Effect of minimum quantity of lubricant (MQL) on tool wear and product quality in machining steel by coated carbide insert

Abstract

The concepl of Minimum QU811tity Lubrication (Mal) sometimes referred to as near dl)' lubrication or micro lubrication has been advocated since a decade ago as a me8rlS of addressing the issue of environmer'llal troublesome. Minimum Quantity Lubrication mentions to the use of cutting fluid of only a Iiille amount usually of a flow rate of 50 to 500 ml/hour-which is about tllree to four orders of scale lower than the amount commonly used in flood cooling condition, lor example, up to 10 liters of fluid can be supplied per minute. Saving lubricant costs and tool Iworkplece/machine cleaning cycle time the minimization of cutting fluid also leads to economical benefits. A number of studies have showr'l that MQL machining can show saliSfactory performance in praclical machining operations. But, there has been lillie Investigation of the cutting fluids to be used in MQL machining. In this regard the proposed research work has been earned out with a view to study the effects of Minimum Quantity lubrication (MQl) by water soiuble cutting fluid on the cutting performance of medium carbon steei, as compared to completely dry and wet machining in terms of tool wear reduction, tooi iife increment and machined surface mtegrlty, Based on the procesS parameters (speeds, feeds and depth of cut) an approach has also been performed to recognize the apt MQL nozzle position for better coohng aellon, In the study, the minimum quantity iubrication will be provided with a spray of air and water soluble cutting fluid. Significant progress xii has been made In dry and semidry machining recently, and Minimum Quantity Lubrication (MQL) machining in particular has been accepted as a successful semi-dry application because of its environmentally friendly characteristics. " Compared to the dry or wet machining, MOL machining performed much better-quality, mainly due to considerable in cutting zone temperature enabling favorable chip formation and chip-tooi interaction, It also provides substantial reduction in tool wear, which augment the toci life, and surface finish. Moreover, it provides environment friendliness (maintaining neat, clean and dry working area and improves the machinability characteristics.