Study of Machine Characteristics During Rotary EDM Machining using Tools Made of Aluminium Alloy 6061

Electro discharge machining (EDM) is an unconventional machining process that uses spark energy to remove material from the workpiece. EDM process is extensively being used in die/mould making industries, automobile industry, aerospace industry etc. for generating complex and intricate shape on hard material. Numbers of research works have been carried out using EDM process in order to improve the performance. Further, different variant of EDM process like dry EDM, orbital EDM, powder mixed EDM, ultrasonic assisted EDM and rotary EDM etc. have also been studied. Rotary EDM process is very promising process that helps to improve surface finish, overcut as well as out of roundness. In the present paper, a extensive review has been presented on rotary EDM process. Significance of several input parameters has been observed on output characteristics like overcut and out of roundness.

Comparison of Gas Assisted Hybrid EDM, Rotary EDM and Conventional EDM Processing of High Carbon High Chromium Die Steel

The high carbon high chromium die steel is most widely used in various industrial applications. However, effective machining of high carbon-chromium die steel is extremely difficult due to its high hardness and stiffness. In the present work, comparative analysis of Gas Assisted Hybrid EDM (GAHEDM), Rotary EDM (REDM), and Conventional EDM processes have been done with respect to process responses like electrode wear ratio (EWR), material removal rate (MRR), and surface roughness (SR). Experimentation has been done to the study influence of process factors like discharge current, pulse on time, duty cycle, tool rotation and discharge gas pressure on MRR, EWR and SR. Further, from a comparative study, it has been observed that high MRR, low EWR and low SR are obtained in GAHEDM process in comparison of REDM and EDM processes. Analysis of surface morphology reveals that the formation of recast layer and cracks on the surface are fewer in number on work piece machined by GAHEDM process with respect to specimen machined with REDM and EDM processes. The results show that the use of compressed helium gas in GHEDM process has a positive impact on the machining performance. This process may be used for industrial machining operation.