Recent Advances in the Machining of Titanium Alloys using Minimum Quantity Lubrication (MQL) Based Techniques

Titanium alloys are generally known as difficult-to-machine materials because of their low machinability ratings. Their usage is favored for demanding sectors because of their high strength to weight ratio, high corrosion resistance and ability to operate at elevated temperatures. Machining of titanium alloys results in higher environmental burden, because they require high energy and generous amount of cutting fluids during machining. It is a well-known fact that most of the cutting fluids are toxic and non-biodegradable in nature and their disposal is costly. Therefore, researchers in metal cutting are keen to explore the potential of minimum quantity lubrication (MQL) and minimum quantity cooling lubrication (MQCL) based cooling techniques as an alternate to conventional flood cooling. When MQL and MQCL techniques are used by employing biodegradable vegetable based oils then there is an encouraging potential of replacing the non-biodegradable cutting fluids. This study documents the recent experimental and numerical advances achieved in the MQL and MQCL assisted techniques for machining titanium alloys. The study also highlights the current challenges in this area and recommends future work to address these challenges.