . 27 12 Setup to observe total optical power emitted by the plasma spark along with the current measurements from the machine 34 13 Total setup for measuring the spectrum of light emitted by a tungsten lamp . 14... Detailed view of how the monochrometer is being used in the system. . 37 FIG U RE Page IS Total setup for measuring the spectrum of light emitted by a tungsten lamp with a light chopper set at a low duty cycle. . . . . . . . 38 16 Total setup for measu...

Pillans, Brandon William

1998-01-01

327

The Electron EDM and EDMs in Two-Higgs-Doublet Models  

E-print Network

Electric dipole moments constitute highly sensitive probes for CP-violating effects beyond the Standard Model. The upper limits obtained in various precision experiments can therefore be used to strongly restrict new physics models. However, relating the experimental information to parameters of a specific model is complicated by the presence of various sources for EDMs as well as large theory uncertainties in some of the relevant matrix elements. In this article, we address both issues for the EDMs of heavy paramagnetic systems, where it is possible to include subleading contributions, thereby model-independently extracting the electron EDM. We furthermore use expressions for the presently phenomenologically relevant EDMs with conservative estimates for the theoretical uncertainties to place constraints on CP-violating phases in the context of Two-Higgs-Doublet models.

Martin Jung

2014-05-25

328

An Investigation of Machining Characteristics in Micro-scale Milling Process  

NASA Astrophysics Data System (ADS)

In this paper, an analytical solution of micro-scale milling process is presented in order to suggest available machining conditions. The size effect should be considered to determine cutting characteristics in micro-scale cutting. The feed per tooth is the most dominant cutting parameter related to the size effect in micro-scale milling process. In order to determine the feed per tooth at which chips can be formed, the finite element method is used. The finite element method is employed by utilizing the Johnson-Cook (JC) model as a constitutive model of work material flow stress. Machining experiments are performed to validate the simulation results by using a micro-machining stage. The validation is conducted by observing cutting force signals from a cutting tool and the conditions of the machined surface of the workpiece.

Ku, Min-Su; Kang, Ik-Soo; Kim, Jeong-Suk

2011-01-01

329

Search for permanent EDM using laser cooled Fr atoms  

NASA Astrophysics Data System (ADS)

The existence of a non-zero electric dipole moment (EDM) implies the violation of time reversal symmetry. As the time-reversal symmetry violation predicted by the Standard Model (SM) for the electron EDM is too small to be observed with current experimental techniques and any a non-zero EDM would indicate new physics beyond the SM. The tiny signal from the electron EDM is enhanced in the heavy atoms such as francium (Fr). We are constructing the laser-cooled Fr factory to search for the electron EDM.

Kawamura, Hirokazu; Aoki, T.; Arikawa, H.; Ezure, S.; Furukawa, T.; Harada, K.; Hatakeyama, A.; Hatanaka, K.; Hayamizu, T.; Imai, K.; Inoue, T.; Ishikawa, T.; Itoh, M.; Kato, T.; Murakami, T.; Nataraj, H. S.; Sato, T.; Shimizu, Y.; Wakasa, T.; Yoshida, H. P.; Sakemi, Y.

2013-03-01

330

Enhanced osteoblast response to electrical discharge machining surface.  

PubMed

The purpose of this study is to investigate the surface characteristics and biocompatibility of titanium (Ti) surfaces modified by wire electrical discharge machining (EDM). EDM surface characteristics were evaluated by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), thin-film X-ray diffractometry (XRD) and contact angle measurements. MC3T3-E1 cell morphology, attachment and proliferation, as well as analysis of osteoblastic gene expressions, on machined surfaces and EDM surfaces were also evaluated. EDM surfaces exhibited high super hydrophilicity, due to high surface energy. XPS and XRD revealed that a passive oxide layer with certain developing thickness onto. EDM surfaces promoted cell attachment, but restrained proliferation. Counted cell numbers increased significantly on the machined surfaces as compared to the EDM surfaces. Real-time PCR analyses showed significantly higher relative mRNA expression levels of osteoblastic genes (ALP, osteocalcin, Runx2, Osterix) in cells cultured on the EDM surfaces as compared to cells cultured on the machined surfaces. PMID:22447066

Otsuka, Fukunaga; Kataoka, Yu; Miyazaki, Takashi

2012-01-01

331

Tradeoffs in Processing Complex Join Queries via Hashing in Multiprocessor Database Machines  

Microsoft Academic Search

In this paper we examine the problem of pro- cessing multi-way join queries (on the order of 10 joins) through hash-based join methods in a shared-nothing database machine. We first discuss how the choice of a format for a complex query can significantly affect performance in a multiprocessor database machine. Several query processing algorithms are then proposed and experimental results

Donovan A. Schneider; David J. Dewitt

1990-01-01

332

Advances in the EDM-DEDM procedure.  

PubMed

The DEDM (difference electron-density modification) algorithm has been described in a recent paper [Caliandro et al. (2008), Acta Cryst. A64, 519-528]: it breaks down the collinearity between model structure phases and difference structure phase estimates. The new difference electron-density produced by DEDM, summed to the calculated Fourier maps, is expected to provide a representation of the full structure that is more accurate than that obtained by the observed Fourier synthesis. In the same paper, the DEDM algorithm was combined with the EDM (electron-density modification) approach to give the EDM-DEDM procedure which, when applied to practical molecular-replacement cases, was able to improve the model structures. In this paper, it is shown that EDM-DEDM suffers from some critical points that did not allow cyclical application of the procedure. These points are identified and modifications are made to allow iteration of the procedure. The applications indicate that EDM-DEDM may become a fundamental tool in protein crystallography. PMID:19237747

Caliandro, Rocco; Carrozzini, Benedetta; Cascarano, Giovanni Luca; Giacovazzo, Carmelo; Mazzone, Anna Maria; Siliqi, Dritan

2009-03-01

333

Progress of the Jila Electron Edm Experiment  

NASA Astrophysics Data System (ADS)

Molecules can be advantageous for the search for the electron electric dipole moment (eEDM) due to the large effective electric field experienced by a bound, unpaired electron. Furthermore, the closely-spaced states of opposite parity make the molecules easy to polarize in the lab frame. The JILA eEDM experiment currently uses HfF^+ molecules in an ion trap to achieve long coherence times to reduce systematics. When an electric field is applied the eEDM signal is proportional to the shift in energy splitting between two Zeeman levels in a low-lying, metastable ^3?_1 state. We have previously shown efficient preparation of trapped HfF^+ molecules in the rovibronic ground state, X^1?^+(v=0,J=0). Here, we demonstrate coherent transfer of population from the ground state to the a^3?_1(v=0, J=1) state through an intermediate ^3?_{0+} state and efficient state read-out using photodissociation. In addition, we have begun to take spectroscopy data of the hyperfine and Zeeman structure of the eEDM science state in the presence of a rotating bias electric field and a magnetic field. A. E. Leanhardt et. al., Journal of Molecular Spectroscopy 270, 1-25 (2011). H. Loh et. al., Journal of Chemical Physics 135, 154308 (2011).

Loh, Huanqian; Cossel, Kevin C.; Grau, Matt; Gresh, Daniel N.; Ni, Kang-Kuen; Ye, Jun; Cornell, Eric A.

2013-06-01

334

Electron EDM Search with Trapped Molecular Ions  

Microsoft Academic Search

A sample of trapped molecular ions offers unique possibilities to search for a permanent electron electric dipole moment (EDM). Specifically, we plan to perform this search using the unpaired electron spins in the ^3delta1 state of trapped HfF^+ molecular ions. The ions will be confined in a linear RF Paul trap, allowing for long electron spin coherence times for increased

Russell Stutz; Huanqian Loh; Laura Sinclair; Eric Cornell

2008-01-01

335

An Adaptive Control of Ultraprecision Machining with an In-Process Micro-Sensor  

NASA Astrophysics Data System (ADS)

This paper presents an in-process status monitoring method for ultraprecision machining system and an adaptive control system equipped with the function. The crux of this method is an effective in-process micro sensor which can detect physical behavior around the cutting point during ultraprecision machining process. In this study, we develop a micro-miniaturized platinum resistance thermometry-type sensor with micro-fabrication process and then mount it on the rake surface of a single diamond tool tip nearby the cutting point. Through a series of cutting experiments with an ultraprecision diamond turning machine, we evaluate the developed sensor. As a result, experimental results confirm that the developed sensor has useful characteristics such as high sensitivity, compactness and quick response. In addition, we realize an adaptive control system for ulatraprecision machining process. The developed system maintains a constant temperature around the cutting point by controlling the cutting speed. Adaptive control experiment results confirm the developed system has high potential for detecting small thermal and small dynamic behavior of the cutting point during ultraprecision machining process.

Hayashi, Mamoru; Yoshioka, Hayato; Shinno, Hidenori

336

Hardening effect on machined surface for precise hard cutting process with consideration of tool wear  

NASA Astrophysics Data System (ADS)

During hard cutting process there is severe thermodynamic coupling effect between cutting tool and workpiece, which causes quenching effect on finished surfaces under certain conditions. However, material phase transformation mechanism of heat treatment in cutting process is different from the one in traditional process, which leads to changes of the formation mechanism of damaged layer on machined workpiece surface. This paper researches on the generation mechanism of damaged layer on machined surface in the process of PCBN tool hard cutting hardened steel Cr12MoV. Rules of temperature change on machined surface and subsurface are got by means of finite element simulation. In phase transformation temperature experiments rapid transformation instrument is employed, and the effect of quenching under cutting conditions on generation of damaged layer is revealed. Based on that, the phase transformation points of temperature under cutting conditions are determined. By experiment, the effects of cutting speed and tool wear on white layer thickness in damaged layer are revealed. The temperature distribution law of third deformation zone is got by establishing the numerical prediction model, and thickness of white layer in damaged layer is predicted, taking the tool wear effect into consideration. The experimental results show that the model prediction is accurate, and the establishment of prediction model provides a reference for wise selection of parameters in precise hard cutting process. For the machining process with high demanding on surface integrity, the generation of damaged layer on machined surface can be controlled precisely by using the prediction model.

Yue, Caixu; Liu, Xianli; Ma, Jing; Liu, Zhaojing; Liu, Fei; Yang, Yongheng

2014-11-01

337

Non-traditional ProcessingNon traditional Processing ME 4210: Manufacturing Processes and Engineering  

E-print Network

4210: Manufacturing Processes and Engineering Prof. J.S. Colton © GIT 2009 9 #12;Wire EDM ME 4210: Manufacturing Processes and Engineering Prof. J.S. Colton © GIT 2009 10 #12;Wire EDM PartsWire EDM Parts ME 4210

Colton, Jonathan S.

338

Electrical Discharge Machining in Gas  

Microsoft Academic Search

In this paper, we show that electrical discharge machining (EDM) can be achieved in gas. With the help of a high-pressure gas flow supplied through a thin-walled pipe electrode, the molten workpiece material can be removed and flushed out of the working gap without being reattached to the electrode surfaces. The greatest advantage of this technique is that the tool

Masanori Kunieda; Masahiro Yoshida; Norio Taniguchi

1997-01-01

339

Installation and Implementation of an In-Process Coordinate Measuring Machine (CMM)  

SciTech Connect

This report documents the work accomplished during the installation and implementation of the in-process Coordinate Measuring Machine (CMM) in Department A. A wealth of knowledge has been gained in solving the many technical issues that delayed the partial implementation of this CMM. The work completed thus far lead to the successfully calibrated in-process CMM workstation. A great deal of current and future work has been outlined in the following pages that shall be used as a guide for the full implementation of this CMM with machining processes in Department A.

Johnston, Derek

2008-06-16

340

Fabrication of series-pattern micro-disk electrode and its application in machining micro-slit of less than 10 ?m  

Microsoft Academic Search

A technology for fabricating the micro-disk through the application of micro-EDM (micro electrode discharge machining) is proposed in this paper. Precisely controlling the tracking path of wire tool electrode during sparking, micro-disks with a variety of thickness can be formed on a metal raw pin. The process has been demonstrated by producing some products such as a parasol-shaped scanning probe

Chia-Lung Kuo; Jing-Dae Huang

2004-01-01

341

The Energy Quanta and the Entropy New Parameters for Identification of the Machining Processes  

Microsoft Academic Search

The contribution presents some new findings in search for a more comprehensive description of the machining processes, such as turning, milling and drilling. The experimentally determined power spectra of the input, transformation and output energy are used for computing the energy quanta and the entropy of the processes. It is shown, that the change of the entropy allows to explain

J. Peklenik; S. Dolinek

1995-01-01

342

Toward intelligent machining: hierarchical fuzzy control for the end milling process  

Microsoft Academic Search

The difficulties in implementing adaptive and other advanced control schemes in industrial machining processes have encouraged researchers to combine the utilization of one hierarchical level, a fuzzy control algorithm, and robust sensing systems. The main idea of this paper deals with self-regulating controllers (SRCs). The control signal's scaling factor (output scaling factor) is self-regulated during the control process, and it

R. E. Haber; C. R. Peres; A. Alique; S. Ros; C. Gonzalez; J. R. Alique

1998-01-01

343

Power metallurgy tool electrodes for electrical discharge machining  

Microsoft Academic Search

Electrodes in electrical discharge machining (EDM) can be compared with cutting tools in conventional machining. Tool performance is one of the important factors that determine the quality of the machined component. Due to the ease of manufacturing and control over the properties of electrodes, the powder metallurgy (P\\/M) technique has an advantage over other methods of electrode fabrication. P\\/M electrodes

M. P. Samuel; P. K. Philip

1997-01-01

344

Every intelligent ghost must contain a machine: an information-processing machine.  

E-print Network

. _________________________________________________________________________ Jane Austen's concept of information (Not Claude Shannon's) Aaron Sloman School of Computer Science.bham.ac.uk/research/projects/cogaff/misc/AREADME.html _________________________________________________________________________ Extracts From Jane Austen's Pride and Prejudice With thanks to Project Gutenburg: http://www.gutenberg.org/files/1342/1342-h/1342-h.htm Jane Austen knew a lot about human information processing as these snippets from

Sloman, Aaron

345

Electric discharge machining of AlSiC metal matrix composites using rotary tube electrode  

Microsoft Academic Search

The machining characteristics of SiC\\/6025 Al composite using rotary electro-discharge machining (EDM) with a tube electrode were investigated in this study. Brass was used as the electrode material to EDM SiC\\/6025 Al composites. Three observed values: material removal rate (MRR), electrode wear rate (EWR) and surface roughness (SR) are adopted to evaluate the machinability. Peak current, polarity, volume fraction of

B. Mohan; A. Rajadurai; K. G. Satyanarayana

2004-01-01

346

Rupture failure and mechanical strength of the electrode wire used in wire EDM  

Microsoft Academic Search

In the application of wire EDM, wire rupture is very troublesome and impedes further increase of cutting speed. Instead of the spark characteristics or the temperature distribution, the rupture mechanism and the mechanical strength of the wire are the focus of this investigation. Wire rupture is a mechanical failure in essence, although the process heat has significant influence on the

Y. F. Luo

1999-01-01

347

Surface Integrity of Hard Metal Parts Machined by WEDM  

NASA Astrophysics Data System (ADS)

Hard metal is characterised by having a extremely high hardness and high wear resistance, and those characteristics make difficult conventional machining. Electrical Discharge Machining (EDM) has become an attractive and feasible method for the manufacturing of precision hard metal tooling, and it is now an alternative to classical diamond grinding. This is due to the thermal nature of material removal mechanism in EDM, which is therefore independent on part hardness. This work pays attention to the analysis of surface integrity in wire EDM'ed hard metal parts. Damages on the machined surfaces have been characterised for different cutting regimes. Special attention has been paid to the heat affected zone, since it is in this zone where cracking mostly occurs. The study includes the analysis of the chemical composition of the affected layers. Additionally, the influence of successive trim cuts on surface roughness is addressed.

Plaza, S.; Izquierdo, B.; Sanchez, J. A.; Ortega, N.; Ramos, J. M.

2009-11-01

348

Cost-effective machining of brittle materials (glasses and ceramics) eliminating/minimizing the polishing process  

NASA Astrophysics Data System (ADS)

The disadvantages of traditional methods of edge grinding silicon wafers are discussed. With the industry's move to 300 mm format wafers, comes the pressure of environmental issues to minimize acid etch from the wafer process which is commonly used to improve surface finish and reduce sub surface damage. The recent work of Cranfield Precision in wafer edge processing is described, together with descriptions of a new grinding process and machine to eliminate grinding induced damage and minimize the polishing time.

Carlisle, Keith; Stocker, M. A.

