PERFORMANCE EVALUATION OF CUTTING FLUIDS MADE FROM BIO-DEGRADABLE VEGETABLE OILS IN MACHINING OF MILD STEEL

Abstract: Three vegetable oils, palm oil, shea butter, and groundnut oil, were investigated for use as lubricants in the orthogonal turning of mild steel. The cutting speed was varied while the depth of cut and feed was kept constant; the surface finish was determined using a roughness checker, and the interface temperature was measured using a k-type thermocouple. Tool life and coefficient of friction were determined. Results show improved tool life and good surface finish were obtained at low and medium cutting speeds. Findings show the satisfactory performance of groundnut oil with chip compression of 0.83 at the speed of 300 rpm and that of the shear butter with a maximum temperature of 62oC within the speed range. The cooling effect of the vegetable oils compared favourably with that of the standard soluble oil. The order of performance of the oils was palm oil, shear butter, and groundnut oil, which decreased in order, a performance attributed to their oiliness. The result of this work can be used to source new cutting fluids in cutting operations.