| Abstract: | In the current research, rotary ultrasonic machining was used to drill holes in quartz material. The effect of different RUM parameters namely tool feed rate, tool rotational speed and ultrasonic power on material removal rate and surface roughness has been studied experimentally. The response surface methodology with central composite design has been used to design the experiments. From the desirability approach, the optimum setting of the rotary ultrasonic machining parameters was found to be the tool rotational speed of 4968 rpm, feed rate of 0.55 mm/min, and ultrasonic power of 80% for achieving the maximum MRR of 0.2135 mm3/s and minimum SR of 0.3685 μm. Microstructure analysis of the machined surface was performed by using scanning electron microscopy in order to study the mechanisms of material removal under the different settings of RUM parameters. It was observed that at very low feed (0.08 mm/min) and high rpm (5681) the material is predominantly removed by plastic deformation whereas at high feed (0.92 mm/min) and low rpm (2318) the material is removed by brittle fracture. |