1997-09-01

349

Optimization process planning using hybrid genetic algorithm and intelligent search for job shop machining  

Microsoft Academic Search

Optimization of process planning is considered as the key technology for computer-aided process planning which is a rather\\u000a complex and difficult procedure. A good process plan of a part is built up based on two elements: (1) the optimized sequence\\u000a of the operations of the part; and (2) the optimized selection of the machine, cutting tool and Tool Access Direction

Mojtaba Salehi; Ardeshir Bahreininejad

350

Direct processing of continuous fibers onto injection molding machines  

NASA Astrophysics Data System (ADS)

A new injection molding process 'DIF' (Direct Incorporation of Continuous Fibers) is proposed whereby roving strands are directly incorporated into the polymer melt by using a reciprocating-screw-plasticating unit. The DIF-technology offers the possibility to substitute the relatively expensive pultrusion process which is used to produce long fiber pellets. Furthermore it can be used as a fast and flexible R&D tool. In order to improve fiber dispersion with minimum fiber breakage a new mixing non-return-valve 'LFMR' (Long Fiber Mixing Ring) was developed based on the 'Twente Mixing Ring'; Its mixing capacity and influence on processing characteristics, fiber breakage and property profile of the injection molded parts is examined and compared to a general purpose non-return-valve of the ring type. The results of fundamental mechanical and physical property investigations are presented including dispersion of fiber clusters and bundles, fiber length distribution and fiber orientation.

Truckenmueller, F. M.

1993-06-01

351

Some Reflections on Medical Diagnosis by Electronic Data Processing Machines  

Microsoft Academic Search

The Vanderbilt University School of Medicine study of the feasibility of electronic data processing in medical diagnosis emphasizes a coordinated engineering and medical scientific effort. All needed technical modalities exist. Decisions have to be made about obtaining and encoding input patient information, size of memory, nature of access, the organization of data stored in it, the arithmetic of comparison, the

George R. Meneely

1960-01-01

352

A Butler process for resource sharing on Spice machines  

Microsoft Academic Search

A network of personal computers may contain a large amount of distributed computing resources. For a number of reasons it is desirable to share these resources, but sharing is complicated by issues of security and autonomy. A process known as the Butler addresses these problems and provides support for resource sharing. The Butler relies upon a capability-based accounting system called

Roger B. Dannenberg; Peter G. Hibbard

1985-01-01

353

Study on mechanism and process of ion beam machining on high-precision large optical surfaces  

NASA Astrophysics Data System (ADS)

Ion beam machining has become an important means adopted to high-precision large optical mirror processing. This study has conducted a bitmap-style model, calculation and analysis on low-energy Ar+ ion beam sputtering optical surface, based on Sigmund Theory and the CCOS principle. We have obtained the relationship of the removal function and the removal rate with major technological parameters of ion beam machining (e.g. dwell time, work distance, ion energy, etc.) also via orthogonal experiments of single point removal. Results indicated that the removal rate of amorphous SiO2 (fused silica) by Ar+ ions with 600~1200 electron volts increases with the increase of ion energy and dwell time at different extents, decreases exponentially with the increase in work distance. On the basis of computational analysis and experimental investigations, we optimized process conditions and further figured the plane mirror with the clear aperture of 130 millimeters, utilizing technologically optimized low-energy Ar+ ion beam machining. Eventually we obtained the high-precision figure shape with the post-machined surface roughness of 0.43~0.44 nm rms and the post-machined figure error of 1 nm rms.

Liang, Xiao; Gu, Yongqiang; Wang, Xiang; Ma, Zhanlong; Sui, Yongxin; Zheng, Jinjin

2014-08-01

354

Slow-Atom Electron EDM Experiment with Electric Field Quantization  

Microsoft Academic Search

Improving the electron electric dipole moment (e-EDM) upper limit has been a 40-year battle against systematic effects. Two new weapons in this battle are slow atoms and ground-state electric field quantization, both of which suppress motional magnetic field effects. They have been used effectively in a recently completed e-EDM experiment that is a prototype for a high-sensitivity Cs fountain e-EDM

Harvey Gould; Jason Amini; Charles Munger Jr.

2007-01-01

355

On the description of the bearing capacity of electro-discharge machined G.P Petropoulosa  

E-print Network

On the description of the bearing capacity of electro-discharge machined surfaces G.P Petropoulosa electro-discharge machining (EDM) is the most widely and successfully applied for the machining of various was performed on a HOSTEK SH-38GP (ZNC-P type) electro-discharge machine-tool with working voltage of 30V

Aristomenis, Antoniadis

356

Effect of processing parameters on surface finish for fused deposition machinable wax patterns  

NASA Technical Reports Server (NTRS)

This report presents a study on the effect of material processing parameters used in layer-by-layer material construction on the surface finish of a model to be used as an investment casting pattern. The data presented relate specifically to fused deposition modeling using a machinable wax.

Roberts, F. E., III

1995-01-01

357

Micro-machined micro ion source for flexible and concurrent process  

Microsoft Academic Search

In this paper a micro-machined micro ion source using B.K. (Barkhausen-Kurz) oscillation discharge to realize a high ion current is developed for flexible and concurrent MEMS processes. An ion beam with several muA from the micro ion source unit having phi1mmx4.37 mm discharge space was successfully generated.

S. Tamonoki; H. Kuwano; S. Nagasawa

2008-01-01

358

Process Control in Next-Generation Sewing Machines: A Project Overview  

Microsoft Academic Search

SYNOPSIS The sewing machine created in the XIX century has roughly remained unchanged in its basic technologies. Although a great range of mechanical and electronic technologies has boosted its development enormously, the process of sewing itself, however, although perfected in many aspects, has remained uncontrolled.Many of the phenomena occurring at high-speed sewing (up to 10000 stitches per minute) are still

Helder Carvalho; Joo L. Monteiro

359

Numerical magnetic field analysis and signal processing for fault diagnostics of electrical machines  

Microsoft Academic Search

Numerical magnetic field analysis is used for predicting the performance of an induction motor and a slip-ring generator having different faults implemented in their structure. Virtual measurement data provided by the numerical magnetic field analysis are analysed using modern signal processing techniques to get a reliable indication of the fault. Support vector machine based classification is applied to fault diagnostics.

S. Pyhnen; M. Negrea; P. Jover; A. Arkkio; H. Hytyniemi

2003-01-01

360

Optimal Selection of Machining Conditions in the Electrojet Drilling Process Using Hybrid NN-DF-GA Approach  

Microsoft Academic Search

This article presents a hybrid neural network, desirability function, and genetic algorithm (NN-DF-GA) approach for optimal selection of the input process parameters for optimizing the multiresponse parameters of the electrojet drilling (EJD) process. EJD is a promising nontraditional machining technique that is used for machining microholes (<1mm in diameter) in difficult-to-machine materials. The proposed approach first uses a back propagation

Mohan Sen; H. S. Shan

2006-01-01

361

CryoEDM: A cryogenic experiment to measure the neutron electric dipole moment  

NASA Astrophysics Data System (ADS)

CryoEDM is an experiment that aims to measure the electric dipole moment (EDM) of the neutron to a precision of 10 -28 e cm. A description of CryoEDM, the apparatus, technologies and commissioning is presented.

van der Grinten, M. G. D.; CryoEDM Collaboration; Balashov, S. N.; Francis, V.; Green, K.; Iaydjiev, P. S.; Ivanov, S. N.; Khazov, A.; Tucker, M. A. H.; Wark, D. L.; Davidson, A.; Hardiman, M.; Harris, P. G.; Katsika, K.; Pendlebury, J. M.; Peeters, S. J. M.; Shiers, D. B.; Smith, P.; Townsley, C.; Wardell, I.; Clarke, C.; Henry, S.; Kraus, H.; McCann, M.; Geltenbort, P.; Yoshiki, Y.

2009-12-01

362

Search for electron EDM with laser cooled radioactive atom  

NASA Astrophysics Data System (ADS)

The permanent electric dipole moment (EDM) of the elementary particle has the sensitivity to the CP violation in the theories beyond the standard model (SM). The search for the EDM constitutes the stringent test to discriminate between the SM and beyond it. We plan to perform the electron EDM search by using the laser cooled francium (Fr) atom which has the largest enhancement factor of the electron EDM in the alkali atoms. In this paper, the present status of the laser cooled Fr factory that is being constructed at Cyclotron and Radioisotope Center (CYRIC), Tohoku University are reported.

Inoue, T.; Arikawa, H.; Ezure, S.; Harada, K.; Hayamizu, T.; Ishikawa, T.; Itoh, M.; Kato, T.; Kawamura, H.; Nataraj, H. S.; Sato, T.; Aoki, T.; Furukawa, T.; Hatakeyama, A.; Hatanaka, K.; Imai, K.; Murakami, T.; Shimizu, Y.; Wakasa, T.; Yoshida, H. P.; Sakemi, Y.

2013-05-01

363

Improved Measurement of the Electron EDM  

NASA Astrophysics Data System (ADS)

The electron is predicted to be slightly aspheric,ootnotetextI. B. Khriplovich, S. K. Lamoreaux, CP Violation Without Strangeness (Springer, New York, 1997). though no experiment has ever observed this deviation. Comparing the measured and predicted shape provides a powerful test of the standard model of particle physics. The shape is also intimately related to one of the largest outstanding questions in cosmology: why is the universe almost entirely devoid of antimatter? The electron's shape can be characterised by its electric dipole moment (EDM), de, which measures the deviation of its electric interactions from purely spherical. According to the standard model, this EDM is de 10-38 e.cm -- some eleven orders of magnitude below the current experimental limit. Most extensions to the standard model predict much larger values, potentially accessible to measurement.ootnotetextE. D. Commins, Electric dipole moments of leptons, in Advances in Atomic, Molecular, and Optical Physics, Vol. 40, B. Bederson and H.Walther (Eds.), Academic Press, New York, pp. 1-56 (1999). Hence, the search for the electron EDM is a search for physics beyond the standard model. Moreover, a non-zero breaks time-reversal symmetry which, in many models of particle physics, is equivalent to breaking the symmetry between matter and antimatter, known as CP symmetry. New CP-breaking physics is thought to be needed to explain the existence of a material universe.ootnotetextA. D. Sakharov, Violation of CP invariance, C asymmetry, and baryon asymmetry of the universe, Pis'ma ZhETF 5, 32 (1967). *Sov. Phys. JETP Lett. 5, 24 (1967).] We have used cold, polar molecules to measure the electron EDM, obtaining the result de= (-2.4 5.7stat1.5syst) x10-28 e.cm. We set a new upper limit of with 90% confidence. Our result, consistent with zero, indicates that the electron is spherical at this improved level of precision. Our measurement, of atto-eV energy shifts in a molecule, probes new physics at the tera-eV energy scale. Many extensions to the standard model, such as the minimal supersymmetric standard model, naturally predict large EDMs and our measurement places significant constraints on the parameters of these theories.ootnotetextE. D. Commins and D. DeMille, ``The electric dipole moment of the electron,'' Chapter 14 in Lepton Dipole Moments Eds. B. L. Roberts and W. J. Marciano, (World Scientific, Singapore 2010).

Hinds, E. A.

2011-06-01

364

Batch mode micro-electro-discharge machining  

Microsoft Academic Search

This paper describes a micro-electro-discharge machining (micro-EDM) technique that uses electrode arrays to achieve high parallelism and throughput in the machining. It explores constraints in the fabrication and usage of high aspect ratio LIGA-fabricated electrode arrays, as well as the limits imposed by the pulse discharge circuits on machining rates. An array of 400 Cu electrodes with 20 ?m diameter

K. Takahata; Y. B. Gianchandani

2002-01-01

365

Etching process for improving the strength of a laser-machined silicon-based ceramic article  

DOEpatents

A process for improving the strength of laser-machined articles formed of a silicon-based ceramic material such as silicon nitride, in which the laser-machined surface is immersed in an etching solution of hydrofluoric acid and nitric acid for a duration sufficient to remove substantially all of a silicon film residue on the surface but insufficient to allow the solution to unduly attack the grain boundaries of the underlying silicon nitride substrate. This effectively removes the silicon film as a source of cracks that otherwise could propagate downwardly into the silicon nitride substrate and significantly reduce its strength.

Copley, Stephen M. (Palos Verdes, CA); Tao, Hongyi (Covina, CA); Todd-Copley, Judith A. (Palos Verdes, CA)

1991-01-01

366

Etching process for improving the strength of a laser-machined silicon-based ceramic article  

DOEpatents

A process is disclosed for improving the strength of laser-machined articles formed of a silicon-based ceramic material such as silicon nitride, in which the laser-machined surface is immersed in an etching solution of hydrofluoric acid and nitric acid for a duration sufficient to remove substantially all of a silicon film residue on the surface but insufficient to allow the solution to unduly attack the grain boundaries of the underlying silicon nitride substrate. This effectively removes the silicon film as a source of cracks that otherwise could propagate downwardly into the silicon nitride substrate and significantly reduce its strength. 1 figure.

Copley, S.M.; Tao, H.; Todd-Copley, J.A.

1991-06-11

367

Principles of image processing in machine vision systems for the color analysis of minerals  

NASA Astrophysics Data System (ADS)

At the moment color sorting method is one of promising methods of mineral raw materials enrichment. This method is based on registration of color differences between images of analyzed objects. As is generally known the problem with delimitation of close color tints when sorting low-contrast minerals is one of the main disadvantages of color sorting method. It is can be related with wrong choice of a color model and incomplete image processing in machine vision system for realizing color sorting algorithm. Another problem is a necessity of image processing features reconfiguration when changing the type of analyzed minerals. This is due to the fact that optical properties of mineral samples vary from one mineral deposit to another. Therefore searching for values of image processing features is non-trivial task. And this task doesn't always have an acceptable solution. In addition there are no uniform guidelines for determining criteria of mineral samples separation. It is assumed that the process of image processing features reconfiguration had to be made by machine learning. But in practice it's carried out by adjusting the operating parameters which are satisfactory for one specific enrichment task. This approach usually leads to the fact that machine vision system unable to estimate rapidly the concentration rate of analyzed mineral ore by using color sorting method. This paper presents the results of research aimed at addressing mentioned shortcomings in image processing organization for machine vision systems which are used to color sorting of mineral samples. The principles of color analysis for low-contrast minerals by using machine vision systems are also studied. In addition, a special processing algorithm for color images of mineral samples is developed. Mentioned algorithm allows you to determine automatically the criteria of mineral samples separation based on an analysis of representative mineral samples. Experimental studies of the proposed algorithm were performed using samples of gold and copper-nickel ores. And obtained results confirmed its efficiency with respect to mineral objects. The research results will allow: expanding the use of the color sorting method in the field of mineral raw materials enrichment; facilitating the search for values of image processing features for machine vision systems which are used to the color analysis of minerals; reducing the time required for reconfiguration of image processing features when changing the type of analyzed minerals; realizing the process of rapid estimating the concentration rate of analyzed mineral ore by using color sorting method.

Petukhova, Daria B.; Gorbunova, Elena V.; Chertov, Aleksandr N.; Korotaev, Valery V.

2014-09-01

368

Accurate Performance Models of Parallel Low Level Image Processing Operations Based on a Simple Abstract Machine  

Microsoft Academic Search

Abstract: MachineF.J. Seinstra and D. KoelmaFaculty of ScienceUniversity of AmsterdamThe NetherlandsThis paper presents performance models for accurate prediction of the executiontime of a large set of image processing operations, executed on distributed memoryMIMD-style parallel hardware. The models incorporate a strict separation betweenthe two (essentially unrelated) aspects of parallel execution: (1) sequential computationand (2) inter-process communication. The model parameters are ...

F. Seinstra; D. Koelma

2000-01-01

369

Application of machine learning and expert systems to Statistical Process Control (SPC) chart interpretation  

NASA Technical Reports Server (NTRS)

Statistical Process Control (SPC) charts are one of several tools used in quality control. Other tools include flow charts, histograms, cause and effect diagrams, check sheets, Pareto diagrams, graphs, and scatter diagrams. A control chart is simply a graph which indicates process variation over time. The purpose of drawing a control chart is to detect any changes in the process signalled by abnormal points or patterns on the graph. The Artificial Intelligence Support Center (AISC) of the Acquisition Logistics Division has developed a hybrid machine learning expert system prototype which automates the process of constructing and interpreting control charts.

