Role of cutting fluids under minimum quantity lubrication: An experimental investigation of chip thickness

Abstract

Machining plays an important role in the industrial process of the economy through the way it contributes around 5% of the country’s total economy. Various shapes of final products from raw material are processed by machining, which in turn leads to the formation of chips. Chip is an important aspect should be studied to know in-depth about machining conditions. Parameters to be explored by chip investigation are mainly include; specific energy, interfaces between chip and tool and work material behaviour during machining. AISI 4340 hardened steel material is used for chip investigation in present experimentation. Some of the adverse common issues with this steel machining are high temperature, extreme tool wear and sudden tool failure; which can be eliminated using sustainable machining practices such as application of Minimum Quantity Lubrication (MQL) with bio cutting fluids. This paper emphasizes upon the experimental investigations of chip thickness to reveal the various relevant parameters such as shear angle, specific energy required for machining and cutting force. Better performance of coconut oil was observed in terms of minimum chip thickness and maximum shear angle at higher cutting speed, when compared it with canola oil and soybean oil. For further investigation and study; results of bio cutting fluids are compared with synthetic oil and dry machining conditions. Entire experimentation was carried out under MQL environment except for one experimental observation in the dry state for comparison.