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Effect of micro-powder suspension
and ultrasonic vibration of dielectric
fluid in micro-EDM processes－
Taguchi approach
指導老師：戴子堯 教授
學生：杜弘翔 4A014059
報告日期：2015/06/01
Outline
• 1. Introduction
• 2. Experimental setup
• 3. Results and discussion
• 4. Conclusions
• 1. Introduction
• 2. Experimental setup
• 3. Results and discussion
• 4. Conclusions
• One of the problems is poor flushing away of
machining debris.
• They found the particle concentration, the
electrical resistivity, and the thermal
conductivity of powders are important
characteristics that significantly affect the
machining performance in the EDM process.
• 1. Introduction
• 2. Experimental setup
• 3. Results and discussion
• 4. Conclusions
• 1. Avoid micro-powder accumulating at the
bottom of the tank.
• 2. Increase the kinetic energy of discharge
debris.
• This causes the debris to be removed more
easily; as a result fewer short-circuits occurred
in discharging.
2.1. Configurations of experiment
factors and their levels
• 1. Ultrasonic vibration of the dielectric fluid.
Yes or Not
• 2. Micro-MoS2 powder concentration.
Pure, 2g/l, 5g/l
• 3. Tool electrode material.
Cu, Cu-W, Brass
• 4. Workpiece material.
Cu, Cu-W, Ag-W
• 1. Introduction
• 2. Experimental setup
• 3. Results and discussion
• 4. Conclusions
3.1. Combination of optimal level for
each factor and verification test
3.2. Effect of ultrasonic vibration of
dielectric fluid on material removal rate
3.3. Effect of powder concentration on
material removal rate
3.4. Effect of workpiece and tool
electrode material on material removal
rate
3.5. Effect of dielectric containing micropowder in micro-EDM on surface
microstructure
• Cu–W surface, brass as the tool electrode,
using a pure dielectric fluid.
• Cu–W surface, brass as the tool electrode,
using MoS2 powder with ultrasonic vibration
of dielectric fluid and a powder concentration
of 2g/l.
• 1. Introduction
• 2. Experimental setup
• 3. Results and discussion
• 4. Conclusions
• 1. A new method in which the addition of
micro-MoS2 powder to a dielectric fluid
combined with ultrasonic vibration of the
dielectric was found to have a significant
effect in increasing the material removal rate
and improving surface quality.
• 2. The high lubricity levels of MoS2 also help
to improve surface quality.
• 3. The ultrasonic vibration of a dielectric fluid
is significant in increasing the material
removal rate.
• 4. Cu is easier to machine with mirco-EDM
processes using micro-MoS2 powder
suspended in a dielectric than with Cu–W or
Ag–W.
• 5. Using brass as the tool electrode is not a
significant factor in obtaining a high material
removal rate.
References
• IEEE：Effect of micro-powder suspension and
ultrasonic vibration of dielectric fluid in microEDM processes-Taguchi approach