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1

AFM surface imaging of AISI D2 tool steel machined by the EDM process  

Microsoft Academic Search

The surface morphology, surface roughness and micro-crack of AISI D2 tool steel machined by the electrical discharge machining (EDM) process were analyzed by means of the atomic force microscopy (AFM) technique. Experimental results indicate that the surface texture after EDM is determined by the discharge energy during processing. An excellent machined finish can be obtained by setting the machine parameters

Y. H. Guu

2005-01-01

2

Performance Evaluation of Electrical Discharge Machining (EDM) Process Using Cryogenically Cooled Electrode  

Microsoft Academic Search

This article describes a study on the cooling effect on copper electrode while electrical discharge machining (EDM) M2 grade high speed steel workpiece. To evaluate the machinability, electrode wear ratio (EWR) and surface roughness (SR) were the two responses observed. Discharge current, pulse on time, duty cycle, and gap voltage were the controllable process parameters. It was found that EWR

Vineet Srivastava; Pulak M. Pandey

2012-01-01

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

Processing of Zirconium-Based Bulk Metallic Glass (BMG) Using Micro Electrical Discharge Machining (Micro-EDM)  

Microsoft Academic Search

A zirconium-based bulk metallic glass was machined by micro electrical discharge machining (micro-EDM) to demonstrate its feasibility under discharge energies typical of the microregime. Furthermore, input energies of 13.4 µJ and 0.9 µJ, and three different tool electrodes, namely, tungsten rod electrode, copper, and brass tube electrodes were employed to elucidate the effects of different machining conditions on the machined surface roughness,

Swee Hock Yeo; Peng Cheong Tan; Erwin Aligiri; Shu Beng Tor; Ngiap Hiang Loh

2009-01-01

5

Development of a combined machining method using electrorheological fluids for EDM  

Microsoft Academic Search

The objective of this study is to develop a new combined technology of electrical discharge machining (EDM) with polishing by using electrorheological (ER) fluid as working fluid. The surface of the work-piece after EDM has a recast layer with many micro-craters and cracks. Therefore, the polishing process is usually required after EDM for the molds applied on computer, communication and

Y. Y. Tsai; C. H. Tseng; C. K. Chang

2008-01-01

6

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

7

A correlation between machining parameters and machinability in EDM  

Microsoft Academic Search

These investigations were carried out to determine possible correlations between the EDM machining parameters (pulse on, current) and the machineability components (stock removal, electrode wear, overcut, surface finish and surface integrity). The surface integrity of the component depends on its conformity to tolerance, its surface finish and the metallurgical subsurface characteristics. The present work indicates a correlation between the overcut

S. K. BHATTACHARYYA; M. K. EL-MENSHAWY; S. GARBER; J. WALLBANK

1981-01-01

8

Micro-hole machining using micro-EDM combined with electropolishing  

Microsoft Academic Search

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

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

2006-01-01

9

Parametric curve machining of a CNC milling EDM  

Microsoft Academic Search

A buffered digital differential analyzer (BDDA) algorithm in a computerized numerical controller (CNC) performs milling electric discharge machining (milling EDM'ing) of a curve constructed from a sequence of segments using a traditional computer-aided manufacturing (CAM) system. The proposed algorithm interpolates more than one segment in a sampling interval and supports the effective machining of a parametric curve when the electrode

Yih-Fang Chang; Rong-Chi Hong

2005-01-01

10

Selection of EDM Process Parameters Using Biogeography-Based Optimization Algorithm  

Microsoft Academic Search

Amongst the nontraditional machining processes, electric discharge machining (EDM) is considered to be one of the most important processes for machining intricate and complex shapes in various electrically conductive materials, including high-strength, temperature-resistant (HSTR) alloys, especially in aeronautical and automotive industries. For achieving the best performance of the EDM process, it is imperative to carry out parametric design which involves

Rajarshi Mukherjee; Shankar Chakraborty

2012-01-01

11

EDM Machine Modified For Micro Drilling In DAC Experiments  

NASA Astrophysics Data System (ADS)

A JOEMARS Electric discharge machine (EDM) has been modified for micro drilling of gasket holes for high pressure experiments using a diamond anvil cell. We were able to use normal tungsten carbide drill bits that are used for drilling micro holes manually with the EDM. The drilled holes were free of burr formation and had a nice surface finish.

Lonappan, Dayana; Shekar, N. V. Chandra; Sundaram, L. M.; Edwin, T.; Sahu, P. Ch.

2011-07-01

12

Electrical Discharge Machining (EDM) Characteristics Associated with Electrical Discharge Energy on Machining of Cemented Tungsten Carbide  

Microsoft Academic Search

In this investigation, cemented tungsten carbides graded K10 and P10 were machined by electrical discharge machining (EDM) using an electrolytic copper electrode. The machining parameters of EDM were varied to explore the effects of electrical discharge energy on the machining characteristics, such as material removal rate (MRR), electrode wear rate (EWR), and surface roughness. Moreover, the effects of the electrical

Yan-Cherng Lin; Yuan-Feng Chen; Ching-Tien Lin; Hsinn-Jyh Tzeng

2008-01-01

13

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.

14

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

SciTech Connect

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 the contour of the workpiece after roughing in order to further process and recognize the image for determining the residual. This facilitates the on-machine error detection and compensation re-machining. The micro workpiece and electrode are not repositioned during machining. A fabrication for a micro probe of 30-{mu}m diameter is rapidly machined and verified successfully. Based on the proposed technique, on-machine measurement with AOI has been realized satisfactorily.

Chen Shuntong [Department of Mechatronic Technology, National Taiwan Normal University (China); Yang Hongye [Department of Industrial Education, National Taiwan Normal University (China)

2011-01-17

15

Developments in electric power supply configurations for electrical-discharge-machining (EDM)  

Microsoft Academic Search

The electric discharge machining (EDM) process provides one of the best alternatives, or sometimes the only alternative, to machine a growing number of high-strength and corrosion-and-wear-resistant materials. It is based on the principle of erosion of metals by an interrupted electric spark. The power supply design and configuration requirements for producing the desired \\

B. Sen; N. Kiyawat; P. K. Singh; S. Mitral; J. H. Ykmd; P. Purkait

2003-01-01

16

Effects of finishing in abrasive fluid machining on microholes fabricated by EDM  

Microsoft Academic Search

This research investigated the effects of the fine-finishing process on microholes in abrasive fluid machining (AFM). Microholes\\u000a on stainless steel (SUS 304) and titanium alloy (Ti-6Al-4V) plates were fabricated using a deep drilling machine of electrical\\u000a discharge machining (EDM) prior to AFM. In the experiment, the Taguchi method was adopted to explore the effects of the machining\\u000a parameters associated with

Yan-Cherng Lin; Han-Ming Chow; Biing-Hwa Yan; Hsinn-Jyh Tzeng

2007-01-01

17

Selection of EDM Process Parameters Using Biogeography-Based Optimization Algorithm  

Microsoft Academic Search

Amongst the non-traditional machining processes, electric discharge machining (EDM) is considered to be one of the most important processes for machining intricate and complex shapes in various electrically conductive materials, including high-strength, temperature-resistant (HSTR) alloys, especially in aeronautical and automotive industries. For achieving the best performance of the EDM process, it is imperative to carry out parametric design which involves

Rajarshi Mukherjee; Shankar Chakraborty

2011-01-01

18

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 µm 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

19

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 µm Rmax before grinding to 0.69 µm Rmax after electropolishing.

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

2006-08-01

20

Microanalysis of debris formed during electrical discharge machining (EDM)  

Microsoft Academic Search

The present investigation attempts to focus on the influence of EDM energy input on the structure and composition of the debris\\u000a that forms during machining. An indigenously prepared ZrB2-Cu composite and mild steel plate were used as tool and workpiece (WP) material for the present study. The machining was\\u000a carried out in a kerosene medium. The composition analysis of different

Asit Kumar Khanra; L. C. Pathak; M. M. Godkhindi

2007-01-01

21

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

22

Electrical Discharge Machining (EDM) Gun Barrel Bore and Rifling Feasibility Study.  

National Technical Information Service (NTIS)

A 12-month program was conducted to advance the technology of the Electrical Discharge Machining (EDM) process to be applicable to the stringent requirements of gun barrel boring and rifling. The type of barrels employed in the test were .220 swift gun ba...

R. M. Greene

1974-01-01

23

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

24

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

25

3D surface characterisation of electropolished EDMed surface and quantitative assessment of process variables using Taguchi Methodology  

Microsoft Academic Search

The electro discharge machining (EDM) process produces surfaces that require some form of finishing operation. This is done in order to improve the surface texture and appearance of the component’s surface. However, it is also desirable to remove the white uppermost recast layer (produced by the EDM process) so as to improve the functional performance of the surface. Electropolishing or

H Ramasawmy; L Blunt

2002-01-01

26

Optimization of EDM process for multiple performance characteristics using Taguchi method and Grey relational analysis  

Microsoft Academic Search

Electrical discharge machining (EDM) is one of the most extensively used non-conventional material removal processes. The\\u000a Taguchi method has been utilized to determine the optimal EDM conditions in several industrial fields. The method, however,\\u000a was designed to optimize only a single performance characteristic. To remove that limitation, the Grey relational analysis\\u000a theory has been used to resolve the complicated interrelationships

Jong Hyuk Jung; Won Tae Kwon

2010-01-01

27

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 µm Rmax before finishing to 0.58 µm 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

28

Experimental study of micro-EDM machining performances on silicon wafer  

Microsoft Academic Search

The micro-EDM silicon machining performances have been stud on a highly doped P-type silicon wafer. To demonstrate and to emphasize the silicon micro-EDM, one kind of stainless steel is machine das a reference material. Both materials are sparked with specific sparking energy in micro-Joule energy range and machining characteristics such as material removal mechanism, cutting rate, relative electrode wear ratio

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

2000-01-01

29

EDM machinability and frictional behaviour of ZrO2-TiCN composites  

Microsoft Academic Search

Zirconia composites with 40 vol% TiCN were proven to be feasible for wire electrical discharge machining (EDM). Optimum material removal rates were assessed. The material removal mechanisms were elucidated. Gradually finer EDM regimes improved the surface quality considerably. Dry sliding frictional characteristics of ZrO2-TiCN against WC-Co cemented carbide were evaluated.

Koenraad Bonny; Patrick De Baets; Jozef Vleugels; Arezou Salehi; Omer Van der Biest; Bert Lauwers; Weidong Liu

2008-01-01

30

Modeling and analysis of the rapidly resolidified layer of SG cast iron in the EDM process through the response surface methodology  

Microsoft Academic Search

The rapidly resolidified layer is formed by the re-solidification of residual molten material on the machined surface during the electric discharge machining (EDM) process. This paper presents a systematic methodology for modeling and analysis of the rapidly resolidified layer of spheroidal graphite (SG) cast iron in the EDM process using the response surface methodology (RSM). The factors of second phase

Ko-Ta Chiang; Fu-Ping Chang; De-Chang Tsai

2007-01-01

31

Comparative study of different dielectrics for micro-EDM performance during microhole machining of Ti6Al4V alloy  

Microsoft Academic Search

In microelectrodischarge machining (micro-EDM), dielectric plays an important role during machining operation. The machining\\u000a characteristics are greatly influenced by the nature of dielectric used during micro-EDM machining. Present paper addresses\\u000a the issues of micro-EDM utilizing different types of dielectrics such as kerosene, deionized water, boron carbide (B4C) powder suspended kerosene, and deionized water to explore the influence of these dielectrics

G. Kibria; B. R. Sarkar; B. B. Pradhan; B. Bhattacharyya

2010-01-01

32

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

33

Insight into fundamental aspects of the EDM process using multidischarge numerical simulation  

Microsoft Academic Search

The electrical discharge machining (EDM) process is a popular non-traditional machining process, but, although it is widely\\u000a used in industry, there is still a lack of scientific knowledge about its fundamentals. This paper discusses some aspects\\u000a of the discharge process at the sight of the results obtained with a previously developed thermal model, which is capable\\u000a of simulating the superposition

Borja Izquierdo; José Antonio Sánchez; Naiara Ortega; Soraya Plaza; Iñigo Pombo

2011-01-01

34

Performance analysis of EDM electrode fabricated by localized electrochemical deposition for micro-machining of stainless steel  

Microsoft Academic Search

Electrical discharge machining (EDM) is an important and widely used process for the fabrication of complex three-dimensional\\u000a structure of micro-tools, micro-components, and parts with micro-feature. It allows high precision, low setup cost, large\\u000a freedom of design, and good surface quality. However, in order to produce different varieties of high-accuracy structures\\u000a on machine, microelectrode fabrication is necessary so as to reduce

Mohammad Ahsan Habib; Mustafizur Rahman

2010-01-01

35

Process planning and electrode wear compensation for 3D micro-EDM  

Microsoft Academic Search

This paper presents a novel multi-cut process planning method and a new electrode wear compensation method based on a machine\\u000a vision system for three-dimensional (3D) micro-electrical discharge machining (micro-EDM). Front wear and corner wear of tool\\u000a electrode can be measured and compensated in a direct manner by the vision system’s image processing software capabilities.\\u000a Experiments have shown that corner wear

Mu-Tian Yan; Shr-Shiang Lin

2011-01-01

36

A Study on Dry Electrical Discharge Machining Process  

Microsoft Academic Search

This study investigates the characteristics of the dry electrical discharge machining (EDM) process. Dry wire EDM experiments of thin workpieces were conducted in air, which was used as the dielectric fluid. The relationships among spark cycle (T), spark on-time (Ton), air flow, thickness of workpieces and work material were studied in the cases of wet and dry EDM conditions. The

Sang Won Lee; Young Seok Oh

2008-01-01

37

EDM machinability and frictional behavior of ZrO 2 -WC composites  

Microsoft Academic Search

Zirconium dioxide (ZrO2)-based composites with WC addition are demonstrated to be suitable for electrical discharge machining (EDM) in deionized\\u000a water. ZrO2-based composites with 40 vol. % WC, obtained from distinctive WC powder sources, were produced in order to derive correlations\\u000a between material removal rate (MRR), surface finish, wire EDM parameters and material properties. Dry reciprocating sliding\\u000a experiments on wire-electrical discharge

K. Bonny; P. De Baets; J. Vleugels; A. Salehi; O. Van der Biest; B. Lauwers; W. Liu

2009-01-01

38

Cylindrical Wire Electrical Discharge Machining Process Development  

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. 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

Jun Qu; Albert J. Shih; Ron O. Scattergood; Samuel B. McSpadden

39

Experimental study of micro-EDM machining performances on silicon wafer  

NASA Astrophysics Data System (ADS)

The micro-EDM silicon machining performances have been stud on a highly doped P-type silicon wafer. To demonstrate and to emphasize the silicon micro-EDM, one kind of stainless steel is machine das a reference material. Both materials are sparked with specific sparking energy in micro-Joule energy range and machining characteristics such as material removal mechanism, cutting rate, relative electrode wear ratio and surface quality are examined and analyzed. The thermally induced microcracks are also examined and analyzed using a an optical and a SEM. It is found that for silicon, the micro-EDM material removal mechanism is not completely similar to conventional metal micro-EDM; besides melting and evaporation there is a significant contribution from thermal spallation, which is a kind of direct mechanical material damage without melting. This paper also present that microcrack generation is not only relate to the sparking energy but also has a close relationship with the silicon crystal lattice. In order to get microcrack free silicon surfaces, the sparking energy should be controlled to low levels, which are much lower than the voltage levels used in metal micro-EDM. All in all, thermal spalling should be reduced as much as possible, to obtain smooth and crack free machined surfaces.

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

2000-08-01

40

INVESTIGATING THE EFFECTS OF EDM PARAMETERS ON SURFACE INTEGRITY, MRR AND TWR IN MACHINING OF Ti–6Al–4V  

Microsoft Academic Search

Ti–6Al–4V is a kind of difficult-to-cut material with poor machinability by traditional machining methods, while electrical discharge machining (EDM) is suitable for machining titanium alloys. In this paper, three input machining parameters including pulse current, pulse on time and open circuit voltage were changed during EDM tests. To investigate the output characteristics; material removal rate (MRR), tool wear ratio (TWR)

B. Jabbaripour; M. H. Sadeghi; Sh. Faridvand; M. R. Shabgard

2012-01-01

41

An adaptive control system with self-organizing fuzzy sliding mode control strategy for micro wire-EDM machines  

Microsoft Academic Search

This paper aims to develop an adaptive control system for process monitoring, identification, and control in micro wire electrical\\u000a discharge machining (wire-EDM). The proportion of short circuits in the total sparks defined as short circuit ratio is chosen\\u000a as a control parameter for the adaptive control system. Pulse interval of each spark is adjusted in real-time according to\\u000a the discrimination

Mu-Tian Yan

2010-01-01

42

Improvement of machining characteristics of micro-EDM using transistor type isopulse generator and servo feed control  

Microsoft Academic Search

This paper describes the improvement of machining characteristics of micro electrical discharge machining (micro-EDM) using a newly developed transistor type isopulse generator and servo feed control. The RC generator is mainly applied in conventional micro-EDM even though the transistor type isopulse generator is generally more effective for obtaining higher removal rate, because the transistor type generator is unable to generate

Fuzhu Han; Shinya Wachi; Masanori Kunieda

2004-01-01

43

Influence of EDM process parameters in deep hole drilling of Inconel 718  

Microsoft Academic Search

This paper reports on an experimental investigation of small deep hole drilling of Inconel 718 using the EDM process. The\\u000a parameters such as peak current, pulse on-time, duty factor and electrode speed were chosen to study the machining characteristics.\\u000a An electrolytic copper tube of 3 mm diameter was selected as a tool electrode. The experiments were planned using central\\u000a composite design

P. Kuppan; A. Rajadurai; S. Narayanan

2008-01-01

44

Multi-objective optimization of the dry electric discharge machining process  

Microsoft Academic Search

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.

Sourabh K. Saha; S. K. Choudhury

2009-01-01

45

Computational Materials Science and Surface Engineering EDM process optimisation via predicting a controller model  

Microsoft Academic Search

Purpose: Electro-discharge machining is an important manufacture technology in machining difficult-to-cut materials and to shape complicated contours and profiles with high material removal rate, low tool wear and good tolerances. Design\\/methodology\\/approach: In machining of carbon-based materials such as WC-Co and non-oxide ceramics which are growingly used, the complexity and non-linear nature of EDM is a serious problem. EDM is the

R. A. Mahdavinejad

46

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

47

Development of the Cylindrical Wire Electrical Discharge Machining Process  

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. 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

McSpadden

2002-01-01

48

Effect of low-frequency vibration on workpiece in EDM processes  

Microsoft Academic Search

High-frequency vibration aided EDM has become one of the ways to increase material removal rate in EDM process, due to the\\u000a flushing effect caused by vibration. However, utilizing high-frequency vibration, especially in ultrasonic range consumes\\u000a a lot of setup cost. This work presents an attempt to use a low-frequency vibration on workpiece of stainless steel (SS 304)\\u000a during EDM process.

Gunawan Setia Prihandana; Muslim Mahardika; M. Hamdi; Kimiyuki Mitsui

2011-01-01

49

Improvement of Dry EDM Characteristics Using Piezoelectric Actuator  

Microsoft Academic Search

This paper describes improvement of the machining characteristics of dry electrical discharge machining (dry EDM) by controlling the discharge gap distance using a piezoelectric actuator. Dry EDM is a new process characterized by small tool electrode wear, negligible damage generated on the machined surface, and significantly high material removal rate especially when oxygen gas is used. However, the narrow discharge

Masanori Kunieda; Tsutomu Takaya; Shintaro Nakano

2004-01-01

50

Laser machining in die making—a modern rapid tooling process  

Microsoft Academic Search

Laser machining is a new, very flexible process in mould making especially, for the machining of filigree structures. This process is suitable for machining difficult-to-machine materials, like ceramics, carbide and hardened steel with excellent productivity and surface quality. Laser machining provides a number of advantages over the traditional electro discharge machining (EDM) in die making. It eliminates the expensive manufacture

A. Kaldos; H. J. Pieper; E. Wolf; M. Krause

2004-01-01

51

Performance Evaluation of EDM Process Using Cryogenically Cooled Electrode  

Microsoft Academic Search

This paper describes the study about the cooling effect on copper electrode while electrical discharge machining of M2 grade high speed steel workpiece. To evaluate the machinability, electrode wear ratio (EWR) and surface roughness (SR) were the two responses observed. Discharge current, pulse on time, duty cycle and gap voltage were the controllable process parameters. It was found that electrode

Vineet Srivastava; Pulak M. Pandey

2011-01-01

52

Microelectro discharge machining as a technology in micromachining  

Microsoft Academic Search

In recent years, machine facilities for Electro Discharge Machining (EDM) have been dramatically improved. Enormous progress has been obtained with respect to form accuracy and structure precision even in the submicron domain, which qualifies EDM as a technology for microfabrication ((mu) EDM). (Mu) EDM therefore extends the family of existing microtechniques e.g. the LIGA process or silicon surface micromachining. The

Wolfgang Ehrfeld; Heinz Lehr; Frank Michel; Andrej Wolf; Hans-Peter Gruber; Axel Bertholds

1996-01-01

53

Artificial neural network model in surface modification by EDM using tungsten–copper powder metallurgy sintered electrodes  

Microsoft Academic Search

Electro-discharge machining (EDM) is a widely accepted nontraditional machining process used mostly for machining materials\\u000a difficult to machine by conventional shearing process. Surface modification by powder metallurgy sintered tools is an uncommon\\u000a aspect of EDM. Of late, it is being explored by many researchers. In the present paper, attempts have been made to model the\\u000a surface modification phenomenon by EDM

Promod Kumar Patowari; Partha Saha; P. K. Mishra

2010-01-01

54

Near-Dry EDM Milling of Mirror-Like Surface Finish  

Microsoft Academic Search

This study investigates near-dry EDM milling as a finishing process to achieve a mirror-like surface finish. A liquid-gas mist mixture is the dielectric medium delivered through a rotating tubular electrode in the near-dry EDM milling. Near-dry EDM exhibits the advantage of good machining stability and smooth surface finish at low discharge energy input. An EDM power generator is modified by

Jia Tao; Albert J. Shih; Jun Ni

55

Experimental investigation and empirical modeling of the dry electric discharge machining process  

Microsoft Academic Search

Dry electric discharge machining (EDM) is an environment-friendly modification of the oil EDM process in which liquid dielectric is replaced by a gaseous medium. In the current work, parametric analysis of the process has been performed with tubular copper tool electrode and mild steel workpiece. Experiments have been conducted using air as the dielectric medium to study the effect of

Sourabh K. Saha; S. K. Choudhury

2009-01-01

56

Digraph and matrix method to evaluate the machinability of tungsten carbide composite with wire EDM  

Microsoft Academic Search

Machinability aspect is of considerable importance for efficient process planning in manufacturing. Machinability of an engineering\\u000a material may be evaluated in terms of the process output variables like material removal rate, processed surface finish, cutting\\u000a forces, tool life, specific power consumption, etc. In this paper, graph theoretic approach (GTA) is proposed to evaluate\\u000a the machinability of tungsten carbide composite. Material

Kamal Jangra; Sandeep Grover; Felix T. S. Chan; Aman Aggarwal

57

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

58

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

Microsoft Academic Search

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

S. Mitra; G. Paul; S. Sarkar; Nagahanumaiah

2011-01-01

59

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

60

Investigation of EDM characteristics of nickel-based heat resistant alloy  

Microsoft Academic Search

The EDM processing characteristics of one of the nickel-based heat resistant alloys, Hast-elloy-X, were investigated under\\u000a the various EDM conditions and analyzed in terms of surface integrity. This alloy is commonly used as a material for the hot\\u000a gas path component of gas turbines and it is difficult to machine by conventional machining methods. The primary EDM parameter\\u000a which was

Sin Ho Kang; Dae Eun Kim

2003-01-01

61

Experimental Study on Influence of Process Variables on Crater Dimensions in Micro- EDM of ? -Titanium Aluminide  

NASA Astrophysics Data System (ADS)

In the present work the effect of different dielectric mediums in micro-EDM of ?-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.; Nagahanumaiah

2011-01-01

62

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

63

Numerical prediction of heat affected layer in the EDM of aeronautical alloys  

NASA Astrophysics Data System (ADS)

Electrical discharge machining is a popular non-traditional machining process, optimum for accurate machining of complex geometries in hard materials. EDM has been used for decades for machining pieces for the aeronautical industry, but surface integrity, and consequently the reliability of the machined parts have been questioned for long time due to the thermal nature of this machining process. In recent years, efforts have been put on modeling of the EDM process, being thermal modeling of the process one promising alternative. In a previous publication an original model of the EDM process was presented and it was used to predict material removal rate and surface finish for the EDM of steel. In the present article the capability of that modeling tool to characterize discharge properties and to predict recast layer distribution when EDMing an aeronautical alloy will be analyzed. EDM process of Inconel 718 has been studied and discharge properties have been obtained for four different EDM regimes. The capability of the model to reflect the behavior of more energetic regimes is discussed. Gathered information has been used to simulate the evolution of the recast layer generation process. Obtained results have been validated comparing them with experimental measurements, revealing a good correlation between predictions and experimental data. Finally, energetic efficiency of the discharge process has been simulated for the adjusted EDM regimes.

Izquierdo, B.; Plaza, S.; Sánchez, J. A.; Pombo, I.; Ortega, N.

2012-10-01

64

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

65

Surface modification of Al–Zn–Mg alloy by combined electrical discharge machining with ball burnish machining  

Microsoft Academic Search

The study investigated the feasibility of modifying the surface of Al–Zn–Mg 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

66

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

67

Study of 3D Surface Machined on Cemented Carbide by Dry EDM  

Microsoft Academic Search

In dry electric discharge machining of cemented carbide, short circuits frequently occur between work and tool electrodes, disrupting the process. In this study, to increase the efficiency of electric discharge frequency and increase work removal rate, we researched the effects of superposed voltage, ultrasonic vibration, high peak current, and mist supply. As a result, it was found that applying superposed

YU Zhanbo; Jun TAKAHASHI; Nobuhiro NAKAJIMA; Sadao SANO; Masanori KUNIEDA

2005-01-01

68

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 µm 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 µm 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

69

Nontraditional Machining of Beryllium.  

National Technical Information Service (NTIS)

The report deals with electrichemical machining (ECM), chemical milling, and electric-discharge machining (EDM). The general characteristics of these processes and their applications to the processing of beryllium parts are presented and covered in detail...

J. A. Gurklis

1972-01-01

70

EDM surface: Topography, chemistry, and metallurgy.  

National Technical Information Service (NTIS)

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 importan...

J. E. Fuller

1991-01-01

71

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

72

Recast layer removal after electrical discharge machining via Taguchi analysis: A feasibility study  

Microsoft Academic Search

This study explores the feasibility of removing the recast layer (RCL) using etching and mechanical grinding for Ni-based superalloy materials by means of electrical discharge machining (EDM). The EDM process is widely used for machining hard metals and performing specific tasks that cannot be achieved using conventional techniques. The sparks produced during the EDM process melt the metal's surface, which

Che-Chung Wang; Han-Ming Chow; Lieh-Dai Yang; Chun-Te Lu

2009-01-01

73

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

74

Micro-hole Maching of Copper Using the Electrodischarge Machining Process with a Tungsten Carbide Electrode Compared with a Copper Electrode  

Microsoft Academic Search

This paper describes micro-hole machining of a copper plate using the electro-discharge machining (EDM) process. Tungsten\\u000a carbide was selected as the material for the electrode and compared with a copper-electrode. A precision centreless grinding\\u000a process was employed to grind the electrode down to the desired diameter. A series of experiments were performed on a traditional\\u000a EDM machine to investigate the

M.-G. Her; F.-T. Weng

2001-01-01

75

Electrical discharge machining for sharpening diamond disks  

Microsoft Academic Search

Electrical discharge machines have undergone rapid improvements in capability, economical operation, speed and flexibility. In fact, electrical discharge machining (EDM) is now the fourth most popular machining process, selling more than all other processes except milling, turning and grinding. Ninety percent of EDM applications in the world are used to produce molds, stamping dies, extrusion dies, forging dies, tool fixtures

Jesus Doval-Gandoy; Ramón Pasandin; Bernardo Fernandez

2004-01-01

76

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

77

Machining Efficiency Evaluation of Cryogenically Treated Copper Electrode in Additive Mixed EDM  

Microsoft Academic Search

The present experimental investigations have been carried to evaluate machining efficiency with additive powder mixed in dielectric fluid of electrical discharge machining on Inconel 718 with copper and cryogenically treated copper electrodes. Experiments have been conducted to study the effect of input parameters viz polarity, type of electrode, peak current, pulse on time, duty cycle, gap voltage, retract distance and

Anil Kumar; Sachin Maheshwari; Chitra Sharma; Naveen Beri

2012-01-01

78

OBSERVATIONS on CRACKING BEHAVIOR of MICRO ALLOY STEEL in ELECTRIC DISCHARGE MACHINING (EDM)  

Microsoft Academic Search

In this paper, the cracking behavior of micro alloy steel on electric discharge machining is investigated. The influence of machining parameters is examined with an approximate hypothetical model based on temperature distribution. The results indicated a good agreement with experimental observations.

