A review of accuracy enhancement in microdrilling operations

Micromachining, which is a manufacturing technique to produce miniature parts, carries with it the major factor of precision in machining. The various processes of micromachining, be it contact or non contact methods, have their own merits and demerits. However, producing microstructures such as micro-holes which find widespread application in highly sensitive products such as automotive fuel injection nozzles, watches, medical electronics, and camera parts requires a high degree of accuracy in its profile parameters. Microdrilling, the most ideal micromachining process to generate micro-holes, can generate deeper holes with better straightness, better roundness, and smoother surfaces. This paper focuses on all existing microdrilling techniques that have been used in producing micro-holes along with the various strategies that have been adapted to improve the accuracy in hole dimensioning and its shape. The review of the various accuracy-related microdrilling operations will enable one to understand better the need for accuracy in micro-hole production, the various microdrilling techniques, and most essentially how the accuracy has been improved with technology advancement and better research. It also provides an overview which will help further propagation and implementation of more techniques to further enhance the accuracy of microdrilling operations, bringing about precise components of micromachining.