Effect of Minimum Quantity Lubrication (MQL) Method on Machining Characteristics for Ductile Substrates: A Future Direction

In today’s manufacturing industries, the machining stage is the most critical one. At some point throughout their manufacture, most of the items need to be machined. This inclusive review is to investigate the influence of machining settings: dry, flood, and minimum quantity lubrication (MQL) on machining characteristics of desired substrates by milling process. The machining factors-for instance, cutting speed, feed, lubricant type, nozzle elevation angle, and others-are elaborated to get the best outcome performance characteristics, for example, material removal rate, surface roughness, and surface texture. Many studies show some significant influence of the MQL technique on output machining characteristics. An experimental study reported that using cutting speed (300 m/min), feed (0.1, 0.2 mm/rev), and MQL flow rate (10 ml/hr) input parameters, the MQL method resulted in a smoother surface and fewer chips. In another comparative study between MQL and dry milling investigation, at a flow rate of 40 ml/hr, the MQL approach improved the surface finish values by 8.8% and 22.5% for flow rates of 20 ml/hr and 40 ml/hr, respectively. It was reported that the MQL process produced better surface finishes and fewer chip formations. Finally, it is stated that the MQL technique would be a cutting-edge machining technique, and it can be explored further with machining characteristics, such as tool wear rate (TWR), material removal rate (MRR), deep grooves machining, and nozzle nomenclature.