Study of electrical discharge machining using powder-suspended working media

Abstract

This paper reports investigations of electrical discharge machining (EDM) using a powder-suspended working fluid instead of a pure dielectric. The EDM characteristics obtained using hydrocarbon dielectric (kerosene) and a mixture of deionized water with abrasive powder have been compared. The relationships between surface roughness parameters, material removal rate and operating parameters of EDM have been determined for different kinds of powder and concentration in kerosene/water.

Austenitic steel surface integrity after EDM in different dielectric liquids

“…Many authors [4,17,26] point to the crucial role of the dielectric type in electrodischarge machining. Dielectrics ensure the possibility of the occurrence of controlled electrical discharges between the tool electrode and the workpiece, cooling and solidifying of gaseous EDM debris from the discharge, removing erosion products from the machining gap and also dispersing heat generated during the process from the tool electrode and workpiece material [4].…”

“…Dąbrowski [6,17] points out that the main factors which influence the machined element's surface integrity are current intensity and pulse time, while the other machined parameters are defined. The current intensity increases the results in a higher amount of material removal during a single discharge.…”

Environmentally friendly trends in electrical discharge machining (EDM)

“…16. Zdjęcia drążonego otworu na mokro, sucho i z minimalną ilością dielektryka [9] Odmianą drążenia z minimalnym dopływem dielektryka umożliwiającą zwiększenie stabilności procesu, wydajności i gładkości powierzchni po drążeniu na sucho jest drążenie z zastosowaniem medium w postaci mieszaniny cieczy dielektryka, gazu i nanoproszków (powder mixed near dry elektrical discharge machining PMND-EDM) [2,10,24]. W dotychczas przeprowadzonych badaniach stosowano sproszkowany grafit, aluminium, krzem, węglik krzemu i siarczek molibdenu o wielkości ziarna od 70-80 nm.…”

Experimental Investigation of Surface Layer Properties of High Thermal Conductivity Tool Steel after Electrical Discharge Machining

“…The properties of the changed layers have a strong influence on abrasion resistance, hardness, corrosion resistance, resistance to thermal shocks, coating quality and more. Improving the quality of the surface Metals 2017, 7, 550 2 of 16 integrity after the EDM process can be realized by electro discharge mechanical alloying [15,16], laser surface modification [17][18][19][20][21], the use of powders in dielectric [22,23], hybrid-machining [24], or coatings [25,26]. Research conducted in the field of EDM technology focuses primarily on a better understanding of the physical phenomenon of the process [27,28], monitoring the machining [29,30], improving surface quality and the material removal rate [31,32], optimization of process technology [33][34][35][36], analyses of surface layers properties [37,38] and new methods of forming difficult to manufacture materials [39].…”