Study on Multi-objects Optimization in EDM with Nickel Coated Electrode using Taguchi-AHP-Topsis

To improve productivity and quality of machining process using EDM, a lot of electrodes such as coated and alloy electrodes has been applied. Study on multi-objects optimization in EDM with coated electrode will increase number of application of this field into practice. In this study, material removal rate (MRR) and surface roughness (SR) in EDM using nickel coated aluminium electrode were optimized simultaneously using Taguchi-AHP-Topsis methods. Technological parameters including Peak Current (I), Gap Voltage (U) and pulse on time (Ton) were investigated. Titanium alloy (Ti-6Al-4V) was selected as workpiece in experimental process. The results show that combination among Taguchi-AHP-Topsis methods is suitable to solve multi-objects optimization in EDM. The optimized technological parameters are I = 30 A, Ton = 500 µs, U = 50 V and optimized quality criterias are MRR = 0.17 mm3/min and SR = 8.76 µm.