Shewhart, Mark

1991-01-01

370

1nEDM collaboration Progress Report, February 2004  

E-print Network

assembling and coating by permalloy #12;7nEDM collaboration Progress Report, February 2004 Magnetic shielding, design and manufacturing Results of 2003: 1. A new magnetic shielding has been prepared in order to test;2nEDM collaboration Progress Report, February 2004 Content 1. Magnetic shielding, design

Titov, Anatoly

371

Recent Results from the PbO Electron EDM Experiment  

Microsoft Academic Search

Observation of an electric dipole moment (EDM) of the electron would imply CP violation beyond the Standard Model. This experiment searches for the electron EDM using a metastable state of the PbO molecule. Several unique properties of this state, including closely spaced levels of opposite parity and a long coherence time, make it suitable for use in a vapor cell,

Paul Hamilton; Hunter Smith; David Demille

2009-01-01

372

Recent Results from the PbO Electron EDM Experiment  

Microsoft Academic Search

We are currently taking the first data in our search for a permanent electric dipole moment (EDM) of the electron using a lead oxide (PbO) vapor cell. The existence of an EDM would imply physics beyond the standard model. We will present the current results and discuss limits on our statistical sensitivity as well as prospects for near and far

Paul Hamilton; Sarah Bickman; Yong Jiang; Hunter Smith; Amar Vutha; David Demille

2008-01-01

373

Recent Results from the PbO Electron EDM Experiment  

Microsoft Academic Search

Observation of an electric dipole moment (EDM) of the electron would imply CP violation beyond the Standard Model. This experiment searches for the electron EDM using a metastable state of the PbO molecule. Several unique properties of this state, including closely spaced levels of opposite parity and a long coherence time, make it suitable for use in a vapor cell,

Paul Hamilton; Emil Kirilov; Hunter Smith; David Demille

2010-01-01

374

A Measurement of the Electron edm using GdIG  

Microsoft Academic Search

A measurement of the electron electric dipole moment (edm) using gadolinium iron garnet (GdIG) will be discussed. GdIG is a soft magnetic dielectric with a strong temperature -dependent contribution to its magnetization from paramagnetic gadolinium ions. Near liquid nitrogen temperatures, the Gd spins become substantially aligned when the sample is placed in a strong magnetic field. An edm of the

Larry Hunter; Noah Charney; Joel Gordon; Steve Peck; Oliver Elliott; Margaret McKeon; Steve Lamoreaux

2003-01-01

375

Optimization process planning using hybrid genetic algorithm and intelligent search for job shop machining  

PubMed Central

Optimization of process planning is considered as the key technology for computer-aided process planning which is a rather complex and difficult procedure. A good process plan of a part is built up based on two elements: (1) the optimized sequence of the operations of the part; and (2) the optimized selection of the machine, cutting tool and Tool Access Direction (TAD) for each operation. In the present work, the process planning is divided into preliminary planning, and secondary/detailed planning. In the preliminary stage, based on the analysis of order and clustering constraints as a compulsive constraint aggregation in operation sequencing and using an intelligent searching strategy, the feasible sequences are generated. Then, in the detailed planning stage, using the genetic algorithm which prunes the initial feasible sequences, the optimized operation sequence and the optimized selection of the machine, cutting tool and TAD for each operation based on optimization constraints as an additive constraint aggregation are obtained. The main contribution of this work is the optimization of sequence of the operations of the part, and optimization of machine selection, cutting tool and TAD for each operation using the intelligent search and genetic algorithm simultaneously. PMID:21845020

Salehi, Mojtaba

2010-01-01

376

Selection of Wire Electrical Discharge Machining Process Parameters on Stainless Steel AISI Grade-304 using Design of Experiments Approach  

NASA Astrophysics Data System (ADS)

Wire electrical discharge machining (WEDM) is a specialized thermal machining process capable of accurately machining parts of hard materials with complex shapes. Parts having sharp edges that pose difficulties to be machined by the main stream machining processes can be easily machined by WEDM process. Design of Experiments approach (DOE) has been reported in this work for stainless steel AISI grade-304 which is used in cryogenic vessels, evaporators, hospital surgical equipment, marine equipment, fasteners, nuclear vessels, feed water tubing, valves, refrigeration equipment, etc., is machined by WEDM with brass wire electrode. The DOE method is used to formulate the experimental layout, to analyze the effect of each parameter on the machining characteristics, and to predict the optimal choice for each WEDM parameter such as voltage, pulse ON, pulse OFF and wire feed. It is found that these parameters have a significant influence on machining characteristic such as metal removal rate (MRR), kerf width and surface roughness (SR). The analysis of the DOE reveals that, in general the pulse ON time significantly affects the kerf width and the wire feed rate affects SR, while, the input voltage mainly affects the MRR.

Lingadurai, K.; Nagasivamuni, B.; Muthu Kamatchi, M.; Palavesam, J.

2012-06-01

377

Microstructure, Morphology, and Nanomechanical Properties Near Fine Holes Produced by Electro-Discharge Machining  

NASA Astrophysics Data System (ADS)

Fine holes in metal alloys are employed for many important technological purposes, including cooling and the precise atomization of liquids. For example, they play an important role in the metering and delivery of fuel to the combustion chambers in energy-efficient, low-emission diesel engines. Electro-discharge machining (EDM) is one process employed to produce such holes. Since the hole shape and bore morphology can affect fluid flow, and holes also represent structural discontinuities in the tips of the spray nozzles, it is important to understand the microstructures adjacent to these holes, the features of the hole walls, and the nanomechanical properties of the material that was in some manner altered by the EDM hole-making process. Several techniques were used to characterize the structure and properties of spray-holes in a commercial injector nozzle. These include scanning electron microscopy, cross sectioning and metallographic etching, bore surface roughness measurements by optical interferometry, scanning electron microscopy, and transmission electron microscopy of recast EDM layers extracted with the help of a focused ion beam.

Blau, P. J.; Howe, J. Y.; Coffey, D. W.; Trejo, R. M.; Kenik, E. D.; Jolly, B. C.; Yang, N.

2012-08-01

378

Microstructure, Morphology, and Nanomechanical Properties Near Fine Holes Produced by Electro-Discharge Machining  

SciTech Connect

Fine holes in metal alloys are employed for many important technological purposes, including cooling and the precise atomization of liquids. For example, they play an important role in the metering and delivery of fuel to the combustion chambers in energy-efficient, low-emissions diesel engines. Electro-discharge machining (EDM) is one process employed to produce such holes. Since the hole shape and bore morphology can affect fluid flow, and holes also represent structural discontinuities in the tips of the spray nozzles, it is important to understand the microstructures adjacent to these holes, the features of the hole walls, and the nanomechanical properties of the material that was in some manner altered by the EDM hole-making process. Several techniques were used to characterize the structure and properties of spray-holes in a commercial injector nozzle. These include scanning electron microscopy, cross-sectioning and metallographic etching, bore surface roughness measurements by optical interferometry, scanning electron microscopy, and transmission electron microscopy of recast EDM layers extracted with the help of a focused ion beam.

Blau, Peter Julian [ORNL; Howe, Jane Y [ORNL; Coffey, Dorothy W [ORNL; Trejo, Rosa M [ORNL; Kenik, Edward A [ORNL; Jolly, Brian C [ORNL; Yang, Nan [Caterpillar Inc.

2012-01-01

379

3D Machine Vision and Additive Manufacturing: Concurrent Product and Process Development  

NASA Astrophysics Data System (ADS)

The manufacturing environment rapidly changes in turbulence fashion. Digital manufacturing (DM) plays a significant role and one of the key strategies in setting up vision and strategic planning toward the knowledge based manufacturing. An approach of combining 3D machine vision (3D-MV) and an Additive Manufacturing (AM) may finally be finding its niche in manufacturing. This paper briefly overviews the integration of the 3D machine vision and AM in concurrent product and process development, the challenges and opportunities, the implementation of the 3D-MV and AM at POLMAN Bandung in accelerating product design and process development, and discusses a direct deployment of this approach on a real case from our industrial partners that have placed this as one of the very important and strategic approach in research as well as product/prototype development. The strategic aspects and needs of this combination approach in research, design and development are main concerns of the presentation.

Ilyas, Ismet P.

2013-06-01

380

Feature Extraction and Assessment Using Wavelet Packets for Monitoring of Machining Processes  

NASA Astrophysics Data System (ADS)

Monitoring of machining processes is a classic and yet unsolved problem in manufacturing engineering. This paper introduces a new method of feature extraction and feature assessment using a wavelet packet transform for monitoring of machining processes. First, the principles of wavelet transforms are briefly described by comparing to the Fourier transform, followed by a discussion on the properties of wavelet transforms and a special wavelet transform algorithm: the wavelet packet transform. Next, based on the wavelet packet transform and signal reconstruction, a new feature extraction method is introduced. To assess the effectiveness of the selected features in both time and frequency domains, four criteria are proposed. Accordingly an automatic feature extraction procedure is developed. The proposed method is tested using two practical examples: chatter monitoring in turning and tool wear monitoring in drilling. Experimental results show that the proposed method is very effective.

Wu, Ya; Du, R.

1996-01-01

381

Optimization of Machining Process Parameters for Surface Roughness of Al-Composites  

NASA Astrophysics Data System (ADS)

Metal matrix composites (MMCs) have become a leading material among the various types of composite materials for different applications due to their excellent engineering properties. Among the various types of composites materials, aluminum MMCs have received considerable attention in automobile and aerospace applications. These materials are known as the difficult-to-machine materials because of the hardness and abrasive nature of reinforcement element-like silicon carbide particles. In the present investigation Al-SiC composite was produced by stir casting process. The Brinell hardness of the alloy after SiC addition had increased from 74 2 to 95 5 respectively. The composite was machined using CNC turning center under different machining parameters such as cutting speed (S), feed rate (F), depth of cut (D) and nose radius (R). The effect of machining parameters on surface roughness (Ra) was studied using response surface methodology. Face centered composite design with three levels of each factor was used for surface roughness study of the developed composite. A response surface model for surface roughness was developed in terms of main factors (S, F, D and R) and their significant interactions (SD, SR, FD and FR). The developed model was validated by conducting experiments under different conditions. Further the model was optimized for minimum surface roughness. An error of 3-7 % was observed in the modeled and experimental results. Further, it was fond that the surface roughness of Al-alloy at optimum conditions is lower than that of Al-SiC composite.

Sharma, S.

2013-10-01

382

Interpreting statistical process control (SPC) charts using machine learning and expert system techniques  

Microsoft Academic Search

Statistical process control (SPC) charts are one of several tools used in quality control. The SPC quality control tool has been under-utilized due to the lack of experienced personnel able to identify and interpret patterns within the control charts. The Special Projects Office of the Center for Supportability and Technology Insertion (CSTI) has developed a hybrid machine-learning and expert-system software

Mark Shewhart; Wright Patterson AFB

1992-01-01

383

Kinematic Analysis of Cpm Machine Supporting to Rehabilitation Process after Surgical Knee Arthroscopy and Arthroplasty  

NASA Astrophysics Data System (ADS)

Existing commercial solutions of the CPM (Continuous Passive Motion) machines are described in the paper. Based on the analysis of existing solutions we present our conceptual solution to support the process of rehabilitation of the knee joint which is necessary after arthroscopic surgery. For a given novel structure we analyze and present proprietary algorithms and the computer application to simulate the operation of our PCM device. In addition, we suggest directions for further research.

Trochimczuk, R.; Ku?mierowski, T.

2014-11-01

384

EMAT weld inspection and weld machine diagnostic system for continuous coil processing lines  

NASA Astrophysics Data System (ADS)

Weld breaks of steel coil during cold rolling and continuous pickling operations are a significant source of lost productivity and product yield. Babcock and Wilcox Innerspec Technologies has developed a weld process control system which monitors the key variables of the welding process and determines the quality of the welds generated by flash butt welding equipment. This system is known as the Temate 2000 Automated Flash Butt Weld Inspection and Weld Machine Diagnostic System. The Temate 2000 system utilizes electro- magnetic acoustic transducer (EMAT) technology as the basis for performing on-line, real-time, nondestructive weld quality evaluation. This technique accurately detects voids, laps, misalignment and over/under trim conditions in the weld. Results of the EMAT weld inspection are immediately presented to the weld machine operator for disposition. Welding process variables such as voltage, current, platen movements and upset pressures are monitored and collected with the high speed data acquisition system. This data is processed and presented in real-time display to indicate useful welding process information such as platen crabbing, upset force, peak upset current, and many others. Alarming for each variable is provided and allows detailed maintenance reports and summary information to be generated. All weld quality and process parameter data are stored, traceable to each unique weld, and available for post process evaluation. Installation of the Temate 2000 system in a major flat rolled steel mill has contributed to near elimination of weld breakage and increased productivity at this facility.

Latham, Wayne M.; MacLauchlan, Daniel T.; Geier, Dan P.; Lang, Dennis D.

1996-11-01

385

Processing and properties of ultra-high temperature ceramics for space applications  

Microsoft Academic Search

The processing and the properties of two ultra-high temperature ceramics (UHTCs) designed for the manufacturing of aerospace sharp-shaped hot-structures are presented, along with the results obtained in the electrical discharge machining (EDM) of these UHTCs into sharp hot-structure components.The powder mixtures in the (ZrB2SiC)-based systems were brought to full density by hot-pressing. The hot-pressed bodies were characterized by fine and

F. Monteverde; A. Bellosi; Luigi Scatteia

2008-01-01

386

Thermal stresses due to electrical discharge machining  

Microsoft Academic Search

The high temperature gradients generated at the gap during electrical discharge machining (EDM) result in large localized thermal stresses in a small heat-affected zone. These thermal stresses can lead to micro-cracks, decrease in strength and fatigue life and possibly catastrophic failure. A finite element model has been developed to estimate the temperature field and thermal stresses due to Gaussian distributed

Vinod Yadav; Vijay K. Jain; Prakash M. Dixit

2002-01-01

387

Post-cast EDM method for reducing the thickness of a turbine nozzle wall  

DOEpatents

A post-cast EDM process is used to remove material from the interior surface of a nozzle vane cavity of a turbine. A thin electrode is passed through the cavity between opposite ends of the nozzle vane and displaced along the interior nozzle wall to remove the material along a predetermined path, thus reducing the thickness of the wall between the cavity and the external surface of the nozzle. In another form, an EDM process employing a profile as an electrode is disposed in the cavity and advanced against the wall to remove material from the wall until the final wall thickness is achieved, with the interior wall surface being complementary to the profile surface.

Jones, Raymond Joseph (Duanesburg, NY); Bojappa, Parvangada Ganapathy (Schenectady, NY); Kirkpatrick, Francis Lawrence (Galway, NY); Schotsch, Margaret Jones (Clifton Park, NY); Rajan, Rajiv (Guilderland, NY); Wei, Bin (Mechanicville, NY)

2002-01-01

388

New Fabrication Process for Monolithic Probes with Integrated Heaters for Nanothermal Machining  

NASA Astrophysics Data System (ADS)

In this study, we developed a new fabrication process for a micromachined probe. The microprobe comprised a microcantilever, a nanotip and a supporting substrate, which are monolithically made of single-crystal silicon. The fabrication process started with a bilayer silicon wafer made up of a 20-?m-thick epitaxial Si layer with strong boron doping and a 400-?m-thick bulk Si substrate. The tip with a radius of curvature of 50 nm was formed by anisotropic etching followed by oxidation sharpening. Then a cantilever beam was released by the back etching of an etch-stop Si layer. The spring constants of cantilevers ranging from 0.03 to 0.4 N/m were determined by finite element analysis (FEA), static measurement using an atomic force microscope (AFM) system and dynamic measurement using a laser Doppler vibrometer (LDV) system. Most importantly, Youngs modulus of thin-film materials could be confirmed using these methods. The developed probe was also equipped with a Pt heater to apply it to thermal machining on poly(methyl methacrylate) (PMMA) substrates. The cantilever tip was heated to above 120C, and the successful machining of a cavity and a submicron-scale straight line was demonstrated. The development of the probes could be crucial for the submicron-scale machining of plastic materials.

Chiou, Chi-Han; Chang, Shang-Jen; Lee, Gwo-Bin; Lee, Huei-Huang

2006-01-01

389

ELECTROMAGNETIC EMISSIONS TO 60 GHZ FROM A BPT4000 EDM HALL THRUSTER  

Microsoft Academic Search

Radiated electric and magnetic fields, static magnetic fields, discharge oscillations, and conducted emissions were measured from a BPT-4000 Engineering Development Model (EDM) Hall thruster operating with a flight-like power processing unit (PPU) and xenon flow controller. Measurements were made at four operating conditions: a power of 3.0 kW with 300 V discharge voltage, 3.0 kW at 400 V, 4.5 kW

Edward J. Beiting; James E. Pollard; Vadim Khayms; Lance Werthman

390

Improved cemented carbide properties after wire-EDM by pulse shaping  

Microsoft Academic Search

In many applications the wire-EDM of cemented carbides (WEDM) (WC(TiC)Co) is restricted by the basic properties of this family of materials. Therefore, this research was aimed at developing an optimal process energy source that produces improved material properties after WEDM.The studies showed that it is important to use the correct parameter selection for main-cut and post-cut. Deterioration in the material

H. Juhr; H.-P. Schulze; G. Wollenberg; K. Knanz

2004-01-01

391

An energy-distribution strategy in fast-cutting wire EDM  

Microsoft Academic Search

The technical requirements of fast-cutting wire EDM are revealed in this paper. In addition to high input pulse energy, fast cutting (cutting speed > 200 mm2\\/min) without damaging the electrode wire needs a high energy efficiency for maintaining a stable fast-cutting process and moderate wire temperature. Based on a synthesis of experimental results and pulse energy analysis, an energy-distribution diagram

Y. F. Luo

1995-01-01

392

Progress toward an EDM measurement in 225Ra  

NASA Astrophysics Data System (ADS)

Permanent electric dipole moments (EDMs) in atoms or molecules are a signature of time-reversal and parity violation and represent an important window onto physics beyond the Standard Model. We are developing a next generation EDM search based on laser-cooled and trapped 225Ra atoms. Due to octupole deformation of the nucleus, 225Ra is predicted to be two to three orders of magnitude more sensitive to T-violating interactions than 199Hg, which currently sets the most stringent limits in the nuclear sector. We will discuss progress toward realizing a first EDM measurement for 225Ra.

