Micro electric discharge milling process performance: An experimental investigation

Micro electric discharge milling (μED-milling) process is gaining lot of interest in the area of microfabrication specifically for hard to machine materials. Any complex shape can be generated with a controlled motion of cylindrical tool in a predefined path similar to conventional micromilling. In this method the material removal mechanism in tool and workpiece is complex and requires a detail study of the process parameters. Parameters such as tool rotation speed, feed rate and aspect ratio (AR) can play a vital role in μED-milling process along with the fundamental parameter such as energy. This research work aims to provide exhaustive study of parameters on material removal rate (MRR) and tool wear rate (TWR) by conducting general factorial experiments. A new method is proposed to measure the volume of material eroded from workpiece and tool with an aid of design software. The experimental result shows that the parameters have individual and combined effect on MRR and TWR. Among the parameters, tool rotation speed has a significant function in flushing away the debris to ensure stable discharge. Detailed surface morphology of the machined features has also been analyzed using scanning electron microscope (SEM). A regression analysis was carried out to establish models for MRR and TWR as a function of process parameters.

[1]  I. Puertas,et al.  Analysis of the influence of EDM parameters on surface quality, MRR and EW of WC–Co , 2004 .

[2]  Mu-Tian Yan,et al.  A study on electrode wear sensing and compensation in Micro-EDM using machine vision system , 2009 .

[3]  M. Bayramoglu,et al.  Systematic investigation on the use of cylindrical tools for the production of 3D complex shapes on CNC EDM machines , 1994 .

[4]  P. Dario,et al.  Non-traditional technologies for microfabrication , 1995 .

[5]  Ming Zhou,et al.  High-speed EDM milling with moving electric arcs , 2009 .

[6]  W. S. Lau,et al.  Spark erosion with ultrasonic frequency , 1997 .

[7]  Takeshi Kishinami,et al.  Development of Numerical Contouring Control Electric Discharge Machining (NCC-EDM) , 1986 .

[8]  P. T. Tang,et al.  Comparison between microfabrication technologies for metal tooling , 2006 .

[9]  Muhammad Ekhlasur Rahman,et al.  Tool-based nanofinishing and micromachining , 2007 .

[10]  Xiaoping Li,et al.  Study of the surface integrity of the machined workpiece in the EDM of tungsten carbide , 2003 .

[11]  Takahisa Masuzawa,et al.  Improved Jet Flushing for EDM , 1992 .

[12]  Kamlakar P Rajurkar,et al.  Micro and Nano Machining by Electro-Physical and Chemical Processes , 2006 .

[13]  Songlin Ding,et al.  CNC electrical discharge rough machining of turbine blades , 2006 .

[14]  Y. Liu,et al.  Effect of machining fluid on the process performance of electric discharge milling of insulating Al2O3 ceramic , 2008 .

[15]  Philip Koshy,et al.  Electrical discharge milling with oblong tools , 2009 .

[16]  Sachin Maheshwari,et al.  Some investigations into the electric discharge machining of hardened tool steel using different electrode materials , 2004 .

[17]  Kristian L. Aas,et al.  Performance of two graphite electrode qualities in EDM of seal slots in a jet engine turbine vane , 2004 .

[18]  Yoke San Wong,et al.  Development and evaluation of an on-machine optical measurement device , 2007 .

[19]  Nobuhiro Nakajima,et al.  High Speed 3D Milling by Dry EDM , 2003 .

[20]  J. S. Soni Microanalysis of debris formed during rotary EDM of titanium alloy (Ti 6A1 4V) and die steel (T 215 Cr12) , 1994 .

[21]  T. Kaneko,et al.  Three-dimensional numerically controlled contouring by electric discharge machining with compensation for the deformation of cylindrical tool electrodes , 1988 .

[22]  Jun Ni,et al.  Experimental Study of the Dry and Near-Dry Electrical Discharge Milling Processes , 2008 .

[23]  H. Singh,et al.  Improvements in performance of EDM-A review , 2008, IEEE SoutheastCon 2008.