Performance of commercial and palm oil lubricants in turning FCD700 ductile cast iron using carbide tools

In a machining operation, cutting fluids are widely used as coolants to reduce the effects of heat, and also as lubricants to reduce the interface friction between the tool chip and tool workpiece. This paper presents the performance of both inorganic commercial lubricants and environmental friendly organic palm oil based lubricants, when turning FCD700 cast iron using carbide tool. Two sets of turning parameters were tested: i) cutting speed of 120 m/min, feed rate of 0.3 mm/rev, and depth of cut of 0.6 mm, and ii) cutting speed of 220 m/min, feed rate of 0.2 mm/rev, and depth of cut of 2 mm. The results show that for both turning conditions, the tool life for the commercial lubricant was longer than the palm oil based lubricant by more than double. Better surface roughness was obtained using the palm oil based lubricant by about 1?m, due to the oxygen in vegetable oil compound, which creates a stronger bonded layer of lubricant on the metal surface. The Ra accuracy can also be affected by the dirt or imperfection of the machined surface produced when the cutting tool begins to wear out