A. Erman TEKKAYA; Eregli Iron

79

Development of a micro-punching machine and study on the influence of vibration machining in micro-EDM  

Microsoft Academic Search

This paper describes the development of a novel micro-punching machine that is capable of producing precision micro-holes. A significant feature of this machine is to fabricate the micro-punch and then the micro-die in the same machine, totally eliminating the eccentricity between the punch and the die when punching is proceeded. By applying vibration machining technique, we can decrease the possibility

Gwo-Lianq Chern; Ying-Jeng Engin Wu; Shun-Feng Liu

2006-01-01

80

MEMS-Based Micro-Electro-Discharge Machining (M EDM) by Electrostatic Actuation of Machining Electrodes on the Workpiece  

Microsoft Academic Search

This paper reports a micro-electro-discharge machining technique that is enabled by electrostatic microactuators. The 18-??m-thick movable copper electrodes that serve as machining tools are microfabricated directly on the surfaces of the workpiece and operated in dielectric machining fluid. A dc voltage of 80-140 V applied between the electrode and the workpiece through a resistance-capacitance pulse generation circuit is leveraged to

Chakravarty Reddy Alla Chaitanya; Ningyuan Wang; Kenichi Takahata

2010-01-01

81

Accuracy improvement in nanographite powder-suspended dielectric fluid for micro-electrical discharge machining processes  

Microsoft Academic Search

Micro-electric discharge machining (?-EDM) is an important manufacturing process that is able to produce components and tools\\u000a with micro-features. Improvement to this process has resulted in the use of powder mixed dielectric (PMD), which results in\\u000a better surface quality and faster machining time. However, the presence of conductive powder in the dielectric fluid negatively\\u000a affects the accuracy of the machining

Gunawan Setia Prihandana; Muslim Mahardika; M. Hamdi; Y. S. Wong; Kimiyuki Mitsui

2011-01-01

82

Electro discharge machining of nickel–titanium 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

83

Performance of cutting tools in machining Cu\\/W alloys for application in EDM electrodes  

Microsoft Academic Search

The aim of this preliminary investigation is to study the performance of three distinct cutting tools, cemented carbide (WC), chemical vapour deposition diamond (CVDD) and polycrystalline diamond (PCD) when dry machining a copper–tungsten alloy. Cutting and feed forces, maximum cutting temperature, surface roughness and tool wear will be studied in function of the cutting time and each cutting tool.It can

J. P. Davim; C. Maranhão; G. Cabral; J. Grácio

2009-01-01

84

3D surface topography assessment of the effect of different electrolytes during electrochemical polishing of EDM surfaces  

Microsoft Academic Search

In many countries the most common polishing practice in die making is to hand polish the part as a finishing operation after the electro discharge machining process (EDM). The usual polishing abrasives are silicon carbide paper and diamond paste of different grit sizes.However, during the last decade researchers especially in Japan and the USA have tried to combine EDM and

H. Ramasawmy; L. Blunt

2002-01-01

85

Investigation of the effects of electrode orientation and fluid flow rate in near-dry EDM milling  

Microsoft Academic Search

This research investigates the effects of electrode lead and tilt angles and dielectric fluid flow rate on material removal rate, tool electrode wear ratio, and surface roughness in near-dry electrical discharge machining (EDM) milling process. Computational fluid dynamics (CFD) model is developed to predict the dielectric fluid flow rate and qualitatively compare with the experimentally measured EDM material removal rate.

Masahiro Fujiki; Jun Ni; Albert J. Shih

2009-01-01

86

Sharpened of saw blades by electrical discharge machining  

Microsoft Academic Search

Electrical discharge machines have undergone rapid improvements in capability, economical operation, speed and flexibility. In fact, electrical discharge machining (EDM) is now the fourth most popular machining process, selling more than all other processes except milling, turning and grinding. Ninety percent of EDM applications in the world are used to produce molds, stamping dies, extrusion dies, forging dies, tool fixtures

Jesús Doval-Gandoy; Ramón Pasandín; Bernardo Fernández

2005-01-01

87

Multiple lead-electrical discharge machining  

NASA Astrophysics Data System (ADS)

Multiple lead-electrical discharge machining (ML-EDM) was investigated to develop the capability and demonstrate the feasibility of applying state-of-the-art electrical discharge machining (EDM) to the manufacturing of mechanical hardware. Two parts selected for the machining tests were a titanium component container and a stainless steel valve mounting plate. Numerous combinations of ML-EDM and conventional EDM tests were conducted on each part, and the results were evaluated for comparison. In all test cases, the cutting time savings of ML-EDM surpassed the conventional EDM by as much as 42%, and when compared to numerical control (NC) milling, a 75% reduction was achieved. A dimensional analysis revealed that the ML-EDM and conventional EDM were similar, but when compared to the NC milled parts, the ML-EDM parts were superior. When the surface finish comparisons were evaluated, the ML-EDM part surfaces were considerably better at higher material removal rates than those of the conventional EDM process. The investigation also revealed an important fact concerning the number of parts to be machined in a single setup.

Brockhoff, R. W.

1985-08-01

88

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

89

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

Microsoft Academic Search

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 µm diameter wire electrode.

Mark Broomfield; Toshihiko Mori; Teruaki Mikuriya; Kazushi Tachibana

2009-01-01

90

MICRO-HOLE PUNCHING USING MULTIPOINT PUNCH AND DIE MADE BY EDM  

Microsoft Academic Search

In this paper a multi-point micro punch and die were developed using tungsten and tool-steel as the punch material. The process of electric discharge machining (EDM) was used to produce both the punch and die. The punches were machined from 5 mm diameter tungsten and 10 mm tool- steel rods by wire electric discharge machining (WEDM) and the die holes

B. Mark

2009-01-01

91

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

92

Model of workpiece erosion for electrical discharge machining process  

NASA Astrophysics Data System (ADS)

The previously published step-wise model (SWM) of cold electrodes erosion of electric arc heaters (EAHs) was modified for the calculation of workpiece removal rate (WRR) in electrical discharge machining (EDM) process. Modified model applies both relations the step-wise erosion model and the point heat source erosion model and takes into account the discharge current, the discharge pulse/pause time and thermophysical properties of machined material. The results of calculations show a reasonable agreement with data obtained experimentally by different authors about different materials and conditions.

Sharakhovsky, Leonid I.; Marotta, Aruy; Essiptchouk, Alexei M.

2006-11-01

93

EDM-Lathe for Micromachining  

Microsoft Academic Search

In this paper a new type of micro-EDM machine is proposed. The machine operates similarly to a turning lathe. An electrode fabrication system is installed which makes it possible to fabricate on-the-machine complex microelectrodes with sharp edges and corners. A prototype set of equipment was realized and test machining proved that a machine of this type can produce microcylindrical, overhung

T. Masuzawa; K. Okajima; T. Taguchi; M. Fujino

2002-01-01

94

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

95

Multiple lead-electrical discharge machining. Final report  

SciTech Connect

Multiple lead-electrical discharge machining (ML-EDM) was investigated to develop the capability and demonstrate the feasibility of applying state-of-the-art electrical discharge machining (EDM) to the manufacturing of mechanical hardware. Two parts selected for the machining tests were a titanium component container and a stainless steel valve mounting plate. Numerous combinations of ML-EDM and conventional EDM tests were conducted on each part, and the results were evaluated for comparison. In all test cases, the cutting time savings of ML-EDM surpassed the conventional EDM by as much as 42%, and when compared to numerical control (NC) milling, a 75% reduction was achieved. A dimensional analysis revealed that the ML-EDM and conventional EDM were similar, but when compared to the NC milled parts, the ML-EDM parts were superior. When the surface finish comparisons were evaluated, the ML-EDM part surfaces were considerably better at higher material removal rates than those of the conventional EDM process. The investigation also revealed an important fact concerning the number of parts to be machined in a single setup. Because of the flushing restrictions of each part, an optimum number of parts to be machined per setup exist. The optimum number varies with each part, and increases above this number actually hinder the operation and become unproductive.

Brockhoff, R.W.

1985-08-01

96

Estimation of tool wear compensation during micro-electro-discharge machining of silicon using process simulation  

NASA Astrophysics Data System (ADS)

A micro-electro-discharge machine (Micro EDM) was developed incorporating a piezoactuated direct drive tool feed mechanism for micromachining of Silicon using a copper tool. Tool and workpiece materials are removed during Micro EDM process which demand for a tool wear compensation technique to reach the specified depth of machining on the workpiece. An in-situ axial tool wear and machining depth measurement system is developed to investigate axial wear ratio variations with machining depth. Stepwise micromachining experiments on silicon wafer were performed to investigate the variations in the silicon removal and tool wear depths with increase in tool feed. Based on these experimental data, a tool wear compensation method is proposed to reach the desired depth of micromachining on silicon using copper tool. Micromachining experiments are performed with the proposed tool wear compensation method and a maximum workpiece machining depth variation of 6% was observed.

Muralidhara, .; Vasa, Nilesh J.; Singaperumal, M.

2010-02-01

97

Investigation of electro-discharge micro-machining of titanium super alloy  

Microsoft Academic Search

Being a difficult-to-cut material, titanium alloy suffers poor machinability for most cutting processes, especially the drilling\\u000a of micro-holes using traditional machining methods. Although electrical discharge machining (EDM) is suitable for machining\\u000a titanium alloys, selection of machining parameters for higher machining rate and accuracy is a challenging task in machining\\u000a micro-holes. The present research attempts to optimize micro-EDM process parameters for

B. B. Pradhan; M. Masanta; B. R. Sarkar; B. Bhattacharyya

2009-01-01

98

Experimental Characterization of Sinking Electrical Discharge Machining Using Water in Oil Emulsion as Dielectric  

Microsoft Academic Search

Electrical discharge machining (EDM) was wildly used in the modern manufacture industry due to its advantage over the traditional manufacture method of some hard to cut materials. However, compared with the traditional manufacture method, the EDM process was inefficiency and environmentally hazardous due to the decomposition of the dielectrics, especially in the case of sinking EDM which used oil based

Yonghong Liu; Yanzhen Zhang; Renjie Ji; Baoping Cai; Fei Wang; Xiaojie Tian; Xin Dong

2012-01-01

99

Near dry electrical discharge machining  

Microsoft Academic Search

This study investigates the near dry electrical discharge machining (EDM) process. Near dry EDM uses liquid–gas mixture as the two phase dielectric fluid and has the benefit to tailor the concentration of liquid and properties of dielectric medium to meet desired performance targets. A dispenser for minimum quantity lubrication (MQL) is utilized to supply a minute amount of liquid droplets

C. C. Kao; Jia Tao; Albert J. Shih

2007-01-01

100

Research Developments in Additives Mixed Electrical Discharge Machining (AEDM): A State of Art Review  

Microsoft Academic Search

Electrical discharge machining (EDM) is a well-established modern machining process used to manufacture geometrically complex shapes, process hard materials that are extremely difficult to machine by conventional machining processes. This noncontact machining technique is continuously emerging from a mere tool and dies making process to a microscale machining applications. In recent years, researches have emphasized on increasing machining performance coupled

Anil Kumar; Sachin Maheshwari; Chitra Sharma; Naveen Beri

2010-01-01

101

LASER ENHANCED ELECTROCHEMICAL MACHINING PROCESS  

Microsoft Academic Search

An experimental apparatus was designed and built for the hybrid process of laser enhanced electrochemical machining (ECM). Comparison experiments had been done between solely ECM and laser enhanced ECM. The machining performance of hybrid process was investigated and compared with solely ECM. The principle of the hybrid process was exposed by analyzing the microstructure of machining surface. The results show

Yaxin Tang

2002-01-01

102

Optimization of anodic oxidation and Cu–Cr oxide catalyst preparation on structured aluminum plates processed by electro discharge machining  

Microsoft Academic Search

This paper describes the optimization of three processes applied in fabrication of a microstructured reactor for complete oxidation of volatile organic compounds. The first process involves the optimization of the electro discharge machining (EDM) method to produce a set of microchannels with a high length to diameter ratio of 100, with a standard deviation from the average diameter below 0.2%,

I. Z. Ismagilov; R. P. Ekatpure; L. T. Tsykoza; E. V. Matus; E. V. Rebrov; M. A. Kerzhentsev; J. C. Schouten

2005-01-01

103

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

104

Influence of electrical conditions on performance of electrical discharge machining with powder suspended in working oil for titanium carbide deposition process  

Microsoft Academic Search

This paper describes the influence of the discharge current and the pulse duration on the titanium carbide (TiC) deposition\\u000a process by electrical discharge machining (EDM) with titanium (Ti) powder suspended in working oil. Although the influence\\u000a of the electrical conditions for removal EDM has been investigated, the criteria for deposition have not been discussed. In\\u000a the experiments, a 1-mm copper

Katsushi Furutani; Hiromichi Sato; Masayuki Suzuki

2009-01-01

105

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

106

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

107

A study of die helical thread cavity surface finish made by Cu-W electrodes with planetary EDM  

Microsoft Academic Search

An experimental research study intended for the application of a planetary electrical discharge machining (EDM) process with\\u000a copper-tungsten (Cu-W) electrodes in the surface micro-finishing of die helical thread cavities made with AISI H13 tool steel\\u000a full-hardened at 53 HRC is presented. To establish the EDM parameters’ effect on various surface finishing aspects and metallurgical\\u000a transformations, three tool electrode Cu-W compositions

José Carvalho Ferreira

2007-01-01

108

Study of an ultrafine w-EDM technique  

Microsoft Academic Search

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 µm diameter) is designed and employed for the study of ultrafine w-EDM. The tension of the wire electrode is

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

2009-01-01

109

The electro-discharge machining surfaces of high-chromium white irons  

Microsoft Academic Search

Electro-discharge machining (EDM) is widely used with hard and brittle materials, which are difficult to machine using conventional techniques. In the EDM process, spark discharges between the electrically conductive workpiece and a tool electrode increase the temperature so that localized melting occurs. Approximately 15% of this molten metal is removed by flushing, while the remainder resolidifies on the workpiece surface

C. P. Tabrett

1996-01-01

110

Electrothermal modelling of anode and cathode in micro-EDM  

Microsoft Academic Search

Micro-electrical discharge machining is an evolution of conventional EDM used for fabricating three-dimensional complex micro-components and microstructure with high precision capabilities. However, due to the stochastic nature of the process, it has not been fully understood. This paper proposes an analytical model based on electro-thermal theory to estimate the geometrical dimensions of micro-crater. The model incorporates voltage, current and pulse-on-time

S H Yeo; W Kurnia; P C Tan

2007-01-01

111

Effect of silicon particles on the rapidly resolidified layer of Al-Si alloys in the electro discharge machining process  

Microsoft Academic Search

The rapidly resolidified layer is formed by the re-solidification of residual molten materials on the machined surface during\\u000a the electric discharge machining (EDM) process. This study adopts a range of 4–29 wt% to change the silicon content in Al-Si\\u000a alloy specimens to clarify the effect of silicon particles including the content, area fraction and intercept length of primary\\u000a silicon particles on

Ko-Ta Chiang; De-Chang Tsai

2008-01-01

112

Electrical discharge machining of TiNiCr and TiNiZr ternary shape memory alloys  

Microsoft Academic Search

This study investigates the influence of the machining characteristics on TiNiX ternary shape memory alloys (SMAs) using electro-discharge machining (EDM). Experimental results show that the material removal rates (MRRs) of Ti50Ni49.5Cr0.5 and Ti35.5Ni49.5Zr15 alloys in the EDM process exhibit a reverse relationship to the product of the alloy's melting temperature and thermal conductivity. The surface roughness (Ra) of the EDMed

S. L. Chen; S. F. Hsieh; H. C. Lin; M. H. Lin; J. S. Huang

2007-01-01

113

Electrical measurements in µ-EDM  

NASA Astrophysics Data System (ADS)

The phenomena occurring between the electrodes in electric discharge machining when manufacturing features on the micro-metre scale (µ-EDM) is not fully understood. Poor quantitative knowledge of the sources of variability affecting this process hinders the identification of its natural tolerance limits. Moreover, improvements in measuring systems contribute to the acquisition of new information that often conflicts with existent theoretical models of this process. The prime objective of this paper is to advance the experimental knowledge of µ-EDM by providing a measurement framework for the electrical discharges. The effects of the electrodes metallic materials (Ag, Ni, Ti, W) on the electrical measurements defined in the proposed framework are analysed. Linear mixed-effects models are fitted to the experimental data using the restricted maximum likelihood method (REML). The main conclusion drawn is that the discharge current and voltage as defined and measured in this framework do significantly depend on the electrode material even when keeping all the other machining conditions unchanged. This investigation was carried out while the authors were at the Manufacturing Engineering Centre of Cardiff University.

Ferri, Carlo; Ivanov, Atanas; Petrelli, Antoine

2008-08-01

114

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

115

Influence of EDM pulse energy on the surface integrity of martensitic steels  

Microsoft Academic Search

Electro-discharge machining (EDM) is essentially a thermal process with a complex metal-removal mechanism, involving the formation of a plasma channel between the tool and workpiece electrodes, resulting in metallurgical transformations, residual tensile stresses and cracking. These properties determine the operational behaviour of the material and can be included in one term: surface integrity. Results of different experimental analysis to characterise

J. C Rebelo; A Morao Dias; D Kremer; J. L Lebrun

1998-01-01

116

Fabrication of high-density micro holes by upward batch micro EDM  

Microsoft Academic Search

A large number of micro holes are needed for biomedical parts, ink-jet nozzles and micro droplet spraying parts. In this study, an inexpensive machining approach for producing a batch of micro holes is proposed. A set of previously introduced w-EDM mechanisms is employed to horizontally cut the batch micro electrodes precisely. Through the process arrangement, the micro electrodes and workpiece

Shun-Tong Chen

2008-01-01

117

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

118

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

119

MicroHardness and Machined Surface Damage Study for Continuous and Discontinuous Ultrasonic Vibration Assisted Electrical Discharge Machining  

Microsoft Academic Search

A versatile process of Electrical Discharge Machining (EDM) using continuous and discontinuous vibrations to workpiece has been developed. The effects of continuous and discontinuous vibration assisted EDM were explored using high Carbon high Chromium steel as work piece and Copper as tool electrode. In this work L18 orthogonal array based on Taguchi design is used to conduct a series of

Jujhar Singh; P. S. Satsangi; R. S. Walia; V. P. Singh

2011-01-01

120

Electrical Discharge Machining of Functionally Graded 15–35 Vol% SiCp\\/Al Composites  

Microsoft Academic Search

A functionally Graded 15–35 volume% silicon carbide particulate (SiCp) reinforced Al359 metal matrix composite (SiCp\\/Al MMC) was drilled by electrical discharge machining (EDM) to assess the machinability and workpiece quality. The machining conditions were identified for both the machining performance and workpiece quality of the EDM process, including some aspects of material removal mechanisms, material removal rate (MRR), electrode tool

Y. W. Seo; D. Kim; M. Ramulu

2006-01-01

121

Microelectro discharge machining as a technology in micromachining  

NASA Astrophysics Data System (ADS)

In recent years, machine facilities for Electro Discharge Machining (EDM) have been dramatically improved. Enormous progress has been obtained with respect to form accuracy and structure precision even in the submicron domain, which qualifies EDM as a technology for microfabrication ((mu) EDM). (Mu) EDM therefore extends the family of existing microtechniques e.g. the LIGA process or silicon surface micromachining. The EDM-technology offers 3D microfabrication of conductive materials independent of their mechanical properties like hardness, brittleness, etc. This capability offers new fields of application for the microfabrication of components made e.g. from stainless steel or titanium. In order to demonstrate the successful application of various (mu) EDM processes components and devices like micro gearwheels, microreactors, micro punching tools and mould inserts for micro injection molding of an optical fiber connector are presented, which have been fabricated by EDM in close cooperation between the Institute of Microtechnology Mainz GmbH and the Swiss EDM-manufacturer AGIE Losone. Based on their know-how the partners aim to optimize (mu) EDM for microfabrication purposes.

Ehrfeld, Wolfgang; Lehr, Heinz; Michel, Frank; Wolf, Andrej; Gruber, Hans-Peter; Bertholds, Axel

1996-09-01

122

Surface Modification of EDMed Surface with Powder Mixed Fluid  

Microsoft Academic Search

The EDMed surface with metal powder mixed fluid has smaller surface roughness and higher resistance to corrosion because of the diffusion of electrode and\\/or powder materials into the machined surface. In this study, a new surface modification technique is proposed to obtain high surface wear resistance using EDM with powder mixed fluid. Firstly, a coating application of nickel layer on

Y. Uno; A. Okada; S. Cetin

123

EDM performance of Cr\\/Cu-based composite electrodes  

Microsoft Academic Search

Electrode materials for electrical discharge machining (EDM) are usually graphite, copper and copper alloys because these materials have high melting temperature, and excellent electrical and thermal conductivity. The electrodes made by using powder metallurgy technology from special powders have been used to modify EDM surfaces in recent years, to improve wear and corrosion resistance. However, electrodes are normally fabricated at

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

2003-01-01

124

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

125

Machine Process Capability Information Through Six Sigma.  

National Technical Information Service (NTIS)

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 featur...

M. F. Lackner

1998-01-01

126

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

127

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

128

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

129

Optimization by Grey relational analysis of EDM parameters on machining Al–10%SiC P composites  

Microsoft Academic Search

Optimization of process parameters is the key step in the Taguchi methods to achieve high quality without cost inflation. Optimization of multiple response characteristics is more complex compared to optimization of single performance characteristics. The multi-response optimization of the process parameters viz., metal removal rate (MRR), tool wear rate (TWR), taper (T), radial overcut (ROC), and surface roughness (SR) on

P. Narender Singh; K. Raghukandan; B. C. Pai

2004-01-01

130

Analysis of Machining Characteristics in Additive Mixed Electric Discharge Machining of Nickel Based Super Alloy Inconel 718  

Microsoft Academic Search

Additive mixed electric discharge machining (AEDM) is a novel innovation for enhancing the capabilities of electrical discharge machining process. The objective of present research work is to study the influence of operating process input parameters on machining characteristics of nickel based super alloy (Inconel 718) in aluminium additive mixed EDM of with copper electrode. The effectiveness of AEDM process on

Anil Kumar; Sachin Maheshwari; Chitra Sharma; Naveen Beri

2011-01-01

131

Cutting austempered ductile iron using an EDM sinker  

Microsoft Academic Search

The cutting of austempered ductile iron (ADI) was investigated in this study. Electro-discharge sinker machining (EDM) was employed to machine ADI materials by using a copper electrode, which was shaped into a different geometrical form. Machinability was evaluated in terms of the metal removal rate, electrode wear rate and surface finish within the machining conditions explored. A suitable pitch electrode

Che Chung Wang; Biing Hwa Yan; Han Ming Chow; Yasuo Suzuki

1999-01-01

132

Designing Steps and Simulation Results of a Pulse Classification System for the Electro Chemical Discharge Machining (ECDM) Process - An Artificial Neural Network Approach  

Microsoft Academic Search

This paper presents the designing steps and simulation results of a pulse classification system for the ECDM process using\\u000a artificial neural networks (ANN). An Electro Discharge Machining (EDM) machine was modified by incorporating an electrolyte\\u000a system and by modifying the control system. Gap voltage and working current waveforms were obtained. By observing the waveforms,\\u000a pulses were classified into five groups.

T. K. K. R. Mediliyegedara; A. K. M. De Silva; D. K. Harrison; J. A. Mcgeough; D. Hepburn

2004-01-01

133

An Experimental Study on Electrical Discharge Machining of Manganese–Zinc Ferrite Magnetic Material  

Microsoft Academic Search

The objective of this research is to investigate the machining characteristics of manganese–zinc (Mn–Zn) ferrite magnetic material using electrical-discharge machining (EDM). The material removal rate, the surface topography, the surface roughness, the recast layer, and the chemical composition of the machined surface were studied in terms of EDM processing variables. Experimental results indicate that the morphology of debris revealed the

Y. H. Guu; Kuan-Lin Tsai; Lin-Ke Chen

2007-01-01

134

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 µm 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 µm to 67 µm square micro-holes on 50 µm thick aluminum, 30 µm thick copper and 20 µm 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

135

A novel technique for the fabrication of herringbone grooves in a dynamic thrust bearing combining UV-LIGA with electro-discharge machining  

Microsoft Academic Search

This paper presents a novel technique for the fabrication of herringbone grooves in a dynamic thrust bearing by combining both UV-LIGA (the German words for lithography, electroplating, and molding) and electro-discharge machining (EDM) processes. A negative photoresist is used to fabricate an electroforming mold from which a microelectrode for the EDM process is electroformed. The last step is to employ

J. S. Kuo; K. T. Chiu; S. W. Hsu; P. H. Chen; Y. S. Liao

2006-01-01

136

Study on vibration-EDM and mass punching of micro-holes  

Microsoft Academic Search

In this research vibration-EDM is realized by the vibrating worktable designed, which is employed in the micro-punching machine we had already developed. It is found that larger feed and better surface finish can be achieved in micro-EDM with vibration machining. Circular and noncircular micro-electrodes of diameter below 200?m were fabricated with vibration-EDM and the setup of u-axis. Experiments to punch

Gwo-Lianq Chern; Yin Chuang

2006-01-01

137

Effect of Deep Cryogenic Treatment on Machinability of Titanium Alloy (Ti6246) in Electric Discharge Drilling  

Microsoft Academic Search

Currently there is a vital need for cost effective machining processes for titanium alloys. Electrical discharge machining (EDM) is used quite extensively in machining titanium alloys due to its favorable features and advantages. This paper investigates the effect of deep cryogenic treatment (DCT) on machinability of Ti 6246 alloy in electric discharge drilling (EDD) by conducting experimental investigations on the

Simranpreet Singh Gill; Jagdev Singh

2010-01-01

138

Manufacturing linear and circular contours using CNC EDM and frame type tools  

Microsoft Academic Search

In traditional electro discharge machining (EDM) the usual practice is to form a 3D female cavity in the work piece by making a corresponding male shaped tool and plunging this into the work piece. Recently, however, computer numerical control (CNC) EDM machines have become available which have the potential to generate a detailed shape without using complex electrodes. This paper

M. Bayramoglu; A. W. Duffill

1995-01-01

139

Gap control for near-dry EDM milling with lead angle  

Microsoft Academic Search

A new gap control strategy for five-axis milling using near-dry electrical discharge machining (EDM) has been experimentally investigated. The conventional EDM control strategy only allows the retraction of the electrode in the direction of machining trajectory, which results in inefficient gap control when the electrode is not perpendicular to the workpiece. The new gap controller is capable of retracting the

Masahiro Fujiki; Gap-Yong Kim; Jun Ni; Albert J. Shih

2011-01-01

140

A Study of Tool Electrode Materials and Flushing Techniques in micro EDM  

Microsoft Academic Search

The feasibility of using foil materials as tool electrode in micro electro discharge machining (micro EDM) has provided new machining alternative for the spark erosion of micro grooves. To complement the widely used (and expensive) micro EDM tool electrode material (tungsten), two cost effective materials namely graphite and stainless steel have been tried as tool electrodes. Recent technological innovations have

Murali Meenakshi Sundaram; Yeo Swee Hock; Kamlakar P. Rajurkar

141

Machine scheduling with resource dependent processing times  

Microsoft Academic Search

We consider several parallel machine scheduling settings with the objective to min- imize the schedule makespan. The most general of these settings is unrelated parallel machine scheduling. We assume that, in addition to its machine dependence, the processing time of any job is dependent on the usage of a scarce renewable resource. A given amount of that resource, e.g. workers,

Alexander Grigoriev; Maxim Sviridenko; Marc Uetz

2007-01-01

142

A new tool wear compensation method based on real-time estimation of material removal volume in micro-EDM  

Microsoft Academic Search

Owing to the reduced tool area and poor flushing conditions in deep holes, tool wear in micro-electrical discharge machining (EDM) is more significant than in macro-EDM. In micro-EDM drilling, the z-axis of the tool position is monitored as machining progresses. However, due to significant electrode wear, the machined hole depth is not identical to the programmed depth of the hole,

E. Aligiri; S. H. Yeo; P. C. Tan

2010-01-01

143

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

144

Discussion of electrical discharge machining in gas  

Microsoft Academic Search

Summary form only given. For the microcosmical understanding of electrical discharge machining (EDM) in gas (dry EDM), the influences of such parameters as polarity and gas pressure on EDM in gas were discussed based on theory of gas discharge and experiments; meanwhile, the influencing factors of material remove rate (MRR) in dry EDM and reasons for the low relative wear

L. Q. Li; W. S. Zhao; Z. L. Wang; B. Q. Kou; L. Y. Li

2004-01-01

145

Electrical discharge machining of a NiAlFe ternary shape memory alloy  

Microsoft Academic Search

The electro-discharge machining (EDM) characteristics of a NiAlFe ternary shape memory alloy (SMA) have been investigated in this study. Experimental results reveal that the material removal rates (MRRs) of Ni60Al24.5Fe15.5 and Ti35.5Ni49.5Zr15 alloys in the EDM process exhibit a reverse relationship to the product of the alloy's melting temperature and thermal conductivity. In addition, a precise EDM machining of NiAlFe

S. L. Chen; S. F. Hsieh; H. C. Lin; M. H. Lin; J. S. Huang

2008-01-01

146

Novel power supply topology for large working gap dry EDM  

Microsoft Academic Search

For material removal in rotor balancing machines, dry Electrical Discharge Machining (EDM) with large working gap is an advantageous alternative to the common mechanical drilling, grinding or laser drilling. This paper presents a novel topology of a power supply required for such an application. It has an increased ignition voltage capability of up to 10 kV compared to standard power

A. Looser; L. Linares; C. Zwyssig; J. W. Kolar

2010-01-01

147

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

148

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

149

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 µm 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 µm was realized successfully.

