Multi-response optimisation of micro-EDM drilling of Ti-5.6Al-3.6V using grey-fuzzy logic based approach

Titanium alloy is used to make numerous small parts and components due to excellent mechanical and engineering properties. The goal of this study is to see how input parameters for micro-electric discharge machining (EDM) affect the production of micro-holes in titanium alloy. Response surface methodology (RSM)-based central composite design (CCD) was used to design the experiments, using current (Ip), pulse-on-time (Ton), and pulse-off-time (Toff) as input parameters; and drill rate (DR) and tool wear ratio (TWR) as measuring performance. The grey-fuzzy integrated technique was utilised to discover the best parameter settings for the EDM process and to optimise the responses. Grey fuzzy reasoning grade is determined using grey relational analysis combined with a fuzzy-based technique. The optimal setting of parameters is found to be Ip = 5 A, Ton = 70 μs, Toff = 60 μs. For multi-objective responses, ANOVA study revealed that Ton is the most influential parameter, followed by Ip. The optimised result and experimental result of a repeated experiment are compared. The results reveal that DR is increased from 0.4345 to 0.5259 mm/s and TWR is decreased from 0.250 to 0.208 for the optimised parameters over the initial parameters of the EDM.