Application of cutting fluids in machining of titanium alloys-a review

Titanium alloys are widely used in aerospace, biomedical, and other engineering areas due to their superior properties. However, machining of titanium alloys has always been a challenge due to the high temperatures and tool wear rates. Dry machining has a limited range of permissible cutting conditions and is hence not suitable for industrial production. As a solution, flood cooling using cutting fluids is conventionally used to reduce the cutting temperatures. However, it is often discouraged in light of the associated environmental and health hazards. In order to achieve sustainable machining, different strategies for applying the cutting fluids are developed. Some of the prominent methods include minimum quantity lubrication (MQL), minimum quantity cooled lubrication (MQCL), and cryogenic cooling. This paper provides a comprehensive review of the available recent literature on such studies. Each of these techniques and results obtained in the studies has been discussed with emphasis on the advantages and limitations of each method. Major conclusions drawn are that coated carbides are better and machinability is greatly affected by the microstructure of the material. MQL certainly improved compared to other methods while cryogenic or super cooled cutting fluid application (MQCL) has been found to be better for specific situations. Use of nanofluids for titanium is not very popular among the researchers.