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Micro-EDM process investigation and comparison
performance of Al3O2 and ZrO2 based ceramic
composites
指導老師:戴子堯
報告者:張瑋民
Outline
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Introduction
Experimental set-up
Process investigation
Material removal mechanism
Machining strategies and applications
Conclusions
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Introduction
• Advanced technical ceramics find extensive applications
in industry. Among them, aluminium oxide and zirconium
oxide are the most widely employed for industrial
machinery applications .
• Among them EDM provides several advantages. Due to
the erosive action of electrical discharges generated
between a tool and workpiece electrode, complex
shapes and intricate profiles with high accuracy and
surface quality are achievable, regardless the workpiece
hardness.
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Experimental set-up
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• The EDM tool applied in this research is a SARIX SX100-HPM, specifically aimed for micro scale applications.
• WC solid rods ( Φ 300 μm) were used as tool electrodes.
The rotational speed was set to 600 rpm and negative
tool polarity was applied through all the experiments.
Experiments were carried out in hydrocarbon oil .
• The test features were true trenches, realized by laterally
sinking the tool electrode into ceramic bars.
• The surface topographies and cross sections were
observed by means of a Scanning Electron Microscope
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Process investigation
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Material removal mechanism
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Machining strategies and applications
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Conclusions
• Both materials show a process behaviour similar to steel.
• Melting/evaporation
mechanism.
is
the
main
material
removal
• Al3O2–TiCN gives a lower surface roughness.
• The generation of subsurface cracks is also observed
which may affect its durability during final applications. On
the contrary, the subsurface damage induced into the
ZrO2–TiN is negligible.
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Thank you for your attention
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