A Review paper on Sustainable machining with Minimum Quantity Lubrication (MQL)

Abstract

In the highly competitive global manufacturing sector, the implementation of cost-effective and environmentally responsible machining strategies has become essential to achieve high surface integrity, dimensional accuracy, and process efficiency. Conventional metal cutting operations extensively rely on cutting fluids for thermal regulation, lubrication at the tool-chip interface, and effective chip evacuation, thereby improving tool life and machining stability. However, the ongoing reliance on mineral oil-based cutting fluids has become a major concern because of their poor biodegradability, non-renewable nature, complicated disposal processes, and possible risks to workers’ health. In response, minimum quantity lubrication (MQL) has gained attention as a sustainable machining approach, significantly lowering cutting fluid usage while still providing satisfactory tribological and heat-control performance. This paper provides an extensive review of recent advancements in MQL-assisted machining across a wide variety of materials, including ferrous and non-ferrous alloys, superalloys, and composite materials. Furthermore, the environmental implications of MQL adoption are critically examined within the framework of sustainable manufacturing, with emphasis on reducing ecological impact, improving operator safety, and supporting compliance with stringent environmental regulations.