Investigation of Ionic Liquids as Novel Metalworking Fluids during Minimum Quantity Lubrication Machining of a Plain Carbon Steel

Metalworking fluids are a major cause of health hazards for operators apart from being sources of environmental pollution, thus necessitating research in dry and minimum quantity lubrication (MQL) machining. Ionic liquids are a relatively new family of environment-friendly chemicals that have significant potential to be employed as lubricants in MQL machining. This paper presents the results of preliminary studies in which three ionic liquids based on the 1-methyl 3-butylimidazolium cation were applied as additives to vegetable oil in MQL machining of AISI 1045 steel under interrupted orthogonal cutting conditions. The results show that the presence of even minute quantities of ionic liquids can significantly affect the machining process through reduction in cutting forces and surface roughness of the machined workpiece, as compared to dry cutting, conventional flood-cooled cutting, and MQL machining with neat vegetable oil.