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

2009-11-01

150

Effect of ultrasonic-assisted EDM on the surface integrity of cemented tungsten carbide (WC-Co)  

Microsoft Academic Search

This paper studies the effects of tool electrode ultrasonic vibration on some surface integrity properties of cemented tungsten\\u000a carbide (WC-10%Co) in the electrical discharge machining (EDM) process. Surface integrity concerns surface alterations associated\\u000a with a manufacturing process, including surface topography, surface metallurgy, and changes of the mechanical and physical\\u000a properties of the material as well as residual stresses. Scanning electron

Amir Abdullah; Mohammad R. Shabgard; A. Ivanov; Mohammad T. Shervanyi-Tabar

2009-01-01

151

Multiple lead-electrical discharge machining  

Microsoft Academic Search

Multiple lead-electrical discharge machining (ML-EDM) was investigated to develop the capability and demonstrate the feasibility of applying state-of-the-art electrical discharge machining (EDM) to the manufacturing of mechanical hardware. Two parts selected for the machining tests were a titanium component container and a stainless steel valve mounting plate. Numerous combinations of ML-EDM and conventional EDM tests were conducted on each part,

R. W. Brockhoff

1985-01-01

152

Overview on Pyramid Machines for Image Processing.  

National Technical Information Service (NTIS)

This paper is intended to review the existing hierarchical multiprocessor machines dedicated to Image Processing (IP). Some general design concepts are given and compared in terms of hardware and software complexity. 33 refs., 9 figs., 3 tabs. (ERA citati...

V. Di Gesu

1986-01-01

153

Multiple Lead-Electrical Discharge Machining. Final Report.  

National Technical Information Service (NTIS)

Multiple lead-electrical discharge machining (ML-EDM) was investigated to develop the capability and demonstrate the feasibility of applying state-of-the-art electrical discharge machining (EDM) to the manufacturing of mechanical hardware. Two parts selec...

R. W. Brockhoff

1985-01-01

154

Modeling and Experimental Investigations of Dry Electrical Discharge Machining (DEDM)  

NASA Astrophysics Data System (ADS)

Paper presents mathematical modeling and practical application of Dry Electrical Discharge Milling (DEDM) process using compressed air as dielectric. A comparison of this machining method with kerosene--based EDM milling is presented. The reported results refer to the experiments on micro--machining with thick--walled electrodes. The advantages and drawbacks of this machining method, within the field of micro-machining are described and discussed.

Skrabalak, Grzegorz; Kozak, Jerzy

2011-10-01

155

Modeling and Experimental Investigations of Dry Electrical Discharge Machining (DEDM)  

Microsoft Academic Search

Paper presents mathematical modeling and practical application of Dry Electrical Discharge Milling (DEDM) process using compressed air as dielectric. A comparison of this machining method with kerosene--based EDM milling is presented. The reported results refer to the experiments on micro--machining with thick--walled electrodes. The advantages and drawbacks of this machining method, within the field of micro-machining are described and discussed.

Grzegorz Skrabalak; Jerzy Kozak

2011-01-01

156

Multistage machining processes variation propagation analysis based on machining processes weighted network performance  

Microsoft Academic Search

To quantitatively analyze variation propagation in multistage machining processes, a method of variation propagation analysis\\u000a and variation source identification based on manufacturing cost was proposed in this paper. With the method, a weighted network\\u000a of multistage machining processes based on complex network theory was introduced, and variation propagation stability of multistage\\u000a machining processes was analyzed by virus-spreading model. Furthermore, key

Yongtao Qin; Liping Zhao; Yiyong Yao; Damin Xu

2011-01-01

157

Clarification of EDM Phenomena by Spectroscopic Analysis  

NASA Astrophysics Data System (ADS)

In electrical discharge machining (EDM), workpiece is machined using heat of the arc-plasma generated in the discharge gap after dielectric breakdown. The characteristics and behavior of the arc-plasma during a single discharge have a great influence on the formation of the discharge crater. In order to improve the machining accuracy and surface roughness of the workpiece, it is quite necessary to research on plasma behavior and its characteristics. In this study, light intensities radiated from the plasma which are considered to reflect the material removal behavior were measured using a spectrometer under different machining conditions. It was found that the starting moment when light intensity was detected had a time delay after the dielectric breakdown. It is because of the time needed for the material to be evaporated before its temperature reaches the boiling point. Besides, the time delay increases accordingly by slowing down the rise speed of the discharge current because of lower heat flux flowing into the surface of the workpiece. In addition, heat conduction analysis was conducted to compare the time delay calculated with the experimental ones. It was found that plasma expanded in a rapid speed within about 180ns right after dielectric breakdown and remained constant with the diameter of about 20µm after that under a roughing condition of micro EDM.

Qu, Chao; Natsu, Wataru; Kunieda, Masanori

158

EFFECTS OF WORKPIECE ROTATION ON MACHINABILITY DURING ELECTRICAL-DISCHARGE MACHINING  

Microsoft Academic Search

This work presents a novel rotary (EDM) electrical-discharge machining cutting process for a hard-to-machine cylindrical workpiece. An experimental analysis was carried out on an AISI D2 tool steel with a copper electrode. The effects of machining parameters such as pulsed current, pulse on-time, and workpiece rotation on material removal rate and surface roughness were analyzed. These effects were compared with

Y. H. Guu; H. Hocheng

2001-01-01

159

A Study of Optimization of Machining Parameters for Electrical Discharge Machining of Boron Carbide  

Microsoft Academic Search

The correct selection of manufacturing conditions is one of the most important aspects to take into consideration in the majority of manufacturing processes and, particularly, in processes related to electrical discharge machining (EDM) of conductive ceramic materials. It is these conditions that determine such important characteristics as surface roughness, electrode wear, and material removal rate. In this article, a review

I. Puertas; C. J. Luis

2004-01-01

160

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

161

Gaussian Processes in Machine Learning  

Microsoft Academic Search

We give a basic introduction to Gaussian Process regression models. We focus on understanding the role of the stochastic process and how it is used to define a distribution over functions. We present the simple equations for incorporating training data and examine how to learn the hyperparameters using the marginal likelihood. We explain the practical advantages of Gaussian Process and

Carl Edward Rasmussen; Max Planck

2003-01-01

162

Metallurgical effects from conventional, EDM, and electrochemical drilling  

Microsoft Academic Search

Poor surface integrity of a small deep hole can serve as an initiation point for failure. The drilling methods evaluated in this study were peck drilling, shaped tube electrolytic machining (STEM drilling) and electric discharge (EDM) drilling. All three methods are susceptible to poor surface quality if done incorrectly. Scanning electron microscopy, metallography, and hardness traverses were used to characterize

Fuller

1980-01-01

163

Electrical discharge machining of titanium alloy (Ti–6Al–4V)  

Microsoft Academic Search

In this study, the electrical discharge machining (EDM) of titanium alloy (Ti–6Al–4V) with different electrode materials namely, graphite, electrolytic copper and aluminium and process parameters such as, pulse current and pulse duration were performed to explore the influence of EDM parameters on various aspects of the surface integrity of Ti6Al4V. Scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectrograph

Ahmet Hasçalik; Ula? Çayda?

2007-01-01

164

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

Microsoft Academic Search

Abstract 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 modification method by EDM with powder suspended

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

165

Fabrication of high-aspect-ratio microscale mold inserts by parallel ?EDM  

Microsoft Academic Search

The micro-electrical-discharge-machining (?EDM) technique is an alternative to LiGA (Lithographie, Galvanoformung, Abformung) for fabricating metal-based high-aspect-ratio microscale structures (HARMS). Traditional ?EDM is a serial subtractive machining technique in which cuts are performed sequentially, and is therefore difficult to use for generating complex micropatterns on surfaces. In this paper, we report results of a hybrid microfabrication approach, combining micropattern definition with

D. M. Cao; J. Jiang; R. Yang; W. J. Meng

2006-01-01

166

Fabrication of high-density micro holes by upward batch micro EDM  

NASA Astrophysics Data System (ADS)

A large number of micro holes are needed for biomedical parts, ink-jet nozzles and micro droplet spraying parts. In this study, an inexpensive machining approach for producing a batch of micro holes is proposed. A set of previously introduced w-EDM mechanisms is employed to horizontally cut the batch micro electrodes precisely. Through the process arrangement, the micro electrodes and workpiece are not unloaded, repositioned and re-corrected until all the tasks are completed. The micro workpiece is clamped onto the specially designed jig and moved above the micro electrodes to perform machining of the mass micro holes by upward batch micro EDM. The entire procedure is carried out on a developed multifunctional tabletop CNC machine tool. An array of 400 through holes of the identical sizes is successfully fabricated on a stainless-steel plate with a thickness of 30 µm by using the modified peck-drilling method. Experimental results confirmed that the proposed approach could accelerate the removal of debris, reduce the occurrence of abnormal discharges and decrease the machining time.

Chen, Shun-Tong

2008-08-01

167

Asynchronous Finite State Machines. Simulations with Imposed Processing Constraints.  

National Technical Information Service (NTIS)

The action of computer control systems on continuous time discrete state processes can be accurately represented by asynchronous finite state machines, and, in particular, a subclass of these machines termed simple asynchronous machines, or SAMs. To under...

S. Y. Kwonkam M. E. Koliski A. T. Miller T. L. Johnson

1986-01-01

168

Electric discharge machining of Al–10%SiC P as-cast metal matrix composites  

Microsoft Academic Search

The use of unconventional machining techniques in shaping aluminium metal matrix composites (Al-MMC) has generated considerable interest as the manufacturing of complicated die contours in these hard materials to a high degree of accuracy and surface finish is difficult. Electrical discharge machining (EDM) is an important process for machining difficult-to-machine materials like metal matrix composites. Among the many unconventional processing

P. Narender Singh; K. Raghukandan; M. Rathinasabapathi; B. C. Pai

2004-01-01

169

White Layer Composition, Heat Treatment, and Crack Formation in Electric Discharge Machining Process  

Microsoft Academic Search

Characteristics of electric discharge machined (EDM) surfaces of normalized, quenched, and quenched and tempered-treated steels\\u000a in kerosene and deionized-water dielectric liquids are investigated. Optical microscopy, scanning electron microscopy (SEM)\\u000a and X-ray diffractometry are employed to analyze the machined surface. Surface cracks are examined in terms of white layer\\u000a composition, heat treatment of the workpiece material, and operational parameters used, such

Bülent Ekmekci

2009-01-01

170

Multiple lead-electrical discharge machining. Final report  

Microsoft Academic Search

Multiple lead-electrical discharge machining (ML-EDM) was investigated to develop the capability and demonstrate the feasibility of applying state-of-the-art electrical discharge machining (EDM) to the manufacturing of mechanical hardware. Two parts selected for the machining tests were a titanium component container and a stainless steel valve mounting plate. Numerous combinations of ML-EDM and conventional EDM tests were conducted on each part,

Brockhoff

1985-01-01

171

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-µm 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

2011-09-06

172

Digital Signal Processing and Machine Learning  

NASA Astrophysics Data System (ADS)

Any brain-computer interface (BCI) system must translate signals from the users brain into messages or commands (see Fig. 1). Many signal processing and machine learning techniques have been developed for this signal translation, and this chapter reviews the most common ones. Although these techniques are often illustrated using electroencephalography (EEG) signals in this chapter, they are also suitable for other brain signals.

Li, Yuanqing; Ang, Kai Keng; Guan, Cuntai

173

Rockburst Prediction Using Gaussian Process Machine Learning  

Microsoft Academic Search

Rockburst is a geological disaster occurred usually in deep mines. Because of poor understanding of the mechanism and influence factors of rockburst, it is very difficult to give accurate prediction using conventional methods. A new model based on Gaussian process (GP), which is a probabilistic kernel machine leaning and has become a power tool for solving highly nonlinear problems, therefore,

Guo-Shao Su; Ke-Shi Zhang; Zhi Chen

2009-01-01

174

Machining piezoelectric (PZT) ceramics using an electrochemical spark machining (ECSM) process  

Microsoft Academic Search

Machining of advanced engineering materials such as composites and ceramics is important but it is very difficult and uneconomical to do so by conventional methods of machining. A need for new techniques for machining these advanced engineering materials cannot be over-emphasized. In this study, the authors have attempted to explore the feasibility of using an electrochemical spark machining (ECSM) process

Y. P. Singh; Vijay K. Jain; Prashant Kumar; D. C. Agrawal

1996-01-01

175

On Electro Discharge Machining of Inconel 718 with Hollow Tool  

Microsoft Academic Search

Inconel 718 is a nickel-based alloy designed for high yield, tensile, and creep-rupture properties. This alloy has been widely\\u000a used in jet engines and high-speed airframe parts in aeronautic application. In this study, electric discharge machining (EDM)\\u000a process was used for machining commercially available Inconel 718. A copper electrode with 99.9% purity having tubular cross\\u000a section was employed to machine

S. Rajesha; A. K. Sharma; Pradeep Kumar

2011-01-01

176

Relationship of Surface Roughness with Current and Voltage During Wire EDM  

Microsoft Academic Search

Wire EDM is in use for a long time for cutting punches and dies, shaped pockets and other machine parts. Surface finish of the machined surface mainly depends on current and voltage used during machining. In the present research experimental investigations have been conducted to establish relationships of job surface finish with current and voltage. Brass wires of diameters 0.3,

Ahsan Ali Khan; Munira Bt. Mohd Ali; Norhashimah Bt. Mohd Shaffiar

2006-01-01

177

Die surface modification technique by EDM with special pulse power supply  

NASA Astrophysics Data System (ADS)

This paper describes a new method of die surface modification by ordinary Electrical Discharge Machining (EDM) tool. First, the principle of this method is studied. Secondly, the reason for appearance of cracks on the surface of coating layer in the electrical discharge coating with conventional pulse power supply are analyzed. At last, the new type special pulse power supply with additional pulse current is designed. Scenix single-chip is selected as pulse generator, which runs the fastest among all single-chips. The corresponding program can make the pulse power supply produce the additional pulse current. At the same time, the special pulse power supply can communicate different machining parameters with industrial personal computer by serial port of PIC single-chip according to the coating requires, and then PIC single-chip convey machining parameters to Scenix single-chip by the communication interface. Through process experiment, the special pulse power supply for electrical discharge coating behaves well, and the compacted coating layer without cracks deposited on the surface of die by EDM can be obtained, which can prolong the life of die.

Li, Xiaohai; Wang, Decheng; Fang, Yu; Yan, Bingbing

2010-12-01

178

In-process measurement problems in machine tool applications  

Microsoft Academic Search

Sensor-based machine tool management systems will provide many, well documented benefits in the use of modern machine tools. A vital element will be the provision of sensing methods able to measure in-process, that is whilst machining is taking place, within machine tool environments. This paper describes the background to, and development of a ‘bottom up’ approach to tackling this sensing

R. I. GROSVENOR; C. KHARPOUTLY; K. F. MARTIN

1991-01-01

179

Improving Electrical Discharge Machined Surfaces Using Magnetic Abrasive Finishing  

Microsoft Academic Search

A recast layer is invariably present on surfaces produced by electrical discharge machining (EDM). For some metals with high hardness, the recast layer may contain micro-cracks. This damaged layer can affect the service life of the parts produced by this method. This investigation demonstrates that magnetic abrasive finishing (MAF) process using unbonded magnetic abrasives (UMA), can improve the quality of

Biing-Hwa Yan; Geeng-Wei Chang; Jung-Hsien Chang; Rong-Tzong Hsu

2004-01-01

180

Implementation of online NURBS curve fitting process on CNC machines  

Microsoft Academic Search

The study aims to develop a method for implementing an online non-uniform rational B-spline (NURBS) curve fitting process\\u000a on CNC machines for improving the quality and efficiency of machining. Conventional CAD\\/CAM\\/CNC systems usually induce some\\u000a machining difficulties and limit the machining results in real applications. Therefore, some researchers have proposed various\\u000a methods for improving the machining results. An online NURBS

Syh-Shiuh Yeh; Hsin-Chuan Su

2009-01-01

181

Effect of technological parameter on the process performance for electric discharge milling of insulating Al 2O 3 ceramic  

Microsoft Academic Search

Engineering ceramics have been widely used in modern industry. However, the manufacture of ceramic blanks is not an efficient process. The shaping of ceramic blanks with conventional machining methods (such as grinding), is a long, labour-intensive and costly process. Wire electric discharge machining (WEDM) is able to effectively slice conducting ceramics. Electrical discharge machining (EDM) and electrical discharge grinding (EDG)

Y. H. Liu; X. P. Li; R. J. Ji; L. L. Yu; H. F. Zhang; Q. Y. Li

2008-01-01

182

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

183

Mining Machine Control Signal Processing System  

SciTech Connect

A signal processing system for an underground mining machine having a steerable mineral cutter and a sensor which senses natural radiation emitted from rock strata overlaying the radiation absorbing mineral and which derives a sensor signal representative of the cutting horizon of the cutter, comprises processing means for receiving and processing the sensor signal to derive an operational signal indicative of the cutter horizon of the cutter, calibration means for accepting a fed in calibration signal representative of a known existing condition of the cutting horizon and comparator means for comparing the derived operational signal with the calibration signal to determine an error in the derived operational signal and for instructing the processing means to apply a suitable correction to the derived operational signal.

Fecitt, G.J.

1984-01-31

184

INVESTIGATION OF ELECTROCHEMICAL PARAMETERS INTO AN ELECTROCHEMICAL MACHINING PROCESS  

Microsoft Academic Search

Electrochemical machining (ECM) is a process where the surface of a part is removed via an anodic charge transfer. Electropolishing, electrochemica l deburring, or radiusing are electrochemical machining processes where the metal removal must be uniform or localized, respectively. ECM is affected by many parameters such as machining gap, electric field modulation, electrolyte properties, and flow rate. This paper focuses

Jenny J. Sun; E. Jennings Taylor; Lawrence E. Gebhart; Chengdong D. Zhou; Jeffrey M. Eagleton; Robert P. Renz

185

An integrated intelligent process planning system (IIPPS) for machining  

Microsoft Academic Search

A key component of computer integrated manufacturing (CIM) is computer aided process planning (CAPP). Process planning in machining involves the determination of the cutting operations and sequences, the selection of machine tools and cutting tools, the calculation of machining parameters, and the generation of CNC part programs. Industrial structures in Norway are defined as small and medium-sized companies. The important

KESHENG WANG

1998-01-01

186

Design of NURBS Curve Fitting Process on CNC Machines  

Microsoft Academic Search

This study aims to design a method for implementing the non-uniform rational B-spline (NURBS) curve fitting process on CNC machines for improving the machining quality and efficiency. The conventional CAD\\/CAM\\/CNC systems usually induce some machining problems and limit the machining results in real applications. An on-line NURBS curve fitting process consists of fetching and fitting stages is developed in this

Syh-Shiuh Yeh; Shin-Chun Su

2007-01-01

187

Rapid tooling aided by reverse engineering to manufacture EDM electrodes  

Microsoft Academic Search

The present work deals with the application of indirect rapid tooling (RT) technology to manufacture electrical discharge\\u000a machining (EDM) copper electrodes from investment casting, with wax prototypes made by ThermoJet 3D printing, a rapid prototyping\\u000a (RP) technique. The reverse engineering (RE) method is utilised to transform the point cloud data of an object surface, obtained\\u000a from 3D digitising, in a

José Carvalho Ferreira; Artur S. Mateus; Nuno F. Alves

2007-01-01

188

Influence of reaction force on the electrode in micro hole drilling by micro EDM  

Microsoft Academic Search

Micro electrical discharge machining (EDM) is widely used to drill micro hole with high aspect ratio in any electrically conductive material regardless its hardness. Due to the electrode wear during machining, the electrode has to be prepared long to compensate the wear length. It is found that the discharge gap of a micro hole by a long and thin electrode

Jianzhong Li; Yusheng Zhang; Zuyuan Yu

2011-01-01

189

Simulation of Surface Integrity for Nanopowder-Mixed Dielectric in Micro Electrical Discharge Machining  

NASA Astrophysics Data System (ADS)

The use of powder-mixed dielectric for electrical discharge machining (PMD-EDM) and micro-electrical discharge machining (PMD micro-EDM) has been shown to reduce machined surface roughness and surface defects, such as, recast layer thickness. However, these were mainly empirical studies which had limited capacity to elucidate the physics and characteristics of the PMD-EDM process. In the current study, a new numerical model has been developed to describe the PMD micro-EDM process. The model has taken into account the larger expansion of the plasma channel and reduction in heat flux distributed to the workpiece because of the presence of powder particles. It has been analyzed using finite element methods (FEMs) and based on the multiple discharge approach. The heat source expansion factor due to the presence of powder particles has been estimated to be 1.07 at 0.02 g/L powder concentration. The fraction of heat flux to the workpiece has been found to decrease from 0.24 at 0.02 g/L to 0.11 at 0.2 g/L powder concentration. For model validation, simulated R max and recast layer thickness values were compared with their corresponding measured values. The simulated and measured results varied with the same general trend which suggested that the proposed process model for PMD micro-EDM was fundamentally sound.

Tan, P. C.; Yeo, S. H.

2013-06-01

190

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, Ozgür; Acar, Asli; Halkaci, Selçuk

2006-08-01

191

The use of active materials for machining processes: A review  

Microsoft Academic Search

This paper provides a review of active materials in the context of applications to manufacturing machining processes. The important concepts and background of active materials are briefly introduced. After which, the applications of these materials are discussed as applied to relevant themes in machining processes. A brief overview of research work on experimental and theoretical studies on various process monitoring

Matthew T. Bement; Daniel A. Hartman; Ronald E. Smith; Charles R. Farrar

2007-01-01

192

DRY WIRE ELECTRICAL DISCHARGE MACHINING OF THIN WORKPIECE  

Microsoft Academic Search

This study investigates the dry wire electrical discharge machining (EDM) on thin workpieces. Dry EDM experiments were conducted in air, which was used as the dielectric fluid. Effects of spark cycle (T), spark on-time (Ton), air flow rate, workpiece thickness, and type of work-material were studied under wet and dry EDM conditions. The material removal rate (MRR) was low in

C. C. Kao; Jia Tao; Sangwon Lee; Albert J. Shih

193

Rapid prototyping of zirconium diboride/copper electrical discharge machining electrodes  

NASA Astrophysics Data System (ADS)

The acceptance of rapid prototyping (RP) as the predominant technique for producing polymer and paper parts directly from computer-aided design (CAD) models has led many corporations and universities to try to extend its capabilities to more robust materials. In addition to producing prototype metal and ceramic parts, a significant effort has been made to create parts that are useful as tools and dies or that reduce the time necessary to create tools and dies. Most materials used for tools and dies are very hard, because they need to be able to withstand millions of cycles before failing. Electrical discharge machining (EDM) is the most common method used to machine tools and dies out of hard materials. A method for producing EDM electrodes using RP could greatly reduce the time and cost involved in creating tools and dies. A new EDM electrode material made up of zirconium diboride and copper (ZrBsb2/Cu) that is superior to traditional EDM electrodes has been investigated. The processing techniques necessary for creating Zrsb2/Cu electrodes from powders of ZrB2 and copper have been developed. These ZrBsb2/Cu electrodes have a better wear ratio and a faster sink rate than graphite, copper or tungsten/copper EDM electrodes. Performance variables that were tracked are: (1) wear ratio, (2) sink rate and (3) surface finish, where ZrBsb2/Cu, copper, graphite and W/Cu were used as anodes (electrodes) and stainless steel as cathodes (workpieces). The ZrBsb2/Cu electrode material system retains its superior EDM electrode performance across a number of materials processing and compositional variations. Scanning electron microscopy (SEM) was used to study the electrodes after EDM. These SEM observations facilitated an understanding of the superior EDM electrode performance characteristics of ZrBsb2/Cu to traditional EDM electrode material systems. A method for creating geometrically-complex ZrBsb2/Cu EDM electrodes using the selective laser sintering (SLS) RP technique was developed. Polymer coated ZrBsb2 powders are processed in a SLS machine to produce the desired geometry. Subsequent polymer burnout, sintering of the ZrBsb2 and copper infiltration are performed in a high-temperature furnace.

Stucker, Brent Eric

194

Micro Hole Processing Using Electro-Chemical Discharge Machining  

NASA Astrophysics Data System (ADS)

Recently, micro holes processing on glass were focused on chemical and biological filed. Authors focused on Electro-Chemical Discharge Machining (ECDM) to machine micro holes on glass, and developed the ECDM device. This paper reports about feedback circuit for machining-stop system and two-step machining which were developed to reduce the smallest diameter of micro hole. Additionally, the tool electrode of which diameter was 20 µm was produced using Electro-Chemical Machining (ECM). As a result, the diameter of micro hole was reached to 12 µm.

Mochimaru, Yasuhiro; Ota, Minoru; Yamaguchi, Keishi

195

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

196

Fabrication of a stainless steel shadow mask using batch mode micro-EDM  

Microsoft Academic Search

A metal shadow mask for organic thin-film transistors (OTFTs) has been fabricated by batch mode electro-discharge machining\\u000a (EDM). Batch mode micro-electro-discharge machining method was applied for productivity improvement. Negative electrode with\\u000a multiple holes (3 × 3 or 4 × 4) was fabricated using a single tool electrode. With the negative electrode, 3 × 3 and 4 × 4\\u000a tool electrode arrays are EDMed; 6 × 6 and 16 × 16 square hole

Sang Min Yi; Min Soo Park; Young Soo Lee; Chong Nam Chu

2008-01-01

197

Simulations of ARMA and ARMAX Models for a Machining Process  

Microsoft Academic Search

The needs of accuracy of machines are strictly increasing for the manufacturing processes. It is costly to use high precision machine to achieve the goal. Therefore, if the forecasting of errors can be obtained from the gathered past error values, it allows the control system to compensate the errors. In this paper, the simulations of ma nufacturing processes are using

W. K. Tang; Y. K. Wong

2000-01-01

198

Unrelated Parallel Machine Scheduling with Resource Dependent Processing Times  

Microsoft Academic Search

We consider unrelated machine scheduling problems with the objective to minimize the schedule makespan. In addition to its machine- dependence, the processing time of any job is also dependent on the usage of a scarce renewable resource. An amount of k units of that resource, e.g. workers, can be distributed over the jobs in process, and the more of that

Alexander Grigoriev; Maxim Sviridenko; Marc Uetz

2005-01-01

199

Some digital signal processing techniques for induction machines diagnosis  

Microsoft Academic Search

? Abstract - This paper investigates the recent advances on digital signal processing techniques for induction machines diagnosis. Since non-invasive sensors offer a relatively simple and cost effective fault diagnosis, more emphasis is given to stator current analysis rather than vibration or acoustic analysis in induction machines. Here, further interest has been paid on modern signal processing techniques with a

Shahin Hedayati Kia; Humberto Henao; Gerard-Andre Capolino

2011-01-01

200

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

201

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

202

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?áková, Lucie; Stráský, Josef; Ba?áková, Markéta; Novotná, Katarína; Jane?ek, Miloš

2011-07-18

203

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

204

Stochastic modeling of EDM with a view to off-line optimization  

NASA Astrophysics Data System (ADS)

The working principle of electrical discharge machining (EDM) is discussed and its importance to the manufacturing industry is emphasized. Current research thrusts are outlined, and the need for the proposed methodology, Data Dependent Systems (DDS), to deal with the random and complex nature of EDM, is cited. A pilot experiment carried out to collect surface profiles for characterization by DDS models is described and the main experiment designed to verify erosion rate and surface roughness formulas is examined. The derivation of expressions for melt depth and radius of a crater are given in terms of machining parameters and material properties. Attempts to identify the distinguishing features of arcing and sparking and their use in developing a strategy for online computer contol of EDM are explored. Possible adaptive control strategies based on these features are proposed.