Holt, R. J.; Ahmad, I.; Bailey, K.; Graner, B.; Greene, J. P.; Korsch, W.; Lu, Z.-T.; Mueller, P.; O'Connor, T. P.; Sulai, I. A.; Trimble, W. L.

2010-11-01

393

Search for a permanent EDM using laser cooled radioactive atom  

NASA Astrophysics Data System (ADS)

The search for the electric-dipole moment (EDM) of laser-cooled francium (Fr) atoms could lead to a measurement for the electron EDM. It is predicted that the electron EDM would be enhanced by approximately three orders of magnitude in heavy atoms such as Fr. Laser-cooling and trapping techniques are expected to suppress statistical and systematic errors in precision measurements. The magneto-optical trap was achieved using stable rubidium in a developing factory of laser-cooled radioactive atoms. In light of the results from the rubidium experiments, we found that an upgrade of each apparatus is preferred for Fr trapping.

Kawamura, Hirokazu; Ando, S.; Aoki, T.; Arikawa, H.; Ezure, S.; Harada, K.; Hayamizu, T.; Inoue, T.; Ishikawa, T.; Itoh, M.; Kato, K.; Kato, T.; Nataraj, H. S.; Sato, T.; Uchiyama, A.; Aoki, T.; Furukawa, T.; Hatakeyama, A.; Hatanaka, K.; Imai, K.; Murakami, T.; Shimizu, Y.; Wakasa, T.; Yoshida, H. P.; Sakemi, Y.

2014-03-01

394

MUON EDM EXPERIMENT USING STAGE II OF THE NEUTRINO FACTORY.  

SciTech Connect

During the second stage of a future neutrino factory unprecedented numbers of bunched muons will become available. The cooled medium-energy muon beam could be used for a high sensitivity search for an electric dipole moment (EDM) of the muon with a sensitivity better than 10{sup -24}e {center_dot} cm. This will make the sensitivity of the EDM experiment to non-standard physics competitive and in many models more sensitive than the present limits on edms of the electron and nucleons. The experimental design exploits the strong motional electric field sensed by relativistic particles in a magnetic storage ring.

FERNOW,R.C.; GALLARDO,J.C.; MORSE,W.M.; SEMERTZIDIS,Y.K.

2002-07-01

395

Optimization of laser machining process for the preparation of photomasks, and its application to microsystems fabrication  

NASA Astrophysics Data System (ADS)

Conventional photolithography normally utilizes a photomask for patterning light onto a chemical resist film. Therefore, the accuracy of microfabrication is highly dependent on the accuracy of the photomasks. Fabrication of hard masks involves the use of expensive laser pattern generators and other sophisticated machines using very high-precision stages and the necessary control instrumentation; therefore, an inexpensive strategy is highly necessary for laboratory-level fabrication. As this technology is primarily based on raster scanning of a laser beam, the mask making as such becomes a low-throughput process. A strategy of high-throughput manufacturing of hard masks with laser micromachining using a one-step exposure process of a chromated glass slide through a micromachined aluminum shadow mask is proposed. The features that are finally embedded in the mask are highly demagnified and well focused. Optimization of the laser machining process is carried out by considering all processing parameters. The features are characterized using an optical microscope, a scanning electron microscope, and a self-developed image analysis code. Geometrical methods are used to estimate the average edge roughness and feature size. We have also validated the usage of these masks by performing microfabrication on films made of photoresist.

Kumar, Avinash; Gupta, Ankur; Kant, Rishi; Akhtar, Syed Nadeem; Tiwari, Nachiketa; Ramkumar, Janakrajan; Bhattacharya, Shantanu

2013-10-01

396

New results from the YbF EDM experiment  

NASA Astrophysics Data System (ADS)

The standard model of particle physics predicts that, due to time reversal symmetry, the permanent electric dipole moment (EDM) of the electron is very nearly zero. Many extensions to the standard model predict an electron EDM or other T-violating effects just below current experimental limits, thus there is great interest in new experiments and in improving current experimental precision. I will discuss our recent measurement of the electron EDM using YbF molecules. YbF is particularly sensitive to the electron EDM. This experiment uses a form of laser-radiofrequency double resonance spectroscopy to search for very small energy differences between hyperfine levels in a strong electric field. In addition to describing the experimental and analysis techniques, I will give an overview of the techniques we use to check for systematic errors. I will also describe planned improvements to the experiment which promise several orders of magnitude improvement in sensitivity.

Sauer, B. E.

2013-04-01

397

EDM-DEDM and protein crystal structure solution.  

PubMed

Electron-density modification (EDM) procedures are the classical tool for driving model phases closer to those of the target structure. They are often combined with automated model-building programs to provide a correct protein model. The task is not always performed, mostly because of the large initial phase error. A recently proposed procedure combined EDM with DEDM (difference electron-density modification); the method was applied to the refinement of phases obtained by molecular replacement, ab initio or SAD phasing [Caliandro, Carrozzini, Cascarano, Giacovazzo, Mazzone & Siliqi (2009), Acta Cryst. D65, 249-256] and was more effective in improving phases than EDM alone. In this paper, a novel fully automated protocol for protein structure refinement based on the iterative application of automated model-building programs combined with the additional power derived from the EDM-DEDM algorithm is presented. The cyclic procedure was successfully tested on challenging cases for which all other approaches had failed. PMID:19390153

Caliandro, Rocco; Carrozzini, Benedetta; Cascarano, Giovanni Luca; Giacovazzo, Carmelo; Mazzone, Anna Maria; Siliqi, Dritan

2009-05-01

398

Machining Characteristics and Optimization of Machining Parameters of SKH 57 High-Speed Steel Using Electrical-Discharge Machining Based on Taguchi Method  

Microsoft Academic Search

The effects of the machining parameters in electrical-discharge machining (EDM) on the machining characteristics of SKH 57 high-speed steel were investigated. A well-designed experimental scheme was used to reduce the total number of experiments. Parts of the experiment were conducted with the L18 orthogonal array based on the Taguchi method. Moreover, the signal-to-noise ratios associated with the observed values in

Yan-Cherng Lin; Chao-Hsu Cheng; Bo-Lin Su; Lih-Ren Hwang

2006-01-01

399

Electrical Engineering Faculty Tulay Adali, Ph.D., North Carolina State University: Statistical signal processing, machine learning for signal  

E-print Network

-scale integrated sensor systems, RF-photonic and optical switching devices Anthony Johnson, Ph.D., City College: Statistical signal processing, machine learning for signal processing, adaptive signal processing, biomedical: Optical communications, non-linear optics, lasers, bio-photonics Chein-I Chang, Ph.D., University

Adali, Tulay

400

Progress towards an atomic EDM measurement of Ra-225  

NASA Astrophysics Data System (ADS)

We are searching for the permanent electric dipole moment (EDM) of the Radium-225 nucleus. A nonzero nuclear EDM is a signature of CP- and T-violating interactions within nuclei. Currently, the best experimental limits on these interactions are derived from EDM measurements of Mercury-199. The Ra-225 radioisotope (half-life of 15 days) is an attractive alternative because, due to its peculiar shape (nuclear octupole deformation), it is predicted to be a few hundred to a few thousand times more sensitive to these types of interactions than Hg-199. In our measurement scheme, Ra atoms are first laser cooled and trapped in a magneto-optical trap and then transferred to an optical dipole trap (ODT), both of which have already been demonstrated. The ODT is moved to a magnetically-shielded science chamber, and then the atoms are transferred to a perpendicular ODT in which the EDM will be measured. Transfer efficiencies between the two ODT's as high as 60% have been demonstrated. We will report on progress towards measurements of atomic properties necessary for the EDM search and the EDM search itself. Research supported by DOE, Office of Nuclear Physics, contract No. DE-AC02-06CH11357.

Parker, Richard; Bailey, Kevin; Dietrich, Matthew; Greene, John; Holt, Roy; Kalita, Mukut; Korsch, Wolfgang; Lu, Zheng-Tian; Mueller, Peter; O'Conner, Tom; Singh, Jaideep

2012-03-01

401

C. E. Rasmussen & C. K. I. Williams, Gaussian Processes for Machine Learning, the MIT Press, 2006, ISBN 026218253X. c 2006 Massachusetts Institute of Technology. www.GaussianProcess.org/gpml  

E-print Network

Glymour, and Richard Scheines Principles of Data Mining, David Hand, Heikki Mannila, and Padhraic SmythC. E. Rasmussen & C. K. I. Williams, Gaussian Processes for Machine Learning, the MIT Press, 2006 Processes for Machine Learning #12;C. E. Rasmussen & C. K. I. Williams, Gaussian Processes for Machine

Henderson, Thomas C.

402

Arabidopsis EDM2 promotes IBM1 distal polyadenylation and regulates genome DNA methylation patterns  

PubMed Central

DNA methylation is important for the silencing of transposons and other repetitive elements in many higher eukaryotes. However, plant and mammalian genomes have evolved to contain repetitive elements near or inside their genes. How these genes are kept from being silenced by DNA methylation is not well understood. A forward genetics screen led to the identification of the putative chromatin regulator Enhanced Downy Mildew 2 (EDM2) as a cellular antisilencing factor and regulator of genome DNA methylation patterns. EDM2 contains a composite Plant Homeo Domain that recognizes both active and repressive histone methylation marks at the intronic repeat elements in genes such as the Histone 3 lysine 9 demethylase gene Increase in BONSAI Methylation 1 (IBM1) and is necessary for maintaining the expression of these genes by promoting mRNA distal polyadenylation. Because of its role in maintaining IBM1 expression, EDM2 is required for preventing CHG methylation in the bodies of thousands of genes. Our results thus increase the understanding of antisilencing, genome methylation patterns, and regulation of alternative RNA processing by intronic heterochromatin. PMID:24248388

Lei, Mingguang; La, Honggui; Lu, Kun; Wang, Pengcheng; Miki, Daisuke; Ren, Zhizhong; Duan, Cheng-Guo; Wang, Xingang; Tang, Kai; Zeng, Liang; Yang, Lan; Zhang, Heng; Nie, Wenfeng; Liu, Pan; Zhou, Jianping; Liu, Renyi; Zhong, Yingli; Liu, Dong; Zhu, Jian-Kang

2014-01-01

403

Arabidopsis EDM2 promotes IBM1 distal polyadenylation and regulates genome DNA methylation patterns.  

PubMed

DNA methylation is important for the silencing of transposons and other repetitive elements in many higher eukaryotes. However, plant and mammalian genomes have evolved to contain repetitive elements near or inside their genes. How these genes are kept from being silenced by DNA methylation is not well understood. A forward genetics screen led to the identification of the putative chromatin regulator Enhanced Downy Mildew 2 (EDM2) as a cellular antisilencing factor and regulator of genome DNA methylation patterns. EDM2 contains a composite Plant Homeo Domain that recognizes both active and repressive histone methylation marks at the intronic repeat elements in genes such as the Histone 3 lysine 9 demethylase gene Increase in BONSAI Methylation 1 (IBM1) and is necessary for maintaining the expression of these genes by promoting mRNA distal polyadenylation. Because of its role in maintaining IBM1 expression, EDM2 is required for preventing CHG methylation in the bodies of thousands of genes. Our results thus increase the understanding of antisilencing, genome methylation patterns, and regulation of alternative RNA processing by intronic heterochromatin. PMID:24248388

Lei, Mingguang; La, Honggui; Lu, Kun; Wang, Pengcheng; Miki, Daisuke; Ren, Zhizhong; Duan, Cheng-Guo; Wang, Xingang; Tang, Kai; Zeng, Liang; Yang, Lan; Zhang, Heng; Nie, Wenfeng; Liu, Pan; Zhou, Jianping; Liu, Renyi; Zhong, Yingli; Liu, Dong; Zhu, Jian-Kang

2014-01-01

404

Development of a New Utm (universal Testing Machine) System for the Nano\\/micro In-Process Measurement  

Microsoft Academic Search

Micro UTM (Universal Testing Machines) are becoming increasingly popular for testing the mechanical properties of MEMS materials, metal thin films, and micro-molecule materials1-2. And, new miniature testing machines that can perform in-process measurement in SEM, TEM, and SPM are also needed. In this paper, a new micro UTM with a precision positioning system that can be fine positioning stage. Coarse

Hyunkyu Kweon; Sungdae Choi; Youngsik Kim; Kiho Nam

2006-01-01

405

Image processing as a tool to improve machine performance and process control  

Microsoft Academic Search

Image processing has been used as a tool to determine the trash content in cotton webs. The experiments showed that in particular seed coat particles are difficult to separate from the cotton during cleaning processes whereas neps, leaf and wooden fragments can easily be removed. A correlation between the number of seed coat particles and USTER-imperfections in the yarn has

D. Veit; I. Hormes; J. Bergmann; B. Wulfhorst

1996-01-01

406

Precision Machining  

NSDL National Science Digital Library

Basic machining processes are introduced on a Web site that is devoted to engineering fundamentals (1). Descriptions and illustrations of drilling, turning, grinding, and other common processes are provided for people with little to no prior machining knowledge. A waterjet is a non-traditional machining technology that uses high pressure streams of water with abrasive additives rather than solid cutting instruments to slice through metal and other materials. An in-depth discussion of waterjet operation and applications is available from Southern Methodist University (2). Waterjets are often cited as being much more precise than traditional machining techniques. The Waterjet Video Vault (3) contains clips of waterjet machines in action. The video of the foam cutting procedure is especially interesting, as it shows how quick and accurate the machining process can be. An online guide to cross process machining, which incorporates elements from various conventional and unconventional techniques, is provided by the Mechanical Engineering Department at Columbia University (4). Some remarkable and innovative techniques that have surfaced over the past few years are outlined, including underwater laser machining and plasma-assisted machining. Entirely different and exotic machining techniques are required for creating microelectromechanical systems (MEMS) and other extremely small devices. The Caltech Micromachining Laboratory (5) maintains an archive of research highlights and papers on its homepage, including a paper on a MEMS-driven flapping wing for a palm-sized aerial vehicle. An online article from Modern Machine Shop (6) outlines some new technologies and research in the area of high speed machining. A particularly interesting section of the article describes a system developed at the University of Florida that aims to enable micromachining to achieve rotational speeds of standard machining processes, specifically up to a half million rotations per minute. Cutting edge waterjet innovations are the subject of a February 2003 feature from a publication of the Society of Manufacturing Engineers (7). Extremely high pressure nozzles are being developed to improve cutting speed, and enhanced software for controlling machine movements is also a focus of study. This news article (8) from June 20, 2003 describes an electrochemical machining process that is being used to fabricate complex nanostructures. The work, produced by German and U.S. researchers, has the potential to compete with current lithographic processes.

Leske, Cavin.

407

Investigation of surface roughness in micro-electro discharge machining of nonconductive ZrO2 for MEMS application  

NASA Astrophysics Data System (ADS)

Micro-electro discharge machining technique, a noncontact machining process, is applied for drilling blind hole on nonconductive ZrO2 ceramic for MEMS application. A conductive layer of adhesive copper is applied on the workpiece surface to initiate the sparks. Kerosene is used as dielectric for creation of continuous conductive pyrolytic carbon layer on the machined surface. Experiments are conducted by varying the voltage (V), capacitance (C) and rotational speed (N). Correlating these variables a mathematical model for surface roughness (SR) is developed using Taguchi method. The results showed that the V and C are the significant parameters of SR in micro-EDM for nonconductive ZrO2 ceramic. The model also showed that SR increases with the increase of V and C.

Sabur, A.; Moudood, A.; Y Ali, M.; Maleque, M. A.

