Ultrasonic vibration-assisted hard turning of AISI 52100 steel: comparative evaluation and modeling using dimensional analysis

Introduction. Precision machining of hard and brittle materials is difficult, which has led to the development of novel and sustainable techniques such as ultrasonic vibration-assisted turning (UVAT) for enhanced removal rates, surface quality, and tool life. The purpose of the work. Hard turning using cost-effective coated carbide tools instead of costly to operate ceramic and CBN inserts is still not widely accepted due to tool wear and machining limitations. A group of researchers attempted hard turning using carbide tools with different coatings, different cooling techniques, etc., to achieve better machinability. However, very few attempts were made by the researchers on ultrasonic vibration-assisted hard turning (UVAHT). Moreover, comparative evaluation of UVAHT using dimensional analysis is rarely reported in the open literature. The methods of investigation. With this view, this study comparatively evaluates the tool wear and power consumption during conventional turning (CT) and ultrasonic vibration-assisted hard turning (UVAHT) of AISI 52100 steel (62 HRC) using a PVD-coated TiAlSiN carbide tool. Experiments were performed with varying cutting speed, feed, and depth of cut while keeping vibration frequency and amplitude constant at 20 kHz and 20 µm, respectively. Further, a theoretical model was developed to predict the tool wear and power consumption using the concept of Dimensional analysis, i.e., the Buckingham Pi theorem considering the effect of cutting speed, frequency, and amplitude of vibrations at constant feed and depth of cut of 0.085 mm/rev and 0.4 mm, respectively. Dimensionless groups were created to reveal complex linkages and optimize machining conditions. Tool wear and power consumption were measured experimentally and statistically analyzed using the Buckingham Pi theorem. Results and Discussion. Using dimensional analysis, the research uncovers substantial insights into the UVAHT process. The results show that ultrasonic vibration parameters have a significant impact on tool wear and power consumption. Dimensionless groups provide a methodical foundation for refining machining conditions. The tool wear and the power consumption increase with the cutting speed, depth of cut, and feed. However, this effect is more significant in CT than UVAHT. The power consumption increases with the cutting speed, vibration frequency, and amplitude. However, the increase in the power consumption is more prominent when the cutting speed changes, followed by vibration frequency and amplitude. The flank wear increases with the cutting speed and vibration amplitude and decreases with the vibration frequency. This study contributes to a better understanding of the underlying dynamics of UVAHT, which will help to improve precision machining procedures for hard materials. The paper explores the practical significance of these discoveries for hard material precision machining.