Sustainability assessment of in-house developed environment-friendly hybrid techniques for turning Ti-6Al-4V

This work explores the machinability and sustainability of newly developed environment-friendly hybrid techniques for Ti-6Al-4V turning in terms of energy consumption, surface finish, and machining costs. Performances obtained under hybrid turning techniques namely cryogenic-ultrasonic assisted turning and cryogenic ultrasonic-minimum quantity lubrication assisted turning are compared with the cryogenic assisted turning technique. Energy consumption in the turning processes is assessed in terms of energy consumed by the machine tool, active cutting energy, and energy efficiency. Results show that active energy consumed by machine tool is decreased by up to 1.8-3.6% using hybrid turning techniques as compared to cryogenic assisted turning technique. An increase in energy efficiency values is observed at higher levels of input process parameters using all three turning techniques. Average surface roughness values are decreased by up to 32%-42% using hybrid turning techniques as compared to the cryogenic assisted turning technique. A sustainability index, i.e., relative sustain ability of process is used to quantify the sustainability of the turning operations. The results show a significant role of newly developed hybrid technologies in the machining industry to meet energy-saving and sustainability goals without compromising product quality. (C) 2020 Elsevier B.V. All rights reserved