• Transactions of Materials Processing
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• v.6 no.3
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• pp.192-202
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• 1997

This study presents an effect of number of passes in wire-cut electric discharge machining on fine blanking dies and products. Three part fine blanking dies were produced by the difference of numbers of passes discharge machining. Brake pad was produced, through the die produced like that, the objective of this study is the improvement in surface roughness of die block and punch, life extension of die block, the decrease of second fracture dimensions, the rise of productive.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.6
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• pp.15-21
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• 2006

This work deals with the electrical conductivity of dielectric on output parameters such as metal removal rate and surface roughness value of a carbon steel(SM25C) and sintered carbides cut by wire electrical discharge machining (WEDM). Dielectric has several functions like insulation, ionization, cooling, the removal of waste metal particles. The presence of minute metal particles(debris) in spark gap contaminates and lowers the breakdown strength of dielectric. And it is considered that too much debris in spark gap is generally believed to be the cause of arcing. Experimental results show that increases of cobalt amount in carbides affects the metal removal rate and worsens the surface quality as a greater quantity of solidified metal deposits on the eroded surface. Lower electrical conductivity of the dielectric results in a lower metal removal rate because the gap between wire electrode and workpiece reduced. Especially, the surface characteristics of rough-cut workpiece and wire electrode were analyzed too. Debris were analyzed also through scanning electron microscopy(SEM) and surface roughness tester. Micro cracks and some of electrode material are found on the workpiece surface by energy dispersive spectrometer(EDS).

• 기계와재료
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• v.11 no.2 s.40
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• pp.129-138
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• 1999

• Proceedings of the KAIS Fall Conference
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• 2000.04a
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• pp.7-7
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• 2000

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.930-933
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• 2001

Titanium Alloys used in this experiment has an good corrosion resistance and specific strength, and is the new material developed for medical supplies living goods. In this study the rolled titanium alloy is done by annealing, solution heat-treatment and aging and then is worked by wire EDM. With changing the process conditions, the process properties of surface hardness, surface roughness, shape of process surface and the analysis of ingredients are measured through experiment repeating main cut and finish cut. It is confirmed to gain good measure values as increasing the number of processing of wire EDM. In this experiment the phenomena of processing is studied and the appropriate process condition is proposed.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.10a
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• pp.123-128
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• 2002

The machining parameters for the wire electrical discharge machining(WEDM), including no load voltage, pulse-on time, pulse-off time, wire tension, water flow rata offset etc. should be chosen properly so that a better performance can be obtained An optimum selection of machining parameters relies heavily on the operators technologies and experience. This study presents a method by means of Taguchi method to select optimal machining parameter combination for an cutting speed or surface roughness. Experimental results demonstrate that the machining models are appropriate and the derived machining parameters satisfy the real requirements in notice.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.5
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• pp.101-106
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• 2008

In the wire cut electrical discharge machining, the optimal machining parameters setting satisfying the requirements of both high efficiency and good quality is very difficult because its process involves a series of complex physical phenomena and the machining parameters are numerous over diverse range. In this paper, the experimental investigation has been performed to find out the influence of the machining parameters on the machining performance such as cutting speed and surface roughness. The selected experimental parameters are no load voltage, discharge peak current and pulse-off time. The experimental results give the guideline for selecting suitable machining parameters.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.2
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• pp.322-328
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• 2002

In wire-electrical discharge machining (W-EDM), the dielectric plays an important role as the working fluid. It affects the material removal rate and the properties of the machined surface. This paper deals with the effects of the electrical conductivity of dielectric and cobalt percentage of sintered carbides on the machining characteristics and the machined surface integrities with deionized water as dielectric. A series of experiments have been performed on sintered carbides having different cobalt contents. Experimental results show that a higher cobalt content of WC decreases the metal removal rate and worsens the surface quality. Lower electrical conductivity of the dielectric results in a higher metal removal rate as the gap between wire electrode and workpiece reduced. Especially, the surface integrities of rough-cut workpiece, wire electrode, and debris were analyzed also through scanning electron microscopy(SEM) and surface roughness tester. By energy dispersive spectrometry(EDS), it is confirmed that micro cracks and some of electrode material are found on the workpiece surface.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.6
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• pp.714-719
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• 2011

The surface roughness depending on the machining method is very important because is produce a finished product through riveting, sealing, bonding, and special paint in order to curb the turbulence and air resistance which occur between the sheets. Aluminum alloy 2024 which is widely used for interior and exterior material of aircraft are tested. Jin-young JW-60C wire cutting machine was used in this experiment. In this paper, the experimental investigation has been performed to find out the influence of the surface roughness and surface shape characteristics on the wire-cut EDM of discharge energy in aluminium alloy 2024. The selected experimental parameters are peak current, no-load voltage, off time and feed rate. The experimental results give the guideline for selecting reasonable machining parameters. The high discharge energy on the idle time, almost no change in surface roughness can be seen.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.8
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• pp.143-151
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• 2004

This paper deals with the precision NURBS interpolator for wire-EDM. Previous research about OAC (Open Architecture Controller) is mostly aimed at NC cutting machines such as milling or lathes, and hence these results are inadequate to apply to wire-EDM. In contradiction to NC machines, wire-EDM operates relatively slow feed rates and based on a feedback control loop to the machining process. The 2-stage interpolation method which reflects wire-EDM specific characteristics was proposed. The constant interpolation error could be acquired through 1 st stage interpolation. Feed rate regulation was performed through 2nd stage interpolation. The suggested algorithm was implemented to test-bed PC-NC system. Computer simulations and the experimental machining were conducted.