Pandit, S. M.; Rajurkar, K. P.; Venkatapathy, B.

1984-01-01

205

A Robust Helical Abrasive Flow Machining (HLX-AFM) Process  

NASA Astrophysics Data System (ADS)

Abrasive flow machining (AFM) is a fine finishing process in which an abrasives laden semi-solid paste is used for finishing of internal inaccessible recesses or surfaces. Recently, several modifications in the tooling with/without additional machining action have been tried for increasing the material removal in the AFM. The present study is about a novel development in the AFM process, towards the enhancement of material removal rate while polishing the internal cylindrical surfaces. The modified process is termed as helical abrasive flow machining process (HLX-AFM). Taguchi's quality engineering approach has been applied to the developed HLX-AFM process, leading to the optimization of various process parameters and thus the development of a robust machining process with significantly enhanced material removal.

Brar, B. S.; Walia, R. S.; Singh, V. P.; Sharma, M.

2013-01-01

206

A micromachining process for die-scale pattern transfer in ceramics and its application to bulk piezoelectric actuators  

Microsoft Academic Search

This paper reports on a batch mode planar pattern transfer process for bulk ceramics, glass, and other hard, brittle, nonconductive materials suitable for micromachined transducers and packages. The process is named LEEDUS, as it combines lithography, electroplating, batch mode micro electro-discharge machining (?EDM) and batch mode micro ultrasonic machining (?USM). An electroplating mold is first created on a silicon or

Tao Li; Yogesh B. Gianchandani

2006-01-01

207

Modelling of abrasive flow machining process: a neural network approach  

Microsoft Academic Search

A simple neural network model for abrasive flow machining process has been established. The effects of machining parameters on material removal rate and surface finish have been experimentally analysed. Based on this analysis, model inputs and outputs were chosen and off-line model training using back-propagation algorithm was carried out. Simulation results confirm the feasibility of this approach and show a

R. K. Jain; V. K. Jain; P. K. Kalra

1999-01-01

208

Characterization of machines for processing of waste materials  

Microsoft Academic Search

The paper presents the machines for processing of waste materials in agriculture. There are many waste materials from which it is possible by means of suitable machines to obtain the product which can be favourably used. The aim of crushing of waste materials is to reduce their volume and to use them favourably. For crushing small waste wood and branches

A. Ploj; B. Mursec; F. Cus; U. Zuperl

2006-01-01

209

Die surface modification technique by EDM with special pulse power supply  

Microsoft Academic Search

This paper describes a new method of die surface modification by ordinary Electrical Discharge Machining (EDM) tool. First, the principle of this method is studied. Secondly, the reason for appearance of cracks on the surface of coating layer in the electrical discharge coating with conventional pulse power supply are analyzed. At last, the new type special pulse power supply with

Xiaohai Li; Decheng Wang; Yu Fang; Bingbing Yan

2010-01-01

210

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

Microsoft Academic Search

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

Shun-Tong Chen

2007-01-01

211

A novel approach for batch production of micro holes by micro EDM  

Microsoft Academic Search

The paper proposed a novel approach of effective production of mass micro holes. A set of micro w-EDM mechanism is designed and mounted on the developed tabletop precision machine tool. The tension of micro wire is precisely controlled by magnetic force. In addition, the micro vibrations of the wire during discharging are effectively suppressed by the developed vibration suppression system.

S. T. Chen; Y. S. Liao

212

Material removal rate (MRR) study in the cylindrical wire electrical discharge turning (CWEDT) process  

Microsoft Academic Search

As using wire EDM (WEDM) technology, complicated cuts can made through difficult to machine electrically conductive components, the cylindrical wire electrical discharge turning (CWEDT) process was developed to generate precise cylindrical forms on complicate, hard and difficult to machine materials. A precise, flexible and corrosion resistance submerged rotary spindle was designed and added to a conventional five axis CNC WEDM

M. J. Haddad; A. Fadaei Tehrani

2008-01-01

213

Metallurgical effects from conventional, EDM, and electrochemical drilling  

SciTech Connect

Poor surface integrity of a small deep hole can serve as an initiation point for failure. The drilling methods evaluated in this study were peck drilling, shaped tube electrolytic machining (STEM drilling) and electric discharge (EDM) drilling. All three methods are susceptible to poor surface quality if done incorrectly. Scanning electron microscopy, metallography, and hardness traverses were used to characterize the hole surfaces. Consideration is given to the kind of fatigue test that might be used to evaluate the surface integrity of a small, deep hole.

Fuller, J.E.

1980-01-01

214

A miniaturized EDM device suitable to fixing on a robot  

NASA Astrophysics Data System (ADS)

A miniaturized EDM (Electro Discharge Machining) device has been designed which is suitable to fixing on robot, and the whole system can motion mobile working. A novel control strategy of differential driving principle has been presented in order to solve the problem that electrode can't be revolved owing compact size has been resolved. Coaxial forced vibration of electrode is benefit for the evacuation of debris, and it helps to achieve stable and efficient machining. Analysis of harmonic response and the theoretical value of amplitude have been carried out. The optimal design of ultrasonic motor has been implemented using animate function of ANSYS and optimal design means, and the interference between teeth of stator has been avoided. Auto-frequency tracking has been completed, and electrode lateral vibration of electrode has been eliminated. Finally, the holes with figures of ?85?m circle, Y have been machined.

Tang, Yongjun; Guo, Zhongning; Zhang, Yongjun

2007-10-01

215

Influence of kerosene and distilled water as dielectrics on the electric discharge machining characteristics of Ti–6A1–4V  

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 Ti–6A1–4V 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

216

A comparative study on the surface integrity of plastic mold steel due to electric discharge machining  

Microsoft Academic Search

The violent nature of the electric discharge machining (EDM) process leads to a unique structure on the surface of a machined\\u000a part. In this study, the influence of electrode material and type of dielectric liquid on the surface integrity of plastic\\u000a mold steel samples is investigated. The results have shown that regardless of the tool electrode and the dielectric liquid,

Bülent Ekmekci; Oktay Elkoca; Abdulkadir Erden

2005-01-01

217

Nanoindentation characterization of surface layers of electrical discharge machined WC–Co  

Microsoft Academic Search

This study applies nanoindentation and other analysis techniques to investigate the influence of wire electrical discharge machining (EDM) process on the structure and properties of machined surface layers of WC–Co composites. Multiple indents were conducted on the cross-section of the surface recast layer, sub-surface heat-affected zone, and bulk material. The energy disperse X-ray spectrometry and X-ray diffraction were used to

Jun Qu; Laura Riester; Albert J. Shih; Ronald O. Scattergood; Edgar Lara-Curzio; Thomas R. Watkins

2003-01-01

218

Typical Metrology of Micro-Hole Arrays Made in Stainless Steel Foils by Two-Stage Micro-EDM  

Microsoft Academic Search

Two-stage micro-EDM utilises one machine to fabricate electrodes and a second machine to manufacture holes. The diameter and taper of a hole are dependent on the accuracy of the electrode fabrication which has now been quantified. The accuracy of hole positioning has also been measured using commercial equipment in a novel application. The surface roughness and uniformity of the internal

D. M. Allen; H. J. A. Almond; J. S. Bhogal; A. E. Green; P. M. Logan; X. X. Huang

1999-01-01

219

A neural network process model for abrasive flow machining operations  

Microsoft Academic Search

This paper describes the development of a predictive process modeling system for the abrasive flow machining (AFM) process. This process is used for polishing and surface removal of workpieces with an internal flow path. The core of the process modeling system is a set of neural network models that predicts surface finish and dimensional change. These neural network models are

Kimberly L. Petri; Richard E. Billo; Bopaya Bidanda

1998-01-01

220

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

221

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.

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

222

Effects of flushing on electro-discharge machined surfaces  

Microsoft Academic Search

Although the influence of flushing on the efficiency and stability of machining conditions in EDM has been extensively investigated, including the effects of the flushing configuration on the wear of the tool and the profile of the workpiece, little has been reported concerning the effects of flushing on the integrity of the electro-discharge machined (EDMed) surfaces. This paper presents the

Y. S. Wong; L. C. Lim; L. C. Lee

1995-01-01

223

Mutations in EDM2 selectively affect silencing states of transposons and induce plant developmental plasticity  

PubMed Central

We previously reported on the A. thaliana gene EDM2, which is required for several developmental processes and race-specific immunity. Although EDM2 encodes a nuclear protein with features commonly observed in epigenetic factors, its role in chromatin silencing remains unknown. Here we demonstrate that silencing states of several transposons in edm2 mutants are altered. Levels of their transcripts anti-correlate with those of the repressive epigenetic marks H3K27me1, H3K9me2, and DNA-methylation at CHG sites. In addition, double mutant analysis revealed epistasis between EDM2 and the major histone H3K9-methyltransferase gene KRYPTONITE/SUVH4 in the control of H3K9me2 and CHG methylation. Moreover, we found that the expressivity of several mutant edm2 phenotypes exhibits stochastic variation reminiscent of mutants of known epigenetic modifiers. We propose that EDM2 affects the expression of transposons and developmentally important genes by modulating levels of repressive chromatin marks in a locus dependent manner.

Tsuchiya, Tokuji; Eulgem, Thomas

2013-01-01

224

Temporal Query Processing and Optimization in Multiprocessor Database Machines  

Microsoft Academic Search

In this paper, we discuss issues involving tempo- ral data fragmentation, temporal query processing, and query optimization in multiprocessor database machines. We propose parallel processing strategies, which are based on partitioning of temporal relations on timestamp values, for multi-way joins (e.g., com- plex temporal pattern queries) and optimization al- ternatives. We analyze the proposed schemes quanti- tatively, and show their

T. Y. Cliff Leung; Richard R. Muntz

1992-01-01

225

Machine tool capability profile for intelligent process planning  

Microsoft Academic Search

An optimized metal cutting process plan can only be developed with an accurate capability profile of a machine tool. Based on the information within this profile, a manufacturing decision making process can ascertain the time and production cost of parts. In this paper, a standardized methodology for modelling manufacturing resources is realized to enable accurate representation of actual resources and

S. T. Newman; A. Nassehi

2009-01-01

226

Electrochemical machining in-process data collection and control  

SciTech Connect

Electrochemical machining (ECM) is a fast and efficient method to fabricate intricate metal parts. However, tooling is often expensive; and electical power consumption is relatively high. The precision of an ECM process is dependent upon several variables which often cannot be predicted in the initial tool design. This leads to iterative tool adjustments until the desired level of precision is achieved. A system was devised to use a computer for collecting data from the ECM process and for monitoring and controlling ECM operations. It is believed that these data collections and analyses will lead to the formulation of algorithms to produce parts with better tolerances and will allow more efficient uses of the ECM machines. One algorithm has been developed to allow the efficient ECM of large-surface-area parts. Such programs and equipment will enhance the competitive position of the ECM process in machining applications previously performed by more conventional methods while minimizing electrical power consumption.

Neal, R.E.

1980-09-01

227

Microelectro discharge machining: an innovative method for the fabrication of 3D microdevices  

NASA Astrophysics Data System (ADS)

This paper reports on the potential of microelectro discharge machining (?EDM) as an innovative method for the fabrication of 3D microdevices. To demonstrate the wide capabilities of ?EDM two different high-potential 3D microsystems - a microfluidic device for the dispersion of nanoparticles and a star probe for microcoordinate metrology - are presented. For the fabrication of these microdevices a ?EDM-milling machine with integrated microwire electro discharge grinding (?WEDG) module is utilized. To gain optimized process conditions as well as a high surface quality an adequate adaption of the single erosion parameters such as energy, pulse frequency and spark gap has to be carried out and are discussed below. The dispersion micromodule is used for pharmaceutical screening applications in a high pressure range up to 2000 bar. At the channel bottom a surface roughness of Ra = 80 nm is achieved. In case of the star probe it is possible to produce shaft and sphere out of one piece. The fabricated stylus elements have sphere diameters of 40-200 ?m. For both applications ?EDM offers a flexible, precise, effective and cost-efficient fabrication method for the machining of hard and resistant materials.

Lesche, Claudia; Krah, Thomas; Büttgenbach, Stephanus

2011-05-01

228

Experimental study on the machining of a shaped hole in Ni-based super-heat-resistant alloy  

Microsoft Academic Search

This paper presents an experimental study on the machining methods for a shaped hole in Ni-based super-heat-resistant alloys Inconel 718 and Waspaloy. The feasibility of using milling or\\/and grinding as an alternative for the current EDM process to machine shaped holes is assessed by observing the wear and breakage of the cutting tools and grinder and analyzing the hole surface

X Wei

2002-01-01

229

Self-modulating abrasive medium and its application to abrasive flow machining for finishing micro channel surfaces  

Microsoft Academic Search

This study developed a self-modulating abrasive medium whose viscosity and fluidity can be adjusted during the processing\\u000a period. The complex micro channel was fabricated on the stainless steel (SUS304) by using wire electrical discharge machining\\u000a (wire-EDM). An experiment of employing abrasive flow machining (AFM) was conducted to evaluate the characteristics of various\\u000a levels of roughness and finishing of the micro

Hsinn-Jyh Tzeng; Biing-Hwa Yan; Rong-Tzong Hsu; Yan-Cherng Lin

2007-01-01

230

Wear Properties of Surface Modified Hard Layers Using Electrical Discharge Machine  

Microsoft Academic Search

Recently hard layers have tried to be formed using electrical discharge machines (EDMs) which are mainly used now for material removal. The time and cost of producing dies and machine parts can be greatly reduced when the same EDM is used as the main plant machine in die making and surface modification. The wear properties of hard layers formed on

Koei Matsukawa; Katsunori Satoh; Akihiro Goto; Nagao Saito; Naotake Mohri

2008-01-01

231

Effect of electrical discharge machining on the characteristics of carbon fiber reinforced carbon composites  

Microsoft Academic Search

This work investigated electrical discharge machining (EDM) of carbon fiber reinforced carbon composite material. The characteristics of composites machined by EDM were studied in terms of machining parameters. An empirical model of the composites was also proposed based on the experimental data. The composite material was produced by an electrical discharge sinker using a graphite electrode. The workpiece surface and

Y. H. Guu; H. Hocheng; N. H. Tai; S. Y. Liu

2001-01-01

232

Study of the Effect of Machining Parameters on the Machining Characteristics in Electrical Discharge Machining of Fe-Mn-Al Alloy  

Microsoft Academic Search

In this work we investigated the electrical discharge machining (EDM) of a Fe-Mn-Al alloy. The surface phenomena caused by EDM were studied in terms of machining parameters. An empirical model of the Fe-Mn-Al alloy was also proposed based on the experimental data. Experimental results indicate that the higher the discharge energy, the faster the machining time. This treatment introduces machining

Y. H. Guu; C. Y. Chou; Su-tang Chiou

2005-01-01

233

In-process machine tool vibration cancellation using PMN actuators  

NASA Astrophysics Data System (ADS)

At present, the machine tool technology in the US is not in the state-of-the-art of leading international competitors. Conventional machine tools under use are being pushed into their machining accuracy limits. There is a pressing need calling for revitalizing the machine tool industry. This paper presents, a mechatronic system developed for reducing tool vibration during machining. It consists of electrical and mechanical components, and is realized by placing electrically driven electrostrictive actuators in a specially designed tool post mechanical structure. The linear neural network controller, namely, digital filters, are implemented using a signal processing board. The experimental investigation is conducted in two stages. In the first stage, a test bed is established to use an electro-magnetic shaker to resemble the excitation of cutting force acting on the tool. In the second stage, experiments were conducted using a lathe on the shop floor. In-process vibration cancellation was observed. In the laboratory experiment, a percent reduction in the 90 percent was possible using a feedforward scheme. The improvement in surface roughness during the turning operation was confirmed from measurements of surface roughness profiles.

Eshete, Zelalem; Zhang, Guangming

1996-12-01

234

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

235

Single machine scheduling problems with position-dependent processing times  

Microsoft Academic Search

We consider single machine scheduling problems in which the processing time of a job depends on its position in a processing\\u000a sequence. The objectives are to minimize the weighted sum of completion times, to minimize the maximum lateness and to minimize\\u000a the number of tardy jobs. For some special cases, we prove that the weighted shortest processing time (WSPT) rule,

Ji-Bo Wang; Li-Yan Wang; Dan Wang; Xiao-Yuan Wang; Wen-Jun Gao; Na Yin

2009-01-01

236

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

237

Process for Machine for Segregating Bark from Wood Chips.  

National Technical Information Service (NTIS)

The patent application is concerned with a process and machine which segregates whole-tree chips into foliage, wood chips, bark/wood chips and bark chips at a much higher volume than previously possible. Chips are spread over a continuously moving wire me...

J. A. Sturos J. R. Erickson R. A. Arola G. J. Gorsalitz

1975-01-01

238

Artificial neural networks and machine learning for man-machine-interfaces - processing of nervous signals  

Microsoft Academic Search

Recently, Man-Machine-Interfaces contacting the nervous system in order to extract information resp. to introduce information gain more and more in importance. In order to establish systems like neural prostheses or Brain-Computer-Interfaces, powerful (real time) algorithms for processing nerve signals or their field potentials are required. Another important point is the introduction of information into nervous systems by means like functional

Martin Bogdan; Michael Bensch

2006-01-01

239

High resolution lithography-compatible micro-electro-discharge machining of bulk metal foils for micro-electro-mechanical systems  

NASA Astrophysics Data System (ADS)

The application of batch mode micro-electro-discharge machining (microEDM) to the fabrication of micro-electro-mechanical systems has opened the door to lithographically compatible precision machining of all bulk metals. High volume applications in biomedical, communications, and consumer electronics devices are enabled by this technology. This dissertation explores the capabilities, limitations, and further improvement of high density batch mode microEDM. There are four parts to this effort described below. A machining resolution study of high density features in stainless steel identifies the design space. Lithographically fabricated copper tools with single cross, parallel line, and circle/square array features of 5--100microm width and 5--75microm spacing were used. The observed discharge gap varies with shape, spacing, and feature location from 3.8--8microm. As tool feature density is increased, debris accumulation effects begin to dominate, eventually degrading both tool and workpiece. Two new techniques for mitigating this debris build-up are separately investigated. The first is a silicon passivation coating which suppresses spurious discharges triggered from the sidewalls of the machining tool. By this method, for high density batch machining, mean tool wear rate decreases from a typical rate of about 34% to 1.7% and machining non-uniformity reduces from 4.9microm to 1.1microm across the workpiece. The second involves a two-step machining process that enhances the hydraulic removal of machining debris and therefore throughput. Wireless RF signals are inherently emitted by the micro-discharge process. This thesis describes the first reported wireless detection of debris accumulation during microEDM, enabling direct monitoring of machining quality in real time with 5dBm signal drop. The first wireless detection of the interface between two stacked metals during microEDM is also reported giving a 10dBm signal change. The technique enables direct monitoring of the discharge without the influence of terminal parasitics. Finally, the first study of the residual stress due to the recast layer left behind by microEDM is presented. The recast layer stress-thickness product ranged from 0.5--6 GPa-microm for discharge energies from 0.03--20microJ. The recast layer thickness ranges from 0.2--3.3microm. Low energy discharges allow precision microstructures to be fabricated from bulk metals. Application of microEDM technology to RF switches and stents is in the appendices.

Richardson, Mark Thomas

240

T700 Turbine Nozzle Manufacturing Technology Program. Computer Assisted EDM. Cooling Flow Measurement by IR. Automated Optical Area Measurement.  

National Technical Information Service (NTIS)

This program consisted of three separate tasks relative to the improvement of T700 turbine nozzle manufacturing process. (1) Computer Assisted EDM - This report documents a series of four experiments performed at the Manufacturing Technology Laboratory in...

G. R. Dearth T. Bantel D. Mack V. Bolduc

1981-01-01

241

Embedded fuzzy-control system for machining processes  

Microsoft Academic Search

In this paper a fuzzy-control system has been designed, implemented and embedded in an open CNC. The integration process, design steps and results of applying an embedded fuzzy-control system are shown through the example of real machining operations. The controller uses internal CNC signals (i.e. spindle-motor current) that are gathered and mathematically processed by means of an integrated application. The

R. E. Haber; J. R. Alique; A. Alique; J. Hernández; R. Uribe-Etxebarria

2003-01-01

242

EDMS: what it was, is, and could be.  

PubMed

The decision to implement an Electronic Document Management System (EDMS) should not be made lightly. Such is the advice of a health are provider organization that pioneered the technology a decade ago. University Health Systems of Eastern Carolina's largest facility, Pitt County Memorial Hospital (PCMH), implemented an EDMS in February 1992 and converted to its current EDMS in December 1999. This article describes PCMH's transition from paper to automation, the many trials along the way, and the advantages an EDMS offers. PMID:12402635

Foster, Jean T

2002-08-01

243

Parameter optimization of wire electric discharge machining process using GA and PSO  

Microsoft Academic Search

Wire Electric Discharge Machining (WEDM) is one of the important non-traditional machining processes for machining of intricate profiles in conductive and difficult to machine materials. The machining performance of this process largely depends on various process parameters, such as applied voltage, ignition pulse current, pulse-off time, pulse duration, serve controlled reference mean voltage, servo-speed variation, wire speed, wire tension and

Pandu R. Vundavilli; J. Phani Kumar; Ch. Sai Priyatham

2012-01-01

244

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

245

Micro-EDM for Three-Dimensional Cavities - Development of Uniform Wear Method -  

Microsoft Academic Search

In this paper, we present a new method, called uniform wear method, for 3D micro-EDM. Simple electrodes such as with round or rectangular section are used. Uniform wear at the end of the electrode was realized by layer-by-layer machining. This maintains the original electrode shape and converts the three dimensional electrode wear to a linear one. By compensating the linear

Z. Y. Yu; T. Masuzawa; M. Fujino

1998-01-01

246

Wear resistance of copper EDM tool electrode electroformed from copper sulfate baths and pyrophosphate baths  

Microsoft Academic Search

Electroforming copper from the copper sulfate baths or the pyrophosphate baths is one of commonly used methods for manufacturing\\u000a electro-discharge machining (EDM) tool electrode, in particular for the fabrication of micro- and meso-scale tool electrodes\\u000a with complex cross-section, but few literature on the electrode-wear performance of electroformed copper electrode has been\\u000a available until today. To better select copper tool electrode

Ping Mei Ming; Di Zhu; Yong Bin Zeng; Yang Yang Hu

2010-01-01

247

A passivated electrode batch \\/spl mu\\/EDM technology for bulk metal transducers and packages  

Microsoft Academic Search

Batch mode micro-electro-discharge machining (muEDM) is a lithography-compatible microfabrication method suitable for making devices from bulk metals, including stainless steel. In high-density patterns, spurious discharges through debris can cause workpiece edge rounding, fast tool wear, and mushroom-shaped metal recasting of the tool. This paper reports a Si coating technique that acts as a discharge barrier on the sidewalls of batch

Mark T. Richardson; Yogesh B. Gianchandani

2005-01-01

248

Material removal rate and electrode wear study on the EDM of silicon carbide  

Microsoft Academic Search

In this work, a material removal rate (MRR) and electrode wear (EW) study on the die-sinking electrical discharge machining (EDM) of siliconised or reaction-bonded silicon carbide (SiSiC) has been carried out. The selection of the above-mentioned conductive ceramic was made taking into account its wide range of applications in the industrial field: high-temperature gas turbines, bearings, seals and lining of

C. J. Luis; I. Puertas; G. Villa

2005-01-01

249

Materials processing and machine applications of bulk HTS  

NASA Astrophysics Data System (ADS)

We report a refrigeration system for rotating machines associated with the enhancement of the trapped magnetic flux of bulk high-temperature superconductor (HTS) field poles. A novel cryogenic system was designed and fabricated. It is composed of a low-loss rotary joint connecting the rotor and a closed-cycle thermosiphon under a GM cryocooler using a refrigerant. Condensed neon gas was adopted as a suitable cryogen for the operation of HTS rotating machines with field poles composed of RE-Ba-Cu-O family materials, where RE is a rare-earth metal. Regarding the materials processing of the bulks HTS, thanks to the addition of magnetic particles to GdBa2Cu3O7 - d (Gd123) bulk superconductors an increase of more than 20% in the trapped magnetic flux density was achieved at liquid nitrogen temperature. Field-pole Gd123 bulks up to 46 mm in diameter were synthesized with the addition of Fe-B alloy magnetic particles and assembled into the synchronous machine rotor to be tested. Successful cooling of the magnetized rotor field poles down to 35 K and low-output-power rotating operation was achieved up to 720 rpm in the test machine with eight field-pole bulks. The present results show a substantial basis for making a prototype system of rotating machinery of applied HTS bulks.

Miki, M.; Felder, B.; Tsuzuki, K.; Xu, Y.; Deng, Z.; Izumi, M.; Hayakawa, H.; Morita, M.; Teshima, H.

2010-12-01

250

Objective ink color comparison through image processing and machine learning.  

PubMed

Making changes or additions to written entries in a document can be profitable and illegal at the same time. A simple univariate approach is first used in this paper to quantify the evidential value in color measurements for inks on a document coming from a different or the same source. Graphic, qualitative discrimination is then obtained independently by applying color deconvolution image processing to document images, with parameters optionally optimized by support vector machines (SVM), a machine learning method. Discrimination based on qualitative results from image processing is finally compared to the quantitative results of the statistical approach. As color differences increase, optimized color deconvolution achieves qualitative discrimination when the statistical approach indicates evidence for the different source hypothesis. PMID:23380063

Berger, Charles E H

2012-09-24

251

Optimal process planning for a combined punch-and-laser cutting machine using ant colony optimization  

Microsoft Academic Search

A machine that performs both punching and laser-cutting operations is referred as combined punch-and-laser machine. Such a machine has been in the market for about two decades. Although process-planning tools have been used on such a combined machine, the optimization of process planning dedicated to combined machines, based on our literature search results, has never been directly studied. This work

G. G. Wang; S. Q. XIEz

2005-01-01

252

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; João R. Ferreira; Messias B. Silva; Anderson P. Paiva; Pedro Paulo Balestrassi

2010-01-01

253

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

254

Analysis of EDM calibration measurements — program CALORY  

Microsoft Academic Search

A new computer program for the adjustment of EDM calibration measurements using least squares has been developed. This program implements the analysis procedures recommended to the National Standards Commission and provides the user with knowledge of the uncertainty of the determined instrument correction.

T. G. Norton

1986-01-01

255

In-process machine tool vibration cancellation using PMN actuators  

Microsoft Academic Search

At present, the machine tool technology in the US is not in the state-of-the-art of leading international competitors. Conventional machine tools under use are being pushed into their machining accuracy limits. There is a pressing need calling for revitalizing the machine tool industry. This paper presents, a mechatronic system developed for reducing tool vibration during machining. It consists of electrical

Zelalem Eshete; Guangming Zhang

1996-01-01

256

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 (WC–Co), 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

257

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

258

Experimental characterization of dry EDM performed in a pulsating magnetic field  

Microsoft Academic Search

This paper presents an investigation of the hybrid dry EDM process performed in a pulsating magnetic field for improving process performance. In this study, the pulsating magnetic field is applied tangential to the electric field, for increasing the movement of electrons and degree of ionization in the plasma. Experiments with parametric variations showed that this hybrid approach leads to productivity-improvement

S. Joshi; P. Govindan; A. Malshe; K. Rajurkar

2011-01-01

259

Machine vision for process industries: Monitoring, control, and optimization of visual quality of processes and products  

Microsoft Academic Search

A new paradigm for machine vision for the process industries is proposed, and a framework is illustrated through several industrial applications. The framework is designed for handling the stochastic nature of the visual quality of processes and products in the process industries. In this thesis visual quality means spectral (i.e., color) and\\/or textural appearance of processes and products where the

June Liu

2005-01-01

260

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

261

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

262

Effects of electrical discharge energy on machining performance and bending strength of cemented tungsten carbides  

Microsoft Academic Search

This work elucidates the effect of electrical discharge energy on surface crack and bending strength of cemented tungsten carbide by electrical discharge machining (EDM). Cemented tungsten carbides graded K10 and P10 were used as workpiece materials, and the machining parameters of EDM were varied to study the effects of electrical discharge energy on material removal rate (MRR) and surface roughness.

