Formulation and performance evaluation of a novel coconut oil–based metalworking fluid

ABSTRACT

Metalworking fluid (MWF) supplies a film of lubricant to abate friction, acts as a cooling media to rebate induced heat, and prevents metal pick-ups by flushing away the chips. Hence a liquid used as a cutting fluid reduces wear on the tool, reduces the energy consumption, and produces a better surface quality on the work piece. This paper describes the formulation of a novel water-soluble MWF and its performance evaluation during straight turning and end milling experiments carried out with AISI 304 stainless steel, mild steel, and cast iron as work piece materials. The MWF was prepared by mixing water with white coconut oil as the base oil and food-grade additives as surfactants. Viscosity, pH value, and biodegradability were measured and compared with a commercially available non-vegetable oil–based MWF. The surface roughness and tool surface temperature were measured throughout the machining experiments, and better performances were observed with the coconut oil–based MWF. Tool tip geometry and flank wear for straight turning machining operation were identified by observing scanning electron microscope (SEM) images.

KEYWORDS:

• Biodegradability
• coconut
• emulsion
• flank
• fluid
• metalworking
• milling
• oil
• roughness
• turning
• wear

Acknowledgments

Authors express gratitude to G.L. Damayantha and L.N. Kalansooriya for all the support extended for the experimental work presented herein.