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Wire EDM cutting of PCD
報告者：陳思懿
指導教授:戴子堯 博士
Outline
• INTRODUCTION
• Influence of PCD machining
conditions
• Conclusions
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INTRODUCTION
• polycrystalline diamond is a synthetic composite cutting
tool material produced by sintering together carefully
selected diamond particles under conditions of high
temperature and high pressure. the interstitial spaces in
the diamond matrix are predominantly filled with cobalt,
PCD is usually offered with a tungsten carbide (WC-Co)
substrate.
• Electrical discharge machining (EDM) offers advantages
over conventional techniques such as grinding and lapping
in the machining of polycrystalline diamond tools in terms
of process reliability and the flexibility offered by the
technique for machining different shapes.
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Quality characteristics
Fig 1 PCD/carbide offset(dimensional difference ).PCD undercut
and PCD/carbide notch.
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Influence of PCD grade 1/2
Fig 2 Cutting rate and surface finish as a function of pulse frequency for various
PCD grades and tungsten carbide.
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Influence of PCD grade 2/2
Fig 3 SEM photographs of the cut surfaces of different PCD grades and
tungsten carbide.
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Influence of wire material
Fig 4 Cutting rate and surface
quality as a function of
wire characteristics.
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Influence of the working
Medium 1/2
Fig 5 Cutting rate and surface quality depending on the
dielectric fluid.
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Influence of the working
Medium 2/2
Fig 6 comparison of the surface topography of PCD samples eroded in a
water bath and in an oil bath.
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Conclusions
• PCD can be machined reproducibly to a high surface quality
using the wire EDM technique.
• The machining results are largely determined by the type of
wire material selected and the type of dielectric fluid .
• Wires with high electrical conductivity and a low concentration
of zinc on the surface are to be preferred.
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Thanks for your attention！！
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