Yan-Cherng Lin; Lih-Ren Hwang; Chao-Hsu Cheng; Pao-Lin Su

2008-01-01

263

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

SciTech Connect

The demand and use of precision grinding of structural ceramics continue to increase as the worldwide advanced ceramic industry surpasses $20 billion is sales. Included in this industry are engineering structural ceramics, electronic ceramics, bioceramics and others. These materials are used in applications such as engine components, casting and extrusion dies, bearings, medical implants, nozzles, thermal insulators, and more. Along with the variety of ceramic applications comes a broad range of precision requirements, which in turn leads to various required processes to accommodate a spectrum of specifications. A process for grinding ceramic components to micrometer tolerances was employed and further developed at Lawrence Livermore National Laboratory for two separate grinding projects.

Piscotty, M.A.; Davis, P.J.; Saito, T.T.; Blaedel, K.L.; Griffith, L.

1997-08-01

264

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

2010-11-18

265

White Layer Composition, Heat Treatment, and Crack Formation in Electric Discharge Machining Process  

NASA Astrophysics Data System (ADS)

Characteristics of electric discharge machined (EDM) surfaces of normalized, quenched, and quenched and tempered-treated steels in kerosene and deionized-water dielectric liquids are investigated. Optical microscopy, scanning electron microscopy (SEM) and X-ray diffractometry are employed to analyze the machined surface. Surface cracks are examined in terms of white layer composition, heat treatment of the workpiece material, and operational parameters used, such as average discharge current and pulse-on duration. The present results reveal that base material properties and white layer composition have a distinctive function on crack formation that results in different crack network layouts on the surface and penetration depths in the substrate. Surface cracks, which initiate at the surface, travel down perpendicularly toward the interferential zone, and terminate at this interference, are mainly formed due to an increase in nonhomogeneities of metallurgical phases within the white layer. Such cracks are usually encountered on the surfaces when machining is performed in a hydrocarbon-based dielectric liquid using high pulse-on duration and low average discharge current. On the other hand, penetrating cracks, which penetrate the entire white layer thickness to an extent into the parent material, are mainly formed due to contraction of the recast structure joined to the circumferential edge of a crater rim during solidification. This type of crack is common when machining is performed in deionized water and the work material is brittle. Crack penetration depth is found to be proportional to the used pulse energy, and its path has a tendency to form parallel cracks to the machined surface at decreased pulse-on duration.

Ekmekci, Bülent

2009-02-01

266

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

267

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

268

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

269

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; Takeda, Kenya [NTT Co. Ltd., Chiba (Japan); Nagamatsu, Takashi [Mitsubishi Heavy Industries, Ltd., Tokyo (Japan); Wakayama, Toshio [Mitsubishi Electric Corp., Kamakura, Kanagawa (Japan); Kimura, Iwane [Osaka Inst. of Tech., Hirakata, Osaka (Japan); Shinbo, Tetsuya [Komatsu Co. Ltd., Kanagawa (Japan)

1997-03-01

270

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

271

Single CNC machine scheduling with controllable processing times to minimize total weighted tardiness  

Microsoft Academic Search

Advanced manufacturing technologies, such as CNC machines, require significant investments, but also offer new capabilities to the manufacturers. One of the important capabilities of a CNC machine is the controllable processing times. By using this capability, the due date requirements of customers can be satisfied much more effectively. Processing times of the jobs on a CNC machine can be easily

M. Selim Akturk; Taylan Ilhan

2011-01-01

272

Design and Testing of a Friction Stir Processing Machine for Laboratory Research  

SciTech Connect

This presentation describes the design, fabrication and testing of a friction stir processing machine. The machine is intended to be a flexible research tool for a broad range of friction stir processing studies. The machine design also addresses the need for an affordable, robust design for general laboratory use.

Karen S. Miller; Rodney J. Bitsoi; Eric D. Larsen; Herschel B. Smartt

2006-08-01

273

Evaluation of near-dry machining effects on gear milling process efficiency  

Microsoft Academic Search

One of the main environmental pollution sources related to machine building industry is the huge amount of cutting fluids which are supplied during the machining processes. In order to avoid the problems induced by cutting fluids' usage, considerable progress has been recently made in the field of near-dry machining (NDM). Converting conventional processes to minimal quantity lubrication (MQL) methods imposes

Domnita Fratila

2009-01-01

274

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

Code of Federal Regulations, 2013 CFR

...operation of power-driven meat-processing machines and occupations involving slaughtering...operation of power-driven meat-processing machines and occupations involving slaughtering...products and the operation of lard-roll machines. (3) All occupations...

2013-07-01

275

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 ±5.7stat±1.5syst) 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

276

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

277

Modeling and Analysis of Machinability Evaluation in the Wire Electrical Discharge Machining (WEDM) Process of Aluminum Oxide-Based Ceramic  

Microsoft Academic Search

The wire electrical discharge machining (WEDM) allowed success in the manufacture of the hard, fragile, and materials difficult to cut, especially for electroconductive ceramic materials. In this study, the mathematical models of material removal rate (MRR) and surface roughness (SR) used for the machinability evaluation in the WEDM process of aluminum oxide-based ceramic material (Al2O3 + TiC) have been carried out. The

Kuang-Yuan Kung; Ko-Ta Chiang

2008-01-01

278

Support Vector Machines for 3D Shape Processing  

Microsoft Academic Search

We propose statistical learning methods for approximating implicit surfaces and computing dense 3D deformation fields. Our approach is based on Support Vector (SV) Machines, which are state of the art in machine learning. It is straightforward to implement and computationally competitive; its parameters can be automatically set using standard machine learning methods. The surface approximation is based on a modified

Florian Steinke; Bernhard Schölkopf; Volker Blanz

2005-01-01

279

Fabrication of Wire Saw with Patterned Hard Bumps by Electrical Discharge Machining with Powder Suspended in Working Oil  

Microsoft Academic Search

This paper deals with a fabrication method of a wire saw by electrical discharge machining (EDM). Hard bumps were discretely patterned on the surface of a thin stainless steel wire by EDM with titanium powder suspended in working oil. With an increase of the machining time, the average of the bump height was increased and no removal was observed. The

Katsushi Furutani; Yasuo Murase

280

Microelectro discharge machining: an innovative method for the fabrication of 3D microdevices  

Microsoft Academic Search

This paper reports on the potential of microelectro discharge machining (muEDM) as an innovative method for the fabrication of 3D microdevices. To demonstrate the wide capabilities of muEDM two different high-potential 3D microsystems - a microfluidic device for the dispersion of nanoparticles and a star probe for microcoordinate metrology - are presented. For the fabrication of these microdevices a muEDM-milling

Claudia Lesche; Thomas Krah; Stephanus Büttgenbach

2011-01-01

281

Intrinsic innovations of die sinking electrical discharge machining technology: estimation of its impact  

Microsoft Academic Search

The die sinking version of electrical discharge machining (EDM) is a current manufacturing technology widely disseminated\\u000a in several industrial sectors. In the recent past, developments in the high-speed milling (HSM) have narrowed the EDMs’ traditional\\u000a application domains. As a result, a strong research effort has been focused on EDM leading to the reduction of the operation\\u000a time and cost and

P. Peças; E. Henriques

2009-01-01

282

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

283

Study on Nano EDM Using Capacity Coupled Pulse Generator  

Microsoft Academic Search

This paper describes the development of a pulse generator for nano EDM using a capacity coupling method. To obtain discharge craters of nanometer diameter, a pulse generator was coupled to the tool electrode by a capacitor. Since the influence of the stray capacitance in the electric feeders can be eliminated, the discharge energy can be minimized to accomplish nano EDM.

M. Kunieda; A. Hayasaka; X. D. Yang; S. Sano; I. Araie

2007-01-01

284

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

285

Information integration and diagnosis analysis of equipment status and production quality for machining process  

NASA Astrophysics Data System (ADS)

Machining status monitoring technique by multi-sensors can acquire and analyze the machining process information to implement abnormity diagnosis and fault warning. Statistical quality control technique is normally used to distinguish abnormal fluctuations from normal fluctuations through statistical method. In this paper by comparing the advantages and disadvantages of the two methods, the necessity and feasibility of integration and fusion is introduced. Then an approach that integrates multi-sensors status monitoring and statistical process control based on artificial intelligent technique, internet technique and database technique is brought forward. Based on virtual instrument technique the author developed the machining quality assurance system - MoniSysOnline, which has been used to monitoring the grinding machining process. By analyzing the quality data and AE signal information of wheel dressing process the reason of machining quality fluctuation has been obtained. The experiment result indicates that the approach is suitable for the status monitoring and analyzing of machining process.

Zan, Tao; Wang, Min; Hu, Jianzhong

2010-12-01

286

Study of the recast layer of a surface machined by sinking electrical discharge machining using water-in-oil emulsion as dielectric  

Microsoft Academic Search

Electrical discharge machining (EDM) caused a recast layer to form at the machined surface of the workpiece. The characteristics of the recast layer have a great relationship with the type of dielectric. The research work in this paper aims to acquire a profound knowledge of the recast layers of a surface machined by sinking EDM using water-in-oil (W\\/O) emulsion as

Yanzhen Zhang; Yonghong Liu; Renjie Ji; Baoping Cai

2011-01-01

287

APPLICATION OF HYBRID GRINDING PROCESSES FOR FINISH MACHINING OF SURFACES OF SUPERHARD MATERIAL  

Microsoft Academic Search

Hybrid grinding processes consist in a simultaneous use of different energy forms for the removal of machining allowance. Combination of mechanical, physicochemical and electric impacts on the machined material brings about such phenomena as plastic flow, mechanical destruction, warming, evaporation and dissolving in the processed zone. These processes affect, among others, properties of this material and determine the intensity and

A. Golabczak

288

PROCESS MONITORING OF ABRASIVE FLOW MACHINING USING A NEURAL NETWORK PREDICTIVE MODEL  

Microsoft Academic Search

This paper discusses the preliminary development of a neural network based process monitor and off-line controller for abrasive flow machining of automotive engine intake manifolds. The process is only observable indirectly, yet the time at which machining achieves the specified air flow rate must be estimated accurately. A neural network model is used to estimate when the process has achieved

Sarah S. Y. Lam; Alice E. Smith

1997-01-01

289

A novel electrical power supply for electrothermal and electrochemical removal machining methods  

Microsoft Academic Search

For electrically conductive materials Electrical Discharge Machining (EDM), electrochemical machining (ECM) and Electrochemical Discharge Machining (ECDM) constitute a procedure to manipulate materials that are difficult to machine using conventional machining methods. Due to their different electrical behavior all three methods would usually require dedicated power supplies. This paper introduces and analyzes a novel low-loss power supply which can be used

David Tastekin; Harry Krötz; Clemens Gerlach; Jörg Roth-Stielow

2009-01-01

290

Self-running type electrical discharge machine using impact drive mechanism  

Microsoft Academic Search

Summary form only given. Electrical discharge machining (EDM) is one of the best ways to machine fine structures because tools do not break, no burr is generated, and machinability does not depend on the hardness of a conductive workpiece. A self-running electrical discharge machine is developed to machine fine structures on a local area of a large workpiece. This electrical

Katsushi Furutani; Naotake Mohri; Toshiro Higuchi

1997-01-01

291

Machine vision processing\\/selection in printed circuit board manufacturing  

Microsoft Academic Search

Machine vision applications are common in the manufacturing of PWBs. Machine vision systems are used in the placement of surface mount devices with lead pitch of 0.025 inch or less. There are two steps in the successful placement of surface mount devices, as follows: (a) The location of the device on the vacuum tip which picks and places the device

A. Trivedi; Paul Cheng-Hsin Liu

1997-01-01

292

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 Subirón

2010-01-01

293

Machining Performance Optimization in End ED Milling and Mechanical Grinding Compound Process  

Microsoft Academic Search

Silicon carbide (SiC) ceramic has been widely used in modern industry for its excellent physical and mechanical properties. However, SiC ceramic is difficult to machine owing to its high hardness and brittleness. This paper presents a novel compound process that integrates end electric discharge (ED) milling and mechanical grinding to machine SiC ceramic. The process is able to effectively machine

Renjie Ji; Yonghong Liu; Yanzhen Zhang; Fei Wang; Baoping Cai; Xin Dong

2011-01-01

294

Machining Performance Optimization in End ED Milling and Mechanical Grinding Compound Process  

Microsoft Academic Search

Silicon carbide (SiC) ceramic has been widely used in modern industry for its excellent physical and mechanical properties. However, SiC ceramic is difficult to machine owing to its high hardness and brittleness. This article presents a novel compound process that integrates end electric discharge (ED) milling and mechanical grinding to machine SiC ceramic. The process is able to effectively machine

Renjie Ji; Yonghong Liu; Yanzhen Zhang; Fei Wang; Baoping Cai; Xin Dong

2012-01-01

295

Three-Dimensional Micromachining by Machine Tools  

Microsoft Academic Search

Machining technologies for three-dimensional microproducts are summarized by focusing on the methods using tools. After a discussion on the problems and the basic strategy concerning micromachining, promising methods for machining convex and concave shapes are introduced and discussed with respect to their state of the art. The methods introduced include WEDG, EDM, grinding, cutting, WECG, MEDM, microdrilling, micromilling, MUSM, micropunching,

T. Masuzawa; H. K. Tönshoff

1997-01-01

296

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

297

Studies on the fabrication of metallic bipolar plates—Using micro electrical discharge machining milling  

Microsoft Academic Search

Owed to the advantages of highly precise and flexible machining, micro electrical discharge machining milling (micro EDM milling) can machine higher aspect ratio micro flow channels than the micro flow channels made from etching or deposition techniques, which have aspect ratio of only 0.5–0.7.This study reports on the production of micro flow channels in metallic bipolar plates, using micro EDM

Jung-Chung Hung; Tzu-Chun Yang; Kuo-chou Li

298

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

299

MEASUREMENT OF INDOOR AIR EMISSIONS FROM DRY-PROCESS PHOTOCOPY MACHINES  

EPA Science Inventory

The article provides background information on indoor air emissions from office equipment, with emphasis on dry-process photocopy machines. The test method is described in detail along with results of a study to evaluate the test method using four dry-process photocopy machines. ...

300

Improvement of surface integrity of electro-chemical discharge machining process using powder-mixed electrolyte  

Microsoft Academic Search

A new method has been investigated to improve the surface integrity of electro-chemical discharge machining (ECDM) process by use of conductive particles in the electrolyte. In conventional ECDM processes the generation of fine sparks with uniform energy has been most desired technique to improve the machining efficiency and the surface quality. However, precise control of the spark generations in ECDM

Min-Seop Han; Byung-Kwon Min; Sang Jo Lee

2007-01-01

301

The effects of machining process variables and tooling characterisation on the surface generation  

Microsoft Academic Search

The paper presents a novel approach for modelling and simulation of the surface generation in the machining process. The approach, by integrating a dynamic cutting force model, regenerative vibration model, machining system response model and tool profile model, models the complex surface generation process. Matlab Simulink is used to interactively perform the simulation in a user-friendly, effective and efficient manner.

X. Luo; K. Cheng; R. Ward

2005-01-01

302

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

303

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

304

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

305

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

306

Flow shop scheduling with two batch processing machines and nonidentical job sizes  

Microsoft Academic Search

A batch processing machine can process several jobs simultaneously. In this research, we consider the problem of a two-stage\\u000a flow shop with two batch processing machines to minimize the makespan. We assume that the processing time of a batch is the\\u000a longest processing time among all the jobs in that batch and the sizes of the jobs are nonidentical. There

H. S. Mirsanei; B. Karimi; F. Jolai

2009-01-01

307

Single-machine scheduling problems with time and position dependent processing times  

Microsoft Academic Search

We consider single-machine scheduling problems with time and position dependent job processing times. In many industrial settings,\\u000a the processing time of a job changes due to either job deterioration over time or machine\\/worker’s learning through experiences.\\u000a In the models we study, each job has its normal processing time. However, a job’s actual processing time depends on when its\\u000a processing starts

Xingong Zhang; Guangle Yan; Wanzhen Huang; Guochun Tang

2011-01-01

308

Adjustment and readjustment of electrochemical machines and control of the process parameters in machining shaped surfaces  

Microsoft Academic Search

The dimensional accuracy of components obtained as a result of conventional or pulse ECM is affected by random, systematic and regularly varying errors. On the basis of experimental studies, the effect of control parameters such as operating voltage, electrolyte pressure, relative pulse duration, etc., on interelectrode gap size has been revealed, and the tasks of electromechanical machine adjustment and readjustment

Zinovi Brusilovski

2008-01-01

309

Developing a Process Model for Abrasive Flow Machining  

Microsoft Academic Search

\\u000a Abrasive flow machining (AFM) is a unique machining method used to achieve high surface quality on inner, difficult-to-access\\u000a contours and on outside edges. Using AFM, it is possible to deburr complex shaped intersecting holes and to realize pre-defined\\u000a edge rounding on any brittle or hard material. Moreover it is easy to integrate into an automated manufacturing environment.\\u000a Reproducibility of results

E. Uhlmann; V. Mihotovic; H. Szulczynski; M. Kretzschmar

310

PLANS FOR A NEUTRON EDM EXPERIMENT AT SNS  

SciTech Connect

The electric dipole moment of the neutron, leptons, and atoms provide a unique window to Physics Beyond the Standard Model. They are currently developing a new neutron EDM experiment (the nEDM Experiment). This experiment, which will be run at the 8.9 {angstrom} Neutron Line at the Fundamental Neutron Physics Beamline (FNPB) at the Spallation Neutron Source (SNS) at the Oak Ridge National Laboratory, will search for the neutron EDM with a sensitivity two orders of magnitude higher than the present limit. In this paper, the motivation for the experiment, the experimental method, and the present status of the experiment are discussed.

ITO, TAKEYASU [Los Alamos National Laboratory

2007-01-31

311

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

312

TiN coating on an electrical discharge machined WC-Co hardmetal: surface integrity effects on indentation adhesion response  

Microsoft Academic Search

Electrical discharge machining (EDM) is an alternative-shaping route for manufacturing complex component shapes of hard and\\u000a brittle materials such as hardmetals (WC-Co cemented carbides). It is well established that in these materials EDM typically\\u000a induces a heat affected surface layer with poor integrity. This degradation effect may be compensated through specific post-EDM\\u000a surface treatments either by thermomechanical means or material

B. Casas; M. Anglada; V. K. Sarin; L. Llanes

2006-01-01

313

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

314

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

315

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. Künanz

2004-01-01

316

A Comprehensive Market Analysis on Camera and Illumination Sensors for Image Processing and Machine Vision Applications  

Microsoft Academic Search

In the present industrial application space, conventional inspection techniques using manual intervention are getting replaced by automated inspection using image sensors. Image sensors have empowered machines with vision and that has led to increased levels of process automation which used to be manually exhaustive. This paper mainly focuses on the comparative study of Machine Vision hardware aspect specifically on cameras

Ayan Chaki; M. Prashant; P. Sen

2010-01-01

317

Information integration and diagnosis analysis of equipment status and production quality for machining process  

Microsoft Academic Search

Machining status monitoring technique by multi-sensors can acquire and analyze the machining process information to implement abnormity diagnosis and fault warning. Statistical quality control technique is normally used to distinguish abnormal fluctuations from normal fluctuations through statistical method. In this paper by comparing the advantages and disadvantages of the two methods, the necessity and feasibility of integration and fusion is

Tao Zan; Min Wang; Jianzhong Hu

2010-01-01

318

Process Parameters Optimization for Energy Saving in Paper Machine Dryer Section  

Microsoft Academic Search

Due to high energy consumption in the Chinese paper industry, this study considers higher-energy efficiency for the multicylinder dryer section of paper machines. A common situation in the Chinese paper industry is that energy is consumed in extensive mode. In order to improve the energy efficiency of the paper machine dryer section, deeper analysis and optimization of process parameters are

Yugang Li; Huanbin Liu; Jigeng Li; Jinsong Tao

2011-01-01

319

Automatic signal processing of front monitor radar for tunneling machines  

Microsoft Academic Search

It is planned to install a front monitor 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 does not constitute a hyperbola as is the

Toru Sato; Ken-ya Takeda; Takashi Nagamatsu; Toshio Wakayama; Iwane Kimura; Tetsuya Shinbo

1997-01-01

320

Contact condition modelling for machining fixture setup processes  

Microsoft Academic Search

Manufacturing automation often requires high precision and highly accurate equipment to achieve satisfactory performance. In many cases, precision and accuracy depend highly on the surface contact conditions between machine components. Described in this paper is the modelling of the response frequency of a modular fixturing system with multiple components in contact, and it has demonstrated that it is possible to

J. H. Yeh; F. W. Liou

1999-01-01

321

Effect and Control of Chatter Vibrations in Machine Tool Process.  

National Technical Information Service (NTIS)

A theory is formulated using a feedback loop to represent the chatter mechanism. This theory permits the calculation of borderlines of stability for a machine tool system having a structure with n-degrees of freedom. A cutting stiffness table is presented...

G. W. Long R. L. Kegg J. R. Lemon

1965-01-01

322

Experimental Studies on Mechanism of Material Removal in Abrasive Flow Machining Process  

Microsoft Academic Search

In this article, the mechanism of material removal (MR) in Abrasive Flow Machining (AFM) process has been studied. Representative components of pure Aluminum and Brass were processed by AFM under similar process conditions. The processed surfaces were analyzed with the help of Scanning Electron Microscopy (SEM). SEM photographs reveal noticeable difference between abrasion patterns produced on the processed surfaces of

Sehijpal Singh; H. S. Shan; Pradeep Kumar

2008-01-01

323

Study on the nano machining process with a vibrating AFM tip on the polymer surface  

NASA Astrophysics Data System (ADS)

The polymer has been proved to be nano machined by a vibrating tip in tapping mode of Atomic Force Microscope (AFM). The force between the tip and the surface is an important factor which determines success of the machining process. Controlling this force with high accuracy is the foundation of nanomachining in AFM tapping mode. To achieve a deeper understanding on this process, the tip is modeled as a driving oscillator with damping. Factors affecting the nano machining process are studied. The Hertz elastic contact theory is used to calculate the maximum contact pressure applied by the tip which is employed as a criterion to judge the deformation state of the sample. The simulation results show that: The driven amplitude can be used as a main parameter of controlling the machined depth. Sharper tips and harder cantilevers should be used for successful nanomachining with the vibrating tip. Under the same conditions, a larger tip radius will not only result in the machining error, but also lead to failure of the nanomachining process. The higher driving frequency will lead to a larger tapping force. However it cannot be used as a parameter to control the machined depth because of its narrow variation range. But it is a main error source for the nanomachining process in AFM tapping mode. Moreover, a larger Young's modulus polymer sample will induce a smaller machined depth, a larger maximum contact pressure and a bigger tapping force.

Liu, Weitao; Yan, Yongda; Hu, Zhenjiang; Zhao, Xuesen; Yan, Jiucun; Dong, Shen

2012-01-01

324

Direct selective laser sintering of high performance metals: Machine design, process development and process control  

NASA Astrophysics Data System (ADS)

This dissertation describes the development of an advanced manufacturing technology known as Direct Selective Laser Sintering (Direct SLS). Direct SLS is a laser based rapid manufacturing technology that enables production of functional, fully dense, metal and cermet components via the direct, layerwise consolidation of constituent powders. Specifically, this dissertation focuses on a new, hybrid net shape manufacturing technique known as Selective Laser Sintering/Hot Isostatic Pressing (SLS/HIP). The objective of research presented in this dissertation was to establish the fundamental machine technology and processing science to enable direct SLS fabrication of metal components composed of high performance, high temperature metals and alloys. Several processing requirements differentiate direct SLS of metals from SLS of polymers or polymer coated powders. Perhaps the most important distinguishing characteristic is the regime of high temperatures involved in direct SLS of metals. Biasing the temperature of the feedstock powder via radiant preheat prior to and during SLS processing was shown to be beneficial. Preheating the powder significantly influenced the flow and wetting characteristics of the melt. During this work, it was conclusively established that powder cleanliness is of paramount importance for successful layerwise consolidation of metal powders by direct SLS. Sequential trials were conducted to establish optimal bake-out and degas cycles under high vacuum. These cycles agreed well with established practices in the powder metallurgy industry. A study of some of the important transport mechanisms in direct SLS of metals was undertaken to obtain a fundamental understanding of the underlying process physics. This study not only provides an explanation of phenomena observed during SLS processing of a variety of metallic materials but also helps in developing selection schemes for those materials that are most amenable to direct SLS processing. The development of machine, processing and control technologies during this research effort enabled successful production of a number of integrally canned test specimens in Alloy 625 (InconelRTM 625 superalloy) and Ti-6Al-4V alloy. The overall goal of this research was to develop direct SLS of metals armed with a fundamental understanding of the underlying physics. The knowledge gained from experimental and analytical work is essential for three key objectives: machine design, process development and process control. (Abstract shortened by UMI.)

Das, Suman

1998-11-01

325

Processes and equipment for the thermomechanical treatment of machine parts  

NASA Astrophysics Data System (ADS)

The methods and equipment used for the thermomechanical treatment of machine parts are reviewed, with particular attention given to optimal directional hardening according to specific operating conditions. The discussion covers the physical principles underlying directional thermomechanical treatments and the effect of such treatments on the properties and structure of steels. Thermomechanical treatments for cold-mill rolls, springs, parts of case-hardened steels, and parts of large dimensions and complex shapes are discussed.

Shavrin, O. I.

326

Heating mechanism in relation to the laser machining process  

Microsoft Academic Search

Laser workpiece interaction mechanism is an important phenomenon which will assist in the development of laser machining systems.\\u000a The interaction mechanism is generally complicated and depends on the laser and workpiece properties. In the present study\\u000a a mathematical analysis for the laser material removal by evaporation and radial ejection of liquid is carried out. In the\\u000a analysis the time unsteady

Bekir S Yilbas; Ahmet Z Sahin

1993-01-01

327

Digital-Image Processing Improves Man-Machine Communication at a Nuclear Reactor.  

National Technical Information Service (NTIS)

The application of digital image processing to improve man-machine communication in a nuclear reactor control room is illustrated. At the Hanford N Reactor, operated by UNC Nuclear Industries for the United States Department of Energy, in Richland, Washin...

S. A. Cook T. P. Harrington H. Toffer

1982-01-01

328

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

329

Logistics Machining Data.  

National Technical Information Service (NTIS)

Contents: Machining operations; tool geometry; cutting fluids; electrical, chemical, special mechanical and optical machining processes; supplemental machining data and information; economics in machining; instructions in machining; surface finish; numeri...

1966-01-01

330

Robotics, Signal Processing, Decision Making and Self-reproducing Machine Learning  

Microsoft Academic Search

In 2005, inspired by Von Neumannpsilas self-reproducing automata, the author had introduced self-reproducing machine learning (SRML). In this article the author is trying to explore the nature of self-reproducing machine learning, SRML architectures, formal structures, mathematical structures and its integrated systems software engineering principles. The author will demonstrate SRML technology to robotics, image processing, signal processing, Web mining and social

James Kuodo Huang

2008-01-01

331

A transputer-based shuffle-shift machine for image processing and reconstruction  

Microsoft Academic Search

A message-passing multicomputer is presented, and its application to image processing and reconstruction is outlined. The multicomputer may be seen as a one-dimensional array of computing nodes with bidirectional shuffle and shift connections. The resulting shuffle-shift machine is well suited for tasks like image processing and image reconstruction. A sample shuffle-shift machine has been built using transputers. The hardware and

H. Schomberg

1990-01-01

332

An analytical approach for determining the environmental impact of machining processes  

Microsoft Academic Search

This paper presents a model of the environmental impact of machining processes. The analytical model integrates aspects of the process mechanics, wear characteristics and lubricant flows. The quantifiable dimensions in this analysis include energy utilization, process rate, workpiece primary mass flow, and secondary flow of process catalysts. The generation of multiple waste streams can be compared by examining factors such

A. A. Munoz; P. Sheng

1995-01-01

333

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

Code of Federal Regulations, 2010 CFR

...power-driven meat-processing machines and occupations involving...power-driven meat-processing machines and occupations involving...infrequently and for short periods of time. (2) All occupations...the operation of lard-roll machines. (3) All...

