A review on sustainable machining: Technological advancements, health and safety considerations, and related environmental impacts

The evolution of advanced engineering materials and high-speed cutting techniques has emphasized the critical role of cutting fluids (CFs) in machining processes to meet sustainability requirements. Cutting fluids application offers several key benefits, including temperature reduction during cutting, decreased friction between the workpiece/chip and tool, extended tool lifespan, enhanced machining efficiency, and boosted surface finish. These positive outcomes are primarily attributed to the core functions of cutting fluid, namely lubrication, cooling, cleaning, and corrosion protection. However, they have serious disadvantages such as posing risks to ecosystems and human health as well as high disposal costs. Despite these disadvantages, ongoing research and development efforts are focused on improving the environmental sustainability, health and safety, and performance of metal cutting fluids through the use of green biodegradable oils, developing advanced recycling technologies, and the use of efficient application methods such as high-pressure cooling and minimum quantity lubrication (MQL). This review paper sheds light on sustainable machining technologies that are utilized to minimize the environmental impacts of conventional cutting fluids. Different types of CFs including their benefits and role in cutting operations are also introduced. Finally, sustainable assessment including economical, environmental, and social aspects of green machining technologies is discussed.