Experimental Study on Influence of Process Variables on Crater Dimensions in Micro- EDM of γ -Titanium Aluminide

Abstract

In the present work the effect of different dielectric mediums in micro-EDM of γ-Titanium Aluminide alloy have been investigated. Experiments were conducted both in the absence (dry conditions) and in presence of dielectric (EDM oil).Circular craters were produced both in the presence and absence of dielectric fluid using varying micro-EDM process variables i.e. open circuit voltage, discharge capacitance, pulse frequency and pulse-on-time. Over cut was measured from optical microscope images using Image Analyzer software. Influences of process variables and optimal conditions for minimum over cut on crater dimensions were investigated. ANOVA test which shows that capacitance of RC circuit contributes significantly in crater formation followed by pulse frequency. Optical photographs exhibit that over cut are less in air medium compared to oil medium.

Experimental Investigation and Optimization of Material Removal Rate and Tool Wear in the Machining of Aluminum-Boron Carbide (Al-B4C) Nanocomposite Using EDM Process

“…Nowadays, although metal matrix composites have more advantages, they are not widely used as their plastic counterparts. is paper presents getting precision machining obtained by smaller overcut dimensions of crater resulting in low MRR with less energy desirable [13,14]. Many combinations of metals, ceramics, and compounds are often used with matrices of low temperature alloys.…”

Study on Processing of Titanium Aluminide Alloy Using Electrical Discharge Machining

“…According to specialised literature the most important machining procedure of the Gamma Titanium Aluminide are Abrasive Waterjet Machining [2,3], Electrochemical Machining [4], Milling [5] and High Speed Milling [6], Electrical Discharge Machining [7], Wire Electrical Discharge Machining [8] and Grinding [9].…”

“…The severity and depth of the subsurface damage zone increased with an increase in abrasive grit size and depth of cut. Micro-EDM in dry conditions can be used for micro machining of γ-Titanium Aluminide [7]. The high heat and fire resistance property of these materials prevents electric arc issues during shot circuiting with low energy discharge and no deformation appear after machining.…”

“…The high heat and fire resistance property of these materials prevents electric arc issues during shot circuiting with low energy discharge and no deformation appear after machining. It was observed [7] that for given micro-EDM process parameters the crater depth formation by a single discharge in the absence of dielectric liquid (dry-micro-EDM) is relatively small, compared to machining in presence of dielectric oil and, in the same time the electrostatic force induced between the tool and work piece is considerably small in dry machining. In wire electrical discharge machining operations the most important parameters are pulse on time, pulse off time, peak current, wire tension, dielectric flow rate and servo reference voltage [8].…”