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Owing to the desirable properties of vegetable oils as cutting fluids, an attempt is made to explore the potentiality of plentifully available vegetable oils as a cutting fluid for turning AA 6061. Two nonedible vegetable oils, Jatropha and Pongamia, in their chemically modified (epoxidized) versions are used as straight cutting fluids. Cutting fluids are introduced to the machining zone with the aid of Minimal Quantity Lubrication (MQL) method. Taguchi's technique of orthogonal arrays is used to develop an effective design of experiments. The results obtained under epoxidized versions of Jatropha and Pongamia oils are compared with the results of mineral oil in terms of cutting forces and surface roughness. Experimental observations and statistical analysis show that, compared to mineral oil, the modified versions of vegetable oil-based cutting fluids are more effective in reducing the cutting forces and increasing surface finish. It is also observed that the modified Pongamia oil showed lesser flank wear compared to the other two tested oils.

The friction and wear tests on AISI 1040 are carried out under raw, modified versions of two nonedible vegetable oils Pongam (Pongamia pinnata) and Jatropha (Jatropha curcas) and also commercially available mineral oil using a pin-on-disc tribometer for various sliding distances and loads. A significant drop in friction and wear for AISI 1040 is observed under Pongam and Jatropha raw oil compared to mineral oil, for the complete tested sliding distance and load, increasing the potential of vegetable oil for tribological applications. Stribeck curves are also drawn to understand the regimes of lubrication. Both the vegetable oils showed a clear reduction in the boundary lubrication regimes, leading to an early start of full film lubrication.

The raw and modified versions of two nonedible vegetable oils, Pongam (Pogammia pinnata) and Jatropha (Jatropha curcas), and a commercially available branded mineral oil are used as straight cutting fluids for turning AA 6061 to assess cutting forces. Minimum quantity lubrication is utilized for the supply of cutting fluids. Cutting and thrust forces are measured. Cutting power is determined for various cutting speeds, depths of cut, and feed rates. Also, drilling is performed on the material to understand the material removal rate (MRR) under these oils. The performances of vegetable oils are compared to mineral oil. A noticeable reduction in cutting forces is observed under the Jatropha family of oils compared to mineral oil. Further, better material removal rate is seen under both the vegetable oils and their versions compared to under petroleum oil for the range of thrust forces.

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