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Electrodeposition of copper was done with different molecular weight (MW) polyethylene glycol (PEG) as an additive in the plating bath. The adsorbed layer formed of PEG and chloride ion (Cl − ) in the presence of copper ions has a definite role in controlling the deposition mechanism and the coating characteristics. The adsorption behaviour and suppressor nature of PEG with different MW (200-20000) on the physicochemical and the surface morphological features of the copper deposit were characterized. The results reveal that depending on the adsorption capacity of the intermediate complex, the deposit properties show gradation. There is a range of morphology with particular grain structure for different MW PEG addition. Grain size and the roughness decreased with increase in PEG MW. The concentration of Cl − ion in the plating bath is also significant in determining the deposit mechanism of the bath as revealed from the shift in cathodic potential. The adsorbing power of the complex depends not only on PEG MW but also on Cl − ion concentration. XRD analysis of the copper deposit obtained with low MW PEG showed (220) as the major plane and with high MW PEG the prominent orientation was (111) and (200).

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Wire electrical discharge turning (WEDT) is a non-conventional machining process, which was developed to machine cylindrical components on difficult-to-machine, but electrically conductive materials with high precision. In the present work, roundness, cylindricity and areal surface roughness of the parts created by WEDT process are investigated. Inconel 825 was the material chosen for the present study. The main objective of this study is to identify the optimum process parameters required to obtain improved geometry of the turned components with respect to roundness, cylindricity and areal surface roughness. The effects of machining parameters in WEDT process on the output responses are studied using experiments based on Box-Behnken design. ANOVA has been performed to study the effect of process parameters on the output responses. A novel optimization approach is used to identify the optimum parameters for each response. Teaching learningbased optimization (TLBO) is used to optimize the process, considering the three output responses in order to improve the quality of the turned products. Validation experiments were conducted, and the predicted results were verified. It is observed that the roundness, cylindricity and areal surface roughness of components machined with WEDT process obtained from TLBO technique and validation experiments are in close agreement. The surface morphology of the samples having maximum and minimum Sa value was studied using SEM micrographs. Finally, a microelectrode of 185 µm diameter and 4 mm length was successfully fabricated with multiple cut strategy using the WEDT setup in order to demonstrate the process capability.