2013-12-01

408

Machining of three-dimensional microstructures in silicon by electro-discharge machining  

Microsoft Academic Search

Currently, nearly all microcomponents are fabricated by microelectronic production technologies like etching, deposition or other photolithographic techniques. In this way, the main emphasis has been put on surface micromechanics. The major challenge for the future will be the development of real three-dimensional microstructures. Electro-discharge machining (EDM) is a so-called non-conventional machining technique, whereby material is removed through the erosive action

Dominiek Reynaerts; Wim Meeusen; Hendrik Van Brussel

1998-01-01

409

Reverse time migration: A seismic processing application on the connection machine  

NASA Technical Reports Server (NTRS)

The implementation of a reverse time migration algorithm on the Connection Machine, a massively parallel computer is described. Essential architectural features of this machine as well as programming concepts are presented. The data structures and parallel operations for the implementation of the reverse time migration algorithm are described. The algorithm matches the Connection Machine architecture closely and executes almost at the peak performance of this machine.

Fiebrich, Rolf-Dieter

1987-01-01

410

Computer simulation of wire-EDM taper-cutting  

Microsoft Academic Search

Wire electro discharge machining (WEDM) has become one of the most popular processes for producing precise geometries in hard materials, such as those used in the tooling industry. Since it is recognized as a precision process, optimization of different aspects related to dimensional accuracy is a classic research topic. The so-called taper-cutting involves the generation of inclined ruled surfaces, and

Jose Antonio Sanchez; S. Plaza; Luis Norberto Lpez De Lacalle; Aitzol Lamikiz

2006-01-01

411

A batch-mode micromachining process for spherical structures  

NASA Astrophysics Data System (ADS)

This paper reports a self-aligned three-dimensional process (3D-SOULE) that incorporates batch-mode micro ultrasonic machining (USM), lapping and micro electro-discharge machining (EDM) for fabrication of concave and mushroom-shaped spherical structures from hard and brittle materials. To demonstrate the process, 1 mm structures are fabricated from glass and ruby spheres. The EDM technique is used to create the tool for ?USM from stainless steel spheres. Stainless steel 440, which provides a tool wear ratio <5%, is chosen as the tool material. A 2 2 array is used for batch processing. For an ultrasound generator frequency of 20 kHz and a vibration amplitude of 15 m, machining rates of 24 and 12 m min-1 are obtained for glass and ruby spheres, respectively. An approximate linear relationship is observed between the measured roughness (Ra) of the machined surface and the product of the fracture toughness (KIC) and the hardness (H) of the workpiece material (KIC3/2H1/2).

Li, Tao; Visvanathan, Karthik; Gianchandani, Yogesh B.

2014-02-01

412

INT Workshop on EDMs and CP-Violation -March 19-23, 2007 (Revised agenda 3/15/07)  

E-print Network

EDM experiment (PSI) 3:00-3:30 Coffee Break 3:30-4:00 Larry Hunter Electron EDM I 4:00-4:30 C-Y Liu Electron EDM II 4:30-5:00 Yannis Semertzidis Deuteron EDM 5:00-5:15 Klaus Kirch Muon EDM #12;Tuesday TalksINT Workshop on EDMs and CP-Violation - March 19-23, 2007 (Revised agenda 3/15/07) Monday Talks

Washington at Seattle, University of - Department of Physics, Electroweak Interaction Research Group

413

Incorporating Lamination Processing and Component Manufacturing in Electrical Machine Design Tools  

Microsoft Academic Search

Measures to improve the modeling of steel-sheet laminations in electrical machine design tools are studied. Only the magnetic properties, namely, the permeability (BH curves) and the iron losses are addressed. The sensitivity of these properties upon dimensional, directional (anisotropy) and excitation variations, as well as upon the electrical machines manufacturing steps is evaluated. The studied electrical machines manufacturing step are:

Waqas M. Arshad; Thomas Ryckebusch; F. Magnussen; H. Lendenmann; Bengt Eriksson; J. Soulard; B. Malmros

2007-01-01

414

Optimization of wire electrical discharge machining (WEDM) process parameters using Taguchi method  

Microsoft Academic Search

Wire electrical discharge machining (WEDM) is extensively used in machining of conductive materials when precision is of prime importance. Rough cutting operation in WEDM is treated as a challenging one because improvement of more than one machining performance measures viz. metal removal rate (MRR), surface finish (SF) and cutting width (kerf) are sought to obtain a precision work. Using Taguchi's

S. S. Mahapatra; Amar Patnaik

2006-01-01

415

Restricted Boltzmann machine: a non-linear substitute for PCA in spectral processing  

NASA Astrophysics Data System (ADS)

Context. Principal component analysis (PCA) is widely used to repair incomplete spectra, to perform spectral denoising, and to reduce dimensionality. Presently, no method has been found to be comparable to PCA on these three problems. New methods have been proposed, but are often specific to one problem. For example, locally linear embedding outperforms PCA in dimensionality reduction. However, it cannot be used in spectral denoising and spectral reparing. Wavelet transform can be used to denoise spectra; however, it cannot be used in dimensionality reduction. Aims: We provide a new method that can substitute PCA in incomplete spectra repairing, spectral denoising and spectral dimensionality reduction. Methods: A new method, restricted Boltzmann machine (RBM), is introduced in spectral processing. RBM is a particular type of Markov random field with two-layer architecture, and use Gibbs sampling method to train the algorithm. It can be used in spectral denoising, dimensionality reduction and spectral repairing. Results: The performance of RBM is comparable to PCA in spectral processing. It can repair the incomplete spectra better: the difference between the RBM repaired spectra and the original spectra is smaller than that between the PCA repaired spectra and the original spectra. The denoised spectra given by RBM is similar to those given by PCA. In dimensionality reduction, RBM performs better than PCA: the classification results of RBM+ELM (i.e. the extreme learning machine) is higher than those of PCA+ELM. This shows that RBM can extract the spectral features more efficiently than PCA. Thus, RBM is a good alternative method for PCA in spectral processing. The source code of RBM algorithm is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/576/A96

Bu, Yude; Zhao, Gang; Luo, A.-li; Pan, Jingchang; Chen, Yuqin

2015-04-01

416

Machine vision process monitoring on a poultry processing kill line: results from an implementation  

NASA Astrophysics Data System (ADS)

Researchers at the Georgia Tech Research Institute designed a vision inspection system for poultry kill line sorting with the potential for process control at various points throughout a processing facility. This system has been successfully operating in a plant for over two and a half years and has been shown to provide multiple benefits. With the introduction of HACCP-Based Inspection Models (HIMP), the opportunity for automated inspection systems to emerge as viable alternatives to human screening is promising. As more plants move to HIMP, these systems have the great potential for augmenting a processing facilities visual inspection process. This will help to maintain a more consistent and potentially higher throughput while helping the plant remain within the HIMP performance standards. In recent years, several vision systems have been designed to analyze the exterior of a chicken and are capable of identifying Food Safety 1 (FS1) type defects under HIMP regulatory specifications. This means that a reliable vision system can be used in a processing facility as a carcass sorter to automatically detect and divert product that is not suitable for further processing. This improves the evisceration line efficiency by creating a smaller set of features that human screeners are required to identify. This can reduce the required number of screeners or allow for faster processing line speeds. In addition to identifying FS1 category defects, the Georgia Tech vision system can also identify multiple "Other Consumer Protection" (OCP) category defects such as skin tears, bruises, broken wings, and cadavers. Monitoring this data in an almost real-time system allows the processing facility to address anomalies as soon as they occur. The Georgia Tech vision system can record minute-by-minute averages of the following defects: Septicemia Toxemia, cadaver, over-scald, bruises, skin tears, and broken wings. In addition to these defects, the system also records the length and width information of the entire chicken and different parts such as the breast, the legs, the wings, and the neck. The system also records average color and miss- hung birds, which can cause problems in further processing. Other relevant production information is also recorded including truck arrival and offloading times, catching crew and flock serviceman data, the grower, the breed of chicken, and the number of dead-on- arrival (DOA) birds per truck. Several interesting observations from the Georgia Tech vision system, which has been installed in a poultry processing plant for several years, are presented. Trend analysis has been performed on the performance of the catching crews and flock serviceman, and the results of the processed chicken as they relate to the bird dimensions and equipment settings in the plant. The results have allowed researchers and plant personnel to identify potential areas for improvement in the processing operation, which should result in improved efficiency and yield.

Usher, Colin; Britton, Dougl; Daley, Wayne; Stewart, John

2005-11-01

417

Progress towards a nuclear EDM measurement of Ra-225  

NASA Astrophysics Data System (ADS)

We are developing a long term program to search for the permanent electric dipole moment (EDM) of the Radium-225 nucleus. A nonzero nuclear EDM is a signature of of CP- and T-violating interactions within nuclei. Currently, the best experimental limits on these interactions are derived from EDM measurements of Mercury-199. The Ra-225 radioisotope (half-life of 15 days) is an attractive alternative because, due to its peculiar shape (octupole deformation), it is predicted to be 10^2-10^3 times more sensitive to these types of interactions than Hg-199. In our measurement scheme, Ra atoms are first laser cooled & trapped in a magneto-optical trap (MOT) and then transferred to an optical dipole trap (ODT), both of which have already been demonstrated. Currently being studied is the motion of this ODT into the science chamber and the transfer of atoms into a second ODT. We will report on progress towards measurements of atomic properties necessary for the EDM search and the EDM search itself.

Singh, Jaideep; Dietrich, M. R.; Kalita, M.; Parker, R. H.; Sulai, I. A.; Bailey, K.; Greene, J. P.; Mueller, P.; O'Connor, T. P.; Holt, R. J.; Lu, Z.-T.

2011-06-01

418

Atomic properties of Ra for a future EDM measurement  

NASA Astrophysics Data System (ADS)

Searches for non-zero permanent electric-dipole moments (EDM) of particles, atoms, and molecules represent remarkable opportunity to probe new physics beyond the standard model. The EDMs arise from the violations of both parity and time-reversal invariance. Atomic EDMs caused by the nuclear parity and time invariance violating effects are enhanced in certain diamagnetic atoms, such as ^199Hg and ^225Ra. For the latter, there is additional enhancement due to close states of opposite parity and the large nuclear charge Z [Dzuba et al., PRA 61, 062509 (2000)]. The search for EDM in ^225Ra is presently underway [Holt et al., Nucl. Phys. A 844, 53c (2010)]. Few atomic properties of Ra are experimentally known. In this work, we carry out a systematic study of Ra atomic properties of interest to the EDM search using recently developed relativistic ab initio method [Safronova at. al, PRA 80, 012516 (2009)] that allows to accurately treat correlation corrections in atoms with a few valence electrons. This method combines the coupled-cluster method, that yielded excellent results for monovalent systems, with the configuration-interaction approach. We have calculated energy levels, electric-dipole matrix elements, lifetimes, hyperfine constants, and polarizabilities.

Zuhrianda, Z.; Safronova, Marianna; Porsev, Sergey; Kozlov, Mikhail

2012-06-01

419

Evaluation of surface water resources from machine-processing of ERTS multispectral data  

NASA Technical Reports Server (NTRS)

The surface water resources of a large metropolitan area, Marion County (Indianapolis), Indiana, are studied in order to assess the potential value of ERTS spectral analysis to water resources problems. The results of the research indicate that all surface water bodies over 0.5 ha were identified accurately from ERTS multispectral analysis. Five distinct classes of water were identified and correlated with parameters which included: degree of water siltiness; depth of water; presence of macro and micro biotic forms in the water; and presence of various chemical concentrations in the water. The machine processing of ERTS spectral data used alone or in conjunction with conventional sources of hydrological information can lead to the monitoring of area of surface water bodies; estimated volume of selected surface water bodies; differences in degree of silt and clay suspended in water and degree of water eutrophication related to chemical concentrations.

Mausel, P. W.; Todd, W. J.; Baumgardner, M. F.; Mitchell, R. A.; Cook, J. P.

1976-01-01

420

Hybrid Metaheuristics for Solving a Fuzzy Single Batch-Processing Machine Scheduling Problem  

PubMed Central

This paper deals with a problem of minimizing total weighted tardiness of jobs in a real-world single batch-processing machine (SBPM) scheduling in the presence of fuzzy due date. In this paper, first a fuzzy mixed integer linear programming model is developed. Then, due to the complexity of the problem, which is NP-hard, we design two hybrid metaheuristics called GA-VNS and VNS-SA applying the advantages of genetic algorithm (GA), variable neighborhood search (VNS), and simulated annealing (SA) frameworks. Besides, we propose three fuzzy earliest due date heuristics to solve the given problem. Through computational experiments with several random test problems, a robust calibration is applied on the parameters. Finally, computational results on different-scale test problems are presented to compare the proposed algorithms. PMID:24883359

Molla-Alizadeh-Zavardehi, S.; Tavakkoli-Moghaddam, R.; Lotfi, F. Hosseinzadeh

2014-01-01

421

Hybrid metaheuristics for solving a fuzzy single batch-processing machine scheduling problem.  

PubMed

This paper deals with a problem of minimizing total weighted tardiness of jobs in a real-world single batch-processing machine (SBPM) scheduling in the presence of fuzzy due date. In this paper, first a fuzzy mixed integer linear programming model is developed. Then, due to the complexity of the problem, which is NP-hard, we design two hybrid metaheuristics called GA-VNS and VNS-SA applying the advantages of genetic algorithm (GA), variable neighborhood search (VNS), and simulated annealing (SA) frameworks. Besides, we propose three fuzzy earliest due date heuristics to solve the given problem. Through computational experiments with several random test problems, a robust calibration is applied on the parameters. Finally, computational results on different-scale test problems are presented to compare the proposed algorithms. PMID:24883359

Molla-Alizadeh-Zavardehi, S; Tavakkoli-Moghaddam, R; Lotfi, F Hosseinzadeh

2014-01-01

422

An Operating and Diagnostic Knowledge-Based System for Wire EDM  

Microsoft Academic Search

\\u000a The selection of machining parameters and machine settings for wire electrical discharge machining (WEDM) depends mainly on\\u000a both technologies and experience provided by machine tool manufacturers. The present work designs a knowledge-based system\\u000a (KBS) to select the optimal process parameters settings and diagnose the machining conditions for WEDM. Moreover, the present\\u000a results supply users of WEDM with beneficial data avoiding

Samy Ebeid; Raouf Fahmy; Sameh Habib

2003-01-01

423

Focused particle beam nano-machining: the next evolution step towards simulation aided process prediction.  

PubMed

During the last decade, focused ion beam processing has been developed from traditionally used Ga(+) liquid ion sources towards higher resolution gas field ion sources (He(+) and Ne(+)). Process simulations not only improve the fundamental understanding of the relevant ion-matter interactions, but also enable a certain predictive power to accelerate advances. The historic 'gold' standard in ion-solid simulations is the SRIM/TRIM Monte Carlo package released by Ziegler, Ziegler and Biersack 2010 Nucl. Instrum. Methods B 268 1818-23. While SRIM/TRIM is very useful for a myriad of applications, it is not applicable for the understanding of the nanoscale evolution associated with ion beam nano-machining as the substrate does not evolve with the sputtering process. As a solution for this problem, a new, adapted simulation code is briefly overviewed and finally addresses these contributions. By that, experimentally observed Ne(+) beam sputter profiles can be explained from a fundamental point of view. Due to their very good agreement, these simulations contain the potential for computer aided optimization towards predictable sputter processes for different nanotechnology applications. With these benefits in mind, the discussed simulation approach represents an enormous step towards a computer based master tool for adaptable ion beam applications in the context of industrial applications. PMID:25580777

Plank, Harald

2015-02-01

424

Focused particle beam nano-machining: the next evolution step towards simulation aided process prediction  

NASA Astrophysics Data System (ADS)

During the last decade, focused ion beam processing has been developed from traditionally used Ga+ liquid ion sources towards higher resolution gas field ion sources (He+ and Ne+). Process simulations not only improve the fundamental understanding of the relevant ionmatter interactions, but also enable a certain predictive power to accelerate advances. The historic gold standard in ionsolid simulations is the SRIM/TRIM Monte Carlo package released by Ziegler, Ziegler and Biersack 2010 Nucl. Instrum. Methods B 268 181823. While SRIM/TRIM is very useful for a myriad of applications, it is not applicable for the understanding of the nanoscale evolution associated with ion beam nano-machining as the substrate does not evolve with the sputtering process. As a solution for this problem, a new, adapted simulation code is briefly overviewed and finally addresses these contributions. By that, experimentally observed Ne+ beam sputter profiles can be explained from a fundamental point of view. Due to their very good agreement, these simulations contain the potential for computer aided optimization towards predictable sputter processes for different nanotechnology applications. With these benefits in mind, the discussed simulation approach represents an enormous step towards a computer based master tool for adaptable ion beam applications in the context of industrial applications.

Plank, Harald

2015-02-01

425

Machine processing of S-192 and supporting aircraft data: Studies of atmospheric effects, agricultural classifications, and land resource mapping  

NASA Technical Reports Server (NTRS)

Two tasks of machine processing of S-192 multispectral scanner data are reviewed. In the first task, the effects of changing atmospheric and base altitude on the ability to machine-classify agricultural crops were investigated. A classifier and atmospheric effects simulation model was devised and its accuracy verified by comparison of its predicted results with S-192 processed results. In the second task, land resource maps of a mountainous area near Cripple Creek, Colorado were prepared from S-192 data collected on 4 August 1973.

