Determination of Material Removal Rate and Radial Overcut in Electro Discharge Machining of AISI 304 Using Dimensional Analysis

摘要

Electro discharge machining (EDM) is a most commonly used machining process among all the non-conventional machining process which removes materials via electrical and thermal energy. The primary goal of EDM is to get more material removal rate (MRR) with lower radial overcut (ROC). Normally, the responses are predicted using empirical models which are limited to only machining parameters and they do not consider the effects of work material properties on the process performance. Therefore in this study, a model has been developed including machining parameter as well as thermo-physical property of work material. In this investigation, a semi-empirical model has been established for the material removal rate (MRR) and radial overcut (ROC) by adopting the dimensional analysis technique. Dimensional analysis is a technique of dimensions and a mathematical technique that deals with the physical quantities concerned with the experiments to formulate a model for the response in terms of response control parameters as well as some physical properties of the materials. Buckingham's π theorem is a main theorem in dimensional analysis and it is a signification of Rayleigh's method of dimensional analysis. The theory is applied to gather each and every variable presenting the problem in a number of the dimensionless products. For this study, the thermo-physical properties viz. density, thermal conductivity and coefficient of thermal expansion and machining parameters like peak current, pulse on time, gap voltage and duty cycle are considered as input factor. AISI 304 stainless steel used as work material and Tungsten carbide is used as tool material for this investigation.