PARAMETRIC INVESTIGATION IN ULTRASONIC MICRO MACHINING

Abstract

In past decades rapid developments have been made in the field of biotechnology, electronics and communication and optics. This research has been applied on micro fluidics and micro electromechanical systems (MEMS) such as micro heat exchangers, micro coolers, micro biochips and micro fuel cells. All these micro fluidics system requires micro channels for the flow of fluids and gases. in these micro fluidic devices micro channels play vital role for transportation of fluid within very small size area. Micro channels can be made from various materials such as Silicon, Nickel, Polycarbonate, Polyamide, Fused silica, Stainless steel, Copper, Aluminium, Brass and glass etc. machining of these materials is a dreadful task. Silicon has wide range of applications in the field of micro devices but in many applications silicon can't be considered as suitable material. Glass consists of properties like transparency, chemical inertness, and mechanical robustness. So glass is a satisfactory replacement for silicon in micro fluidic, micro optical and micro electromechanical systems (MEMS). Some vital applications of glass are pressure sensors, Bio-MEMS devices which are enabled by lab-on chip and micro fluidics technologies. Rotary Ultrasonic Machining (RUM) is satisfactory process for machining above mentioned materials. It is a hybrid machining process of conventional grinding and ultrasonic machining. To generate miniaturized parts i.e. micro channels, micro holes and 3D cavities on above mentioned materials require downscaling of RUM. The objective of this thesis is to develop a set up for Rotary Ultrasonic Micro Machining and fabricate micro channels on glass by the developed set up. These micro channels are developed when subjected to change in various parameters such as abrasive size, abrasive slurry concentration, feed, spindle speed and amplitude of vibrations. The quality characteristics measured are material removal rate (MRR) and surface roughness. Taguchi method is applied to find out optimal set of parameters.