Thomson, F.

1975-01-01

426

Influence of electrical discharge machining on sliding friction and wear of WCNi cemented carbide  

Microsoft Academic Search

Tribological characteristics of fine-grained WC8wt%Ni with different surface finishing conditions corresponding to sequential wire electrical discharge machining (wire-EDM) or grinding were investigated by performing dry reciprocating sliding experiments on TE77 pin-on-plate equipment with WC6wt%Co as mating material. Surface finishes and wear surfaces were characterized using surface topography scanning, SEM analysis and EDX spectrometry. The decreased wear resistance due to wire-EDM

K. Bonny; P. De Baets; J. Van Wittenberghe; Y. Perez Delgado; J. Vleugels; O. Van der Biest; B. Lauwers

2010-01-01

427

Wire electric discharge machining induced titanium hydride in Ti46Al2Cr alloy  

Microsoft Academic Search

Wire electric discharge machining (Wire-EDM) induced a new phase in Ti46Al2Cr (in at.%) intermetallic alloy has been identified by using X-ray diffraction technique. The new phase is found to be neither TiO2 nor Al2O3, but well consistent with fcc structure titanium hydride with the lattice parameter of 4.494.50 . The new phase exists in the wire-EDM cut alloy surface layer

G. W. Qin; K. Oikawa; G. D. W. Smith; S. M. Hao

2003-01-01

428

Influence of electrical discharge machining on the sliding contact response of cemented carbides  

Microsoft Academic Search

The correlation between electrical-discharge machining (EDM) and surface integrity and its influence on the sliding contact response of a fine-grained WC-10%wtCo hardmetal have been studied. Different surface finish conditions were evaluated corresponding to sequential EDM as well as grinding and polishing employing diamond as abrasive. Surface integrity was characterized in detail for all conditions through scanning electron microscopy (SEM). Sliding

L. Llanes; E. Idaez; E. Mart??nez; B. Casas; J. Esteve

2001-01-01

429

Preliminary Measurements for an Electron EDM Experiment in ThO  

E-print Network

#12;#12;Preliminary Measurements for an Electron EDM Experiment in ThO A thesis presented by Yulia for an Electron EDM Experiment in ThO Abstract The ACME collaboration aims to measure the eEDM via Ramsey the sensitivity of the H state to magnetic fields, which can be a source of noise and systematic errors in the eEDM

Gabrielse, Gerald

430

Progress toward an EDM measurement in Ra-225  

NASA Astrophysics Data System (ADS)

We are developing an EDM search based on laser-cooled and trapped Ra-225 (half-life = 15 d) atoms. Due to octupole deformation of the nucleus, Ra-225 is predicted to be 2-3 orders of magnitude more sensitive to T-violating interactions than Hg-199, which currently sets the most stringent limits in the nuclear sector. In preparation of an EDM measurement, we have trapped radium atoms first in a MOT and then transferred them to a far-off-resonant optical dipole trap. We will report progress towards the EDM search and the measurements of relevant atomic properties. This work is supported by DOE, Office of Nuclear Physics, under contract No. DE-AC02-06CH11357.

Sulai, I. A.; Trimble, W. L.; Parker, R. H.; Bailey, K.; Greene, J. P.; Holt, R. J.; Korsch, W.; Lu, Z. T.; Mueller, P.; O'Connor, T. P.; Singh, J.

2010-03-01

431

Evaluation of a possible optical e-EDM measurement  

NASA Astrophysics Data System (ADS)

Since its proposed existence by Purcell and Ramsey in 1950, the possibility of an electron electric dipole moment (e-EDM) has been the subject of extensive theoretical and experimental investigation. Here we describe an ongoing effort to probe for an e-EDM by measuring the energy difference between two states of the PbF molecule that differ only by their orientation with respect to an applied external electric field. Specifically, we describe a possible optical Ramsey resonance experiment utilizing rotating linearly polarized light. We present initial tests of this scheme, including measurement of a small angle of rotation of a polarized beam splitter and measurement of optical Stark spectroscopy of the PbF molecule. We discuss these results and the limitations they place on a measurement of an e-EDM.

Fan, Haoquan; Coker, James; Yang, Tao Zh.; Gillean, Jerry; Shafer-Ray, N. E.

2011-06-01

432

Metallurgical Analysis of Crack Initiation of Wire-Cut Electrical Discharge-Machined Spline Actuators Made of 17-4 PH Stainless Steel  

Microsoft Academic Search

Spline actuators made of investment cast 17-4 PH (precipitation hardening) stainless steel were found to contain micro-cracks.\\u000a The cracked actuators were subjected to optical and scanning electron microscopy and hardness testing, which revealed that\\u000a the failure occurred due to fatigue crack initiation and growth after electrical discharge machining (EDM). The rehardened\\u000a layer produced by the EDM remained after machining, and

Ahmad-Reza Etemadi; Bahram Fazel; Armin Emami

433

A model for Intelligent Random Access Memory architecture (IRAM) cellular automata algorithms on the Associative String Processing machine (ASTRA)  

E-print Network

In the near future, the computer performance will be completely determined by how long it takes to access memory. There are bottle-necks in memory latency and memory-to processor interface bandwidth. The IRAM initiative could be the answer by putting Processor-In-Memory (PIM). Starting from the massively parallel processing concept, one reached a similar conclusion. The MPPC (Massively Parallel Processing Collaboration) project and the 8K processor ASTRA machine (Associative String Test bench for Research \\& Applications) developed at CERN \\cite{kuala} can be regarded as a forerunner of the IRAM concept. The computing power of the ASTRA machine, regarded as an IRAM with 64 one-bit processors on a 64$\\times$64 bit-matrix memory chip machine, has been demonstrated by running statistical physics algorithms: one-dimensional stochastic cellular automata, as a simple model for dynamical phase transitions. As a relevant result for physics, the damage spreading of this model has been investigated.

Rohrbach, F; Vesztergombi, G

1997-01-01

434

Search for a permanent EDM using laser cooled radioactive atom  

NASA Astrophysics Data System (ADS)

An Electric Dipole Moment (EDM) of the elementary particle is a good prove to observe the phenomena beyond the Standard Model. A non-zero EDM shows the violation of the time reversal symmetry, and under the CPT invariance it means the CP violation. In paramagnetic atoms, an electron EDM results in an atomic EDM enhanced by the factor of the 3rd power of the charge of the nucleus due the relativistic effects. A heaviest alkali element francium (Fr), which is the radioactive atom, has the largest enhancement factor K ~ 895. Then, we are developing a high intensity laser cooled Fr factory at Cyclotron and Radioisotope Center (CYRIC), Tohoku University to perform the search for the EDM of Fr with the accuracy of 10-29 e cm. The important points to overcome the current accuracy limit of the EDM are to realize the high intensity Fr source and to reduce the systematic error due to the motional magnetic field and inhomogeneous applied field. To reduce the dominant component of the systematic errors mentioned above, we will confine the Fr atoms in the small region with the Magneto-Optical Trap and optical lattice using the laser cooling and trapping techniques. The construction of the experimental apparatus is making progress, and the new thermal ionizer already produces the Fr of ~106 ions/s with the primary beam intensity 200 nA. The developments of the laser system and optical equipments are in progress, and the present status and future plan of the experimental project is reported.

Sakemi, Y.; Harada, K.; Hayamizu, T.; Itoh, M.; Kawamura, H.; Liu, S.; Nataraj, H. S.; Oikawa, A.; Saito, M.; Sato, T.; Yoshida, H. P.; Aoki, T.; Hatakeyama, A.; Murakami, T.; Imai, K.; Hatanaka, K.; Wakasa, T.; Shimizu, Y.; Uchida, M.

2011-07-01

435

Improving the Limit on the Electron EDM: Data Acquisition and Systematics Studies in the ACME  

E-print Network

Improving the Limit on the Electron EDM: Data Acquisition and Systematics Studies in the ACME Gabrielse Paul William Hess Improving the Limit on the Electron EDM: Data Acquisition and Systematics upper limit on the size of the electron's permanent electric dipole moment (EDM). The existence

Gabrielse, Gerald

436

An Investigation into Improving Worn Electrode Reliability in the Electrical Discharge Machining Process  

Microsoft Academic Search

In this paper, the use of a strengthstress interference model to study electrode reliability during wear in electrical discharge\\u000a machining has been reported. In order to improve the electrode reliability, the Taguchi method, which is a powerful tool for\\u000a parameter design of performance characteristics is used to determine machining parameters for minimum electrode wear ratio\\u000a in electrical discharge machining operations.

J. L. Lin; K. S. Wang; B. H. Yan; Y. S. Tarng

2000-01-01

437

Wireless Monitoring of Workpiece Material Transitions and Debris Accumulation in Micro-Electro-Discharge Machining  

Microsoft Academic Search

Wireless signals are inherently generated with each discharge in micro-electro-discharge machining (??EDM), allowing direct observation of discharge quality. While traditional methods of monitoring machining quality rely on electrical characteristics at the discharge supply terminals, the wireless method provides more accurate information because it is less affected by electrical parasitics in the supply loop and by spatial averaging. The depth location

Mark T. Richardson; Yogesh B. Gianchandani

2010-01-01

438

Study on the electro-discharge machining of a hot pressed aluminum oxide based ceramic  

Microsoft Academic Search

In this paper, the machinability of ceramics is studied according to their physical properties. Research results show that EDM is suitable for conductive ceramics. The mechanism of electro-discharge machining ceramics is investigated. The effects on material removal rate, surface roughness, and diameter of discharge points by various parameters are measured and discussed.

J. H. Zhang; T. C. Lee; W. S. Lau

1997-01-01

439

Tool vibration detection with eddy current sensors in machining process and computation of stability lobes using fuzzy classifiers  

Microsoft Academic Search

Today the knowledge of a process is very important for engineers to find optimal combination of control parameters warranting productivity, quality and functioning without defects and failures. In our laboratory, we carry out research in the field of high speed machining with modelling, simulation and experimental approaches. The aim of our investigation is to develop a software allowing the cutting

Arnaud Devillez; Daniel Dudzinski

2007-01-01

440

For a new edition of the Encyclopedia of Language and Linguistics. The History of Natural Language Processing and Machine Translation  

Microsoft Academic Search

The article surveys fifty years of work in computational language processing and machine translation, and suggests that a great number of the important ideas were present in the earliest days and hampered only back lack of computational power. Sections review the influence of linguistics proper on the computational area, as well as the influence of artificial intelligence and concerns from

Yorick Wilks

441

Determination of optimal cutting parameters in wire electrical discharge machining  

Microsoft Academic Search

Owing to the complexity of wire electrical discharge machining (wire-EDM), it is very difficult to determine optimal cutting parameters for improving cutting performance. The paper utilizes a feedforward neural network to associate the cutting parameters with the cutting performance. A simulated annealing (SA) algorithm is then applied to the neural network for solving the optimal cutting parameters based on a

Y. S. Tarng; S. C. Ma; L. K. Chung

1995-01-01

442

A study of ultrasonic-aided wire electrical discharge machining  

Microsoft Academic Search

An investigation has been made into the combined technology of ultrasonic and wire electrical discharge machining (W-EDM), in which the design of the vibrating device is described. The theory to describe the vibration modes of the wire under the action of ultrasonic has been established. Experimental results show that wire vibration induced by ultrasonic action has a significant effect on

Z. N. Guo; T. C. Lee; T. M. Yue; W. S. Lau

1997-01-01

443

Simple Machines  

NSDL National Science Digital Library

Through a five-lesson series with five activities, students are introduced to six simple machinesinclined plane, wedge, screw, lever, pulley, wheel-and-axleas well as compound machines, which are combinations of two or more simple machines. Once students understand about work (work = force x distance), they become familiar with the machines' mechanical advantages, and see how they make work easier. Through an introduction to compound machines, students begin to think critically about machine inventions and their pervasive roles in our lives. After learning about Rube Goldberg contraptionsabsurd inventions that complete simple tasks in complicated waysthey evaluate the importance and usefulness of the many machines around them. Through the hands-on activities, students draw designs for contraptions that could move a circus elephant into a rail car, create a construction site ramp design by measuring different inclined planes and calculating the ideal vs. actual mechanical advantage of each, compare the theoretical and actual mechanical advantages of different pulley systems conceived to save a whale, build and test grape catapults made with popsicle sticks and rubber bands, and follow the steps of the engineering design process to design and build Rube Goldberg machines.

Integrated Teaching and Learning Program,

444

Journal of Materials Processing Technology 183 (2007) 7787 Analytical modelling of residual stresses in machining  

E-print Network

for prediction of residual stresses in machining. In the thermo-mechanical model of residual stresses both on the surface of workpieces leading to a reduction in the fatigue life of parts. Residual stresses raise stresses to increase fatigue life using optimum machining conditions [1]. Different approaches

Alaca, B. Erdem

2007-01-01

445

Machines of life: catalogue, stochastic process modeling, probabilistic reverse engineering and the PIs- from Aristotle to Alberts  

E-print Network

Molecular machines consist of either a single protein or a macromolecular complex composed of protein and RNA molecules. Just like their macroscopic counterparts, each of these nano-machines has an engine that "transduces" input energy into an output form which is then utilized by its coupling to a transmission system for appropriate operations. The theory of heat engines, pioneered by Carnot, rests on the second law of equilibrium thermodynamics. However, the engines of molecular machines, operate under isothermal conditions far from thermodynamic equilibrium. Moreover, one of the possible mechanisms of energy transduction, popularized by Feynman and called Brownian ratchet, does not even have any macroscopic counterpart. But, {\\it molecular machine is not synonymous with Brownian ratchet}; a large number of molecular machines actually execute a noisy power stroke, rather than operating as Brownian ratchet. The man-machine analogy, a topic of intense philosophical debate in which many leading philosophers like Aristotle and Descartes participated, was extended to similar analogies at the cellular and subcellular levels after the invention of optical microscope. The idea of molecular machine, pioneered by Marcelo Malpighi, has been pursued vigorously in the last fifty years. It has become a well established topic of current interdisciplinary research as evident from the publication of a very influential paper by Alberts towards the end of the twentieth century. Here we give a non-technical overview of the strategies for (a) stochastic modeling of mechano-chemical kinetic processes, and (b) model selection based on statistical inference drawn from analysis of experimental data. It is written for non-experts and from a broad perspective, showing overlapping concepts from several different branches of physics and from other areas of science and technology.

Debashish Chowdhury

2012-03-14

446

Efficient production by laser materials processing integrated into metal cutting machines  

NASA Astrophysics Data System (ADS)

Beam guidance of high power YAG-laser (cw, pulsed, Q-switched) with average powers up to 2000 W by flexible glass fibers facilitates the integration of the laser beam as an additional tool into metal cutting machines. Hence, technologies like laser cutting, joining, hardening, caving, structuring of surfaces and laser-marking can be applied directly inside machining centers in one setting, thereby reducing the flow of workpieces resulting in a lowering of costs and production time. Furthermore, materials with restricted machinability--especially hard materials like ceramics, hard metals or sintered alloys--can be shaped by laser-caving or laser assisted machining. Altogether, the flexibility of laser integrated machining centers is substantially increased or the efficiency of a production line is raised by time-savings or extended feasibilities with techniques like hardening, welding or caving.

Wiedmaier, M.; Meiners, E.; Dausinger, Friedrich; Huegel, Helmut

1994-09-01

447

Recent Results from the PbO* Electron EDM Experiment  

NASA Astrophysics Data System (ADS)

Observation of an electric dipole moment (EDM) of the electron would imply new physics with CP violation beyond the Standard Model. A new generation of experiments propose to take advantage of the enhanced sensitivity of polar molecules to an electron EDM due to their enormous effective internal electric fields (>10 GV/cm). In addition, molecular states which exhibit parity doubling can be used to effectively reverse the direction of the internal electric field without changing external fields applied to the molecules. This novel experimental control leads to an enormous suppression of the systematic effects most common to EDM experiments. Our experiment uses a high temperature vapor cell containing PbO. The large vapor density leads to a higher counting rate than traditional beam experiments. Recent improvements to the experimental apparatus and new analysis techniques have now increased our optimal statistical sensitivity to better than 10-27 e.cm/day, potentially allowing for an improved limit on the electron EDM in a few days integration time. e will discuss these improvements as well as preliminary results and investigations of systematic effects.

