Rotary ultrasonic machining of macor ceramic: An experimental investigation and microstructure analysis

Abstract

ABSTRACTMacor ceramic has been well recognized as a classic engineering material that possesses wide industrial usage owing to its excellent and versatile properties. However, its fruitful and productive processing is still unanswered. The present article attempts to experimentally investigate the influence of numerous process variables on machining characteristics in rotary ultrasonic machining of macor ceramic. The impact of different input factors, namely spindle speed, feed rate, coolant pressure, and ultrasonic power, has been evaluated on the process responses of interest, i.e., surface roughness (SR) and chipping thickness (CT). The experiments are designed by utilizing response surface methodology (RSM) through a central composite rotatable design. The variance analysis test was performed with a view to observe the significance of the considered parameters. Microstructure analysis of the machined samples revealed and confirmed the presence of dominating brittle fracture that caused the removal of material along with a slight plastic deformation of the work surface. The multi-response optimization of machining responses was carried out by utilizing the desirability approach. At optimized parametric setting, the obtained experimental values for SR and CT were found to be 0.523 µm and 0.156 mm, respectively.