Machinability study of high speed steel for focused ion beam (FIB) milling process – An experimental investigation at micron/nano scale

• FIB milling of high speed steel (HSS).
• Study of machinability aspects of HSS for FIB milling.
• Optimization of FIB milling process parameters for minimization of surface roughness and maximization of material removal rate.

Nowadays the attention is focused on machining of non-silicon materials for miniaturized devices. High speed steel (HSS) is a non-silicon tool material, which is used in metal cutting applications as well as in micro-medical applications. Focused ion beam (FIB) milling process is highly suited for the fabrication of micro tools and other micro devices manufactured from HSS material. This study investigates the machinability aspects of HSS for FIB milling process. Beam current, extraction voltage, angle of incidence, dwell time and percentage overlap between beam diameters are the FIB process parameters, which have been analyzed experimentally to optimize FIB milling process for maximum material removal rate and minimum surface roughness. Beam current is found as the most significant parameter for controlling the material removal rate and surface roughness.