2010-07-01

334

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

335

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

336

Feature-based process planning for environmentally conscious machining – Part 1: microplanning  

Microsoft Academic Search

Process planning in environmentally conscious machining involves a multi-objective analysis of manufacturing dimensions that include production rate, quality, process energy and mass of waste streams generated by the process. While there has been a body of work developed in life cycle analysis, one of the critical issues limiting environmental analyses is the material and geometric complexity of engineered components. In

M. Srinivasan; P. Sheng

1999-01-01

337

Single machine scheduling with controllable processing times to minimize total tardiness and earliness  

Microsoft Academic Search

In most deterministic scheduling problems job processing times are considered as invariable and known in advance. Single machine scheduling problem with controllable processing times with no inserted idle time is presented in this study. Job processing times are controllable to some extent that they can be reduced or increased, up to a certain limit, at a cost proportional to the

Vahid Kayvanfar; Iraj Mahdavi; G. H. M. Komaki

338

An Investigation of Machining Characteristics in Micro-scale Milling Process  

SciTech Connect

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 [School of Mechanical Engineering, Pusan National University, San 30, Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of); Kim, Jeong-Suk [School of Mechanical Engineering / Engineering Research Center for Net Shape and Die Manufacturing, Pusan National University, San 30, Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of)

2011-01-17

339

Fabrication of high-aspect-ratio electrode array by combining UV-LIGA with micro electro-discharge machining  

Microsoft Academic Search

In this paper, the combination of UV-LIGA with the Micro electro-discharge machining (Micro-EDM) process was investigated\\u000a to fabricate high-aspect-ratio electrode array, and an easy and rapid process for fabricating ultra-thick SU-8 microstructures\\u000a up to millimeter depth was described. First, the modified UV-LIGA process was used to fabricate the copper hole array, and\\u000a then the hole array electrode was employed as

Yang-Yang Hu; D. Zhu; N. S. Qu; Y. B. Zeng; P. M. Ming

2009-01-01

340

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

341

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

342

Surface Integrity of Hard Metal Parts Machined by WEDM  

Microsoft Academic Search

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

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

2009-01-01

343

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

344

Parameter estimation for abrasive water jet machining process using neural networks  

Microsoft Academic Search

The abrasive water jet machining process, a material removal process, uses a high velocity jet of water and an abrasive particle\\u000a mixture. The estimation of appropriate values of the process parameters is an essential step toward an effective process performance.\\u000a This has led to the development of numerous mathematical and empirical models. However, the complexity of the process confines\\u000a the

Pratik J. Parikh; Sarah S. Lam

2009-01-01

345

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

346

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

347

Integrated machine learning approaches for complementing statistical process control procedures  

Microsoft Academic Search

Although statistical process control (SPC) procedures have played a central role in solving quality problems, their effectiveness is yet to be fully realized in the process industry with large volume data, a lot of dimensions of variables, and complex relationships among processes and variables. To complement SPC procedures, we suggest three integrated methods of inductive learning and neural networks for

Boo-sik Kang; Sang-chan Park

2000-01-01

348

Neural networks with fuzzy Petri nets for modeling a machining process  

NASA Astrophysics Data System (ADS)

The paper presents an intelligent architecture based a feedforward neural network with fuzzy Petri nets for modeling product quality in a CNC machining center. It discusses how the proposed architecture can be used for modeling, monitoring and control a product quality specification such as surface roughness. The surface roughness represents the output quality specification manufactured by a CNC machining center as a result of a milling process. The neural network approach employed the selected input parameters which defined by the machine operator via the CNC code. The fuzzy Petri nets approach utilized the exact input milling parameters, such as spindle speed, feed rate, tool diameter and coolant (off/on), which can be obtained via the machine or sensors system. An aim of the proposed architecture is to model the demanded quality of surface roughness as high, medium or low.

Hanna, Moheb M.

1998-03-01

349

Identification of Symmetric Noncausal Processes: Cross-Directional Response Modelling of Paper Machines  

Microsoft Academic Search

We adapt the maximum likelihood method to treat symmetric noncausal models. Such models govern the cross-directional response of paper machines: they are noncausal in space, not in time. Process symmetry is essential to our methods. We show that every symmetric noncausal process admits a spectrally equivalent causal model, then prove that the maximum likelihood estimate of this causal model converges

R. Bhushan Gopaluni; Philip D. Loewen; Mohammed Ammar; Guy A. Dumont; Michael S. Davies

2006-01-01

350

Scheduling start time dependent tasks with deadlines and identical initial processing times on a single machine  

Microsoft Academic Search

In this paper we study the feasibility problem of scheduling a set of start time dependent tasks on a single machine with deadlines, processing rates and identical initial processing times. First, we show that the cases with arbitrary deadlines are strongly NP-complete. Second, we show that the cases with two distinct deadlines are NP-complete in the ordinary sense. Finally, we

T. C. Edwin Cheng; Qing Ding

2003-01-01

351

Investigation of a novel hybrid process of laser drilling assisted with jet electrochemical machining  

Microsoft Academic Search

Recast layer and spatter are two inherent defects commonly associated with holes produced with laser drilling. This paper reports a novel hybrid process of laser drilling assisted with jet electrochemical machining (JECM-LD) that aims to minimize such defects and improve the quality of laser-drilled holes. The process based on the application of a jet electrolyte, being aligned coaxially with the

Hua Zhang; Jiawen Xu; Jiming Wang

2009-01-01

352

UNIFIED APPROACH AND INTERACTIVE PROGRAM FOR THERMAL ANALYSIS OF VARIOUS MANUFACTURING PROCESSES WITH APPLICATION TO MACHINING  

Microsoft Academic Search

Analytical approach to thermal aspects of various manufacturing processes, such as machining, grinding, polishing, welding, heat treatment, laser processing, and tribology was used by many researchers between the late 1930s and early 1940s. That was the golden period when Blok introduced the heat partition concept in 1937; Jaeger developed the heat source method in 1942; and Rosenthal introduced the moving

Ranga Komanduri; Zhen Bing Hou

2009-01-01

353

Cascade-Correlation Neural Network Modeling of the Abrasive Flow Machining Process  

Microsoft Academic Search

This paper presents some preliminary work for modeling the abrasive flow machining (AFM) of automotive engine air intake manifolds using a cascade-correlation neural network approach. AFM has not been widely used because of the lack of theoretic support for the complex behavior of the process. Currently, this process can only be monitored subjectively by the plant engineers and is not

Sarah S. Y. Lam; Alice E. Smith

354

Artificial Neural Networks for detecting instability trends in different workpiece thicknesses in a machining process  

Microsoft Academic Search

This paper presents the use of artificial neural networks to diagnose degraded behaviours in wire electrical discharge machining (WEDM). The detection in advance of the degradation of the cutting process is crucial since this can lead to the breakage of the cutting tool (the wire), reducing the process productivity and the required accuracy. Concerning this, previous investigations have identified different

E. Portillo; M. Marcos; I. Cabanes; A. Zubizarreta; J. A. Sanchez

2008-01-01

355

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

Microsoft Academic Search

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

Josef Stráský; Miloš Jane?ek; Petr Harcuba; Michal Bukovina; Lothar Wagner

356

Micromanufacturing Of Hard To Machine Materials By Physical And Chemical Ablation Processes  

SciTech Connect

Miniaturization leads to high requirements to the applied manufacturing processes especially in respect to the used hard to machine materials and the aims of structure size and geometrical accuracy. Traditional manufacturing processes reach their limits here. One alternative for these provide thermal and chemical ablation processes. These processes are applied for the production of different microstructures in different materials like hardened steel, carbides and ceramics especially for medical engineering and tribological applications.

Schubert, A. [Fraunhofer Institute for Machine Tools and Forming Technology IWU, Chemnitz, 09126 (Germany); Chair Micromanufacturing Technology, Chemnitz University of Technology, Chemnitz, 09107 (Germany); Edelmann, J.; Gross, S.; Meichsner, G.; Wolf, N.; Schneider, J. [Fraunhofer Institute for Machine Tools and Forming Technology IWU, Chemnitz, 09126 (Germany); Zeidler, H.; Hackert, M. [Chair Micromanufacturing Technology, Chemnitz University of Technology, Chemnitz, 09107 (Germany)

2011-01-17

357

Product Model for Integrated Machining and Inspection Process Planning  

NASA Astrophysics Data System (ADS)

In the product-process development closed-loop an integrated product and process plan model is essential for structuring and interchanging data and information. Many of the currently existing standards (STEP) provide an appropriate solution for the different stages of the closed-loop using a clear feature-based approach. However, inspection planning is not undertaken in the same manner and detailed inspection (measurement) planning is performed directly. In order to carry out inspection planning, that is both integrated and at the same level as process planning, the Inspection Feature (InspF) is proposed here, which is directly related with product and process functionality. The proposal includes an InspF library that makes it possible part interpretation from an inspection point of view, while also providing alternatives and not being restricted to the use of just one single type of measurement equipment.

Gutiérrez Rubert, S.; Bruscas Bellido, G. M.; Rosado Castellano, P.; Romero Subirón, F.

2009-11-01

358

Modeling of spark erosion rate in microwire-EDM  

Microsoft Academic Search

Micro-wire electro-discharge machining (WEDM) has been identified as a micromachining process for the fabrication of components\\u000a of size down to the micrometer level. This process is derived from WEDM, and the principle of both the process is similar,\\u000a yet due to significant scaling down of the micro-WEDM process, lots of modifications in the circuit design, wire diameter,\\u000a stresses developed, and

Saradindu Das; Suhas S. Joshi

2010-01-01

359

The electron capture process in conventional annular machines  

Microsoft Academic Search

Experiments carried out on a 70-Mev synchrotron gave results in ; disagreement with the current injection philosophy: the yield is insensitive to ; the matching of the pulse front with the acceptance slope, and when two guns are ; used together their contributions never add to each other, but the more efficient ; gun takes over the process or disturbs

L. Gonella

1963-01-01

360

A note on single-machine scheduling with decreasing time-dependent job processing times  

Microsoft Academic Search

In this note we consider some single-machine scheduling problems with decreasing time-dependent job processing times. Decreasing time-dependent job processing times means that its processing time is a non-increasing function of its execution start time. We present polynomial solutions for the sum of squared completion times minimization problem, and the sum of earliness penalties minimization problem subject to no tardy jobs,

Ji-Bo Wang

2010-01-01

361

A digraph-based expert system for non-traditional machining processes selection  

Microsoft Academic Search

The presence of a number of available non-traditional machining (NTM) processes has brought out the idea of selecting the\\u000a most suitable NTM process for generating a desired shape feature on a given work material. This paper presents a digraph-based\\u000a approach to ease out the appropriate NTM process selection problem. It includes the design and development of an expert system\\u000a that

Nilanjan Das Chakladar; Ranatosh Das; Shankar Chakraborty

2009-01-01

362

Quantification of corrosion phenomena in plastic processing machines.  

PubMed

In a model platelet system the corrosion of metallic materials was studied by processing polyethylene, polyphenylene sulfide, and glass-fibre-reinforced polyphenylene sulfide. The measurement methods used were scanning electron microscopy (images), electron-probe microanalysis (lateral element maps), secondary-ion mass spectrometry (depth profiles), X-ray photoelectron spectroscopy (chemical bonding), and grazing-incidence X-ray diffraction (structures of crystalline compounds). As nondestructive measure of corrosive attack, grazing-incidence X-ray diffraction, using the intensity ratio (IFe-O/IFe), was found to be the method of choice. The reproducibility for the total procedure was found to range between 6 and 13% (rel.). The intensity ratio was examined as function of depth, of the time of stress, of material composition, and of the surrounding atmosphere. Oxides were identified as main corrosion products. The extent of oxide formation is proportional to the time elapsed after processing. PMID:11768480

Kemmler, B; Hoffmann, P; Cremer, M; Ortner, H M; Mennig, G

2001-11-01

363

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

364

A Monte Carlo Sequential Estimation of Point Process Optimum Filtering for Brain Machine Interfaces  

Microsoft Academic Search

The previous decoding algorithms for Brain Machine Interfaces are normally utilized to estimate animal's movement from binned spike rates, which loses spike timing resolution and may exclude rich neural dynamics due to single spikes. Based on recently proposed Monte Carlo sequential estimation algorithm on point process, we present a decoding framework to reconstruct the kinematic states directly from the multi-channel

Yiwen Wang; António R. C. Paiva; Jose C. Principe; Justin C. Sanchez

2007-01-01

365

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. Pöyhönen; M. Negrea; P. Jover; A. Arkkio; H. Hyötyniemi

2003-01-01

366

Minimizing the expected processing time on a flexible machine with random tool lives  

Microsoft Academic Search

We present a stochastic version of economic tool life models for machines with finite capacity tool magazines and a variable processing speed capability, where the tool life is a random variable. Using renewal theory to express the expected number of tool setups as a function of cutting speed and magazine capacity, we extend previously published deterministic mathematical programming models to

Bernard F. Lamond; Manbir S. Sodhi

2006-01-01

367

Single machine scheduling with exponential processing times and a general form objective function  

Microsoft Academic Search

A single machine scheduling with exponential processing times is considered, the objective is to minimize an objective function which is a general form of several regular (the objective function is increasing with respect to job completion times) and non-regular objective functions, such as, the expected flow time, the expected total tardiness about a deterministic common due date and the expected

Chunfu Jia

2003-01-01

368

Single machine scheduling with a variable common due date and resource-dependent processing times  

Microsoft Academic Search

The problem of scheduling n jobs with a variable common due date on a single machine is studied. It is assumed that the job processing times are non-increasing linear functions of an equal amount of a resource allocated to the jobs. The due date and resource values can be continuous or discrete. The objective is to minimize a linear combination

C. T. Daniel Ng; T. C. Edwin Cheng; Mikhail Y. Kovalyov; S. S. Lam

2003-01-01

369

A&M. TAN607. Process experimental pilot plant (PREPP) in north machine ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

A&M. TAN-607. Process experimental pilot plant (PREPP) in north machine shop of TAN-607. First floor plan shows kiln area, internal room dividers, air locks, and other features integrated within TAN-607. Ralph M. Parsons A-2. Date: February 1984. INEEL index no. 034-0607-00-693-147021 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

370

Electric energy forecasting in crude oil processing using Support Vector Machines and Particle Swarm Optimization  

Microsoft Academic Search

In this paper, support vector machines (SVMs) are applied in predicting fuel consumption in the first phase of oil refining at oil refinery ldquoNIS Rafinerija Nafte Novi Sadrdquo in Novi Sad, Serbia. During cross-validation process of the SVM training particle swarm optimization (PSO) algorithm was utilized in selection of free SVM parameters. In particular widths of radial basis functions, as

Milena Petrujkic; Milan R. Rapaic; Boris Jakovljevic; V. Dapic

2008-01-01

371

The Recognition of Cucumber Disease Based on Image Processing and Support Vector Machine  

Microsoft Academic Search

A new method of recognizing cucumber leaf disease based on computer image processing and Support Vector Machine (SVM) is studied to improve recognition accuracy and efficiency. At first, vector median filter was applied to remove noise of the acquired color images of cucumber disease leaf. Then a method of statistic pattern recognition and mathematics morphology was introduced to segment images

Tian Youwen; Li Tianlai; Niu Yan

2008-01-01

372

Solar activity detection and prediction using image processing and machine learning techniques  

Microsoft Academic Search

The objective of the research in this dissertation is to develop the methods for automatic detection and prediction of solar activities, including prominence eruptions, emerging flux regions and solar flares. Image processing and machine learning techniques are applied in this study. These methods can be used for automatic observation of solar activities and prediction of space weather that may have

Gang Fu

2007-01-01

373

The Relationship of Machine Learning and Data Compression to Natural Language Processing: A Review  

Microsoft Academic Search

We review the state of the art in natural language processing (NLP), machine learning, and data compression. Central to both the NLP and the compression problems is that of finding a language model, or probability distribution P over the set of strings in a human language such as English. As large text corpora become available, the traditional NLP approach of

Matt Mahoney

374

Machine vision feedback for on-line correction of manufacturing processes: a control formulation  

NASA Astrophysics Data System (ADS)

We study machine vision post-inspection of products for automatic correction of manufacturing processes. The general question is posed as a `discrete-event' stochastic control problem with the camera as the feedback sensor. The physical models employed yield insight into design procedures for robustness.

Taylor, Andrew T.; Wang, Paul K.

1991-12-01

375

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

376

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

377

XCUT: A rule-based expert system for the automated process planning of machined parts  

SciTech Connect

Automated process planning is becoming a popular research and development topic in engineering and applied artificial intelligence. It is generally defined as the automatic planning of the manufacturing procedures for producing a part from a CAD based product definition. An automated process planning system, XCUT, is currently being developed using rule-based expert system techniques. XCUT will generate process plans for the production of machined piece-parts, given a geometric description of a part's features. The system currently is focused on operation planning for prismatic parts on multi-axis CNC milling machines. To date, moderately complex 2-1/2D prismatic parts have successfully been planned for with approximately 300 rules in the knowledge base. This paper will describe the XCUT system, system architecture, knowledge representation, plan development sequence, and issues in applying expert system technology to automated process planning. 16 refs.

Brooks, S.L.; Hummel, K.E.; Wolf, M.L.

1987-06-01

378

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

379

Two-agent single-machine scheduling with position-dependent processing times  

Microsoft Academic Search

A new scheduling model in which both two-agent and position-dependent processing times exist simultaneously is considered\\u000a in this paper. Two agents compete to perform their respective jobs on a common single machine, and each agent has his own\\u000a criterion to optimize. The job position-dependent processing time is characterized by increasing or decreasing function dependent\\u000a on the position of a job

Peng Liu; Xiaoye Zhou; Lixin Tang

2010-01-01

380

Minimizing total tardiness on a single machine with controllable processing times  

Microsoft Academic Search

The concept of time-cost trade-off is commonly considered in PERT\\/CPM, but it is seldom considered in the scheduling area. Such concept implies that the processing times of jobs are controllable by increasing or decreasing the available resources, such as manpower and equipment. In this paper, we focus on the single machine total tardiness problem with controllable processing times. First, a

Chao-tang Tseng; Ching-jong Liao; Kuo-ling Huang

2009-01-01

381

Single-machine scheduling with precedence constraints and decreasing start-time dependent processing times  

Microsoft Academic Search

In this paper we consider single-machine scheduling problems with decreasing start-time-dependent processing times, i.e.,\\u000a jobs whose processing times are a decreasing function of their starting times. In addition, the jobs are related by parallel\\u000a chains and a series-parallel graph precedence constraint, respectively. It is shown that, for the problems of minimization\\u000a of the total weighted completion time, polynomial algorithms exist.

Wen-Jun Gao; Xue Huang; Ji-Bo Wang

2010-01-01

382

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

383

Neural network modeling and analysis of the material removal process during laser machining  

Microsoft Academic Search

To manufacture parts with nano- or micro-scale geometry using laser machining, it is essential to have a thorough understanding of the material removal process in order to control the system behaviour. At present, the operator must use trial-and-error methods to set the process control parameters related to the laser beam, motion system, and work piece material. In addition, dynamic characteristics

Basem F. Yousef; George K. Knopf; Evgueni V. Bordatchev; Suwas K. Nikumb

2003-01-01

384

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

385

Influence of electrical discharge machining on sliding friction and wear of WC–Ni cemented carbide  

Microsoft Academic Search

Tribological characteristics of fine-grained WC–8wt%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 WC–6wt%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

386

Electrical discharge machining of B 4C–TiB 2 composites  

Microsoft Academic Search

The interrelationships between the microstructure and electrical discharge machining (EDM) behaviour of B4C–TiB2 composites with respectively 30, 40 and 60vol.% TiB2 are investigated. Special attention was given to the influence of the grain size on the EDM behaviour by producing composites with an ultrafine TiB2 phase using in situ synthesis during PECS. The experimental work revealed that 40vol.% of TiB2

Olivier Malek; Jef Vleugels; Kim Vanmeensel; Shuigen Huang; Junhu Liu; Sven Van den Berghe; Amit Datye; Kuang-Hsi Wu; Bert Lauwers

2011-01-01

387

Abrasive micro-blasting to improve surface integrity of electrical discharge machined WC–Co composite  

Microsoft Academic Search

This study investigates the improvement of surface integrity of wire electrical discharge machined (EDM) WC–Co composite by abrasive micro-blasting. The thermally damaged recast layer generated by EDM has craters, cracks, and bubbles, which deteriorate the surface mechanical properties. The micro-blasting, using 6–12 and 4–20?m size SiC abrasive, enables the removal of the recast layer and is suitable for micro mechanical

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

2005-01-01

388

Wire electric discharge machining induced titanium hydride in Ti–46Al–2Cr alloy  

Microsoft Academic Search

Wire electric discharge machining (Wire-EDM) induced a new phase in Ti–46Al–2Cr (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 4.49–4.50 Å. 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

389

BRICORK: an automatic machine with image processing for the production of corks  

NASA Astrophysics Data System (ADS)

The production of cork stoppers from raw cork strip is a manual and labor-intensive process in which a punch-operator quickly inspects all sides of the cork strip for defects and decides where to punch out stoppers. He then positions the strip underneath a rotating tubular cutter and punches out the stoppers one at a time. This procedure is somewhat subjective and prone to error, being dependent on the judgement and accuracy of the operator. This paper describes the machine being developed jointly by Mecanova, Laboratorio Nacional de Engenharia e Tecnologia (LNETI) and Empresa de Investigacao e Desenvolvimento de Electronica SA (EID) which automatically processes cork strip introduced by an unskilled operator. The machine uses both image processing and laser inspection techniques to examine the strip. Defects in the cork are detected and categorized in order to determine regions where stoppers may be punched. The precise locations are then automatically optimized for best usage of the raw material (quantity and quality of stoppers). In order to achieve the required speed of production these image processing techniques may be implemented in hardware. The paper presents results obtained using the vision system software under development together with descriptions of both the image processing and mechanical aspects of the proposed machine.

Davies, Roger; Correia, Bento A.; Carvalho, Fernando D.; Rodrigues, Fernando C.

1991-06-01

390

A novel photochemical machining process for magnesium aerospace and biomedical microengineering applications  

NASA Astrophysics Data System (ADS)

Research was carried out to evaluate the feasibility of fabricating perforated (filigree) magnesium microcomponents with metal wire widths of the order of the metal thickness using a photochemical machining (PCM) process. Experimentally, it has been demonstrated for the first time that metal wire widths of 0.15 mm can be achieved within a 2D, 0.25 mm thick magnesium foil to fabricate microcomponents for use as micro air vehicle (MAV) wings or stents through a bespoke PCM process. This etching process differs significantly from the industrial etching process used currently to manufacture magnesium letterpress printing plates and embossing dies.

Allen, D. M.; Simpkins, M.; Almond, H.

2010-10-01

391

The status of the Storage Ring EDM experiment  

SciTech Connect

The status of the storage ring experiment capable of probing the proton and deuteron EDM at the 10{sup -29} e.cm level is presented here. At this level it will be sensitive to a new physics mass scale of {approx}300 TeV. If there is new physics at the LHC, it will be sensitive to 10{mu}rad CP-violating phase level making it the most sensitive experiment for CP-violation beyond the SM.

Semertzidis, Yannis K. [Brookhaven National Laboratory (United States)

2009-12-17

392

A multi-agent-based negotiation approach for parallel machine scheduling with multi-objectives in an electroetching process  

Microsoft Academic Search

Electro-etching is a critical process in producing aluminium foil, and it always involves many parallel machines with three distinct voltages. Therefore, production scheduling involves these parallel machines and their eligibility. In this paper, an agent-based negotiation approach is proposed to develop a distributed parallel machine scheduling application in this manufacturing environment. The agent-based system consists of types of agent, i.e.

Ching-Jen Huang; Li-Man Liao

2011-01-01

393

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

394

Achieving precision in high density batch mode micro-electro-discharge machining  

NASA Astrophysics Data System (ADS)

This paper reports a parametric study of batch mode micro-electro-discharge machiningEDM) of high density features in stainless steel. Lithographically fabricated copper tools with single cross, parallel line and 8 × 8 circle/square array features of 5-100 µm width and 5-75 µm spacing were used to quantify trends in machining tolerance and the impact of debris accumulation. As the tool feature density is increased, debris accumulation effects begin to dominate, eventually degrading both tool and workpiece. Two independent techniques for mitigating this debris buildup are separately investigated. The first is a passivation coating which suppresses spurious discharges triggered from the sidewalls of the machining tool. By this method, the mean tool wear rate decreases from a typical of about 34% to 1.7% and machining non-uniformity reduces from 4.9 µm to 1.1 µm across the workpiece. The second technique involves a two-step machining process that enhances the hydrodynamic removal of machining debris compared to standard methods. This improves surface and edge finish, machining time and tool wear.

Richardson, Mark T.; Gianchandani, Yogesh B.

2008-01-01

395

A search engine for the engineering and equipment data management system (EDMS) at CERN  

NASA Astrophysics Data System (ADS)

CERN, the European Laboratory for Particle Physics, located in Geneva -Switzerland, is currently building the LHC (Large Hadron Collider), a 27 km particle accelerator. The equipment life-cycle management of this project is provided by the Engineering and Equipment Data Management System (EDMS [1] [2]) Service. Using an Oracle database, it supports the management and follow-up of different kinds of documentation through the whole life cycle of the LHC project: design, manufacturing, installation, commissioning data etc... The equipment data collection phase is now slowing down and the project is getting closer to the 'As-Built' phase: the phase of the project consuming and exploring the large volumes of data stored since 1996. Searching through millions of items of information (documents, equipment parts, operations...) multiplied by dozens of points of view (operators, maintainers...) requires an efficient and flexible search engine. This paper describes the process followed by the team to implement the search engine for the LHC As-built project in the EDMS Service. The emphasis is put on the design decision to decouple the search engine from any user interface, potentially enabling other systems to also use it. Projections, algorithms, and the planned implementation are described in this paper. The implementation of the first version started in early 2007.

Tsyganov, A.; Amérigo, S. M.; Petit, S.; Pettersson, T.; Suwalska, A.

2008-07-01

396

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

397

A confidence voting process for ranking problems based on support vector machines  

Microsoft Academic Search

Abstract In this paper, we deal with ranking problems arising from various data mining applications where the major task is to train a rank-prediction model to assign every instance a rank. We flrst discuss the merits and potential disadvantages of two existing popular approaches for ranking problems: the ‘Max-Wins’ voting process based on multi-class support vector machines (SVMs) and the

Tianshi Jiao; Jiming Peng; Tamás Terlaky

2009-01-01

398

Modeling of TIG welding and abrasive flow machining processes using radial basis function networks  

Microsoft Academic Search

Input-output relationships of tungsten inert gas (TIG) welding and abrasive flow machining (AFM) processes were determined\\u000a using radial basis function networks (RBFNs). A batch mode of training was adopted to implement the principle of back-propagation\\u000a (BP) algorithm (which works based on a steepest descent algorithm) and a genetic algorithm (GA), separately. The performances\\u000a of RBFN tuned by a BP algorithm

Asfak Ali Mollah; Dilip Kumar Pratihar

2008-01-01

399

Modeling and multi-response optimization of Inconel 718 on machining of CNC WEDM process  

Microsoft Academic Search

This paper describes the development of artificial neural network (ANN) models and multi-response optimization technique to predict and select the best cutting parameters of wire electro-discharge machining (WEDM) process. To predict the performance characteristics namely material removal rate and surface roughness, artificial neural network models were developed using back-propagation algorithms. Inconel 718 was selected as work material to conduct experiments.

