Experimental investigation on machining characteristics of titanium processed using electrolyte sonicated µ-ECDM system

Abstract

Micromachining of difficult-to-machine materials is of prime focus nowadays. One such material is Titanium, which has numerous applications in aerospace, chemical, and biomedical industries. The micromachining of Titanium has become the need of the day because of its exhilarating properties. This investigation employs a tailor-made electrolyte sonicated micro-electrochemical discharge machining (ES-µ-ECDM) system to generate microholes in a commercially pure titanium plate with a thickness of 1000 µm. The machining chamber is the ultrasonication unit (36 kHz) with process parameters voltage (V), concentration (wt%), and duty factor (DF) chosen at three levels. The FCC-RSM-based DOE is selected for experimentation to study the machining characteristics like material removal rate, overcut, and circularity. Through holes were achieved at parameters of 80 V, 25 wt%, and 60% DF and 80 V, 30 wt%, and 50% DF. The incorporation of ultrasonication into the system enhanced electrolyte replenishment and evacuation of the debris at the machining vicinity. The assistance technique improved the gas film stabilization around the tool enabling uniform machining. The multi-response optimization is performed using the MOJAYA algorithm to obtain Pareto optimal solutions, and the MADM (R-method) is employed to obtain the optimal parameter. The optimal parameter was found to be 69 V, 30 wt%, and 50% DF, at which the machined microhole was found to have a circularity of 0.9615 with minimal surface defects.