Title: Investigation of single pulse discharge on silicon: crater and plasma characteristics
Authors: S. Kanmani Subbu; S. Dhamodaran; J. Ramkumar
Addresses: Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Uttar Pradesh, Kanpur – 208016, India. ' Department of Physics, Indian Institute of Technology Kanpur, Uttar Pradesh, Kanpur – 208016, India; Department of Nano Engineering, University of California San Diego, 9500 Gilman Drive, La Jolla, CA-92093-0448, USA. ' Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Uttar Pradesh, Kanpur – 208016, India
Abstract: Micro electric discharge machining (µ-EDM) process is being used to machine complex shapes on silicon. In specific, dry-µ-EDM can be used to process assembled or semi assembled silicon products. However, there is lack of investigation on the effect of single pulse discharge machining and its plasma characteristics on silicon. Hence, in this paper we investigate the crater and plasma characteristics of single discharge for various conditions such as different electrode diameters and different energy conditions (fixed voltage with varying capacitance and vice-versa). The plasma temperature and electron density have been calculated by line pair method and modified Saha equation respectively. The values are mapped into the plasma classification plot based on log scale of plasma temperature and electron density and realised that at µ-scale EDM plasma was found to be ideal up to 50 mJ energy and tends to become weakly non-ideal plasma for 98 mJ energy. Also from the influence of energy on plasma characteristics it is understood that electron density also plays a major role along with the plasma temperature.
Keywords: silicon; single pulse discharge; craters; plasma temperature; electron density; dry machining; electrical discharge machining; micro EDM; electro-discharge machining.
International Journal of Mechatronics and Manufacturing Systems, 2012 Vol.5 No.5/6, pp.455 - 469
Received: 27 Aug 2011
Accepted: 10 Apr 2012
Published online: 21 Aug 2014 *