Hamilton, Paul; Eckel, Stephen; Kirilov, Emil; Smith, Hunter; Demille, David

2011-06-01

448

Cold Molecular Ion Source for an electron EDM measurement  

Microsoft Academic Search

Molecular ions confined inside a Paul trap offer a potentially sensitive system for a search of the electron electric dipole moment. Large effective electric fields at the electron can be obtained by using molecules. Trapping these molecules allows for long spin coherence times to probe electron EDM induced energy splittings. We report on a supersonic expansion that cools ions created

Russell Stutz; Aaron Leanhardt; Laura Sinclair; Eric Cornell

2006-01-01

449

An Electron EDM Search Using Trapped Molecular Ions  

Microsoft Academic Search

A sample of trapped molecular ions offers unique possibilities to search for a permanent electron electric dipole moment (EDM). Specifically, we plan to perform this search using the unpaired electron spins in the ^3delta1 state of trapped HfF^+ molecular ions. Ions are easy to trap which will provide the long coherence times necessary to measure the small energy differences associated

Laura Sinclair; John Bohn; Aaron Leanhardt; Edmund Meyer; Russell Stutz; Eric Cornell

2007-01-01

450

Candidate Molecular Ions for an Electron EDM Experiment  

Microsoft Academic Search

An experiment has been proposed to trap heteronuclear diatomic molecular ions to search for the electron's electric dipole moment (eEDM - see accompanying poster). In order to pick a suitable molecule many parameters must be considered, including the polarizability, rotational constant and nuclear charge of the heavy atom, as well as the expected size of the effective electric field inside

E. Meyer; E. Cornell; J. Bohn

2005-01-01

451

Fundamental study on corrosion of cemented carbide during wire EDM  

Microsoft Academic Search

In this paper, a study on the corrosion of a workpiece of cemented carbide submerged in a dielectric of water for a lengthy time during wire EDM is described. When the cemented carbide is submerged in water for a long time, the surface of the cemented carbide becomes brittle, because the cobalt which is the binder of cemented carbide is

Haruki Obara; Harutoshi Satou; Masatoshi Hatano

2004-01-01

452

Composite Wires with High Tensile Core for Wire EDM  

Microsoft Academic Search

In recent years wire EDM cutting speeds and final surface roughness have been continuously improving. Much higher cutting speeds during roughing and surface roughness values lower than 0.1 ?m Ra during finishing can be obtained. These enhancements are mostly attributed to the use of more advanced generator technology, but also to the type of wire. This paper discusses the use

J.-P. Kruth; B. Lauwers; B. Schacht; J. van Humbeeck

2004-01-01

453

Tool vibration detection with eddy current sensors in machining process and computation of stability lobes using fuzzy classifiers  

NASA Astrophysics Data System (ADS)

Today the knowledge of a process is very important for engineers to find optimal combination of control parameters warranting productivity, quality and functioning without defects and failures. In our laboratory, we carry out research in the field of high speed machining with modelling, simulation and experimental approaches. The aim of our investigation is to develop a software allowing the cutting conditions optimisation to limit the number of predictive tests, and the process monitoring to prevent any trouble during machining operations. This software is based on models and experimental data sets which constitute the knowledge of the process. In this paper, we deal with the problem of vibrations occurring during a machining operation. These vibrations may cause some failures and defects to the process, like workpiece surface alteration and rapid tool wear. To measure on line the tool micro-movements, we equipped a lathe with a specific instrumentation using eddy current sensors. Obtained signals were correlated with surface finish and a signal processing algorithm was used to determine if a test is stable or unstable. Then, a fuzzy classification method was proposed to classify the tests in a space defined by the width of cut and the cutting speed. Finally, it was shown that the fuzzy classification takes into account of the measurements incertitude to compute the stability limit or stability lobes of the process.

Devillez, Arnaud; Dudzinski, Daniel

2007-01-01

454

Seismic interpretation using Support Vector Machines implemented on Graphics Processing Units  

SciTech Connect

Support Vector Machines (SVMs) estimate lithologic properties of rock formations from seismic data by interpolating between known models using synthetically generated model/data pairs. SVMs are related to kriging and radial basis function neural networks. In our study, we train an SVM to approximate an inverse to the Zoeppritz equations. Training models are sampled from distributions constructed from well-log statistics. Training data is computed via a physically realistic forward modeling algorithm. In our experiments, each training data vector is a set of seismic traces similar to a 2-d image. The SVM returns a model given by a weighted comparison of the new data to each training data vector. The method of comparison is given by a kernel function which implicitly transforms data into a high-dimensional feature space and performs a dot-product. The feature space of a Gaussian kernel is made up of sines and cosines and so is appropriate for band-limited seismic problems. Training an SVM involves estimating a set of weights from the training model/data pairs. It is designed to be an easy problem; at worst it is a quadratic programming problem on the order of the size of the training set. By implementing the slowest part of our SVM algorithm on a graphics processing unit (GPU), we improve the speed of the algorithm by two orders of magnitude. Our SVM/GPU combination achieves results that are similar to those of conventional iterative inversion in fractions of the time.

Kuzma, H A; Rector, J W; Bremer, D

2006-06-22

455

Machine Learning based on Software Metrics for Process Assessment Steffen Herbold  

E-print Network

that improve the state of the art. Machine learning has the advantage of being unbiased, whereas experts instinctively use their intuition and expertise, which may be biased. 1. Introduction In software development

Grabowski, Jens

456

Optimizing target surfaces for inertial confinement fusion experiments using micro-electrical discharge machining  

NASA Astrophysics Data System (ADS)

Cone guided fast-ignition laser fusion uses a re-entrant cone target to allow laser access through the plasma overlying the compressed core. Current experiments emulate that situation with a conical hole in an aluminum foil. It is critical that the 10 ?m diameter laser spot be centered on the 30 ?m diameter flat cone tip. Alignment is achieved by retro-imaging a low power beam from the cone tip. Micron scale roughness on the cone tip limits reflected light intensity making alignment difficult; an improved surface finish is required. The buried cone targets are fabricated by micro-electrical discharge machining (EDM). Various parameters are investigated to decrease the roughness and to improve the uniformity of the EDM cone tip surface: EDM wire material and shape, electrode voltage, machine capacitance, and machining speed. Results of surface roughness, uniformity, and material removal rate will be presented.

Waltz, C.; Jaquez, J. J.

2011-11-01

457

Parallel-machine rescheduling with machine disruptions  

Microsoft Academic Search

In this study we consider a rescheduling problem on identical parallel machines. The rescheduling is undertaken because of a period of unavailability on one of the machines. We consider the total flow time as an efficiency measure and stability is gauged in terms of the number of jobs processed on different machines in the original and new schedules. We show

Meral Azizoglu; Oguzhan Alagz

2005-01-01

458

An Insight to the Modeling of 1 1 Rib Loop Formation Process on Circular Weft Knitting Machine using Computer  

NASA Astrophysics Data System (ADS)

The mechanics of single jersey loop formation is well-reported is literature. However, as the concept of any model of double jersey loop formation process is not available in accessible international literature. Therefore, it was planned to develop a model of 1 1 rib loop formation process on dial and cylinder machine using computer so that the influence of various input variables on the final loop length as well on the profile of tension on the yarn inside Knitting Zone (KZ) can be understood. The model provides an insight into the mechanics of 1 1 rib loop formation system on dial and cylinder machine. Besides, the degree of agreement between predicted and measured values of loop length and cam forces as well as theoretical analysis of the model have justified the acceptability of the model.

Ray, Sadhan Chandra

2015-03-01

459

Development of a New Utm (universal Testing Machine) System for the Nano/micro In-Process Measurement  

NASA Astrophysics Data System (ADS)

Micro UTM (Universal Testing Machines) are becoming increasingly popular for testing the mechanical properties of MEMS materials, metal thin films, and micro-molecule materials1-2. And, new miniature testing machines that can perform in-process measurement in SEM, TEM, and SPM are also needed. In this paper, a new micro UTM with a precision positioning system that can be fine positioning stage. Coarse positioning is implemented by step motor. The size, load output and used in SEM, TEM, and SPM have been proposed. Bimorph type PZT precision actuator is used in displacement output of bimorph type UTM are 1096422(mm), about 35g, and 0.4 mm, respectively. And the displacement output is controlled in the block digital form. The results of the analysis and basic properties of positioning system and the UTM system are presented. In addition, the experiment results of in-process measurement during tensile load in SEM and AFM are showed.

Kweon, Hyunkyu; Choi, Sungdae; Kim, Youngsik; Nam, Kiho

460

Effect of composition and processing on the thermal fatigue and toughness of high performance die steels. Final report  

SciTech Connect

The objective of this study was to improve average die life by optimizing die steel composition and the die processing. Four different steels, K,Q,C and Premium Grade H-13 have been investigated for thermal fatigue resistance and toughness. Optimum heat treatment processing has been determined for each steel with respect to austenitizing temperature and tempering conditions. The effect of the quenching rate on the thermal fatigue resistance and toughness of the die steels and the effect of Electro-Discharge Machining (EDM) on the thermal fatigue resistance were also determined. The immersion thermal fatigue specimen developed at CWRU was used to determine the thermal fatigue resistance as characterized by the two parameters of average maximum crack length and total crack area. The Charpy V-notch impact test was used over a -100{degrees}F to 450{degrees}F testing temperature range to evaluate the toughness and the brittle-ductile transition behavior. K steel has been identified as superior in performance compared to Premium Grade H-13. Q and C provide lower toughness and thermal fatigue resistance than H-13. Faster cooling rates provide higher thermal fatigue resistance and toughness. Higher austenitizing temperatures such as 1925{degrees}F compared to 1875{degrees}F provide better thermal fatigue resistance, but lower austenitizing temperatures of 1875{degrees}F provide better toughness. Higher hardness improves thermal fatigue resistance, but reduces toughness. A minimum of Rc 46 hardness is desired for aluminum die casting dies. EDM reduces the thermal fatigue resistance compared to conventional machining operations. When the EDM process of multiple small steps of decreasing energy and post-EDM treatments are employed, the effect can be reduced to a very slight amount. Preliminary evidence of the superior performance of the K steel has been provided by ongoing field testing of inserts in multiple cavity dies.

Wallace, J.F.; Wang, Y.; Schwam, D.

1997-06-01

461

Analysis of three-dimensional transient heat conduction for predicting wire erosion in the wire electrical discharge machining process  

Microsoft Academic Search

The three-dimensional transient temperature distribution and crater formation of the wire during a single discharge period in the electrical discharge machining process are determined by an explicit finite-difference model. The heat load on the wire is simulated by a variable heat flux boundary condition that part of the circumference where the discharge channel interacts with the wire. The heat-flux value

S. Banerjee; B. V. S. S. S. Prasad; P. K. Mishra

1997-01-01

462

Development and control towards a parallel water hydraulic weld\\/cut robot for machining processes in ITER vacuum vessel  

Microsoft Academic Search

This paper presents a special robot, able to carry out welding and machining processes from inside the ITER vacuum vessel (VV), consisting of a five degree-of-freedom parallel mechanism, mounted on a carriage driven by two electric motors on a rack. The kinematic design of the robot has been optimised for ITER access and a hydraulically actuated pre-prototype built. A hybrid

Huapeng Wu; Heikki Handroos; Pekka Pessi; Juha Kilkki; Lawrence Jones

2005-01-01

463

Optical dipole trapping of radium atoms for EDM search  

NASA Astrophysics Data System (ADS)

We are developing an EDM search based on laser-cooled and trapped Ra-225 (half-life = 15 d) atoms. Due to octupole deformation of the nucleus, Ra-225 is predicted to be 2-3 orders of magnitude more sensitive to T-violating interactions than Hg-199, which currently sets the most stringent limits in the nuclear sector. Recently, we have succeeded in transferring Ra-226 atoms from a MOT into an optical dipole trap formed by a fiber laser beam at 1550 nm. For the EDM measurement, the cold atoms will be moved into the neighboring vacuum chamber inside magnetic shields where a pair of electrodes apply a 10 kV cm-1electric field. This work is supported by DOE, Office of Nuclear Physics under contract No. DE-AC02-06CH11357.

Trimble, W. L.; Sulai, I. A.; Parker, R. H.; Bailey, K.; Greene, J. P.; Holt, R. J.; Korsch, W.; Lu, Z.-T.; Mueller, P.; O'Connor, T. P.; Singh, J.

2010-03-01

464

Micro ultrasonic machining and self-aligned multilayer machining\\/assembly technologies for 3D micromachines  

Microsoft Academic Search

Micro ultrasonic machining (micro-USM) is proposed for the fabrication of 3D microstructures with high aspect ratios. The combination of WEDG and EDM provides a capability of making co-axial microtools for USM and thereafter, microholes as small as 15 ?m in diameter and a variety of high-aspect-ratio microstructures have been achieved for the first time. Also in this paper a 3D

Xi-Qing Sun; T. Masuzawa; M. Fujino

1996-01-01

465

Autoionization of HfF for an electron EDM search  

Microsoft Academic Search

The ^3delta1 state of HfF^+ has been proposed as a candidate for the search for an electron electric dipole moment (eEDM). Neutral HfF molecules are created upon laser ablation of a Hf target in the presence of Ar + 1%SF6, and cooled rotationally via supersonic expansion. The neutral molecules are optically excited with two photons to an autoionizing state, from

Huanqian Loh; Russell Stutz; Matthew Grau; Eric Cornell

2010-01-01

466

Demonstration Cold Atom Fountain Electron Electric Dipole Moment (EDM) Experiment  

Microsoft Academic Search

A demonstration cold-atom-fountain electron EDM experiment has been operated at LBNL. The apparatus is free of static magnetic fields (B < 1 nT) which reduces sensitivity to motional magnetic field effects. Electric-field quantization, state preparation and detection in field-free regions, fractional-cycle pulses, active motional magnetic field nulling, multiple-quantum transitions, and web based, unattended operation of the experiment will be discussed.

Harvey Gould; Jason M. Amini; Charles T. Munger

2006-01-01

467

Progress Towards an Electron EDM Search Using Trapped Molecular Ions  

Microsoft Academic Search

A sample of trapped molecular ions can provide large effective electric fields and long electron spin coherence times in the search for a permanent electron electric dipole moment (EDM). We plan to use the ^3delta1 state of trapped HfF^+ in this search. The ^3delta1 state should yield effective internal fields of 10 V\\/cm and should be easily polarized in 1

Laura Sinclair; Huanqian Loh; Russell Stutz; Eric Cornell

2009-01-01

468

Feasibility demonstration of using wire electrical-discharge machining, abrasive flow honing, and laser spot welding to manufacture high-precision triangular-pitch Zircaloy-4 fuel-rod-support grids  

SciTech Connect

Results are reported supporting the feasibility of manufacturing high precision machined triangular pitch Zircaloy-4 fuel rod support grids for application in water cooled nuclear power reactors. The manufacturing processes investigated included wire electrical discharge machining of the fuel rod and guide tube cells in Zircaloy plate stock to provide the grid body, multistep pickling of the machined grid to provide smooth and corrosion resistant surfaces, and laser welding of thin Zircaloy cover plates to both sides of the grid body to capture separate AM-350 stainless steel insert springs in the grid body. Results indicated that dimensional accuracy better than +- 0.001 and +- 0.002 inch could be obtained on cell shape and position respectively after wire EDM and surface pickling. Results on strength, corrosion resistance, and internal quality of laser spot welds are provided.

Horwood, W.A.

1982-05-01

469

Preliminary Measurements for an Electron EDM Experiment in Thorium Monoxide  

NASA Astrophysics Data System (ADS)

The ACME collaboration aims to measure the eEDM via Ramsey spectroscopy of a cryogenic beam of ThO molecules in their metastable H state. This thesis describes the launch of this new experimental effort. A set of diode lasers has been built to address all the necessary ThO transitions. The laser frequencies were stabilized to a stable reference laser via a Fabry-Perot transfer cavity. A measurement of the magnetic dipole moment of the H state has been performed that is complementary to a previous measurement by the collaboration. This value is important for determining the sensitivity of the H state to magnetic fields, which can be a source of noise and systematic errors in the eEDM measurement. Experimental efforts to prepare the coherent superposition of the M=+/-1 Zeeman sublevels in the H, J=1 state that is the starting point of the eEDM experiment using transitions to the G state resulted in a better understanding of transitions between O-doublet states in an electric field. This led to a new technique for normalizing out shot-to-shot fluctuations in the molecular beam flux, which has also been demonstrated experimentally.

