A Study on Optimization Techniques of Electro Discharge Machining

Abstract

The technique of optimization is a mathematical method for calculating the maximum and minimum value of a function f(x), which is subject to certain constraints. Optimization is the expression, under the given circumstance, of obtaining the best mix of outcomes. No specific methods are available to deal with all numerical and mathematical issues. So different types of techniques for dealing with different kinds of issues have been introduced. The optimization technique is most widely used in Electro Discharge Machining (EDM) to find the best combination of input parameters (such as current, voltage, pulse on time, pulse off time, etc.) for the desired output parameters (such as material removal rate, surface roughness, tool wear rate, etc.). This method usually only applies to conductive materials (such as silver, copper, aluminium, brass, bronze, etc.). Electricity can flow through the conductive materials for conductivity. Once dielectric fluid (acts as a semiconductor and flushing agent to clean and remove eroded debris from the region of the spark gap, such as kerosene, EDM oil, and deionized water) flows, the workpiece is released metal ions, and the tool is released electrons. Therefore, a spark is formed between the tool and workpiece and induced temperature of 8000–12000 ℃, and due to this spark energy, the material is removed from the substrate. The maximum MRR (Material removal rate), minimum TWR (Tool wear rate) and SR (Surface roughness) are critical for the optimization technique. In this study, different types of optimization techniques are defined for EDM machining purposes based on their uses.