During electrodischarge machining (EDM) the topography and metallurgical and physicochemical properties of the surface layer change considerably. Under certain conditions, the metal transfer from the tool electrode to the machined surface is also appreciable. By employing suitable process parameters, surface modification for desired functional behaviour is possible by EDM. In this paper, the metal transfer from the tool electrode is studied by cross-sectional examination, electron spectroscopy for chemical analysis and X-ray diffraction analysis of the work surface. The associated changes in the surface topography are analysed by scanning electron microscopy and the harmonic contents of the surface profiles. © 1991.

Shunmugam M S

Department of Mechanical Engineering

P. K. Philip

chemical analysis

METALS AND ALLOYS--SURFACES

Microscopic Examination--Scanning Electron Microscopy

Surfaces--Modification

X-RAY ANALYSIS

ELECTRODISCHARGE MACHINING SURFACE MODIFICATION

METAL SURFACE MODIFICATION

POWDER COMPACT TOOL ELECTRODE

X-RAY DIFFRACTION ANALYSIS

Metal cutting

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Surface modification in electrodischarge processing with a powder compact tool electrode

Wear

Electrodes in electrical discharge machining (EDM) can be compared with cutting tools in conventional machining. Tool performance is one of the important factors that determine the quality of the machined component. Due to the ease of manufacturing and control over the properties of electrodes, the powder metallurgy (P/M) technique has an advantage over other methods of electrode fabrication. P/M electrodes affect the micro-and macrovariables in EDM and the properties of P/M electrodes can be controlled over a wide range by adjusting the compacting and sintering conditions. The performance of P/M electrodes on various aspects of EDM operation is discussed in this paper. Published by Elsevier Science Ltd.

International Journal of Machine Tools and Manufacture

Power metallurgy tool electrodes for electrical discharge machining

Electrodischarge machining with pulsing relaxation generator using a powder compact electrode and reverse polarity setting modifies the surface properties of a machined surface greatly. Using a hard and wear-resistant material in the compact, the wear resistance of the resultant surface can be improved. In the present investigation, tungsten carbide powder is used in the compact. The wear resistance is evaluated by cutting tests and the results show considerable improvement over the uncoated surfaces. © 1994.

Improvement of wear resistance by EDM with tungsten carbide P/M electrode

Metal transfer from the tool electrode to the machined surface is appreciable in electrodischarge machining when a powder compact tool electrode is used under reverse polarity conditions. A powder metallurgy bronze electrode was employed in the present work and investigation of the frictional behaviour of the resultant surface showed considerable reduction in the friction coefficient. Reduction in wear was also confirmed by a new method using cutting tests, establishing that the surfaces can be used in applications involving extreme pressure and velocity. © 1993.

Tribology International

Tribological behaviour of an electrodischarge machined surface with a powder metallurgy bronze electrode

Pulse train studies reveal the typical characteristics of the spark discharges associated with EDM. It has been observed that the use of reverse polarity and a powder-compact tool electrode influences the discharge phenomenon and results in an appreciable amount of deposition on the work surface. In the present investigation, electro-discharge machining has been carried out using combined pulse generation and a relaxation circuit which also enhances the tool electrode transfer and the pulse trains have been recorded using a dual-trace storage oscilloscope and an X-Y plotter. © 1992.

Pulse train studies in EDM with controlled pulse relaxation

The fabrication of micro products is gradually expanding due to their need in micro feature-based frameworks, which require a multitude of functions to be integrated. Electro discharge deposition (EDD) is an emerging additive manufacturing process to create micro products. In the present paper, simulation of an EDD process has been investigated in the presence and absence of maximum magnetic flux density. In the first stage of simulation, a thermo-physical model has been developed to find the melt volume in single pulse discharge. In the second stage, initially the optimum orientation and location of the magnet to be placed around the EDD plasma are identified, and subsequently, in the presence of maximum magnetic flux density, heavy species transport is used to study the impact of the process on the height and weight of deposition. Experiments are carried out to validate the simulation results. From the results obtained it is observed that the height of deposition is increased by 23.5% in the presence of the magnetic field. © 2019 IOP Publishing Ltd.

Journal of Micromechanics and Microengineering

Effect of magnetic field intensity on deposition of copper tool in electro discharge deposition

B.T.A. drills are capable of machining holes having a large length to diameter ratio in a single pass to a higher degree of accuracy and surface finish. This is a unique self piloted operation in which cutting and burnishing are carried out at the same time. The accuracy of the hole in the axial as well as transverse sections is controlled by such a unique operation. In this paper, a complete profile analysis has been carried out in the axial and transverse directions. The results throw more light on the process characteristics and these are useful in the control of the process. © 1987.

Analysis of axial and transverse profiles of holes obtained in B.T.A. machining

CIRP Annals

Physical and Technological Control of Arc Dimensional Machining

Metals Technology

High-rate spark hardening of hot-forging dies

Mineralogical Magazine

(L. G.) Berry, Editor. Selected powder diffraction data for minerals. Data book. Swarthmore, Pennsylvania (Joint Committee on Powder Diffraction Standards), 1974. xlvi + 833 pp.

Proceedings of the Institution of Mechanical Engineers

A New Unified Approach to Surface Metrology

Journal	Wear
ISSN	00431648
Open Access	No