ABSTRACT
Using of natural oils in machining process for lubrication/cooling purposes represents an increasing trend nowadays because of their good properties from the environmental point of view, thermal and oxidative stability in comparison with conventional cutting fluids. All of mineral oils have harmful effect on human beings, for that; environmental issues during machining have led to looking for safe and efficient cutting fluids. The objective of this work is to investigate the effect of vegetable oils based emulsion (VOBE) on the surface roughness during turning process of aluminum 6061 alloy in comparison with traditional cutting fluids mineral oils based emulsion (MOBE), that known commercially as (ecool mk-3).  Corn, olive and coconut oils were proposed as vegetable oils based emulsion for lubrication/cooling during turning process under different conditions of cutting speed and feed as well as the concentration of oil in lubricating emulsion. Digital Surface Roughness Tester (TR-Y-SRT-6210S) was used for surface roughness (Ra) measurements of the machined aluminum bars. The results show good performance for vegetable based emulsion oils in turning process as lubricant medium compared to dry cutting or using traditional lubricants based on mineral oils. Coconut oil based emulsion shows significant effect on reduction of surface roughness of machined parts as well as good healthy impact.