R. Ramakrishnan; L. Karunamoorthy

2008-01-01

400

Development of an management information system as knowledge base model for machining process characterisation  

Microsoft Academic Search

The current paper intends to use the typical problems of parameter selection and optimization in machining processes to bring\\u000a out the design ideas that form the foundation of n-tier management information systems (MIS). These ideas can be used for\\u000a creating data-driven, scalable enterprise information systems. The current phase (phase I) of the implementation highlights\\u000a the capabilities of these design ideas

S. Chakrabarti; S. Mitra; B. Bhattacharyya

2007-01-01

401

A study on surface roughness in abrasive waterjet machining process using artificial neural networks and regression analysis method  

Microsoft Academic Search

In the present study, artificial neural network (ANN) and regression model were developed to predict surface roughness in abrasive waterjet machining (AWJ) process. In the development of predictive models, machining parameters of traverse speed, waterjet pressure, standoff distance, abrasive grit size and abrasive flow rate were considered as model variables. For this purpose, Taguchi's design of experiments was carried out

Ula? Çayda?; Ahmet Hasçal?k

2008-01-01

402

Electrical discharge machining of titanium alloy (Ti 6Al 4V)  

NASA Astrophysics Data System (ADS)

In this study, the electrical discharge machining (EDM) of titanium alloy (Ti 6Al 4V) with different electrode materials namely, graphite, electrolytic copper and aluminium and process parameters such as, pulse current and pulse duration were performed to explore the influence of EDM parameters on various aspects of the surface integrity of Ti6Al4V. Scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectrograph (EDS) and hardness analysis were performed. The experimental results reveal that the value of material removal rate, surface roughness, electrode wear and average white layer thickness are tendency of increase with increasing current density and pulse duration. However, extremely long-pulse durations such as 200 ?s led to decrease MRR and surface roughness. Furthermore, the surface hardness is increasing due to the Ti24C15 carbides formed on the surface and obvious cracks are always evident in re-solidified layer when machining copper electrode. The surface crack densities and critical crack lines were determined for the tested material. The graphite electrode is beneficial on material removal rate, electrode wear and surface crack density but relatively poorer surface finish.

Hasçal?k, Ahmet; Çayda?, Ula?

2007-09-01

403

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, Dan; Geier, Dan P.; Lang, Dennis D.

1996-11-01

404

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

405

The new technology of the materials process: microvia formation by CO2 laser drilling machine  

NASA Astrophysics Data System (ADS)

The purpose of this paper is the microvia results of different materials (RCC, FR4 and Cu) using CO2 laser drilling machine at the wavelength of 10600 nm. We investigated the mechanism of this process with CO2 laser and the microvia results of different materials. The microvia with a diameter up to 150 microns through laser drilling are presented. In this paper we report the results of a dielectric material such as the RCC and FR4 which used the different parameter of laser. In addition, the high power required for drilling copper foil compared to the resin material is due to the low absorption and high reflection of copper around 10600 nm wavelengths. We will present the method of the copper drilling based on a CO2 laser drilling machine system which used the low power.

Chen, Ming-Fei; Chen, Yu-Pin

2005-04-01

406

Limitations Of The Current State Space Modelling Approach In Multistage Machining Processes Due To Operation Variations  

NASA Astrophysics Data System (ADS)

The State Space modelling approach has been recently proposed as an engineering-driven technique for part quality prediction in Multistage Machining Processes (MMP). Current State Space models incorporate fixture and datum variations in the multi-stage variation propagation, without explicitly considering common operation variations such as machine-tool thermal distortions, cutting-tool wear, cutting-tool deflections, etc. This paper shows the limitations of the current State Space model through an experimental case study where the effect of the spindle thermal expansion, cutting-tool flank wear and locator errors are introduced. The paper also discusses the extension of the current State Space model to include operation variations and its potential benefits.

Abellán-Nebot, J. V.; Liu, J.; Romero, F.

2009-11-01

407

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

408

{sup 3}He MAGNETOMETRY FOR A NEUTRON EDM MEASUREMENT  

SciTech Connect

The behavior of small amounts of polarized {sup 3}He in a bath of superfluid {sup 4}He at temperatures below 1 K is critical to a new technique for measuring the EDM of the neutron. We report on studies to enhance the number of ultracold neutrons produced in such a bath, on the development of neutron tomography in gaseous mixtures, on magnet properties associated with the precession of {sup 3}He, and on preparations for tests of the distribution and diffusion coefficients of {sup 3}He in the bath.

P. BANGERT; ET AL

2000-08-01

409

Some single-machine scheduling problems with the extended sum-of-processing-time-based aging effect  

Microsoft Academic Search

In this paper, we analyze some single machine scheduling problems with the aging effect. We extend the sum-of-processing-time-based\\u000a aging model such that the fatigue caused by each job to the machine is equal to a non-increasing function dependent on the\\u000a normal processing time of a job and the aging effect is job dependent. Although the proposed model is more general

Rados?aw Rudek

410

Optimization strategy in end milling process for high speed machining of hardened die\\/mold steel  

Microsoft Academic Search

An optimization strategy for high speed machining of hardened die\\/mold steel based on machining feature analysis was studied. It is a further extension of the previously presented study on the thermal mechanism of end milling and constant cutting force control. An objective function concerning machining cost and associated optimization algorithm based on machining time and cutting length calculation was proposed.

Ying Tang

2006-01-01

411

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

412

Determination of reservoir induced earthquake using support vector machine and gaussian process regression  

NASA Astrophysics Data System (ADS)

The prediction of magnitude (M) of reservoir induced earthquake is an important task in earthquake engineering. In this article, we employ a Support Vector Machine (SVM) and Gaussian Process Regression (GPR) for prediction of reservoir induced earthquake M based on reservoir parameters. Comprehensive parameter (E) and maximum reservoir depth (H) are considered as inputs to the SVM and GPR. We give an equation for determination of reservoir induced earthquake M. The developed SVM and GPR have been compared with the Artificial Neural Network (ANN) method. The results show that the developed SVM and GPR are efficient tools for prediction of reservoir induced earthquake M.

Samui, Pijush; Kim, Dookie

2013-06-01

413

Cooperative optimization of reconfigurable machine tool configurations and production process plan  

NASA Astrophysics Data System (ADS)

The production process plan design and configurations of reconfigurable machine tool (RMT) interact with each other. Reasonable process plans with suitable configurations of RMT help to improve product quality and reduce production cost. Therefore, a cooperative strategy is needed to concurrently solve the above issue. In this paper, the cooperative optimization model for RMT configurations and production process plan is presented. Its objectives take into account both impacts of process and configuration. Moreover, a novel genetic algorithm is also developed to provide optimal or near-optimal solutions: firstly, its chromosome is redesigned which is composed of three parts, operations, process plan and configurations of RMTs, respectively; secondly, its new selection, crossover and mutation operators are also developed to deal with the process constraints from operation processes (OP) graph, otherwise these operators could generate illegal solutions violating the limits; eventually the optimal configurations for RMT under optimal process plan design can be obtained. At last, a manufacturing line case is applied which is composed of three RMTs. It is shown from the case that the optimal process plan and configurations of RMT are concurrently obtained, and the production cost decreases 6.28% and nonmonetary performance increases 22%. The proposed method can figure out both RMT configurations and production process, improve production capacity, functions and equipment utilization for RMT.

Xie, Nan; Li, Aiping; Xue, Wei

2012-09-01

414

Fast Parallel Computing Machine for Real Time Decision Making: Applications to Real Time Processing, War Games, Forest Fire and Fluid Dynamics Models.  

National Technical Information Service (NTIS)

The hardware prototype of a MIMD (multiple instruction multiple data) computing machine dedicated to the processing of large amounts of data in real time is described. The Lattice Automata Machine (LAM) is based on cellular automata architecture, but has ...

J. Toste-rego R. Dilao

1995-01-01

415

Machine Learning.  

ERIC Educational Resources Information Center

|As scientists seek to develop machines that can "learn," that is, solve problems by imitating the human brain, a gold mine of information on the processes of human learning is being discovered, expert systems are being improved, and human-machine interactions are being enhanced. (SK)|

Kirrane, Diane E.

1990-01-01

416

Discrete Optimization Optimal allocation and processing time decisions on non-identical parallel CNC machines: ? -constraint approach  

Microsoft Academic Search

When the processing times of jobs are controllable, selected processing times affect both the manufacturing cost and the scheduling performance. A well known example for such a case that this paper specifically deals with is the turning oper- ation on a CNC machine. Manufacturing cost of a turning operation is a nonlinear convex function of its processing time. In this

Sinan Gurel; M. Selim Akturk

417

Performance evaluation and rheological characterization of newly developed butyl rubber based media for abrasive flow machining process  

Microsoft Academic Search

The precision manufacturing technology always demands a good surface finish at low cost. This scenario drives both industries and research community to develop novel finishing processes. Presently, there are many techniques and one among them is abrasive flow machining (AFM) process. The media developed by optimum process variables mainly governs the performance of AFM. In the present experimental endeavor, an

Kamal K. Kar; N. L. Ravikumar; Piyushkumar B. Tailor; J. Ramkumar; D. Sathiyamoorthy

2009-01-01

418

Prediction and analysis of radial overcut in holes drilled by electrochemical machining process  

NASA Astrophysics Data System (ADS)

Radial overcut predictive models using multiple regression analysis, artificial neural network and co-active neurofuzzy inference system are developed to predict the radial overcut during electrochemical drilling with vacuum extraction of electrolyte. Four process parameters, electrolyte concentration, voltage, initial machining gap and tool feed rate, are selected to develop the models. The comparison between the results of the presented models shows that the artificial neural network and co-active neuro-fuzzy inference system models can predict the radial overcut with an average relative error of nearly 5%. Main effect and interaction plots are generated to study the effects of process parameters on the radial overcut. The analysis shows that the voltage, electrolyte concentration and tool feed rate have significant effect on radial overcut, respectively, while initial machining gap has a little effect. It is also found that the increase of the voltage and electrolyte concentration increases the radial overcut and the increase of the tool feed rate decreases the radial overcut.

Tajdari, Mehdi; Chavoshi, Saeed Zare

2013-09-01

419

Machine and Process System Diagnostics Using One-Step Prediction Maps  

SciTech Connect

This paper describes a method for machine or process system diagnostics that uses one-step prediction maps. The method uses nonlinear time series analysis techniques to form a one-step prediction map that estimates the next time series data point when given a sequence of previously measured time series data point. The difference between the predicted and measured time series values is a measure of the map error. The average value of this error should remain within some bound as long as both the dynamic system and its operating condition remain unchanged. However, changes in the dynamic system or operating condition will cause an increase in average map error. Thus, for a constant operating condition, monitoring the average map error over time should indicate when a change has occurred in the dynamic system. Furthermore, the map error itself forms a time series that can be analyzed to detect changes in system dynamics. The paper provides technical background in the nonlinear analysis techniques used in the diagnostic method, describes the creation of one-step prediction maps and their application to machine or process system diagnostics, and then presents results obtained from applying the diagnostic method to simulated and measured data.

Breeding, J.E.; Damiano, B.; Tucker, R.W., Jr.

1999-05-10

420

Prediction and analysis of radial overcut in holes drilled by electrochemical machining process  

NASA Astrophysics Data System (ADS)

Radial overcut predictive models using multiple regression analysis, artificial neural network and co-active neurofuzzy inference system are developed to predict the radial overcut during electrochemical drilling with vacuum extraction of electrolyte. Four process parameters, electrolyte concentration, voltage, initial machining gap and tool feed rate, are selected to develop the models. The comparison between the results of the presented models shows that the artificial neural network and co-active neuro-fuzzy inference system models can predict the radial overcut with an average relative error of nearly 5%. Main effect and interaction plots are generated to study the effects of process parameters on the radial overcut. The analysis shows that the voltage, electrolyte concentration and tool feed rate have significant effect on radial overcut, respectively, while initial machining gap has a little effect. It is also found that the increase of the voltage and electrolyte concentration increases the radial overcut and the increase of the tool feed rate decreases the radial overcut.

Tajdari, Mehdi; Chavoshi, Saeed Zare

2013-05-01

421

The effect of heterogeneous second phase on the machinability evaluation of spheroidal graphite cast irons in the WEDM process  

Microsoft Academic Search

This paper presents an investigation about the relationships between the heterogeneous second phase and the machinability evaluation of the ferritic SG cast irons in the wire electric discharge machining (WEDM) process. The factors of second phase considered are the quantity, diameter and area fraction of spheroidal graphite particles. The experimental specimens adopted a range of 2.1–4.1mass% to change the carbon

Te-Chang Tsai; Jenn-Tsong Horng; Nun-Ming Liu; Chih-Chung Chou; Ko-Ta Chiang

2008-01-01

422

Characterization of a hybrid laser-assisted mechanical micromachining (LAMM) process for a difficult-to-machine material  

Microsoft Academic Search

Mechanical micro-cutting is emerging as a viable alternative to lithography based micromachining techniques for applications in optics, semiconductors and micro-mold\\/dies. However, certain factors limit the types of workpiece materials that can be processed using mechanical micromachining methods. For difficult-to-machine materials such as mold and die steels or ceramics, limited cutting tool\\/machine stiffness and strength are major impediments to the efficient

Ramesh Singh; Shreyes N. Melkote

2007-01-01

423

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

424

Computer-based diagnostic monitoring to enhance the human-machine interface of complex processes  

SciTech Connect

There is a growing interest in introducing an automated, on-line, diagnostic monitoring function into the human-machine interfaces (HMIs) or control rooms of complex process plants. The design of such a system should be properly integrated with other HMI systems in the control room, such as the alarms system or the Safety Parameter Display System (SPDS). This paper provides a conceptual foundation for the development of a Plant-wide Diagnostic Monitoring System (PDMS), along with functional requirements for the system and other advanced HMI systems. Insights are presented into the design of an efficient and robust PDMS, which were gained from a critical review of various methodologies developed in the nuclear power industry, the chemical process industry, and the space technological community.

Kim, I.S.

1992-02-01

425

Manufacture of Overhanging Sharp Corner by Means of 6Axis Control Machining with the Application of Ultrasonic Vibrations  

Microsoft Academic Search

The study proposes a new machining method to create an overhanging sharp corner. Sharp corners on overhanging surfaces are difficult to machine in conventional way or even in 3 to 5-axis EDM especially if the surfaces have different angles. This is due to the limitation of the feed direction and the structure of the electrode wherein it must be symmetrical

Feliciano H. Japitana; Koichi Morishige; Shugo Yasuda; Yoshimi Takeuchi

2003-01-01

426

RESIDUAL STRESS STATE IN ELECTRICAL DISCHARGE MACHINED SURFACE OF PLASTIC MOLD STEEL WITH DE-IONIZED WATER AS DIELECTRIC FLUID  

Microsoft Academic Search

This paper presents procedures and results of experimental studies to measure residual stresses in electric discharge machined surfaces. Layer removal method is used to measure the residual stress profile in function of depth beneath surface caused by die sinking type EDM. In this method, tiny stressed layers are removed from machined samples by electrochemical polishing and corresponding deformations due to

B. Ekmekçi; O. Elkoca; A. E. Tekkaya; A. Erden

427

Preliminary design and manufacturing feasibility study for a machined Zircaloy triangular pitch fuel rod support system (grids) (AWBA development program)  

Microsoft Academic Search

General design features and manufacturing operations for a high precision machined Zircaloy fuel rod support grid intended for use in advanced light water prebreeder or breeder reactor designs are described. The grid system consists of a Zircaloy main body with fuel rod and guide tube cells machined using wire EDM, a separate AM-350 stainless steel insert spring which fits into

Horwood

1981-01-01

428

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

429

Integrated process planning and scheduling in holonic manufacturing systems-optimization based on shop time and machining cost  

Microsoft Academic Search

The objective of the present research is to develop an integrated process planning and scheduling system of machine products, aiming at realizing a flexible production control in holonic manufacturing systems. Basic architecture of the target holonic manufacturing system is discussed from the viewpoint of the integration of the process planning and the scheduling systems. Procedures are proposed to select suitable

N. Sugimura; R. Shrestha; J. Inoue

2003-01-01

430

The Feasibility Analysis of Electrical-Discharge Machining of Carbon-Carbon Composites  

Microsoft Academic Search

The objective of this research is to investigate the feasibility of using Electrical-Discharge Machining (EDM) for carbon-carbon composite materials as well as the effects of major machining parameters. The material was machined by electrical-discharge sinker using copper electrode. The mechanism of material removal has been revealed by the morphology of debris. The material removal rate, the surface topography and the

H. Hocheng; Y. H. Guu; N. H. Tai

1998-01-01

431

Image processing with genetic algorithm in a raisin sorting system based on machine vision  

NASA Astrophysics Data System (ADS)

This study was undertaken to develop machine vision-based raisin detection technology. Supervised color image segmentation using a Permutation-coded Genetic Algorithm (GA) identifying regions in Hue-Saturation-Intensity (HSI) color space (GAHSI) for desired and undesired raisin detection was successfully implemented. Images were captured to explore the possibility of using GAHSI to locate desired raisin and undesired raisin regions in color space simultaneously. In this research, images were processed separately using three segmentation method, K-Means clustering in L*a*b* color space and GAHSI for single image, GA for single image in Red-Green-Blue (RGB) color space (GARGB). The GAHSI results provided evidence for the existence and separability of such regions. When compared with cluster analysis-based segmentation results, the GAHSI method showed no significant difference.

Abbasgholipour, Mahdi; Alasti, Behzad Mohammadi; Abbasgholipour, Vahdi; Derakhshan, Ali; Abbasgholipour, Mohammad; Rahmatfam, Sharmin; Rahmatfam, Sheyda; Habibifar, Rahim

2012-04-01

432

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

433

Single-machine scheduling with a sum-of-processing-time based learning effect and deteriorating jobs  

Microsoft Academic Search

The paper deals with the single-machine scheduling problem with a sum-of-processing-time- based learning effect and deteriorating\\u000a jobs. By the effects of sum-of-processing-time-based learning and deterioration, we mean that the processing time of a job\\u000a is defined by function of its starting time and total normal processing time of jobs in front of it in the sequence. It is\\u000a shown that,

Li-Yan Wang; Ji-Bo Wang; Dan Wang; Na Yin; Xue Huang; En-Min Feng

2009-01-01

434

Do Two Machine-Learning Based Prognostic Signatures for Breast Cancer Capture the Same Biological Processes?  

PubMed Central

The fact that there is very little if any overlap between the genes of different prognostic signatures for early-discovery breast cancer is well documented. The reasons for this apparent discrepancy have been explained by the limits of simple machine-learning identification and ranking techniques, and the biological relevance and meaning of the prognostic gene lists was questioned. Subsequently, proponents of the prognostic gene lists claimed that different lists do capture similar underlying biological processes and pathways. The present study places under scrutiny the validity of this claim, for two important gene lists that are at the focus of current large-scale validation efforts. We performed careful enrichment analysis, controlling the effects of multiple testing in a manner which takes into account the nested dependent structure of gene ontologies. In contradiction to several previous publications, we find that the only biological process or pathway for which statistically significant concordance can be claimed is cell proliferation, a process whose relevance and prognostic value was well known long before gene expression profiling. We found that the claims reported by others, of wider concordance between the biological processes captured by the two prognostic signatures studied, were found either to be lacking statistical rigor or were in fact based on addressing some other question.

Drier, Yotam; Domany, Eytan

2011-01-01

435

Comparison of support vector machine-based processing chains for hyperspectral image classification  

NASA Astrophysics Data System (ADS)

Many different approaches have been proposed in recent years for remotely sensed hyperspectral image classification. Despite the variety of techniques designed to tackle the aforementioned problem, the definition of standardized processing chains for hyperspectral image classification is a difficult objective, which may ultimately depend on the application being addressed. Generally speaking, a hyperspectral image classification chain may be defined from two perspectives: 1) the provider's viewpoint, and 2) the user's viewpoint, where the first part of the chain comprises activities such as data calibration and geo-correction aspects, while the second part of the chain comprises information extraction processes from the collected data. The modules in the second part of the chain (which constitutes our main focus in this paper) should be ideally flexible enough to be accommodated not only to different application scenarios, but also to different hyperspectral imaging instruments with varying characteristics, and spatial and spectral resolutions. In this paper, we evaluate the performance of different processing chains resulting from combinations of modules for dimensionality reduction, feature extraction/ selection, image classification, and spatial post-processing. The support vector machine (SVM) classifier is adopted as a baseline due to its ability to classify hyperspectral data sets using limited training samples. A specific classification scenario is investigated, using a reference hyperspectral data set collected by NASA's Airborne Visible Infra-Red Imaging Spectrometer (AVIRIS) over the Indian Pines region in Indiana, USA.

Rojas, Marta; Dópido, Inmaculada; Plaza, Antonio; Gamba, Paolo

2010-08-01

436

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

437

Electron EDM searches based on alkali-metal- or alkaline-earth-metal-bearing molecules  

NASA Astrophysics Data System (ADS)

We introduce four new molecules - YbRb, YbCs, YbSr^+, and YbBa^+ - that may prove fruitful in experimental searches for the electric-dipole moment (EDM) of the electron. These molecules can, in principle, be prepared at extremely low temperatures by photoassociating ultracold atoms and therefore may present an advantage over molecular-beam experiments. Here we discuss properties of these molecules and assess the effective electric fields they contribute to an electron EDM measurement.

Meyer, Edmund; Bohn, John

2010-03-01

438

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\\u000a importance. Rough cutting operation in WEDM is treated as a challenging one because improvement of more than one machining\\u000a performance measures viz. metal removal rate (MRR), surface finish (SF) and cutting width (kerf) are sought to obtain a precision\\u000a work. Using Taguchi’s

S. S. Mahapatra; Amar Patnaik

2007-01-01

439

Allosteric regulation of E2:E3 interactions promote a processive ubiquitination machine.  

PubMed

RING finger proteins constitute the large majority of ubiquitin ligases (E3s) and function by interacting with ubiquitin-conjugating enzymes (E2s) charged with ubiquitin. How low-affinity RING-E2 interactions result in highly processive substrate ubiquitination is largely unknown. The RING E3, gp78, represents an excellent model to study this process. gp78 includes a high-affinity secondary binding region for its cognate E2, Ube2g2, the G2BR. The G2BR allosterically enhances RING:Ube2g2 binding and ubiquitination. Structural analysis of the RING:Ube2g2:G2BR complex reveals that a G2BR-induced conformational effect at the RING:Ube2g2 interface is necessary for enhanced binding of RING to Ube2g2 or Ube2g2 conjugated to Ub. This conformational effect and a key ternary interaction with conjugated ubiquitin are required for ubiquitin transfer. Moreover, RING:Ube2g2 binding induces a second allosteric effect, disrupting Ube2g2:G2BR contacts, decreasing affinity and facilitating E2 exchange. Thus, gp78 is a ubiquitination machine where multiple E2-binding sites coordinately facilitate processive ubiquitination. PMID:23942235

Das, Ranabir; Liang, Yu-He; Mariano, Jennifer; Li, Jess; Huang, Tao; King, Aaren; Tarasov, Sergey G; Weissman, Allan M; Ji, Xinhua; Byrd, R Andrew

2013-08-13

440

A unified analysis for the single-machine scheduling problem with controllable and non-controllable variable job processing times  

Microsoft Academic Search

We present a unified analysis for single-machine scheduling problems in which the actual job processing times are controlled by either a linear or a convex resource allocation function and also vary concurrently depending on either the job’s position in the sequence and\\/or on the total processing time of the already processed jobs. We show that the problem is solvable in

Christos Koulamas; Sushil Gupta; George J. Kyparisis

2010-01-01

441

Solar activity detection and prediction using image processing and machine learning techniques  

NASA Astrophysics Data System (ADS)

The objective of the research in this dissertation is to develop the methods for automatic detection and prediction of solar activities, including prominence eruptions, emerging flux regions and solar flares. Image processing and machine learning techniques are applied in this study. These methods can be used for automatic observation of solar activities and prediction of space weather that may have great influence on the near earth environment. The research presented in this dissertation covers the following topics: (i) automatic detection of prominence eruptions (PEs), (ii) automatic detection of emerging flux regions (EFRs), and (iii) automatic prediction of solar flares. In detection of prominence eruptions, an automated method is developed by combining image processing and pattern recognition techniques. Consecutive Ha solar images are used as the input. The image processing techniques, including image transformation, segmentation and morphological operations are used to extract the limb objects and measure the associated properties. The pattern recognition techniques, such as Support Vector Machine (SVM), are applied to classify all the objects and generate a list of identified the PEs as the output. In detection of emerging flux regions, an automatic detection method is developed by using multi-scale circular harmonic filters. Kalman filter and SVM. The method takes a sequence of consecutive Michelson Doppler Imager (MDI) magnetograms as the input. The multi-scale circular harmonic filters are applied to detect bipolar regions from the solar disk surface and these regions are traced by Kalman filter until their disappearance. Finally, a SVM classifier is applied to distinguish EFRs from the other regions based on statistical properties. In solar flare prediction, it is modeled as a conditional density estimation (CDE) problem. A novel method is proposed to solve the CDE problem using kernel-based nonlinear regression and moment-based density function reconstruction techniques. This method involves two main steps. In the first step, kernel-based nonlinear regression techniques are applied to predict the conditional moments of the target variable, such as flare peak intensity or flare index. In the second step, the condition density function is reconstructed based on the estimated moments. The method is compared with the traditional double-kernel density estimator, and the experimental results show that it yields the comparable performance of the double-kernel density estimator. The most important merit of this new method is that it can handle high dimensional data effectively, while the double-kernel density estimator has confined to the bivariate case due to the difficulty of determining optimal bandwidths. The method can be used to predict the conditional density function of either flare peak intensity or flare index, which shows that our method is of practical significance in automated flare forecasting.

Fu, Gang

2007-07-01

442

Intelligent machines in the 21st century: automating the processes of inference and inquiry  

Microsoft Academic Search

The last century saw the application of Boolean algebra toward the construction of computing machines, which work by applying logical transformations to infor- mation contained in their memory. The development of information theory and the generalization of Boolean algebra to Bayesian inference have enabled these comput- ing machines, in the last quarter of the twentieth century, to be endowed with

Kevin H. Knuth

443

Minimizing weighted earliness and tardiness penalties about a common due date on single machine with exponential processing times  

Microsoft Academic Search

A problem of scheduling n jobs with exponential processing times on a single machine is discussed, the objective is to find an optimal schedule to minimize the expectation of total weighted absolute deviations of completion times about a deterministic common due date. This problem is a typical scheduling model in just-in-time manufacturing system where both earliness penalties and tardiness penalties

Chunfu Jia

2004-01-01

444

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

445

Application of system engineering processes to analyze and predict engine cooling fan system noise for off-highway machines  

Microsoft Academic Search

System Engineering processes were applied to create a Cooling Fan System Noise Analysis Tool for a back-hoe loader machine. The Cooling Fan System Noise Analysis Tool combined elements of aeroacoustic theory, Fan Law, sound power measurements and particle image velocimetry into a single computer analysis tool. The cooling fan system consisted of a cooling fan, multiple radiators in front of

Christopher P. Masini; J. Adin Mann

2005-01-01

446

Fabrication Process for Machined and Shrink-Fitted Impactor-Type Liners for the LOS Alamos Hedp Program  

NASA Astrophysics Data System (ADS)

Composite liners have been fabricated for the Los Alamos liner-driven High Energy Density Physics (HEDP) experiments using impactors formed by physical vapor deposition, and by machining and shrink fitting. Chemical vapor deposition has been proposed for some ATLAS liner applications. This paper describes the processes used to fabricate machined and shrink-fitted impactors; these processes have been used for copper impactors in 1100 aluminum liners and for 6061 T-6 aluminum impactors in 1100 aluminum liners. The most successful processes have been largely empirically developed and rely upon a combination of shrink-fitting and light press fitting. The processes used to date will be described along with some considerations for future composite liners for the HEDP Program.

Randolph, B.

2004-11-01

447

Predictions on surface finish in electrical discharge machining based upon neural network models  

Microsoft Academic Search

Predictions on the surface finish of work-pieces in electrical discharge machining (EDM) based upon physical or empirical models have been reported in the past years. However, when the change of electrode polarity has been considered, very few models have given reliable predictions. In this study, the comparisons on predictions of surface finish for various work materials with the change of

Kuo-Ming Tsai; Pei-Jen Wang

2001-01-01

448

Wear mechanism of metal bond diamond wheels trued by wire electrical discharge machining  

Microsoft Academic Search

The stereographic scanning electron microscopy (SEM) imaging was used to investigate the wear mechanism in wire electrical discharge machining (EDM) truing of metal bond diamond wheels for ceramic grinding. A piece of the grinding wheel was removed after truing and grinding to enable the examination of wheel surface and measurement of diamond protrusion heights using a SEM and stereographic imaging

Brian K. Rhoney; Albert J. Shih; Ronald O. Scattergood; Ronald Ott; Samuel B. McSpaddenc

2002-01-01

449

Time and spatially-resolved characterization of electrical discharge machining plasma  

Microsoft Academic Search

Plasma created during electrical discharge machining (EDM) is investigated with fast imaging and with time- and spatially-resolved optical emission spectroscopy. After the breakdown, the plasma develops very fast (<50 ns) and then remains stable. The plasma excites a broad volume around the electrode gap. Light is still emitted after the discharge by incandescent liquid metallic particles coming from the erosion

A. Descoeudres; Ch Hollenstein; G. Wälder; R. Demellayer; R. Perez

2008-01-01

450

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

451

Decoding semi-constrained brain activity from FMRI using support vector machines and gaussian processes.  

