Synthesis and Characterization of Titanium
and Graphite Powder Mixed Electric
Discharge Machining on Inconel 718
Sovan Bhowmick
a,1
, Arindam Paul
b
, Nisantika Biswas
c
, Jhumpa De
c
, Subhasish Sarkar
a
and Gautam Majumdar
a
a
Mechanical Engineering Department, Jadavpur University, India.
b
Department of Metallurgical and Material Engineering, Jadavpur University, India.
c
Department of Mechanical Engineering, Academy of Technology, India.
Abstract. Electric discharge machining is extensively used to process difficult to
cut materials such as superalloys, composite materials etc. The quality of machining
can be improved by adding particles into the dielectric fluid which is commonly
known as powder mixed electric discharge machining (PMEDM). In the present
study, titanium and graphite powder are added to dielectric fluid and the effects of
the powders have been analysed on material removal rate, surface roughness,
microhardness and surface morphology analysis. Six experiments have been
conducted considering each powder with three different levels of pulse current 4A,
8A and 12A. The analysis of the result indicates MRR, surface roughness and
microhardness significantly increase with the increase of pulse current. Titanium
mixed EDM improves the MRR and microhardness but reduces the surface quality.
The SEM investigations elucidate that the samples machined with Titanium powder
mixed with EDM have fewer surface defects, cracks, microholes and layer
deposition compared to the sample machined with Graphite powder.
Keywords. Powder mixed electric discharge machining, MRR, surface roughness,
microhardness, SEM.
1. Introduction
Electric discharge machining is a non-traditional machining process commonly used for
machining or cutting conductive materials having poor machinability like superalloys,
high strength alloys, composite materials etc. A die-sinking EDM is used in the tool and
die manufacturing industry. The mechanism of the material removal is thermal corrosion
that occurs on the surface of the workpiece. The difficulties faced during the machining
are poor surface finish, low production rate, and poor surface integrity [1]. Several
researches were done to enhance the surface quality and production rate out of which the
most significant improvement is witnessed when the conductive metallic powder is
added to the dielectric fluid during the machining process. In a study, The effect of
graphite nanopowder on deionized water was investigated on Inconel 825 alloy and
found a considerable improvement in MRR, surface quality and tool wear rate [2].
_______________________________
1
Corresponding Author, Mechanical Engineering Department, Jadavpur University, Kolkata-700032
India, Email: svnbhowmick1@gmail.com
Advanced Production and Industrial Engineering
R.M. Singari and P.K. Kankar (Eds.)
© 2022 The authors and IOS Press.
This article is published online with Open Access by IOS Press and distributed under the terms
of the Creative Commons Attribution Non-Commercial License 4.0 (CC BY-NC 4.0).
doi:10.3233/ATDE220722
58