Effect of micro-EDM machining parameters on the accuracy of micro hole drilling in Zr-based metallic glass

Abstract

Micro drilling of metallic glass is a technologically important research due to recent development of metallic glass and their technological niche applications in field of micro nozzles, micro-electro mechanical systems (MEMS) and bio-implants. Micro drilling of metallic glass is a challenging work because of in situ crystallization of resultant workpiece due to localized high heat generation during machining. However, micro-electrical discharge machining (Micro-EDM) eludes the limitations of conventional machining methods and offers precise machining of metallic glass with good surface properties. Micro-EDM machining parameters exerts a big influence on the machined features and their surface properties. A study of effect of micro-EDM machining parameters on machined geometry's features and optimization of machining parameters for accurate machining of metallic glasses are very essential owing to the recent advancements in the applicability of Micro-EDM for processing of metallic glass parts. In present work micro-EDM is used for precision drilling of micro holes in metallic glasses. The levels of input micro-EDM machining parameters such as capacitance, voltage, tool revolutions per minutes (RPM) for optimum accuracy of micro holes and minimum machining time are identified. Resultant of present work culminated to the establishment of micro holes with exceptional accuracy using micro-EDM. The tool RPM is found to be a key parameter for increasing hole accuracy as well as reducing machining time. Outcome of present work may pave application of metallic glasses products based on precision engineering.