Due to their excellent properties, high-temperature alloys are widely used in critical aeronautics and astronautics components. However, their low thermal conductivity and high strength significantly increase machining difficulty. Minimum Quantity Lubrication (MQL) is a technology that can effectively improve the friction conditions at the tool-chip interface and reduce cutting temperature. Currently, MQL typically uses a single-component oil mist or adds nanoparticles to enhance cutting performance. To further improve the environmental friendliness and cutting performance of MQL oil mist, this study uses biodegradable vegetable oil as the base fluid, ethanol as an additive, and K403 cast nickel-based superalloy as the material of interest. The cutting performance under various conditions—dry cutting, supercritical carbon dioxide (ScCO 2 ), ScCO 2 -MQL, 0%E-MQL (MQL), 25%E-MQL, 50%E-MQL, 75%E-MQL, and 100%E-MQL (Ethanol)—is investigated. The impact of different ethanol contents on the cutting performance of vegetable oil-based MQL is analyzed. The results indicate that under the 75%E-MQL condition, significant advantages in cutting performance are observed during the turning of K403 cast nickel-based superalloy. Compared to dry cutting, cutting temperature is reduced by 44%, tool life increases nearly five times, cutting force is reduced, and surface quality is improved. Applying single cooling or lubrication methods could not significantly enhance cutting performance.
Jiao et al. (2026) studied this question.