PubMed

Predicting a particular cognitive state from a specific pattern of fMRI voxel values is still a methodological challenge. Decoding brain activity is usually performed in highly controlled experimental paradigms characterized by a series of distinct states induced by a temporally constrained experimental design. In more realistic conditions, the number, sequence and duration of mental states are unpredictably generated by the individual, resulting in complex and imbalanced fMRI data sets. This study tests the classification of brain activity, acquired on 16 volunteers using fMRI, during mental imagery, a condition in which the number and duration of mental events were not externally imposed but self-generated. To deal with these issues, two classification techniques were considered (Support Vector Machines, SVM, and Gaussian Processes, GP), as well as different feature extraction methods (General Linear Model, GLM and SVM). These techniques were combined in order to identify the procedures leading to the highest accuracy measures. Our results showed that 12 data sets out of 16 could be significantly modeled by either SVM or GP. Model accuracies tended to be related to the degree of imbalance between classes and to task performance of the volunteers. We also conclude that the GP technique tends to be more robust than SVM to model unbalanced data sets. PMID:22563410

Schrouff, Jessica; Kussé, Caroline; Wehenkel, Louis; Maquet, Pierre; Phillips, Christophe

2012-04-26

452

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

453

Process Acceptance and Adjustment Techniques for Swiss Automatic Screw Machine Parts. Final Report.  

National Technical Information Service (NTIS)

Product tolerance requirements for small, cylindrical, piece parts produced on swiss automatic screw machines have progressed to the reliability limits of inspection equipment. The miniature size, configuration, and tolerance requirements (plus or minus 0...

J. M. Robb

1976-01-01

454

On Electro Discharge Machining of Inconel 718 with Hollow Tool  

NASA Astrophysics Data System (ADS)

Inconel 718 is a nickel-based alloy designed for high yield, tensile, and creep-rupture properties. This alloy has been widely used in jet engines and high-speed airframe parts in aeronautic application. In this study, electric discharge machining (EDM) process was used for machining commercially available Inconel 718. A copper electrode with 99.9% purity having tubular cross section was employed to machine holes of 20 mm height and 12 mm diameter on Inconel 718 workpieces. Experiments were planned using response surface methodology (RSM). Effects of five major process parameters—pulse current, duty factor, sensitivity control, gap control, and flushing pressure on the process responses—material removal rate (MRR) and surface roughness (SR) have been discussed. Mathematical models for MRR and SR have been developed using analysis of variance. Influences of process parameters on tool wear and tool geometry have been presented with the help of scanning electron microscope (SEM) micrographs. Analysis shows significant interaction effect of pulse current and duty factor on MRR yielding a wide range from 14.4 to 22.6 mm3/min, while pulse current remains the most contributing factor with approximate changes in the MRR and SR of 48 and 37%, respectively, corresponding to the extreme values considered. Interactions of duty factor and flushing pressure yield a minimum surface roughness of 6.2 ?m. The thickness of the sputtered layer and the crack length were found to be functions of pulse current. The hollow tool gets worn out on both the outer and the inner edges owing to spark erosion as well as abrasion due to flow of debris.

Rajesha, S.; Sharma, A. K.; Kumar, Pradeep

2012-06-01

455

Electrolytic Machining Development.  

National Technical Information Service (NTIS)

An investigation of electrolytic or electrochemical machining - a metal removal method is described and the advantages over other machining methods are reported. Special emphasis was given to: investigating effects of process variables, including electrol...

J. Bayer M. A. Cummings A. U. Jollis

1964-01-01

456

Cutting cured carbon fiber composites using electrical discharge machining  

SciTech Connect

Traditionally, composite materials are cut using mechanical (solid tool) methods (drilling, milling, grinding, etc) or one of the newer cutting methods such as water jet or laser. All of these methods have serious disadvantages, especially when cutting sharp radii and/or working within close tolerances. The electrical discharge machining (EDM) method offers new opportunities to cut conductive composite materials (such as those containing carbon fibers) with excellent accuracy and minimum damage to the composite part.

Strong, A.B.; Crockett, T.; Merrell, R.S.; Dredge, J.D. Jr. (Brigham Young Univ., Provo, UT (United States))

1991-04-01

457

Influence of steel type on electrical discharge machined surface integrity  

Microsoft Academic Search

This paper studies the influence of type of steel on electrical discharge machined (EDM) surface integrity. Tests were performed with two hardenable steels (tool steel type X155CrMoV12 and high carbon content steel type C90) and two non-hardenable steels (austenitic stainless steel type X2CrNiMo17-12-02 and ferritic stainless steel type X6Cr17). Surface integrity was characterized by roughness, micro-hardness, residual stress distribution and

F Ghanem; C Braham; H Sidhom

2003-01-01

458

Bending strength analysis of micro WC-shaft manufactured by micro electro-discharge machining  

Microsoft Academic Search

Micro electro-discharge machining (micro-EDM) is a critical technology to fabricate high aspect ratio 3D micro-components.\\u000a However, the surfaces of micro-components manufactured by micro-EDM will exhibit micro-cracks to produce notch effects, and\\u000a lead to stress concentrate and reduction of fatigue strength. This paper performs micro-bending tests to investigate the influence\\u000a of various roughness and size on the bending fracture strength of

Biing Hwa Yan; Sheng Ho Huang; Fuang Yuan Huang

2006-01-01

459

Combining programs and state machines  

Microsoft Academic Search

State machines consume and process actions complementary to programs issuing actions. State machines maintain a state and reply with a boolean response to each action in their interface. As state machines offer a service to programs, their interface is also called a service interface. State machines can be combined with several natural operators, thus giving rise to a state machine

Jan A. Bergstra; Alban Ponse

2002-01-01

460

Economic Decision Making Model for Geothermal Sludge Disposal alternatives (EDM-GSD): Version 1. 0  

SciTech Connect

The Economic Decision Making Model for Geothermal Sludge Disposal Alternatives-Version 1.0'' (EDM-GSD 1.0) is a microcomputer-based dynamic model developed to assist in determining the benefits and costs of various geothermal solid waste treatment procedures. It is intended for use by geothermal managers in dealing with geothermal waste and treatment process issues as a means to assist in overcoming the technical and economic barriers to expanded geothermal energy utilization. The model is based on a 50MW flash plant. However, it is designed to provide the user with sufficient flexibility when inputing data to analyze all types of geothermal plants. Default values for economic and technical parameters can be overridden by the user through the input of specific data. In addition, data can be changed for any year of an analysis to account for desired changes in input parameters such as costs and distance to disposal sites. The results of the model will allow the user to: Determine current geothermal plant disposal costs; Evaluate the cost-effectiveness of alternative treatment techniques; and Evaluate the economic effects of changes in disposal regulations.

Not Available

1987-09-01

461

Electric-Discharge Machining Techniques for Evaluating Tritium Effects on Materials  

Microsoft Academic Search

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

2003-01-01

462

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

Microsoft Academic Search

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

2004-01-01

463

A Parametric Study of Dimensional Tolerance and Hydrodynamic Debris Removal in Micro-Electro-Discharge Machining  

Microsoft Academic Search

This paper reports a detailed evaluation of batch mode micro-electro-discharge machining (?EDM) of 316L stainless steel. Lithographically fabricated copper tools with parallel line features of 5-50 ?m width and 5-75 ?m spacing were used to quantify trends in machining tolerance and the impact of debris accumulation. As tool feature density increased, debris accumulation effects began to dominate, eventually destroying both

Mark T. Richardson; Yogesh B. Gianchandani; Dawn S. Skala

2006-01-01

464

Challenges and opportunities in the search for electric dipole moment (EDM) in ^225Ra atom  

NASA Astrophysics Data System (ADS)

The observation of a permanent electric dipole moment (EDM) in a non-degenerate system would indicate violation of time reversal symmetry. ^225Ra atom is a particularly attractive candidate for this search since it has a nuclear spin I=1/2 and has a significant nuclear octupole deformation. This property increases the Schiff moment of the nucleus and therefore enhances the atomic EDM. The half life (t1/2 =14.9 days) of ^225Ra is sufficiently long to perform EDM searches. Our group has already demonstrated the trapping of laser cooled Ra atoms in a magneto-optical trap (MOT) and transferring them to a far off resonant optical dipole trap (ODT). We will discuss our recent progress on manipulation of ultra cold Ra atoms in the ODT, efforts in improving our laser systems and generation of electric and magnetic fields required for the measurement.

Ranjan Kalita, Mukut; Bailey, Kevin; Dietrich, Matthew; Greene, John; Holt, Roy; Korsch, Wolfgang; Lu, Zheng-Tian; Mueller, Peter; O'Connor, Thomas; Parker, Richard; Sulai, Ibrahim; Singh, Jaideep

2011-10-01

465

Single-machine group scheduling with linearly decreasing time-dependent setup times and job processing times  

Microsoft Academic Search

This paper considers single-machine scheduling problems with group technology (GT). We consider the case of group setup times\\u000a and job processing times are a decreasing function of their starting time. We first prove that the makespan minimization problem\\u000a remains polynomially solvable under the general decreasing linear deterioration. We then prove that the total weighted completion\\u000a time minimization problem remains polynomially

Ji-Bo Wang; Linyan Sun

2010-01-01

466

Electrical Conditions of Electrical Discharge Machining with Powder Suspended in Working Oil for Titanium Carbide Accretion Process  

Microsoft Academic Search

This paper describes effects of the discharge current and the pulse duration on a TiC accretion process by electrical discharge machining. Ti powder directly mixed in working oil reacts with the cracked carbon from the working oil then a TiC layer is deposited on a workpiece surface. A thickness of the TiC layer becomes the maximum at certain discharge current

Katsushi Furutani

2003-01-01

467

Structural planning and implementation of a microprocessor-based human-machine interface in a steam-explosion process application  

Microsoft Academic Search

In this paper, small-scale microprocessor-based human–machine interface (HMI) and programmable logic controller (PLC) standard software libraries are applied to plan, design, implement, and construct models for creating the modular application software. The graphical user interface (GUI) functions used in a specific biomass steam-explosion process, intended to be integrated with the PLC device for HMI, thereby providing excellent GUI-based supervision and

Ruey-Fong Chang; Chen-Wei Chang; Kuo-Hsiung Tseng; Cheng-Lun Chiang; Wen-Shiow Kao; Wen-Jang Chen

2011-01-01

468

Experimental Study of Re-impregnation Characteristics for Aged DC Machine and Effect of Application of Far Infrared Radiation to the process  

NASA Astrophysics Data System (ADS)

Recently hundreds of large dc machines manufactured for steel rolling mills at the high growing period are on the verge of replacement due to insulation deterioration of their armature windings after more than thirty years of service operation. Insulation technologies for aged machine are different from those for new machine, including varnish impregnation technologies. In this paper, experimental study of basic impregnation characteristics for aged dc machine to extend its life is described. Experimental study of application of far infrared radiation for the process is also presented.

Kiyokawa, Shin; Inoue, Haruo; Hirose, Haruo; Morita, Noboru

469

[Proceedings of the] International Conference on Educational Data Mining (EDM) (3rd, Pittsburgh, PA, July 11-13, 2010)  

ERIC Educational Resources Information Center

The Third International Conference on Data Mining (EDM 2010) was held in Pittsburgh, PA, USA. It follows the second conference at the University of Cordoba, Spain, on July 1-3, 2009 and the first edition of the conference held in Montreal in 2008, and a series of workshops within the AAAI, AIED, EC-TEL, ICALT, ITS, and UM conferences. EDM 2011…

Baker, Ryan S. J. d., Ed.; Merceron, Agathe, Ed.; Pavlik, Philip I., Jr., Ed.

2010-01-01

470

Proceedings of the International Conference on Educational Data Mining (EDM) (5th, Chania, Greece, June 19-21, 2012)  

ERIC Educational Resources Information Center

|The 5th International Conference on Educational Data Mining (EDM 2012) is held in picturesque Chania on the beautiful Crete island in Greece, under the auspices of the International Educational Data Mining Society (IEDMS). The EDM 2012 conference is a leading international forum for high quality research that mines large data sets of educational…

International Educational Data Mining Society, 2012

2012-01-01

471

Charging machine  

DOEpatents

A charging machine for loading fuel slugs into the process tubes of a nuclear reactor includes a tubular housing connected to the process tube, a charging trough connected to the other end of the tubular housing, a device for loading the charging trough with a group of fuel slugs, means for equalizing the coolant pressure in the charging trough with the pressure in the process tubes, means for pushing the group of fuel slugs into the process tube and a latch and a seal engaging the last object in the group of fuel slugs to prevent the fuel slugs from being ejected from the process tube when the pusher is removed and to prevent pressure liquid from entering the charging machine.

Medlin, John B. (Newark, DE)

1976-05-25

472

Clarification of the Amount of Machining Error Resulting from the Cutting Force and Thermal Expansion during the Cylinder Liner Boring Process  

Microsoft Academic Search

It is well known that the total machining errors of the engine cylinder liner are mainly dominated by the elastic deformation caused by the cutting force and the thermal expansion caused by the temperature rise during the boring process. Clarification of the amount of machining errors resulting from the cutting force and thermal expansion is useful for determining whether thermal

Yulong Tang; Kan Ding; Hiroyuki Sasahara; Kimio Nishimura; Takafumi Watanabe

2008-01-01

473

Determining cutting parameters in wire EDM based on workpiece surface temperature distribution  

Microsoft Academic Search

The material removal process in wire electrical discharge machining (WEDM) may result in work-piece surface damage due to\\u000a the material thermal properties and the cutting parameters such as varying on-time pulses, open circuit voltage, machine cutting\\u000a speed, and dielectric fluid pressure. A finite element method (FEM) program was developed to model temperature distribution\\u000a in the workpiece under the conditions of

S. Keith Hargrove; Duowen Ding

2007-01-01

474

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.

Wgbh

2010-01-01

475

A novel laser micro\\/nano-machining system for FPD process  

Microsoft Academic Search

Laser machining technology has potential to be adopted as micro- and nano-fabrication equipments in the field of flat panel display (FPD) industry. The equipments repair short, open or protrusion defects by cutting and welding using high-power laser. The equipments should be able to carry large sized mother glass and have high productivity and accuracy. To meet the requirements, the equipment

Kihyun Kim; Young-Man Choi; Dea-Gab Gweon; Moon G. Lee

2008-01-01

476

Single Machine Scheduling with Deadlines and Increasing Rates of Processing Times  

Microsoft Academic Search

Abstract: This paper considers the single-machine scheduling problem in which thejob release dates can be compressed while incurring additional costs. The twocriteria are maximum lateness and compression cost. For the case of equal jobprocessing times, an O(n) algorithm is developed to construct the breakpointsof a piecewise linear ecient frontier. The complexity status of the problem withother scheduling criteria is also

T. C. Edwin Cheng; Qing Ding

2000-01-01

477

Support vector machines for quality monitoring in a plastic injection molding process  

Microsoft Academic Search

Support vector machines (SVMs) are receiving increased attention in different application domains for which neural networks (NNs) have had a prominent role. However, in quality monitoring little attention has been given to this more recent development encompassing a technique with foundations in statistic learning theory. In this paper, we compare C-SVM and ?-SVM classifiers with radial basis function (RBF) NNs

Bernardete Ribeiro

2005-01-01

478

FACOM VP Supercomputer of Parallel Pipeline Processing System Has Achieved 7.5 Ns Machine Cycle.  

National Technical Information Service (NTIS)

At the end of 1983 Fujitsu will begin to deliver its FACOM VP supercomputer, which has a machine cycle of 7.5 ns and a maximum performance of 53 MFLOPS. Its main storage can be expanded to 256 megabytes, and 64 kiloBIT static RAMs with an access time of 5...

T. Hiraguri A. Tabata T. Tsuchimoto S. Taguchi

1985-01-01

479

Influence of circuit parameters on the electric discharge machining of the bearings of a PWM inverter driven motor  

Microsoft Academic Search

In inverter motor drives an increasing fraction of faults is associated to the bearings damages induced by circulating currents. In particular, the capacitive couplings between the stator and the rotor give rise to a shaft voltage which, in turn, may produce the breakdown of the lubricating film in the bearings and the associated electric discharge machining (EDM) currents. By using

B. De Vivo; L. Egiziano; P. Lamberti; V. Tucci

2008-01-01

480

Real-Time Wavelet Transform for Image Processing on the Cellular Neural Network Universal Machine  

Microsoft Academic Search

A novel algorithm for achieving Wavelet transform on the Cellular Neural Network Universal Machine (CNN-UM) visual neuroprocessor\\u000a is presented in this work. The CNN-UM is implemented on a VLSI programmable chip having real time and supercomputer power.\\u000a This neurocomputer is a large scale nonlinear analog circuit made of a massive aggregate of regularly spaced neurons which\\u000a communicate with each other

Victor M. Preciado

2001-01-01

481

Statistical Process Control (SPC) for Coordinate Measurement Machines. Using SPC and Monitoring of Standard Artifacts to Determine and Control Measurement Uncertainty in a Controlled Environment.  

National Technical Information Service (NTIS)

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 e...

R. N. Escher

2002-01-01

482

Machine vision  

SciTech Connect

To keep up with the speeds of modern production lines, most machine vision applications require very powerful computers (often parallel-processing machines), which process millions of points of data in real time. The human brain performs approximately 100 billion logical floating-point operations each second. That is 400 times the speed of a Cray-1 supercomputer. The right software must be developed for parallel-processing computers. The NSF has awarded Rensselaer Polytechnic Institute (Troy, N.Y.) a $2 million grant for parallel- and image-processing software research. Over the last 15 years, Rensselaer has been conducting image-processing research, including work with high-definition TV (HDTV) and image coding and understanding. A similar NSF grant has been awarded to Michigan State University (East Lansing, Mich.) Neural networks are supposed to emulate human learning patterns. These networks and their hardware implementations (neurocomputers) show a great deal of promise for machine vision systems because they allow the systems to understand the use sensory data input more effectively. Neurocomputers excel at pattern-recognition tasks when input data are fuzzy or the vision algorithm is not optimal and is difficult to ascertain.

Horn, D.

1989-06-01

483

An experimental search on the electron EDM based on solid-state techniques  

NASA Astrophysics Data System (ADS)

A discovery of a permanent electric dipole moment of the electron (eEDM) would provide crucial information about the nature of T-violation and imply new sources of CP-violation beyond the Standard Model. We are pursuing research that would improve the present experimental limit of the eEDM using a new technique in solid-state systems at 4K. The experiment uses a Gadolinium Gallium Garnet sample with a large magnetic response, which can be measured using the Superconducting Quantum Interference Device as the magnetometer. In this talk, I will discuss the progress to control the systematic effects, including the design and implementation of a 24-bit DAQ system with ultra-low level of channel crosstalk, and the control of the high voltage drift from the supply. With significant progress, finally we push the experimental limit of eEDM on the order of 10-25e cm under four days integration time of data, which is most sensitive results ever achieved using the solid state technique. In addition, the experiment is free of sources that could produce spurious signal at this level. Further enhancement of the eEDM sensitivity would require operating the experiment at sub-Kelvin temperatures.

Kim, Young Jin; Liu, Chen-Yu

2010-11-01

484

Simple Machines  

NSDL National Science Digital Library

This activity is designed to learn about simple machines and to have fun doing so! First, use this website to learn backround information on the basics of simple machines. Try the quiz! Simple Machines Learning Site Next, play a game that tests your ability to identify simple machines.... Edheads: Simple Machines Finally, view this video to see how students your age used applied simple machines to do a cool task... Building Simple Machines: A Glass of Milk, Please ...

Awol

2006-11-15

485

Preliminary design and manufacturing feasibility study for a machined Zircaloy triangular pitch fuel rod support system (grids) (AWBA development program)  

SciTech Connect

General design features and manufacturing operations for a high precision machined Zircaloy fuel rod support grid intended for use in advanced light water prebreeder or breeder reactor designs are described. The grid system consists of a Zircaloy main body with fuel rod and guide tube cells machined using wire EDM, a separate AM-350 stainless steel insert spring which fits into a full length T-slot in each fuel rod cell, and a thin (0.025'' or 0.040'' thick) wire EDM machined Zircaloy coverplate laser welded to each side of the grid body to retain the insert springs. The fuel rods are placed in a triangular pitch array with a tight rod-to-rod spacing of 0.063 inch nominal. Two dimples are positioned at the mid-thickness of the grid (single level) with a 90/sup 0/ included angle. Data is provided on the effectiveness of the manufacturing operations chosen for grid machining and assembly.

Horwood, W.A. (ed.)

1981-07-01

486

Clarification of the Amount of Machining Error Resulting from the Cutting Force and Thermal Expansion during the Cylinder Liner Boring Process  

NASA Astrophysics Data System (ADS)

It is well known that the total machining errors of the engine cylinder liner are mainly dominated by the elastic deformation caused by the cutting force and the thermal expansion caused by the temperature rise during the boring process. Clarification of the amount of machining errors resulting from the cutting force and thermal expansion is useful for determining whether thermal expansion or the cutting force has a larger influence on machining errors during the boring process. This would provide a clear approach to the optimization of cutting conditions or to product improvement, leading to a higher degree of machining accuracy. In this paper, in order to clarify the amount of machining errors, the machining error caused by the thermal expansion apart from the elastic deformation of a cylinder liner caused by the cutting force was first determined. For this purpose, an experimental method is suggested in this paper. The temperature rise that causes the thermal expansion of the cylinder liner was simulated by a YAG laser heating process instead of by an actual boring process. During this heating process, the machining errors caused by the thermal expansion could be solely investigated. First, an actual cylinder boring process was performed (cutting speed: 900 m/min, feed rate: 0.2 mm/rev, depth of cut: 0.3 mm, dry cutting). The total machining errors caused by the cutting force and thermal expansion were measured. Then, the YAG laser heating experiment was also carried out. Comparing the results between the two experiments, it was clarified that the thermal expansion of the cylinder liner caused by the cutting energy is dominant and the deflection caused by the cutting force is small.

Tang, Yulong; Ding, Kan; Sasahara, Hiroyuki; Nishimura, Kimio; Watanabe, Takafumi

487

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

488

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

489

Real-time wireless monitoring of workpiece material and debris characteristics in micro-electro-discharge machining  

Microsoft Academic Search

Wireless signals are generated with each discharge in micro-electro-discharge machining (muEDM), providing an opportunity to directly monitor discharge quality. Unlike traditional methods of monitoring progress in machining, which rely on electrical characteristics at the discharge supply terminals, this method is less affected by parasitics. The depth location of a metal-metal interface can be distinguished in the wireless signal. This is

Mark T. Richardson; Yogesh B. Gianchandani

2008-01-01

490

Literature Survey on Direct Energy Machining.  

National Technical Information Service (NTIS)

The mechanism of various direct energy machining processes is presented. Machine requirements are discussed. Direct energy machining processes, at the present state of the art, are a breakthrough to the solution of shaping of materials which cannot be mac...

C. R. Hyland

1964-01-01

491

Machining: An Introduction  

NSDL National Science Digital Library

Basic machining processes are introduced on this site that is devoted to engineering fundamentals. 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.

2008-04-23

492

Experimental and numerical study of angular error in 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. The so-called taper-cutting involves the generation of inclined ruled surfaces, and it is especially important in the manufacturing of tooling requiring draft angles. In this paper a new approach to the prediction

J. A. Sanchez; S. Plaza; N. Ortega; M. Marcos; J. Albizuri

2008-01-01

493

Introspective Machine.  

National Technical Information Service (NTIS)

An introspective machine, capable of passing judgment on its own deductive performances, is modelled and analyzed. First, the class of ideal machines which is provided with unlimited resources is studied. Since ideal introspective machines are usually unf...

G. A. W. Vreeswijk

1989-01-01

494

On-line collection and transfer of radioactive noble gas isotopes for radon EDM measurements  

NASA Astrophysics Data System (ADS)

An apparatus has been developed for on--line collection and transfer to a measurement cell of radon isotopes for optical pumping studies and electric dipole moment (EDM) measurements. Specific isotopes are predicted to have large atomic EDMs due to nuclear octupole deformation or vibration resulting in enhanced sensitivity to CP violation. A low energy isotope separator beam is stopped in a foil. After collection, the foil is heated and the noble gas atoms are cryopumped to a cold finger and then transferred with a buffer gas to a measurement cell. The apparatus has been tested with ^120Xe produced from a ^120Cs beam at the TRIUMF ISAC facility, and greater than 40% efficiency for transfer from the foil to the cell has been demonstrated. The apparatus may also be useful for other measurements with gaseous targets including laser spectroscopy and precision half--life measurements.

Nuss-Warren, Sarah; Tardiff, Eric; Warner, Tim; Ball, Gordon; Behr, John; Chupp, Tim; Coulter, Kevin; Hackman, Greg; Hayden, Michael; Pearson, Matthew; Phillips, Andrew; Smith, Martin; Svensson, Carl

2004-05-01

495

CATSI EDM: recent advances in the development and validation of a ruggedized passive standoff CWA sensor  

NASA Astrophysics Data System (ADS)

Defence Research and Development Canada (DRDC) - Valcartier is currently developing a ruggedized passive standoff sensor for the detection of chemical warfare agents (CWAs) based on differential Fourier-transform infrared (FTIR) radiometry. This system is referred to as the Compact ATmospheric Sounding Interferometer (CATSI) Engineering Development Model (EDM). The CATSI EDM sensor is based on the use of a double-beam FTIR spectrometer that is optimized for optical subtraction. A description of the customized sensor is given along with a discussion on the detection and identification approaches that have been developed. Preliminary results of validation from a number of laboratory measurements and open-air trials are analyzed to establish the capability of detection and identification of various toxic and non-toxic chemical vapor plumes. These results clearly demonstrate the capability of the passive differential radiometric approach for the standoff detection and identification of chemical vapors at distances up to a few kilometers from the sensor.

Lavoie, Hugo; Thériault, Jean-Marc; Bouffard, François; Puckrin, Eldon; Turcotte, Caroline S.; Lacasse, Paul

2008-05-01

496

A study on the machining-parameters optimization of wire electrical discharge machining  

Microsoft Academic Search

A suitable selection of machining parameters for the wire electrical discharge machining (WEDM) process relies heavily on the operators' technologies and experience because of their numerous and diverse range. Machining-parameters tables provided by the machine-tool builder can not meet the operators' requirements, since for an arbitrary desired roughness of the machining surface, they do not provide the optimal machining conditions.

Y. S. Liao; J. T. Huang; H. C. Su

1997-01-01

497

Machine Shop Grinding Machines.  

ERIC Educational Resources Information Center

|This curriculum manual is one in a series of machine shop curriculum manuals intended for use in full-time secondary and postsecondary classes, as well as part-time adult classes. The curriculum can also be adapted to open-entry, open-exit programs. Its purpose is to equip students with basic knowledge and skills that will enable them to enter…

Dunn, James

498

Machine Shop Grinding Machines.  

ERIC Educational Resources Information Center

This curriculum manual is one in a series of machine shop curriculum manuals intended for use in full-time secondary and postsecondary classes, as well as part-time adult classes. The curriculum can also be adapted to open-entry, open-exit programs. Its purpose is to equip students with basic knowledge and skills that will enable them to enter the…

Dunn, James

499

Multivariable identification of paper machine cross-direction process using an automated tool  

Microsoft Academic Search

The accurate identification of the mapping between the cross-direction (CD) actuators and the scanned profiles of paper CD properties requires reliable processing of test data which takes into account paper shrinkage and misalignment. This paper describes a new tool which can automate this identification process. The new tool covers all aspects of CD process identification including excitation of the paper

Michael Heaven; Dimitry Gorinevsky; Chris Sung; M. Kean

1997-01-01

500

Modeling of the carbon dioxide capture process system using machine intelligence approaches  

Microsoft Academic Search

Improving the efficiency of the carbon dioxide (CO2) capture process requires a good understanding of the intricate relationships among parameters involved in the process. The objective of this paper is to study the relationships among the significant parameters impacting CO2 production. An enhanced understanding of the intricate relationships among the process parameters supports prediction and optimization, thereby improving efficiency of

Qing Zhou; Yuxiang Wu; Christine W. Chan; Paitoon Tontiwachwuthikul

2011-01-01