Comprehensive experimental analysis and sustainability assessment of machining Nimonic 90 using ultrasonic-assisted turning facility

Many techniques have been developed to improve the machinability of aeronautical materials titanium and nickel-based alloys such as ultrasonic-assisted turning, laser-assisted turning, and cryogenic-assisted turning. This collaborative scientific investigation presents the steps taken to gain insight into the phenomena of machining Nimonic 90 (a nickel-based alloy) alloy using ultrasonically assisted turning. The cutting speed, feed rate, depth of cut, and frequency are taken as input parameters and average surface roughness (R_a), power consumption (P), and chip formation are considered as output parameters. The experiments are carried out with the full factorial design. The UAT (ultrasonically assisted turning) process gives a significant improvement in average surface roughness and power consumption because of the intermittent cutting action of the cutting tool. UAT process shows a 70–80% reduction in average surface roughness (R_a) and a 6–15% reduction in power consumption as compared with CT (conventional turning) process. Ultrasonically assisted turning also resulted in the thin and smoother chips as compared with CT process which helps to achieve a more superior machining effect. Finite element modeling shows that the quasi-static nature of the stress induced in the UAT process leads to lower force and ultimately lower power generation. Moreover, a sustainability assessment model is implemented to investigate the effect of UAT in terms of machining performance as well as sustainability effectiveness in a single integrated approach. The novelty of this work lies in providing an integrated concept that combines experimental analysis and sustainability assessment when using ultrasonic vibrational energy during turning of Nimonic 90.