Improvement of form accuracy in hybrid machining of microstructures

Micromachining is gaining popularity due to recent advancements in Micro Electro Mechanical Systems. Using conventional micromachining, it is relatively difficult to produce moving components in the order of microns. In this study, an attempt is made to fabricate microstructures using a combination of turning and electrodischarge machining (EDM). Several sets of experiments have been performed to study the characteristics of the hybrid machining process. From the experiments, it has been observed that a higher form of accuracy could be obtained by integrating the on-machine fabrication of the tool and by subsequently using the same tool for EDM. The main cause of the form error is due to the deflection of the shaft during turning. Hence, an attempt is made to observe the deflection of the shaft using a deflection sensor. The influence of micro-EDM parameters such as feed rate, discharge circuits, and gap control parameters on material removal rate and tool wear is also discussed in this study.