Gurevich, Yulia Vsevolodovna

470

Cryogenic Design for the nEDM Experiment  

NASA Astrophysics Data System (ADS)

The neutron electric dipole moment (nEDM) measurement proposed for the Spallation Neutron Source (SNS) will provide a precision test of time reversal symmetry. Lowering the upper limit on the nEDM, currently 10-26 e.cm, by a factor of 100 would test proposed extensions to the Standard Model. Thermal neutrons from the SNS will be trapped as ultracold neutrons in two 2.2 liter cells filled with superfluid ^4He at 0.45 K. Polarized ^3He atoms dissolved into the ^4He will serve as co-magnetometers. A large dilution refrigerator (DR) will cool the cells and a surrounding 1000 liter volume of liquid helium. Transporting the ^3He to and from the cells via heat flush, and the large diameter tubes that connect volumes of superfluid liquid helium at T <=0.5 K to 4.2 K and above cause significant heat loads on the DR. We have developed thermal models to estimate these heat loads and guide the design of the DR heat exchangers. Previous theoretical and experimental results indicate that large heat flows occur due to superfluid film creep up the tubes and reflux of evaporated gas at higher temperatures. We have prepared an experiment to measure this effect at temperatures relevant to the nEDM experiment.

Kendellen, David; Haase, David; Huffman, Paul

2012-03-01

471

Manufacturing process applications team (MATEAM). [technology transfer in the areas of machine tools and robots  

NASA Technical Reports Server (NTRS)

The transfer of NASA technology to the industrial sector is reported. Presentations to the machine tool and robot industries and direct technology transfers of the Adams Manipulator arm, a-c motor control, and the bolt tension monitor are discussed. A listing of proposed RTOP programs with strong potential is included. A detailed description of the rotor technology available to industry is given.

1979-01-01

472

Copper wire bonding process in leaded packages with zero loss in quality, capacity, scrap & machine efficiency  

Microsoft Academic Search

For the past few years, acceptance and implementation of copper wire has grown from optional to mandatory, especially after gold price increased triple for past 5 years. However, there are many companies still not able to achieve desirable performance, especially without trading off other performance indices such as quality, capacity, scrap or machine efficiency. The copper wire has two fundamental

Tan Chee Eng

2011-01-01

473

SOLAR ACTIVITY DETECTION AND PREDICTION USING IMAGE PROCESSING AND MACHINE LEARNING TECHNIQUES  

E-print Network

TECHNIQUES by Gang Fu The objective of the research in this dissertation is to develop the methods have great influence on the near earth environment. The research presented in this dissertation covers AND MACHINE LEARNING TECHNIQUES by Gang Fu A Dissertation Submitted to the Faculty of New Jersey Institute

474

Prospects for Testing Standard Model (SM) Extensions with Electron Electric Dipole Moment (EDM) Experiments  

Microsoft Academic Search

Split SUSY and other SM extensions with new sources of CP violation allow electron EDMs that approach the present experimental limits. A new generation of laboratory experiments using laser-cooled atoms is expected to push back those limits, further constraining theory or discovering new physics. A demonstration laser-cooled-atom fountain electron EDM experiment operating at LBNL will be described and the EDM

Harvey Gould; Jason M. Amini; Charles T. Munger

2006-01-01

475

Intelligent Machines in the 21st Century: Automating the Processes of Inference and Inquiry  

NASA Technical Reports Server (NTRS)

The last century saw the application of Boolean algebra toward the construction of computing machines, which work by applying logical transformations to information contained in their memory. The development of information theory and the generalization of Boolean algebra to Bayesian inference have enabled these computing machines. in the last quarter of the twentieth century, to be endowed with the ability to learn by making inferences from data. This revolution is just beginning as new computational techniques continue to make difficult problems more accessible. However, modern intelligent machines work by inferring knowledge using only their pre-programmed prior knowledge and the data provided. They lack the ability to ask questions, or request data that would aid their inferences. Recent advances in understanding the foundations of probability theory have revealed implications for areas other than logic. Of relevance to intelligent machines, we identified the algebra of questions as the free distributive algebra, which now allows us to work with questions in a way analogous to that which Boolean algebra enables us to work with logical statements. In this paper we describe this logic of inference and inquiry using the mathematics of partially ordered sets and the scaffolding of lattice theory, discuss the far-reaching implications of the methodology, and demonstrate its application with current examples in machine learning. Automation of both inference and inquiry promises to allow robots to perform science in the far reaches of our solar system and in other star systems by enabling them to not only make inferences from data, but also decide which question to ask, experiment to perform, or measurement to take given what they have learned and what they are designed to understand.

Knuth, Kevin H.

2003-01-01

476

Femtosecond laser ablation properties of transparent materials: impact of the laser process parameters on the machining throughput  

NASA Astrophysics Data System (ADS)

High average power, high repetition rate femtosecond lasers with ?J pulse energies are increasingly used for bio-medical and material processing applications. With the introduction of femtosecond laser systems such as the SpiritTM platform developed by High Q Lasers and Spectra-Physics, micro-processing of solid targets with femtosecond laser pulses have obtained new perspectives for industrial applications [1]. The unique advantage of material processing with subpicosecond lasers is efficient, fast and localized energy deposition, which leads to high ablation efficiency and accuracy in nearly all kinds of solid materials. The study on the impact of the laser processing parameters on the removal rate for transparent substrate using femtosecond laser pulses will be presented. In particular, examples of micro-processing of poly-L-lactic acid (PLLA) - bio-degradable polyester and XensationTM glass (Schott) machined with SpiritTM ultrafast laser will be shown.

Matylitsky, V. V.; Hendricks, F.; Aus der Au, J.

2013-03-01

477

Effect on the electron EDM due to abelian gauginos in SUSY extra U(1) models  

E-print Network

The electric dipole moment of an electron (EDME) is investigated in the supersymmetric extra U(1) models. Neutralino sector is generally extended in these models and then the neutralino contribution will be important for the analysis of the EDME. Kinetic term mixings of abelian gauginos are taken into account in our analysis. Numerical results for the extra U(1) models show that the EDME can be affected by the extra U(1) in a certain range of soft supersymmetry breaking parameters even if the extra U(1) gauge boson is heavy. The EDME may be a clue to find an extended gauge structure in the supersymmetric models.

Daijiro Suematsu

1997-05-24

478

Machine Vision  

NSDL National Science Digital Library

An overview of a generic image-based machine vision system is provided on this Web site (1). The tutorial describes the main components of such a system, how its accuracy is measured, and what scientific and industrial applications benefit from machine vision. A more technical perspective of machine vision technology is given in an online publication of the Automated Imaging Association (2). Monthly feature articles discuss breaking issues related to machine vision, and several technical papers can be downloaded, which are sorted into categories such as three dimensional imaging and nanotechnology. Researchers from the MIT's Artificial Intelligence Laboratory (3) are investigating how to enable a computer to interpret visual and audio signals from its human user. By using machine perception systems to track the user's gaze, for example, the computer could ascertain the focus of the user's attention, thereby facilitating interaction between the human and the computer. The project's homepage includes numerous research papers, as well as video demonstrations of some of its systems. Machine vision is also finding its way into vehicles. A March 2003 news article (4) highlights a field test in Michigan of a collision avoidance system that uses, among other things, machine vision to warn drivers that they are approaching a slower or stopped object too quickly. The 3D Computer Vision Group at Carnegie Mellon University (5) is involved in several projects, including three dimensional object recognition and humanoid robot vision. Many of the group's recent publications are available for download. NASA's Mars Exploration Rovers, the second of which was launched in July 2003, have vision systems that will let them safely navigate rough terrain. These systems are described in this conference paper (6), including specifics of the stereo vision algorithm and insights into future missions. A new implementation of machine vision comes from a former researcher from Cambridge University. His shape recognition system, which is detailed in this news article (7), is reportedly much more related to human visual processes than existing techniques. For additional developments related to this evolving technology, Machine Vision News (8) has information about worldwide research and new applications of machine vision systems.

Leske, Cavin.

479

Extreme Kicking Machine  

NSDL National Science Digital Library

In this design challenge activity follow up to "Kicking Machine", learners add a hands-free feature to their Kicking Machine. Learners modify their kicking machine to have it either release the pendulum or rubber band while standing three feet away or have it automatically feed balls into the kicking machine, one after another. They must figure out how to integrate the new feature into the existing structure and use the design process to make sure the modified kicking machine works properly. Educators can use this activity to demonstrate simple machines and kinetic/potential energy.

2012-08-20

480

Drilling mud cleaning machine  

Microsoft Academic Search

This patent describes a multiple-function cleaning, desilting and desanding machine for cleaning drilling muds which contain unwanted solid waste materials entrained during drilling processes. The machine comprises: supportive frame means adapted to be disposed upon a supportive surface for securely positioning the machine at a selected drilling site; a cyclone chamber having means for receiving dirty drilling mud from a

W. L. Spruiell; J. L. Spruiell

1987-01-01

481

Review on ultrasonic machining  

Microsoft Academic Search

Ultrasonic machining is of particular interest for the cutting of non-conductive, brittle workpiece materials such as engineering ceramics. Unlike other non-traditional processes such as laser beam, and electrical discharge machining, etc., ultrasonic machining does not thermally damage the workpiece or appear to introduce significant levels of residual stress, which is important for the survival of brittle materials in service. The

T. B. Thoe; D. K. Aspinwall; M. L. H. Wise

1998-01-01

482

Investigation on the preparation and machinability of the B 4C\\/BN nanocomposites by hot-pressing process  

Microsoft Academic Search

The machinable B4C\\/BN nanocomposites were fabricated by the hot-pressing process using the B4C\\/BN nanocomposite powders at 1850C for 1h under the pressure of 30MPa. The nanocomposite powders with the microstructure of micro-sized B4C particles coated with amorphous nano-sized BN particles were prepared by the chemical reaction of H3BO3 and CO(NH2)2 on the surface of B4C particles at high temperature. Then

Tao Jiang; Zhihao Jin; Jianfeng Yang; Guanjun Qiao

2009-01-01

483

Search for a Neutron Electric Dipole Moment at the SNS Brad Filippone (Caltech) for the nEDM@SNS collaboration  

E-print Network

EDM@SNS collaboration The discovery of a neutron EDM (Electric Dipole Moment) above the Standard Model background, which in the atom it can be used as a sensitive magnetic field monitor. High densities of trapped ultra

484

Distributed processing (DP) based e-beam lithography simulation with long range correction algorithm in e-beam machine  

NASA Astrophysics Data System (ADS)

As the design rule with wafer process is getting smaller down below 50nm node, the specification of CDs on a mask is getting more tightened. Therefore, more tight and accurate E-Beam Lithography simulation is highly required in these days. However, in reality most of E-Beam simulation cases, there is a trade-off relationship between the accuracy and the simulation speed. Moreover, the necessity of full chip based simulation has been increasing in order to estimate more accurate mask CDs based on real process condition. Therefore, without consideration of long range correction algorithm such as fogging effect and loading effect correction in E-beam machine, it would be impossible and meaningless to pursue the full chip based simulation. In this paper, we introduce a breakthrough method to overcome the obstacles of E-Beam simulation. In-house E-beam simulator, ELIS (E-beam LIthography Simulator), has been upgraded to solve these problems. First, DP (Distributed Processing) strategy was applied to improve calculation speed. Secondly, the long range correction algorithm of E-beam machine was also applied to compute intensity of exposure on a full chip based (Mask). Finally, ELIS-DP has been evaluated possibility of expecting or analyzing CDs on full chip base.

Ki, Won-Tai; Choi, Ji-Hyeon; Kim, Byung-Gook; Woo, Sang-Gyun; Cho, Han-Ku

2008-05-01

485

Machinability of Austempered Ductile Iron (ADI) Produced by Integrated Green Technology of Continuous Casting-Heat Treatment Processes  

SciTech Connect

This study presents the novel processing technique known as continuous casting-heat treatment processes to produce Austempered Ductile Iron (ADI) which is a new class of ductile iron. ADI is characterized by improved mechanical properties but has low machinability as compared to other cast irons and steel of similar strength. The novel technique is developed by the integration of casting (in die casting) and heat treatment processes in foundry to save cost energy and time. Specimens just after casting were austenitized at 930 deg. C for 90 min and then austempered in fluidized bed at 380 deg. C for 90 and 120 min. Hence, the effect of austempering time on the morphology of retained austenite and mechanical properties of the material were examined and compared with conventionally produced ADI. Drilling tests were then carried out to evaluate the machinability of ADI in terms of cutting forces, chip micro-hardness, chip morphology and surface roughness. The mechanical properties of ADI austempered for 120 min have found to be better as compare to the ADI austempered for 90 min.

Meena, A.; El Mansori, M.; Ghidossi, P. [Arts et Metiers ParisTech, LMPF-EA 4106, Rue Saint Dominique, BP 508, 51006, Chalons-en-Champagne, Cedex (France)

2011-01-17

486

Machinability of Austempered Ductile Iron (ADI) Produced by Integrated Green Technology of Continuous Casting-Heat Treatment Processes  

NASA Astrophysics Data System (ADS)

This study presents the novel processing technique known as continuous casting-heat treatment processes to produce Austempered Ductile Iron (ADI) which is a new class of ductile iron. ADI is characterized by improved mechanical properties but has low machinability as compared to other cast irons and steel of similar strength. The novel technique is developed by the integration of casting (in die casting) and heat treatment processes in foundry to save cost energy and time. Specimens just after casting were austenitized at 930 C for 90 min and then austempered in fluidized bed at 380 C for 90 and 120 min. Hence, the effect of austempering time on the morphology of retained austenite and mechanical properties of the material were examined and compared with conventionally produced ADI. Drilling tests were then carried out to evaluate the machinability of ADI in terms of cutting forces, chip micro-hardness, chip morphology and surface roughness. The mechanical properties of ADI austempered for 120 min have found to be better as compare to the ADI austempered for 90 min.

Meena, A.; El Mansori, M.; Ghidossi, P.

2011-01-01

487

Mean Machines.  

ERIC Educational Resources Information Center

Suggests scales as alternative representations of numerical concepts and operations that can be used as arithmetic-mean machines, adding machines, multiplication machines, and geometric-mean machines. (ASK)

Flores, Alfinio

1998-01-01

488

High-speed micro electrode tool fabrication by a twin-wire EDM system  

Microsoft Academic Search

This paper describes a new machining process which combines twin-electro-wire together with two electro discharge circuits to rapidly fabricate micro electrode tools. The results show that transistor electro discharge and RC electro discharge circuits coexist to fabricate micro tools with rough and finish machining both on the same machine. Compared to conventional wire electro discharge grinding (WEDG) technology, a twin-wire

Dong-Yea Sheu

2008-01-01

489

Electrical discharge machining of type-N(f) microwave connectors  

SciTech Connect

A particular out-of-specification mechanical dimension on Type-N(f) [Type-N(female)] microwave connectors sometimes disqualifies otherwise perfectly acceptable microwave devices from being used in calibration systems. The Miniature Machining Group at Sandia National Laboratories applied a technique called Electrical Discharge Machining (EDM) to quickly and economically machine these devices without disassembly. In so doing, they facilitated the use of existing components without the need to purchase new devices. The technique also improves an uncertainty of calibration known as Mismatch Uncertainty by optimizing the reflection coefficient of the calibration test port. This effects a reduction in overall calibration uncertainties.

Haushalter, R.J.

1996-07-01

490

A Contact-Imaging Based Microfluidic Cytometer with Machine-Learning for Single-Frame Super-Resolution Processing  

PubMed Central

Lensless microfluidic imaging with super-resolution processing has become a promising solution to miniaturize the conventional flow cytometer for point-of-care applications. The previous multi-frame super-resolution processing system can improve resolution but has limited cell flow rate and hence low throughput when capturing multiple subpixel-shifted cell images. This paper introduces a single-frame super-resolution processing with on-line machine-learning for contact images of cells. A corresponding contact-imaging based microfluidic cytometer prototype is demonstrated for cell recognition and counting. Compared with commercial flow cytometer, less than 8% error is observed for absolute number of microbeads; and 0.10 coefficient of variation is observed for cell-ratio of mixed RBC and HepG2 cells in solution. PMID:25111497

Huang, Xiwei; Guo, Jinhong; Wang, Xiaolong; Yan, Mei; Kang, Yuejun; Yu, Hao

2014-01-01

491

Research of the micro-EDM discharge state detection method based on matlab Fuzzy control  

Microsoft Academic Search

Based on the rules which summed up of the micro-EDM discharge state, the paper makes use of Fuzzy control technology to detect discharge state. It mainly uses matlab Fuzzy module to design discharge state detection Fuzzy controller, and get a good identification results through simulating. Compared with the traditional detection methods, it gains better results in the micro-hole EDM experiment

Yang Yang; Mei Yanghan; He Tian

2010-01-01

492

Multiconfiguration Dirac-Hartree-Fock calculations of EDM for Ra, Hg, Yb  

NASA Astrophysics Data System (ADS)

Using multiconfiguration Dirac-Hartree-Fock (MCDHF) method, we calculated the atomic electric dipole moment (EDM) for Ra, Hg, Yb, arising from nuclear Schiff moment, (P,T)-odd electron-nucleon interactions, and interaction of electron EDM with nuclear electromagnetic field.

Gaigalas, Gediminas; Biero?, Jacek; Radi?t?, Laima

2014-04-01

493