Parametric analysis of fabrication of through micro holes on titanium by maskless electrochemical micromachining

Abstract

Machining of micro features on titanium is a complex task due to its natural physical and chemical properties. Electrochemical micromachining (EMM) presents several advantages, such as minimum or no tool wear, stress-free machining with greater surface finish. This paper demonstrated successful fabrication of micro feature, i.e., through micro holes on pure commercial titanium with the help of maskless electrochemical micromachining process. Influence of various EMM process parameters, i.e., machining voltage, pulse frequency, duty ratio, and micro tool feed rate on machining accuracy in terms of radial overcut and conicity of micro hole as well as material removal rate (MRR), has been investigated to establish suitable process parameters for through micro hole generation. Surface quality of machined micro holes with respect to EMM process parameters was also investigated. Outcomes of this experimental investigation ensure fabrication of through micro holes with minimum overcut and taper angle. Machining voltage of 8 V, pulse frequency of 200 kHz, and micro tool feed rate of 0.6 μm/s with lower duty ratio are proved to be major influencing parameters. Surface roughness of 0.09 μm has been achieved with most suitable process parameters. In situ fabricated disk micro tool has been utilized to enhance machining accuracy. The study presented in this article can be a potential application for generation of various other micro features on pure commercial titanium which will find potential applications in microneedles, drug delivery systems, and features for various BioMEMS and engineering applications.